JP7211378B2 - Wavelength conversion substrate, display, and method for manufacturing wavelength conversion substrate - Google Patents

Description

The present invention relates to a wavelength conversion substrate, a display, and a method of manufacturing a wavelength conversion substrate.

In recent years, with the development of information terminal devices such as smartphones and tablets, and the high definition of flat panel displays such as televisions, the demand for higher performance of displays is increasing. Among them, wavelength-converting OLED displays and LED displays are attracting attention as high-performance displays. These displays use active matrix-driven OLEDs and LEDs as light sources, and display in full color by changing at least part of the light with a wavelength conversion material, and are excellent in contrast and color reproducibility.

As a method of using an OLED as a light source, a method of using an OLED that emits blue light is known (Patent Document 1). In this case, the blue sub-pixel transmits and scatters the light from the OLED without wavelength conversion, and the green and red sub-pixels change the blue light from the OLED to green and red by the wavelength conversion material, respectively.

As a method of using an LED as a light source, in addition to a method of using a blue-emitting LED similar to an OLED and using a wavelength-converting material to partially change the color of the light to red or green, an ultraviolet-emitting LED is used and a wavelength-converting material is used. A method of changing colors to blue, green, and red is known (Patent Document 2).

These wavelength-converted displays require a patterned arrangement of wavelength-converting materials with sizes corresponding to the sub-pixels of the OLED or LED light sources. A photolithography method and an inkjet method (Patent Document 3) are known as methods of patterning a wavelength conversion material.

Special Table No. 2006-501617 Special table 2016-523450 WO2018/123103

However, in the photolithography method, the wavelength conversion material is applied to the entire surface, and after a predetermined position is exposed to light, most of the material is removed by development, so the loss of the wavelength conversion material is large. It was a necessary and complicated task. In addition, the inkjet method is excellent in material efficiency because the wavelength conversion layer can be formed only at the desired position. There was a problem that the particle components such as the wavelength conversion material settled in the ink, and the ink jet nozzle was easily clogged.

On the other hand, a nozzle coating method is known as a paste coating method. FIG. 12 shows a schematic diagram showing a wavelength conversion paste coating method by a nozzle coating method. The nozzle coating method has a space (manifold) for storing the paste 5 inside the coating head 4, and controls the pressure through the pressure pipe 6 connected to the space while moving relative to the substrate 3. In this application method, the paste 5 is applied by discharging the paste 5 from the discharge port 7 by introducing compressed air. In the nozzle coating method, since the viscosity of the paste can be higher than that in the ink jet method, nozzle clogging due to sedimentation of the particle component can be suppressed by designing the paste to have a high viscosity.

However, in the nozzle coating method, the paste is applied while continuously ejecting it, so the paste is applied in stripes, and the wavelength conversion paste containing the wavelength conversion material is more expensive than the inkjet method, which can apply a predetermined amount only to the desired position. There was a problem that the usage amount of In addition, if the shape of the barrier ribs suitable for the nozzle coating method is a linear shape with a uniform opening width in the direction parallel to the stripes, light leakage to adjacent sub-pixels in the direction parallel to the stripes occurs remarkably. I had a problem. Also, in the case of the lattice shape, if the width of the partition wall in the direction perpendicular to the stripe (hereinafter referred to as the horizontal partition wall) is narrow, the light to the sub-pixels adjacent in the direction parallel to the stripe is emitted similarly to the stripe shape. Leakage occurs, and when the partition wall is thick, there is a problem that the paste rides on the partition wall. In any of the above, when the partition wall width in the direction parallel to the stripes is narrow, there is a problem that the light leaks to the sub-pixels of the openings adjacent in the direction perpendicular to the stripes, resulting in color mixture.

As a special partition shape, although not suitable for a wavelength conversion display, a lattice-shaped partition having a flow path in a direction orthogonal to the stripes (Japanese Patent Application Laid-Open No. 2009-86155) has been proposed. In this shape, there is a problem that light is more likely to leak in the direction parallel to the stripes after passing through the channel portion, compared to a normal lattice shape.

Accordingly, it is an object of the present invention to provide a wavelength conversion substrate that can easily form a wavelength conversion layer, reduce the amount of wavelength conversion material used, and suppress light diffusion to adjacent sub-pixels.

In order to solve the above problems, the wavelength conversion substrate of the present invention has the following configuration. i.e.
A wavelength conversion substrate having a wavelength conversion layer in openings of a substrate and a substrate with partitions having partitions, wherein the openings partitioned by the partitions are stripe-shaped, and the aperture ratio of the openings is 60% or less. , the opening has a structure in which a portion with a large opening width and a portion with a small opening width are repeated in a direction parallel to the stripe, and the maximum value W _max and the minimum value W _min of the opening width in the repeating unit of the repeating structure is a wavelength conversion substrate that satisfies the following relational expression (1).

_Wmax / _Wmin ≧2 (1)
The display of the present invention has the following configuration. i.e.
A display having the wavelength conversion substrate and an OLED or LED as a light source.

A method for manufacturing a wavelength conversion substrate according to the present invention has the following configuration. i.e.
A method for manufacturing a wavelength conversion substrate having a wavelength conversion layer in an opening of a substrate and a substrate with partitions, wherein the openings partitioned by the partitions have a stripe shape and an aperture ratio of the openings is 60% or less. and the opening has a structure in which a portion with a large opening width and a portion with a small opening width are repeated in a direction parallel to the stripe, and the maximum value W _max and the minimum value W of the opening width in the repeating unit of the repeating structure. A method for manufacturing a wavelength conversion substrate, comprising a step of applying a wavelength conversion paste to the opening of the wavelength conversion substrate with a nozzle so that _min satisfies the following relational expression.

_Wmax / _Wmin ≧2 (1)
In the wavelength conversion substrate of the present invention, it is preferable that at least one or more of the openings in the repeating unit satisfy the following relational expression, where W is the width of the opening at any one location.

_Wmax >W> _Wmin (2)
Further, in the wavelength conversion substrate of the present invention, in the opening, any two openings between the location where the opening width is the maximum value W _max and the location where the opening width is the minimum value W _min Regarding the width of the opening, it is preferable that the following relational expression is satisfied at all points, where W _a is the width of the opening on the side closer to W _max and W _b is the width on the side closer to W _min .

W _max >W _a >W _b >W _min (3)

The wavelength conversion substrate of the present invention can easily form a wavelength conversion layer, can reduce the amount of wavelength conversion material used, and can suppress light diffusion to adjacent sub-pixels.

