CN114981690A

CN114981690A - Method for manufacturing wavelength conversion substrate, and display

Info

Publication number: CN114981690A
Application number: CN202180009884.5A
Authority: CN
Inventors: 谷野贵广; 梶野佳范; 石冢雅敏
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 2020-02-13
Filing date: 2021-02-10
Publication date: 2022-08-30
Also published as: KR20220137867A; WO2021162024A1; JPWO2021162024A1

Abstract

A method for manufacturing a wavelength conversion substrate having a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, wherein an opening of the partition wall is in a stripe shape, the light-shielding layer has a structure in which the opening and the light-shielding portion are overlapped in the stripe direction in 1 stripe of the stripe shape, the aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%, and the method for manufacturing the wavelength conversion substrate has a step of applying a nozzle coating to a wavelength conversion paste so that the opening of the light-shielding layer and the light-shielding portion of the light-shielding layer have the same composition in the 1 stripe. Provided are a wavelength conversion substrate, a display using the same, and a method for manufacturing the wavelength conversion substrate, wherein a wavelength conversion layer is easily formed and light diffusion to adjacent sub-pixels is suppressed.

Description

Method for manufacturing wavelength conversion substrate, and display

Technical Field

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

Background

In recent years, with the development of information terminal devices such as smart phones and tablet personal computers and the high definition of flat panel displays such as televisions, the demand for higher performance of the displays has been further increased. Among them, wavelength-conversion-type Organic Light Emitting Diode (OLED) displays and Light Emitting Diode (LED) displays are attracting attention as high-performance displays. These displays are of a type in which an active matrix-driven OLED or LED is used as a light source, and full-color display is performed by changing at least a part of light using 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 emitting blue light is known (patent document 1). In this case, the light from the OLED is transmitted and scattered without being wavelength-converted in the blue sub-pixel, and the blue light from the OLED is converted into green and red colors by the wavelength conversion material in the green and red sub-pixels, respectively.

As a method of using an LED as a light source, a method of using an LED that emits blue light as in the case of an OLED and changing a part of light into red and green by a wavelength conversion material is known; and a system in which an LED emitting ultraviolet light is used and the LED is discolored to blue, green, or red by a wavelength conversion material (patent document 2).

In these wavelength conversion displays, it is necessary to pattern and arrange the wavelength conversion material in a cell partitioned by a partition wall of a substrate on which the partition wall is formed in a size corresponding to a sub-pixel of an OLED or an LED as a light source. As a method for patterning a wavelength conversion material, a photolithography method and an inkjet method are known (patent document 3).

Documents of the prior art

Patent literature

Patent document 1: japanese Kohyo publication No. 2006-501617

Patent document 2: japanese examined patent publication 2016 No. 523450

Patent document 3: international publication No. 2018/123103

Disclosure of Invention

Problems to be solved by the invention

However, in the photolithography method, a wavelength conversion material is applied to the entire surface, a predetermined position is exposed, and then most of the wavelength conversion material is removed by development, and therefore, there are the following problems: the wavelength conversion material is highly worn, and the process is complicated, and it is necessary to repeat exposure and development many times. Further, the inkjet method is excellent in material efficiency because a wavelength conversion layer can be formed only at a desired position, but when an ink containing a wavelength conversion material is applied by inkjet, it is necessary to design the viscosity of the ink to be low, and therefore there is a problem that particle components such as the wavelength conversion material settle in the ink and easily clog an inkjet nozzle.

On the other hand, as a method of applying the paste, a nozzle application method is known in which the paste is continuously discharged from a discharge port of an application head while moving the position of the application head relative to the substrate to apply the paste. Fig. 1 shows a schematic diagram illustrating an example of a method of applying a wavelength conversion paste by a nozzle application method using an application head having a plurality of discharge ports. The coating method comprises the following steps: the coating head 4 has a space (manifold) for storing the paste 5 therein, and is moved toward and relative to the substrate 3, and compressed air with controlled pressure is introduced through a pressure pipe 6 connected to the space, and the paste 5 is discharged from a discharge port 7 to be coated. In the nozzle coating method, since the viscosity of the paste can be higher than that in the ink jet method, clogging of the nozzle due to sedimentation of the particle component can be suppressed by setting the viscosity to be high.

However, in the nozzle coating method, the paste is applied while being continuously discharged, and thus the paste is applied in a stripe shape. Here, when a straight line shape having a uniform opening width is formed in a direction parallel to the stripe as a partition wall shape suitable for the nozzle coating method, there is a problem that light leakage occurs significantly in sub-pixels adjacent to each other in the direction parallel to the stripe. In addition, when the lattice shape is formed, there are also problems as follows: when the bank width of the bank in the direction orthogonal to the stripe (hereinafter, referred to as a horizontal bank) is narrow, light leakage occurs to the sub-pixels adjacent in the direction parallel to the stripe, as in the stripe shape; when wider, the paste spans over the partition walls. In any of the above cases, when the width of the partition wall in the direction parallel to the stripe is narrow, light leaks to the sub-pixels of the openings adjacent in the direction orthogonal to the stripe, and a color mixture occurs.