1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. FIG. 4 is a top view showing one mode of a substrate with partitions; 1 is a top view showing one mode of a substrate with partitions of the present invention. FIG. FIG. 4 is a top view showing one mode of a substrate with partitions; It is a top view which shows one aspect|mode of the conventional board|substrate with a partition. It is a top view which shows one aspect|mode of the conventional board|substrate with a partition. It is a schematic diagram showing a paste coating method by a nozzle coating method. FIG. 4 is a top view showing one mode of a wavelength conversion substrate having a wavelength conversion layer in an opening of a substrate with partitions having a substrate and partitions. FIG. 14 is a cross-sectional view of the wavelength conversion substrate taken along the line AA' shown in FIG. 13;

A wavelength conversion substrate of the present invention has a wavelength conversion layer in an opening of a substrate with partitions having a substrate and partitions.

In the present invention, the substrate functions as a support for the substrate with partition walls. Examples of substrates include glass plates, resin plates, and resin films. Non-alkali glass is preferable as the material of the glass plate. Polyester, (meth)acrylic polymer, transparent polyimide, polyethersulfone and the like are preferable as materials for the resin plate and the resin film. The thickness of the glass plate and the resin plate is preferably 1 mm or less, more preferably 0.8 mm or less. The thickness of the resin film is preferably 100 μm or less.

In the present invention, the substrate with partition walls has partition walls on the substrate. In addition, in the present invention, on the side of the substrate having the partition wall, a portion defined by the partition wall and not formed with the partition wall is referred to as an opening.

In the present invention, the openings defined by the partition walls have a stripe shape. The stripe shape refers to a shape in which approximately linear openings are repeated in a direction parallel to the linear direction. Since the openings are stripe-shaped, the wavelength conversion layer can be easily formed by a nozzle coating method. The substantially linear shape is not limited to a completely linear shape, and may meander or deviate in a direction orthogonal to the linear direction within a range that does not intersect the center lines of adjacent openings. Further, the substantially straight openings may be continuous openings or discontinuous openings having horizontal partition walls.

In the present invention, the aperture ratio of the opening is 60% or less. If the opening ratio of the openings exceeds 60%, the usage amount of the wavelength conversion material cannot be reduced. Moreover, the barrier ribs are not formed to have a large width, and the transmission and diffusion of light to adjacent sub-pixels in the direction parallel to the stripes and in the direction orthogonal to the stripes cannot be suppressed. The aperture ratio is more preferably 50% or less, more preferably 40% or less.

In the present invention, the width of the opening in the direction perpendicular to the stripe is called the width of the opening. In the present invention, the opening has a structure in which portions with a large opening width and portions with a small opening width are repeated in a direction parallel to the stripes. The number of repetitions is preferably equal to or greater than the number of display pixels in the direction parallel to the stripes.

In the present invention, the maximum value W _max and the minimum value W _min of the opening width within one repeating unit of the repeating structure satisfy the following relational expression.

_Wmax / _Wmin ≧2 (1)
If the above relational expression (1) is not satisfied, light leakage to sub-pixels adjacent in the direction parallel to the stripe cannot be suppressed. In addition, in the present invention, a location where a horizontal partition exists in the opening and the opening is discontinuous is regarded as not having an opening, and such a location is not set to W _min =0.

Furthermore, with respect to the openings in the repeating unit, it is preferable that at least one opening satisfies the following relational expression (2), where W is the width of the opening at one arbitrary location.

_Wmax >W> _Wmin (2)
By satisfying the above relational expression (2), it is possible to suppress the rapid width change of the opening. Film thickness unevenness due to defects is less likely to occur. Examples of partition wall shapes that satisfy the above relational expression (2) include the partition wall shapes shown in FIGS. For example, in FIG. ₂ , when W2 is replaced by W, the above relational expression (2) is satisfied. For any two opening widths in the range between the point where the opening width is the maximum value W _max and the point where the opening width is the minimum value W _min , the opening width on the side closer to W _max is W _a , When the side close to W _min is set to W _b , it is more preferable to satisfy the following relational expression (3) at all points because it is more difficult to cause film thickness unevenness.

W _max >W _a >W _b >W _min (3)
Examples of partition wall shapes that satisfy the above relational expression (3) include, for example, the partition wall shapes shown in FIGS. For example, in _FIG . ₃ , of _two arbitrary points in the tapered portion between W2 and W3, the width of the partition wall opening near W2 is W _{a ,} and the width of the partition wall opening near W3 is W a . W _b satisfies the above relational expression (3).

The partition in the present invention preferably has a pattern corresponding to sub-pixels in pixels of the display. The number of pixels of the display is, for example, 2,000 vertically and 4,000 horizontally. The number of pixels affects the resolution (fineness) of the displayed image. Therefore, it is necessary to form the number of pixels according to the required image resolution and the screen size of the display, and it is preferable to determine the pattern formation dimensions of the barrier ribs accordingly.

The partition walls preferably have a function of preventing transmission and scattering of light from a certain sub-pixel to adjacent sub-pixels.

In the present invention, the openings may be continuous in the direction parallel to the stripes or discontinuous with horizontal partitions. When the barrier ribs have a function of preventing transmission and scattering of light, the horizontal barrier ribs may suppress scattering of light in a direction parallel to the stripes. However, if the width of the horizontal barrier ribs is large, part of the wavelength conversion layer formed by the nozzle coating method may also exist on the horizontal barrier ribs. It is preferable that the ratio of the length in the direction parallel to the stripe of the opening (hereinafter referred to as the opening length fraction) is 80% or more. More preferably, it is 90% or more.

FIG. 13 shows a top view of one mode of the wavelength conversion substrate of the present invention. Further, FIG. 14 shows a cross-sectional view along AA' as an example of a cross-sectional view of the wavelength conversion substrate of FIG. 13 in a direction orthogonal to the stripe direction. It has a patterned partition 1 on a substrate 3 and has a wavelength conversion layer 8 in the opening sectioned by the partition.

The barrier ribs preferably have a reflectance of 20 to 90% per 10 μm thickness at a wavelength of 550 nm. By setting the reflectance to 20% or more, the luminance of the display can be improved by utilizing the reflection on the side surfaces of the partition walls. On the other hand, the reflectance is preferably 90% or less from the viewpoint of improving the partition pattern formation accuracy. Here, the thickness of the partition refers to the length of the partition in the vertical direction (height direction) with respect to the substrate. In the case of the substrate with partition walls shown in FIG. Note that the horizontal length of the partition with respect to the substrate is the width of the partition. In the case of the substrate with partition walls shown in FIG. 13, the width of the partition walls 1 is represented by L. In FIG. 1, the direction parallel to the stripes is indicated by an upward arrow (also in FIGS. 2 to 11 and 13).

The thickness of the barrier ribs is preferably larger than the thickness of the cured wavelength conversion paste when the cells of the substrate with barrier ribs contain the cured wavelength conversion paste. Specifically, the thickness of the partition wall 1 is preferably 0.5 μm or more, more preferably 5 μm or more. On the other hand, the thickness of the partition is preferably 100 μm or less, more preferably 70 μm or less, and even more preferably 50 μm or less, from the viewpoint of extracting light emitted from the bottom of the layer containing the color-converting luminescent material more efficiently. In addition, the width of the partition walls should be sufficient to improve brightness by utilizing light reflection on the side surfaces of the partition walls and to suppress color mixture of emitted light from adjacent cured products of the wavelength conversion paste due to light leakage. Specifically, the width of the partition wall is preferably 5 μm or more, more preferably 10 μm or more.

In the present invention, it is preferable that between adjacent stripes, locations having an opening width of _Wmax are arranged in a zigzag pattern. In such a configuration, since the partition wall width in the direction perpendicular to the stripes is increased, it is possible to effectively suppress color mixture.

In the present invention, the wavelength conversion layer contains a wavelength conversion material. In the present invention, the wavelength conversion material refers to a material having wavelength conversion properties that absorbs electromagnetic waves and emits electromagnetic waves having a wavelength different from the wavelength of the absorbed electromagnetic waves. A wavelength conversion paste having a wavelength conversion material is patterned and applied to prepare a wavelength conversion substrate, and a full color display can be obtained by combining it with an OLED light source or an LED light source.

Inorganic phosphors and/or organic phosphors are preferably used as the wavelength conversion material. For example, in the case of a display in which an OLED that emits blue light and a wavelength conversion substrate are combined, a red phosphor that emits red fluorescence when excited by blue excitation light is used in a region corresponding to a red sub-pixel. It is preferable to use it as a wavelength conversion material, and it is preferable to use a green phosphor that emits green fluorescence when excited by blue excitation light as a wavelength conversion material in the region corresponding to the green subpixel. Preferably, no wavelength conversion material is used in the region corresponding to . Similarly, the wavelength conversion substrate of the present invention can also be used for a display that uses blue LEDs or ultraviolet light emitting LEDs corresponding to each sub-pixel as a backlight. Light emission of each sub-pixel can be turned ON/OFF by active matrix driving of OLEDs and LEDs.

Inorganic phosphors emit light in colors such as green and red. Examples of inorganic phosphors include those that are excited by excitation light with a wavelength of 400 to 500 nm and have a peak emission spectrum in the region of 500 to 700 nm, inorganic semiconductor fine particles called quantum dots, and the like. Examples of the shape of the former inorganic phosphor include a spherical shape and a columnar shape. Examples of such inorganic phosphors include YAG-based phosphors, TAG-based phosphors, sialon-based phosphors, Mn ⁴⁺ -activated fluoride complex phosphors, and the like. You may use 2 or more types of these.

Among these, quantum dots are preferred. Quantum dots have sharp peaks in emission spectra compared to other phosphors, and thus can improve the color reproducibility of displays.

Quantum dot materials include, for example, II-IV group, III-V group, IV-VI group, and IV group semiconductors. Examples of these inorganic semiconductors include Si, Ge, Sn, Se, Te, B, C (including diamond), P, BN, BP, BAs, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, ZnO, ZnS, ZnSe, ZnTe, CdS, CdSe, CdSeZn, CdTe, HgS, HgSe, HgTe, BeS, BeSe, BeTe, MgS, MgSe, GeS, GeSe, GeTe, SnS, _SnSe , _SnTe , PbO, PbS, PbSe, PbTe, CuF, CuCl, CuBr, CuI, _Si3N4 , _{Ge3N4 , Al2O3} and the like. You may use 2 or more types of these.

Quantum dots may contain p-type dopants or n-type dopants. Quantum dots may also have a core-shell structure. In the core-shell structure, any appropriate functional layer (single layer or multiple layers) may be formed around the shell depending on the purpose, and the shell surface may be surface-treated and/or chemically modified. .

Examples of the shape of the quantum dots include spherical, columnar, scaly, plate-like, and irregular shapes. The average particle size of quantum dots can be selected according to the desired emission wavelength, and is preferably 1 to 30 nm. If the average particle size of the quantum dots is 1 to 10 nm, the peaks in the emission spectrum can be made sharper in each of blue, green and red. For example, when the average particle size of the quantum dots is about 2 nm, they emit blue light, when they are about 3 nm, they emit green light, and when they are about 6 nm, they emit red light. The average particle size of the quantum dots is preferably 2 nm or more, and preferably 8 nm or less. The average particle size of quantum dots can be measured by a dynamic light scattering method. A dynamic light scattering photometer DLS-8000 (manufactured by Otsuka Electronics Co., Ltd.) can be used as an apparatus for measuring the average particle size.

Examples of the organic phosphor include, for example, a pyrromethene derivative having a basic skeleton represented by the following structural formula (A) as a phosphor that emits red fluorescence when excited by blue excitation light; Examples of fluorescent substances that emit fluorescence include pyrromethene derivatives having a basic skeleton represented by the following structural formula (B). Other examples include perylene-based derivatives, porphyrin-based derivatives, oxazine-based derivatives, and pyrazine-based derivatives that emit red or green fluorescence depending on the selection of substituents. You may contain 2 or more types of these. Among these, pyrromethene derivatives are preferred because of their high quantum yield. A pyrromethene derivative can be obtained, for example, by the method described in JP-A-2011-241160.

Since the organic phosphor is soluble in a solvent, it is possible to easily form a layer containing the wavelength conversion material with a desired thickness.

The wavelength conversion layer of the present invention may contain light scattering particles. By containing the light-scattering particles, blue light and ultraviolet light are scattered in the wavelength conversion layer, thereby lengthening the optical path length and improving the light conversion efficiency of the wavelength conversion material.

The light-scattering particles are preferably barium sulfate, aluminum oxide, zirconium oxide, zinc oxide, or titanium oxide. You may contain 2 or more types of these.