Therefore, an object of the present invention is to provide a wavelength conversion substrate in which a wavelength conversion layer can be easily formed and light diffusion to adjacent sub-pixels can be suppressed.

Means for solving the problems

In order to solve the above problem, a method for manufacturing a wavelength conversion substrate according to the present invention has any one of the following configurations.

That is, the method for manufacturing a wavelength conversion substrate of the present invention is a method for manufacturing a wavelength conversion substrate including a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, wherein an opening portion of the partition wall is in a stripe shape, the light-shielding layer has a structure in which the opening portion and the light-shielding portion are overlapped in a stripe direction in 1 stripe of the stripe shape, and an aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%, and the method for manufacturing includes a step of applying a nozzle to a wavelength conversion paste so that the opening portion of the light-shielding layer and the light-shielding portion of the light-shielding layer have the same composition in the 1 stripe.

Alternatively, the method for manufacturing a wavelength conversion substrate of the present invention is a method for manufacturing a wavelength conversion substrate including a substrate, a light shielding layer, a partition wall, and a wavelength conversion layer, the openings of the partition are in the form of a stripe, and the openings of the partition have a structure in which at least 2 or more kinds of patterns are repeated in the stripe direction in 1 stripe of the stripe, in at least 1 of the repeating patterns, the light-shielding layer has an opening at the opening of the partition, and, in at least 1 of the repeating patterns, the light shielding layer has substantially no opening at the opening of the partition wall, the method further includes a step of applying a wavelength conversion paste to the opening of the wavelength conversion substrate by a nozzle so that the wavelength conversion layer has the same composition at both the portion of the light-shielding layer having the opening in the opening of the partition wall and the portion of the light-shielding layer having no opening in the opening of the partition wall.

The wavelength conversion substrate of the present invention has any one of the following configurations.

That is, the wavelength conversion substrate of the present invention is a wavelength conversion substrate having a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, an opening portion of the partition wall is in a stripe shape, the light-shielding layer has a structure in which the opening portion and the light-shielding layer are repeated in the stripe direction in 1 stripe of the stripe shape, an aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%, and the wavelength conversion layer has the same composition in both the opening portion of the light-shielding layer and the light-shielding portion of the light-shielding layer in the 1 stripe.

Alternatively, a wavelength conversion substrate of the present invention is a wavelength conversion substrate having a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, wherein an opening of the partition wall is in a stripe shape, and in 1 stripe of the stripe shape, the opening of the partition wall has a structure in which at least 2 or more kinds of patterns are repeated in the stripe direction, and in at least 1 of the repeated patterns, the light-shielding layer also has an opening in the opening of the partition wall, and in at least 1 of the repeated patterns, the light-shielding layer does not substantially have an opening in the opening of the partition wall, and a portion of the light-shielding layer having an opening in the opening of the partition wall and a portion of the light-shielding layer having no opening in the opening of the partition wall both have the same composition of the wavelength conversion layer.

The display of the present invention has the following configuration.

That is, the display of the present invention is a display having the wavelength conversion substrate and an OLED or LED as a light source.

In the method for manufacturing a wavelength conversion substrate according to the present invention, it is preferable that the at least 1 stripe has an aperture ratio of the partition walls of 50 to 95%.

In the method of manufacturing a wavelength conversion substrate according to the present invention, it is preferable that the thickness H of the partition wall and the thickness T of the light shielding layer are equal to each other ₁ And thickness T of the wavelength conversion layer ₂ Satisfies the following formulae (1) and (2).

H/100≤T ₁ ≤H/3 (1)

H/2≤T ₂ ≤H (2)

In the method of manufacturing a wavelength conversion substrate according to the present invention, it is preferable that a planarization layer is further provided between the partition wall and the light shielding layer.

In the method for producing a wavelength conversion substrate of the present invention, the wavelength conversion layer preferably contains a resin.

In the method for manufacturing a wavelength conversion substrate of the present invention, the porosity of the wavelength conversion layer is preferably 0.01 to 10%.

In the method for manufacturing a wavelength conversion substrate of the present invention, the light-shielding layer preferably has a reflectance of 0.1 to 10%.

In the method for producing a wavelength conversion substrate of the present invention, the wavelength conversion layer preferably contains an inorganic phosphor.

In the method for manufacturing a wavelength conversion substrate according to the present invention, the wavelength conversion layer preferably contains quantum dots.