The refractive index of the light scattering particles at a wavelength of 587.5 nm is preferably 1.60 to 2.70. By setting the refractive index of the light-scattering particles to 1.60 or more, the scattering of blue light in the wavelength conversion layer by the light-scattering particles is improved, and the light conversion efficiency of the wavelength conversion material is likely to be improved. On the other hand, by setting the refractive index of the light-scattering particles to 2.70 or less, excessive scattering by the light-scattering particles is suppressed, and emitted light after wavelength conversion is easily extracted from the cell. When two or more kinds of light-scattering particles are contained, the refractive index of at least one kind is preferably within the above range.

From the viewpoint of further improving the light conversion efficiency, the content of the light scattering particles is preferably 1% by weight or more, more preferably 5% by weight or more, and even more preferably 10% by weight or more in the solid content. On the other hand, the content of the light-scattering particles is preferably 70% by weight or less, more preferably 60% by weight or less, and 50% by weight or less in the solid content from the viewpoint of suppressing a decrease in luminous efficiency due to concentration quenching of the wavelength conversion material. is more preferred. As used herein, the solid content means all of the components contained in the wavelength conversion paste, excluding volatile components such as solvents. The amount of solid content can be obtained by heating the wavelength conversion paste at 150° C. for 1 hour to evaporate volatile components and weighing the residue.

In the present invention, the wavelength conversion layer is preferably formed by curing a wavelength conversion paste. The wavelength conversion paste is a paste material containing a wavelength conversion material, and can be easily applied to the substrate with partition walls by a nozzle coating method by appropriately designing the composition. The method of curing the wavelength conversion paste is not particularly limited, but a method of curing a wavelength conversion paste containing a polymerizable compound with heat or light, or a method of curing a wavelength conversion paste containing a solvent by volatilizing the solvent by heating. etc.

In the present invention, the wavelength conversion paste may contain a monomer as a polymerizable compound. A monomer in the present invention refers to a compound that is polymerized by active species generated by reaction of a polymerization initiator, which will be described later.

A monomer in the present invention is preferably a compound having an ethylenically unsaturated double bond in the molecule. Preferably, the monomer has two or more ethylenically unsaturated double bonds in the molecule. Considering the easiness of radical polymerizability, the monomer preferably has a (meth)acrylic group. Moreover, the double bond equivalent of the monomer is preferably 400 g/mol or less from the viewpoint of further improving sensitivity in patterning.

Examples of monomers include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, diethylene glycol dimethacrylate, and triethylene. glycol dimethacrylate, tetraethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, 1,3-butanediol diacrylate, 1, 3-butanediol dimethacrylate, neopentyl glycol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol dimethacrylate, 1 , 10-decanediol dimethacrylate, dimethylol-tricyclodecane diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripenta Erythritol heptaacrylate, tripentaerythritol octaacrylate, tetrapentaerythritol nonaacrylate, tetrapentaerythritol decaacrylate, pentapentaerythritol undecaacrylate, pentapentaerythritol dodecaacrylate, tripentaerythritol heptamethacrylate, tripentaerythritol octamethacrylate, tetrapentaerythritol nonamethacrylate, tetrapentaerythritol decamethacrylate, pentapentaerythritol undecamethacrylate, pentapentaerythritol dodecamethacrylate, dimethylol-tricyclodecane diacrylate and the like. You may contain 2 or more types of these.

In the present invention, the content of the monomer in the wavelength conversion paste is preferably 1% by weight or more, more preferably 10% by weight or more, and 30% by weight or more of the solid content, from the viewpoint of increasing the solid content of the wavelength conversion paste. is more preferred. On the other hand, from the viewpoint of stabilizing ejection from the nozzle, the monomer content is preferably 80% by weight or less, more preferably 70% by weight or less, in the solid content.

In the present invention, the wavelength conversion paste may contain a polymerization initiator. By containing a polymerization initiator and a monomer, by reacting the polymerization initiator with light irradiation or heating, polymerization of the monomer proceeds due to active species generated from the polymerization initiator, and the exposed portion of the wavelength conversion paste is removed. Can be cured.

The polymerization initiator is a radical initiator or a cationic initiator, that is, any one that reacts with light (including ultraviolet rays and electron beams) or heat to generate active species such as radicals and cations. good. Among these, radical initiators are preferred. Examples of polymerization initiators include 2-methyl-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4- α-Aminoalkylphenone compounds such as morpholin-4-yl-phenyl)-butan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1;2,4 ,6-trimethylbenzoylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethylpentyl)-phosphine oxide, etc. Acylphosphine oxide compounds; 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, 1-[4-(phenylthio)phenyl]octane-1,2-dione=2-(O-benzoyl oxime)], 1-phenyl-1,2-butadione-2-(O-methoxycarbonyl)oxime, 1,3-diphenylpropanetrione-2-(O-ethoxycarbonyl)oxime, ethanone, 1-[9-ethyl -6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime) and other oxime ester compounds; benzyl ketal compounds such as benzyl dimethyl ketal; 2-hydroxy-2-methyl -1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl ) ketones, α-hydroxyketone compounds such as 1-hydroxycyclohexyl-phenylketone; benzophenone, 4,4-bis(dimethylamino)benzophenone, 4,4-bis(diethylamino)benzophenone, methyl O-benzoylbenzoate, 4- phenylbenzophenone, 4,4-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenylsulfide, alkylated benzophenone, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, etc. benzophenone compounds; 2,2-diethoxyacetophenone, 2,3-diethoxyacetophenone, 4-t-butyldichloroacetophenone, benzalacetophenone, 4-azidobenzalacetophenone acetophenone compounds such as amine; aromatic ketoester compounds such as methyl 2-phenyl-2-oxyacetate; ethyl 4-dimethylaminobenzoate, (2-ethyl)hexyl 4-dimethylaminobenzoate, ethyl 4-diethylaminobenzoate, Examples include benzoic acid ester compounds such as methyl 2-benzoylbenzoate. You may contain 2 or more types of these.

In the present invention, since the wavelength conversion paste suppresses coloring due to the polymerization initiator, 2,4,6-trimethylbenzoylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2 ,6-dimethoxybenzoyl)-(2,4,4-trimethylpentyl)-phosphine oxide or other acylphosphine oxide-based polymerization initiator is preferably contained.

In the present invention, the content of the polymerization initiator in the wavelength conversion paste is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, based on the solid content, from the viewpoint of efficiently advancing radical curing. On the other hand, the content of the polymerization initiator is preferably 20% by weight or less, more preferably 10% by weight or less, based on the solid content, from the viewpoint of suppressing elution of the remaining polymerization initiator and the like and further improving yellowing.

In the present invention, the wavelength conversion paste may appropriately contain a polymer, solvent, dispersant, and the like.

In the present invention, when the wavelength conversion paste contains a polymer, the polymer includes, for example, polyvinyl acetate, polyvinyl alcohol, ethyl cellulose, methyl cellulose, polyethylene, silicon resin such as polymethylsiloxane or polymethylphenylsiloxane, polystyrene, butadiene/styrene. Copolymers, polystyrene, polyvinylpyrrolidone, polyamides, high molecular weight polyethers, copolymers of ethylene oxide and propylene oxide, polyacrylamides or acrylic resins are preferred.

In the present invention, when the wavelength conversion paste contains a solvent, the solvent includes, for example, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, 4-methyl-2-pentanol, 3 - alcohols such as methyl-2-butanol, 3-methyl-3-methoxy-1-butanol, diacetone alcohol; glycols such as ethylene glycol and propylene glycol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol Ethers such as monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol mono-t-butyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethyl ether; methyl ethyl ketone , acetylacetone, methyl propyl ketone, methyl butyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, ketones such as 2-heptanone; dimethylformamide, amides such as dimethylacetamide; ethyl acetate, propyl acetate, butyl acetate, isobutyl Acetates such as acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl lactate, ethyl lactate, butyl lactate; toluene, xylene, hexane, Aromatic or aliphatic hydrocarbons such as cyclohexane; γ-butyrolactone, N-methyl-2-pyrrolidone, dimethylsulfoxide and the like are preferred.

In the present invention, the viscosity of the wavelength conversion paste is measured by mounting a plate P35 Ti L manufactured by the same company on a rheometer (HAAKE MARS; manufactured by Thermo Fisher Scientific Co., Ltd.) and setting the gap to 200 μm. , and a viscosity of 1,000 to 500,000 mPa·s at a shear rate of 1 sec ⁻¹ . When the viscosity is 1000 mPa·s or more, particle components such as light-scattering particles are less likely to settle even when the paste is stored for a long period of time after preparation. More preferably, the viscosity is 3,000 mPa·s or more, and even more preferably 5,000 mPa·s or more. Further, by setting the viscosity to 500,000 mPa·s or less, it becomes easier to stably discharge even when pressurized with low-pressure compressed air. More preferably, the viscosity is 400,000 mPa·s or less, and even more preferably 300,000 mPa·s or less.

In the present invention, when the wavelength conversion paste contains a dispersant, for example, "Disperbyk" (registered trademark) 106, 108, 110, 180, 190, 2001, 2155, 140, 145 (above, commercial products (manufactured by Bik-Chemie Co., Ltd.) and the like are preferred.

The wavelength conversion substrate of the present invention is preferably produced by applying a wavelength conversion paste to the substrate with barrier ribs of the present invention by a nozzle coating method and curing the paste.

Next, the display of the present invention will be explained. A display of the present invention has the wavelength conversion substrate and a light source. As the light source, a light source selected from blue OLEDs, blue LEDs, and ultraviolet light emitting LEDs capable of active matrix driving is preferable.

A method for manufacturing the display of the present invention will be described with an example of a display having the wavelength conversion substrate of the present invention and a blue OLED. A glass substrate having a TFT pattern capable of active matrix driving is coated with a photosensitive polyimide resin, and an insulating film is formed by photolithography. After sputtering aluminum as a back electrode layer, patterning is performed by a photolithography method to form a back electrode layer in the openings where there is no insulating film. Subsequently, tris(8-quinolinolato)aluminum (hereinafter abbreviated as Alq3) was deposited as an electron-transporting layer by a vacuum vapor deposition method, and then Alq3 as a light-emitting layer. ,2-diphenylvinyl)biphenyl to form a white light-emitting layer. Next, N,N'-diphenyl-N,N'-bis(α-naphthyl)-1,1'-biphenyl-4,4'-diamine is deposited as a hole transport layer by vacuum deposition. Finally, ITO is deposited as a transparent electrode by sputtering to fabricate an OLED having a blue light-emitting layer. A display can be produced by making the OLED obtained in this manner face the wavelength conversion substrate and bonding them with a sealant.

Note that the wavelength conversion substrate itself of the present invention may have an OLED or an LED. In this case, a display can be produced by sequentially forming a partition wall and a wavelength conversion layer on a substrate having an OLED or an LED.

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited to these scopes.

(Method for measuring average particle size of light-scattering particles)
Light-scattering particles are put into a water-filled sample chamber of a particle size distribution analyzer (MT3300; manufactured by Nikkiso Co., Ltd.), subjected to ultrasonic treatment for 300 seconds, and then the particle size distribution is measured. % was taken as the average particle size.

(Raw material for wavelength conversion paste)
The raw materials used for preparing the wavelength conversion paste are as follows.
Light-scattering particles: AA-1.5 (alumina, average particle size 1.6 μm, alumina, manufactured by Sumitomo Chemical Co., Ltd.)
Wavelength conversion material 1: Lumidot 640 CdSe (red quantum dot material, manufactured by Sigma-Aldrich)
Wavelength conversion material 2: Lumidot 530 CdSe (green quantum dot material, manufactured by Sigma-Aldrich)
Photopolymerization initiator: "Irgacure" (registered trademark) OXE01 (manufactured by BASF Japan Ltd.)
Monomer: NK-9PG (polypropylene glycol #400 dimethacrylate which is a bifunctional methacrylate) (manufactured by Shin-Nakamura Chemical Co., Ltd.)
Polymer: "Ethocel" (registered trademark) STD7 (I) (cellulose ethyl ether) (manufactured by DDP Specialty Products Japan Co., Ltd.)
Solvent: Propylene glycol monomethyl ether acetate (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
(Preparation of wavelength conversion paste)
25 parts by weight of light scattering particles, 5 parts by weight of wavelength conversion material 1, 0.1 parts by weight of photopolymerization initiator, 34.9 parts by weight of monomer, 15 parts by weight of polymer, and 20 parts by weight of solvent were weighed. Then, after kneading with a three-roller kneader, the mixture was filtered through an SHP-400 filter (manufactured by Roki Techno Co., Ltd.) while applying a pressure of 100 to 400 kPa with air to obtain a wavelength conversion paste for red subpixels. Also, a wavelength conversion paste for green subpixels was obtained in the same manner except that the wavelength conversion material 1 was replaced with the wavelength conversion material 2. A light scattering paste for blue subpixels was obtained in the same manner, except that wavelength conversion material 1 was not added.