ADVANTAGEOUS EFFECTS OF INVENTION

The method for manufacturing a wavelength conversion substrate according to the present invention can provide a wavelength conversion substrate in which a wavelength conversion layer can be easily formed and light diffusion to adjacent sub-pixels can be suppressed.

Drawings

FIG. 1 is a schematic view showing a paste application method by a nozzle application method.

FIG. 2 is a plan view showing an embodiment of a light-shielding layer.

FIG. 3 is a plan view showing an embodiment of a partition wall.

FIG. 4 is a plan view showing an embodiment of a substrate with a partition wall.

FIG. 5 is a plan view showing an embodiment of a wavelength conversion substrate of the present invention in which a wavelength conversion layer is formed on the substrate with partition walls shown in FIG. 4.

FIG. 6 is a cross-sectional view A-A' of the wavelength converting substrate shown in FIG. 5.

FIG. 7 is a B-B' cross-sectional view of the wavelength converting substrate shown in FIG. 5.

FIG. 8 is a plan view showing an embodiment of a partition wall.

FIG. 9 is a plan view showing an embodiment of a light-shielding layer.

FIG. 10 is a plan view showing an embodiment of a partition wall.

FIG. 11 is a plan view showing an embodiment of a partition wall.

FIG. 12 is a plan view showing an embodiment of a partition wall.

FIG. 13 is a plan view showing an embodiment of a partition wall.

FIG. 14 is a plan view showing an embodiment of a light-shielding layer.

Detailed Description

The method for manufacturing a wavelength conversion substrate of the present invention includes a step of applying a wavelength conversion paste to a nozzle so as to have a wavelength conversion layer in an opening of a partition wall of a substrate with a partition wall, the substrate, a light shielding layer, and the partition wall.

In the present invention, the substrate functions as a support in the substrate with the partition wall. Examples of the substrate include a glass plate, a resin plate, and a resin film. As the material of the glass plate, alkali-free glass is preferable. As materials of the resin plate and the resin film, polyester, (meth) acrylic polymer, transparent polyimide, polyether sulfone, and the like are preferable. The thickness of the glass plate and the resin plate is preferably 1mm or less, and preferably 0.8mm or less. The thickness of the resin film is preferably 100 μm or less.

In the present invention, the substrate with the barrier ribs has a light shielding layer on the substrate. In the present invention, a portion of the surface of the substrate on the side having the light-shielding layer, which is defined by the light-shielding layer and on which the light-shielding layer is not formed, is referred to as an opening of the light-shielding layer. The portion where the light-shielding layer is formed is referred to as a light-shielding portion of the light-shielding layer.

In the present invention, the light-shielding layer preferably absorbs visible light. By absorbing visible light, light emitted from the OLED or LED, or light converted by a wavelength conversion material described later, can be transmitted through the light shielding portion of the light shielding layer, thereby suppressing blurring of the light emitting point. In addition, since the light-shielding layer absorbs visible light, reflected light when the display is irradiated with external light can be suppressed, and thus the contrast of the display appearance is improved. Further, as described later, light leakage to sub-pixels adjacent in a direction parallel to the stripe can be suppressed. When the LED is an ultraviolet light emitting LED, it is preferable that the LED absorbs ultraviolet light in addition to visible light.

The light-shielding layer of the present invention preferably contains a black pigment. The black pigment is not particularly limited, and examples thereof include a black pigment such as carbon black, titanium black, chromium oxide, iron oxide, aniline black, perylene pigment, and c.i. solvent black (solvent black)123, an inorganic black pigment such as resin-coated carbon black, a composite oxide of titanium, manganese, iron, copper, or cobalt, and a combination of an organic pigment and a black pigment.

The light-shielding layer of the present invention preferably has an Optical Density (OD) value of 2 or more, more preferably 3 or more at a wavelength of 550 nm.

In the present invention, the substrate with a partition has a partition on the substrate. In the present invention, a portion of the substrate on the side having the partition walls, which is defined by the partition walls and on which no partition wall is formed, is referred to as an opening of the partition wall.

In the present invention, the opening defined by the partition wall has a stripe shape. The ribbon shape means a shape in which substantially linear openings are continuous or repeated in a direction parallel to the linear direction. Since the openings are in the form of stripes, the wavelength conversion layer can be easily formed by a nozzle coating method. The substantially straight line shape is not limited to a completely straight line shape, and may be bent or deviated in a direction orthogonal to the straight line direction within a range not intersecting with the center line of the opening of the adjacent strip shape. The substantially linear opening may be continuous or discontinuous with a transverse wall. The shape of the opening is not particularly limited, and examples thereof include a square shape, a circular shape, and an elliptical shape. In the present invention, the stripe direction or the direction parallel to the stripe refers to a direction parallel to the linear direction.