(Analysis method of polysiloxane solution)
The solid content concentration of the polysiloxane solution was obtained by the following method. 1.5 g of the polysiloxane solution was put into an aluminum cup and heated at 250° C. for 30 minutes using a hot plate to evaporate the liquid. The weight of the solid content remaining in the aluminum cup after heating was weighed, and the solid content concentration of the polysiloxane solution was obtained from the ratio to the weight before heating.

The weight average molecular weight of polysiloxane was obtained by the following method. Using a GPC analyzer (HLC-8220; manufactured by Tosoh Corporation) and using tetrahydrofuran as a fluidized bed, GPC analysis was performed based on "JIS K 7252-3 (enacted date = 2008/03/20)". , the polystyrene-equivalent weight-average molecular weight was measured.

The content ratio of each repeating unit in polysiloxane was obtained by the following method. A polysiloxane solution is injected into a “Teflon” (registered trademark) NMR sample tube with a diameter of 10 mm and ²⁹ Si-NMR measurement is performed, and the Si derived from a specific organosilane is compared with the integrated value of the entire Si derived from the organosilane. The content ratio of each repeating unit was calculated from the ratio of the integrated value of. ²⁹ Si-NMR measurement conditions are shown below.
Apparatus: Nuclear magnetic resonance apparatus (JNM-GX270, manufactured by JEOL Ltd.)
Measurement method: Gated decoupling method Measurement nucleus frequency: 53.6693 MHz (29Si nucleus)
Spectrum width: 20,000Hz
Pulse width: 12 μs (45° pulse)
Pulse repetition time: 30.0 seconds Solvent: Acetone-d6
Reference substance: Tetramethylsilane Measurement temperature: 23°C
Sample rotation speed: 0.0 Hz.

(Synthesis of polysiloxane solution)
147.32 g (0.675 mol) of trifluoropropyltrimethoxysilane, 40.66 g (0.175 mol) of 3-methacryloxypropylmethyldimethoxysilane, and 3-trimethoxysilylpropylsuccinic acid were placed in a 1,000 mL three-necked flask. 26.23 g (0.10 mol) of anhydride, 12.32 g (0.05 mol) of 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane, 0.808 g of dibutylhydroxytoluene, propylene glycol monomethyl ether acetate ( 171.62 g of PGMEA) was charged, and an aqueous phosphoric acid solution prepared by dissolving 2.265 g of phosphoric acid (1.0% by weight relative to the charged monomers) in 52.65 g of water was added with stirring at room temperature over 30 minutes. . After that, the flask was immersed in an oil bath at 70° C. and stirred for 90 minutes, and then the oil bath was heated to 115° C. over 30 minutes. After 1 hour from the start of heating, the temperature of the solution (internal temperature) reached 100° C., and the solution was heated and stirred for 2 hours (internal temperature: 100 to 110° C.) to obtain a polysiloxane solution. A mixed gas of 95% by volume of nitrogen and 5% by volume of oxygen was flowed at 0.05 L/min during the temperature rise and heating and stirring. A total of 131.35 g of methanol and water, which are by-products, were distilled during the reaction. PGMEA was added to the obtained polysiloxane solution so that the solid content concentration was 40% by weight to obtain a polysiloxane solution. The weight average molecular weight of the obtained polysiloxane was 4,000. It is also derived from trifluoropropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride, and 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane in polysiloxane. The molar ratios of repeating units were 67.5 mol %, 17.5 mol %, 10 mol % and 5 mol %, respectively.

(Adjustment of partition wall resin composition)
As white pigment, titanium dioxide pigment (R-960, manufactured by BASF Japan Co., Ltd.) 5.00 g, and as black pigment, titanium nitride pigment (Nisshin Engineering Co., Ltd.) 0.02 g, polysiloxane solution as resin 5.00 g was mixed and dispersed using a mill-type dispersing machine filled with zirconia beads to obtain a pigment dispersion. Next, 9.98 g of pigment dispersion, 0.71 g of DAA, 1.57 g of polysiloxane solution, and as a photopolymerization initiator, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3 -yl]-, 1-(O-acetyloxime) (manufactured by BASF Japan Ltd.) 0.050 g, bis (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by BASF Japan Ltd.) 0 0.100 g of 1,2-diisopropyl-3-[bis(dimethylamino)methylene]guanidinium 2-(3-benzoylphenyl)propionate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a photobase generator , as a photopolymerizable compound, dipentaerythritol hexaacrylate (manufactured by Shinnippon Pharmaceutical Co., Ltd.) 1.20 g, as a liquid-repellent compound, a photopolymerizable fluorine-containing compound (“Megafac” (registered trademark) RS-76- E, manufactured by DIC Corporation) 1.00 g of 40% by weight PGMEA diluted solution, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate (manufactured by Daicel Corporation) 0.100 g, ethylenebis (Oxyethylene) bis [3-(5-tert-butyl-4-hydroxy-m-tolyl) propionate] (manufactured by BASF Japan Ltd.) 0.030 g, acrylic surfactant (“BYK” (registered trademark) 352, manufactured by BYK-Chemie Japan Co., Ltd.) was dissolved in 4.76 g of solvent PGMEA and stirred. Then, filtration was performed with a 5.0 μm filter to obtain a resin composition for partition walls.

(Preparation of substrate with partition walls)
A partition wall resin composition was spin-coated on a 10 cm square non-alkali glass substrate (manufactured by AGC Techno Glass Co., Ltd., thickness 0.7 mm), and a hot plate (SCW-636, manufactured by SCREEN Semiconductor Solutions Co., Ltd.) was applied. ) at a temperature of 90° C. for 2 minutes to prepare a dry film. The prepared dried film was formed into the partition shape of Examples 1 to 18 and Comparative Examples 1 to 5 described later using a parallel light mask aligner (PLA-501F, manufactured by Canon Inc.) and an ultrahigh pressure mercury lamp as a light source. It was exposed through a corresponding photomask with an exposure amount of 200 mJ/cm ² (i-line). Then, using an automatic developing device (AD-2000, manufactured by Takizawa Sangyo Co., Ltd.), shower development was performed using a 0.045% by weight potassium hydroxide aqueous solution for 100 seconds, and then rinsed with water for 30 seconds. Furthermore, using an oven (IHPS-222, manufactured by Espec Co., Ltd.), it is heated in the air at a temperature of 230 ° C. for 30 minutes, and is repeatedly placed on a glass substrate with a height of 22 μm and the shape of FIGS. A partition wall having a length L _unit of 300 μm in the direction parallel to the stripes of the structural unit cell (indicated by a square dotted line in the figure) and a length W _unit of 100 μm in the direction perpendicular to the stripes is formed in a 7 cm square range. A substrate with partition walls was produced.

(Evaluation method for partition wall shape and opening shape)
Optical microscopic images of the prepared partition substrate were taken in camera mode from above with a laser microscope (color 3D laser microscope VK-9710, manufactured by KEYENCE CORPORATION), and L ₁ to L ₅ and L _s in FIGS. , W ₁ to W ₅ , W _s were measured with the attached software. Further, W _max was the maximum value of W ₁ to W ₅ and W _min was the minimum value of W ₁ to W ₅ , and W _max /W _min was calculated. The aperture ratio was obtained by separating the partition wall portion and the opening portion by image processing of the microscope image, and calculating the area fraction of the opening portion in the unit lattice. Also, the opening length fraction was calculated by (L _unit -L _s )/L _unit ×100. If any one of W ₁ to W ₅ is W _max /4, the length fraction of the opening width of W _max /4 or less is (total length of L ₁ to L ₅ corresponding to that location)/L Calculated by _unit ×100.

(Evaluation method of wavelength conversion material usage rate)
A wavelength conversion paste was applied and cured on each substrate with partition walls of Examples 1 to 18 and Comparative Examples 1 to 5 by the following method, and the difference in weight of the substrate before and after was measured with a precision balance. Weight was calculated. The coating head used had 51 ejection openings with an ejection opening diameter of 50 μm and an ejection opening length of 130 μm arranged at a pitch of 300 μm in the longitudinal direction of the coating head. As a coating device, a multi-lab coater (manufactured by Toray Engineering Co., Ltd.) was used, and the position was aligned so that the ejection port at the left end of the nozzle came to the stripe portion 0.5 cm from the left end of the partition pattern. After aligning the direction parallel to the nozzle and the direction of travel of the nozzle, a pressure of 500 to 1,500 kPa is applied to the coating head by air, and the travel speed with respect to the substrate is changed within the range of 20 to 200 mm / s to form a green subpixel. While discharging the wavelength conversion paste for green sub-pixels, the wavelength conversion paste for green sub-pixels was applied to the substrate with the partition walls in a direction parallel to the long side direction of the partition walls. Next, the nozzle position was shifted by 100 μm in the direction perpendicular to the direction parallel to the stripes of the barrier ribs, and the coating was applied in the same manner. A green sub-pixel wavelength conversion paste was applied to the opening. Next, the position of the base is moved to the right by 1.5 cm in the direction perpendicular to the stripes of the barrier ribs, and the same operation is repeated three times. applied to the front opening. Then, it was dried on a hot plate at 100° C. for 10 minutes, and further cured by exposure with an ultra-high pressure mercury lamp at an exposure amount of 200 mJ/cm ² (i-line) in a nitrogen atmosphere to form a wavelength conversion layer. At this time, the coating pressure and advancing speed were adjusted so that the wavelength conversion layer had a thickness of 20 μm at the central portion of the unit lattice.

Separately, the green sub-pixel wavelength conversion paste was applied to a 10 cm square non-alkali glass substrate by spin coating, followed by drying and curing in the same manner to form a solid film of the wavelength conversion layer. At this time, the spin speed was adjusted so that the thickness of the wavelength conversion layer was 20 μm. After that, the substrate was cut into a size of 7 cm×6 cm and weighed, and the weight of the separately measured 7 cm×6 cm substrate was subtracted to calculate the weight of the solid film wavelength conversion layer.

From these measurement results, the usage rate of the wavelength conversion material was calculated by (weight of the wavelength conversion layer in the substrate with partition walls/weight of the solid film of the wavelength conversion layer)×100. If the usage rate of the wavelength conversion material exceeds 60%, the usage amount is too large and is not suitable. Also, the usage rate of the wavelength conversion material is preferably 50% or less, more preferably 40% or less.

(Evaluation method for riding on top of transverse bulkhead)
Among the wavelength conversion substrates produced by the above method, regarding the substrates of Examples 10 to 12 and Comparative Examples 1 and 2 having horizontal barrier ribs, whether or not the wavelength conversion layer exists on the horizontal barrier ribs, and if so, whether or not the wavelength conversion layer exists on the horizontal barrier ribs. The thickness was observed with a laser microscope. If the wavelength conversion layer is not seen on the horizontal barrier ribs, A is observed, but the wavelength conversion layer is found on the horizontal barrier ribs, but the thickness is less than 1 μm, B is 1 μm or more and less than 3 μm, C is the thickness. D indicates that the thickness is 3 μm or more and less than 10 μm, and E indicates that the thickness is 10 μm or more. The case of E is not suitable because a wide gap is formed when the wavelength conversion substrate and the OLED substrate or the LED substrate are bonded together.

(Evaluation method for overflow in lateral direction of opening)
The wavelength conversion substrate prepared by the above method is observed with a laser microscope, and whether or not the wavelength conversion layer exists outside the opening at the location where the opening width is W _min , and if it exists, its thickness is observed with a laser microscope. bottom. A is the case where no wavelength conversion layer exists outside the opening, B is the case where the wavelength conversion layer is visible on the partition but its thickness is less than 1 μm, and B is the case where the thickness of the wavelength conversion layer on the partition is 1 μm or more and less than 3 μm. was C.

(Evaluation method of wavelength conversion material film thickness unevenness)
The wavelength conversion substrate produced by the above method was observed with a laser microscope to evaluate thickness unevenness of the wavelength conversion layer in the unit lattice. Since unevenness is particularly likely to be seen near the partition wall where the width of the aperture changes, the thickness of the wavelength conversion layer at the center of the unit cell and the wavelength conversion of the aperture near the left partition where the aperture width starts to change from W _max The layer thickness was measured for each of nine unit cells and the average value was calculated. C is the case of If the thickness is non-uniform, the wavelength conversion efficiency may not be as designed, so the thickness difference is preferably as small as possible.

(Method for evaluating vertical light diffusion)
A wavelength conversion paste and a light scattering paste were applied and cured on the substrates with barrier ribs of Examples 1 to 18 and Comparative Examples 1 to 5 by the following method to prepare wavelength conversion substrates.

The coating head used had 51 ejection openings with an ejection opening diameter of 50 μm and an ejection opening length of 130 μm arranged at a pitch of 300 μm in the longitudinal direction of the coating head. As a coating device, a multi-lab coater (manufactured by Toray Engineering Co., Ltd.) was used, and the position was aligned so that the ejection port at the left end of the nozzle came to the stripe portion about 2.75 cm from the left end of the partition pattern. After aligning the direction parallel to the stripes and the traveling direction of the nozzle, a pressure of 500 to 1,500 kPa is applied to the coating head by air, and the advancing speed with respect to the substrate is changed within the range of 20 to 200 mm/s to obtain a blue sub. While discharging the light-scattering paste for pixels, the substrate with barrier ribs was filled with the light-scattering paste for blue sub-pixels by nozzle coating in a direction parallel to the long side direction of the barrier ribs. After that, it was dried on a hot plate at 100° C. for 10 minutes, and further cured by exposure with an ultra-high pressure mercury lamp at an exposure amount of 200 mJ/cm ² (i-line) in a nitrogen atmosphere. Next, the paste in the die is replaced with the green sub-pixel wavelength conversion paste, aligned with the barrier rib substrate in the same manner as described above, then the die position is shifted by 100 μm in the direction orthogonal to the stripes of the barrier rib, and the paste is applied in the same manner, dried, and dried. Cured by exposure. Further, the paste in the die was replaced with the wavelength conversion paste for red sub-pixel, and after alignment with the barrier rib substrate in the same manner as above, the die was applied in the same manner while shifting the position of the die by 200 μm in the direction perpendicular to the stripes of the barrier ribs, dried, and exposed. A wavelength-converting substrate was produced by curing the substrate with sub-pixels of three colors of blue, green, and red. At this time, the pressure and advancing speed during coating were adjusted so that the thickness of each wavelength conversion layer was 20 μm at the central portion of the unit lattice.

Blue light was irradiated to the center of one unit cell formed with the light scattering layer for blue subpixels of the wavelength conversion substrate manufactured by the above method, and light diffusion in the vertical direction, that is, in the direction parallel to the stripes was evaluated. bottom. As a blue light source, a blue backlight for LCD obtained by disassembling a commercially available liquid crystal monitor (SW2700PT, manufactured by BenQ) was used. In order to irradiate only the center of the unit cell, a photomask having one circular opening with a diameter of 30 μm was placed on the blue light source, and the center of the unit cell near the center of the partition substrate was placed thereon. However, the wavelength conversion substrate was arranged so that the surface on which the partition was formed faced the photomask so that it overlapped with the center of the hole of the photomask. While irradiating blue light, the two-dimensional spectral radiance was measured using a two-dimensional spectral radiance meter (SR-5000M, manufactured by Topcon Technohouse Co., Ltd.) from the side of the substrate on which no partition was formed. At this time, when the blue light luminance at the center of the unit cell above the hole in the photomask is set to 100, the distance to the lower position in the direction parallel to the stripe where the luminance is 1 or less is measured, and the light diffusion in the vertical direction is evaluated. The criteria are A when the distance is less than 150 μm (that is, when it is within the unit cell), B when it is 150 μm or more and less than 200 μm, C when it is 200 μm or more and less than 250 μm, and D when it is 250 μm or more and less than 300 μm. , 300 .mu.m or more. In the case of E, since the center of the sub-pixels adjacent in the direction parallel to the stripe emits light with a certain brightness or more, the light diffusion is large, which is not suitable.

(Evaluation method for mixed colors)
For the wavelength conversion substrate prepared for evaluation of vertical light diffusion, light from a blue light source was passed through a photomask to form a wavelength conversion layer for green subpixels in the same manner as when evaluating vertical light diffusion. The center of the unit cell was irradiated, and the two-dimensional spectral radiance was measured using SR-5000M. At this time, the relative value of the red light luminance in the adjacent red sub-pixel wavelength conversion layer was measured when the green light luminance at the center of the unit lattice above the hole in the photomask was set to 100. The evaluation criteria for color mixture were A when the red light luminance was below the detection limit and not observed, C when the red light luminance was less than 1, and E when it was 1 or more. In the case of E, the light of a color other than the original emission color is emitted with a brightness higher than a certain level, which is not suitable.

(Evaluation results)
Evaluation results are shown in Tables 1 and 2. All of Examples 1 to 18 were good. Comparative Example 1, which has a large aperture ratio, is not suitable because both the vertical light diffusion and the color mixture are remarkable due to the large usage rate of the wavelength conversion material and the thin partition wall width. In Comparative Example 2, in which the width of the horizontal barrier ribs was large, the top of the horizontal barrier ribs was conspicuous, and the flow direction and degree of flow were random. . Comparative Examples 3 and 4, which had large aperture ratios, were unsuitable because they used a large amount of wavelength conversion material and caused significant vertical light diffusion or color mixture. Comparative Example 5, in which W _max /W _min was less than 2, was not suitable due to significant vertical light diffusion.

Reference Signs List 1 Partition 2 Opening 3 Substrate 4 Coating head 5 Paste 6 Pressure pipe 7 Discharge port 8 Wavelength conversion layer

Claims (5)

A wavelength conversion substrate having a wavelength conversion layer in openings of a substrate and a substrate with partitions having partitions, wherein the openings partitioned by the partitions are stripe-shaped, and the aperture ratio of the openings is 60% or less. , the opening has a structure in which a portion with a large opening width and a portion with a small opening width are repeated in a direction parallel to the stripe, and the maximum value W _max and the minimum value W _min of the opening width in the repeating unit of the repeating structure is a wavelength conversion substrate that satisfies the following relational expression (1).
_Wmax / _Wmin ≧2 (1) 2. The wavelength conversion substrate according to claim 1, wherein the opening in the repeating unit satisfies the following relational expression at least at one or more locations where W is the width of the opening at any one location.
_Wmax >W> _Wmin (2) Regarding the opening, for any two opening widths between the location where the opening width is the maximum value W _max and the location where the opening width is the minimum value W _min , the side closer to W _max 3. The wavelength conversion substrate according to claim 2, wherein the following relational expression is satisfied at all points, where W _{a is the width of the opening and W b is} the side closer to W _min .
W _max >W _a >W _b >W _min (3) A display comprising the wavelength conversion substrate according to any one of claims 1 to 3 and an OLED or LED as a light source. A method for manufacturing a wavelength conversion substrate having a wavelength conversion layer in an opening of a substrate and a substrate with partitions, wherein the openings partitioned by the partitions have a stripe shape and an aperture ratio of the openings is 60% or less. and the opening has a structure in which a portion with a large opening width and a portion with a small opening width are repeated in a direction parallel to the stripe, and the maximum value W _max and the minimum value W of the opening width in the repeating unit of the repeating structure. A method of manufacturing a wavelength conversion substrate, comprising applying a wavelength conversion paste to the opening of the wavelength conversion substrate with a nozzle so that _min satisfies the following relational expression.
_Wmax / _Wmin ≧2 (1)

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