The partition wall preferably has a function of preventing light from passing from a certain sub-pixel to an adjacent sub-pixel. By having this function, color mixing due to light leakage to adjacent sub-pixels can be suppressed.

Fig. 2 is a plan view of an embodiment of the light-shielding layer, and fig. 3 is a plan view of an embodiment of the partition wall. Fig. 4 is a plan view of an embodiment of a substrate with partitions in which the partitions in fig. 3 are formed on the substrate on which the light-shielding layer in fig. 2 is formed. Fig. 5 is a plan view of an embodiment of the wavelength conversion substrate of the present invention in which a wavelength conversion layer is formed on the substrate with the partition wall shown in fig. 4. Fig. 6 and 7 are cross-sectional views a-a 'and B-B' as examples of cross-sectional views in a direction orthogonal to the stripe direction in the wavelength conversion substrate of fig. 5. The substrate 3 has a light-shielding layer 8 and a partition wall 1 formed with a pattern thereon, and has a wavelength conversion layer 9 in an opening defined by the partition wall.

In one embodiment of the present invention, it is necessary that: the openings of the partition walls are in a stripe shape, the light-shielding layer has a structure in which the openings and the light-shielding portions overlap in the stripe direction in 1 stripe of the stripe, and the aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%. Here, the aperture ratio of the light-shielding layer in 1 stripe means a ratio of an area of a portion where the light-shielding portion is not formed in 1 repeating unit of the light-shielding layer having a structure in which the opening portion and the light-shielding portion are repeated in the stripe direction, divided by a total area of the 1 repeating unit. When the aperture ratio of the light-shielding layer is less than 5%, the luminance of the display may decrease. When the aperture ratio of the light-shielding layer is greater than 70%, light leakage may occur significantly in the sub-pixels adjacent to each other in the direction parallel to the stripe.

In the present invention, the opening ratio of the partition wall is preferably 50 to 95%. Here, the aperture ratio of the partition wall is a ratio of an area of the partition wall forming portion in the display region of the display divided by a total area of the display region of the display. When the aperture ratio is less than 50%, the paste may easily spread over the top of the partition wall when the wavelength conversion paste is nozzle-coated. When the aperture ratio is larger than 95%, light may easily leak to pixels adjacent to each other in a direction perpendicular to the stripe direction.

In the present invention, the openings of the partition walls may be continuous in a direction parallel to the strip, or may be discontinuous with the horizontal partition walls. When the barrier ribs have a function of preventing transmission and scattering of light, the transverse barrier ribs suppress scattering of light in a direction parallel to the stripe. However, when the partition walls of the lateral partition walls are wide, there may be a portion of the wavelength conversion layer formed by the nozzle coating method on the lateral partition walls, and therefore the ratio of the length of the opening in the direction parallel to the strip with respect to the length of the repeating unit in the direction parallel to the strip is preferably 80% or more. More preferably 90% or more.

The partition wall preferably has a reflectance of 20 to 90% when the thickness is 10 μm at a wavelength of 550 nm. By setting the reflectance to 20% or more, the luminance of the display can be improved by reflection from the side surfaces of the partition walls. On the other hand, the reflectance is preferably 90% or less from the viewpoint of improving the formation accuracy of the partition wall pattern. Here, the thickness of the partition wall means the length of the partition wall in the direction perpendicular to the substrate (height direction). In the case of the substrate with partition walls shown in fig. 6 and 7, the thickness of the partition wall 1 is denoted by reference numeral H. The length of the partition in the horizontal direction on the substrate is the width of the partition. In the case of the substrate with partition walls shown in fig. 6 and 7, the width of the partition wall 1 is denoted by a symbol L. In FIG. 3, the direction parallel to the strip is indicated by an upward arrow (the same applies to FIGS. 8, 10 to 13).

The thickness of the partition wall is preferably larger than the thickness of the cured wavelength conversion paste when the cured wavelength conversion paste is present in the cell of the substrate with the partition wall. Specifically, the thickness of the partition wall 1 is preferably 0.5 μm or more, and more preferably 5 μm or more. On the other hand, from the viewpoint of more efficiently extracting light emission from the bottom of the layer containing the color conversion luminescent material, the thickness of the partition wall is preferably 100 μm or less, more preferably 70 μm or less, and still more preferably 50 μm or less. The width of the partition wall may be sufficient to improve the luminance by reflection of light on the side surface of the partition wall and to suppress color mixing of light emitted from a cured product of the adjacent wavelength converting paste due to light leakage. Specifically, the width of the partition wall is preferably 5 μm or more, and more preferably 10 μm or more.

In the present invention, the width of the opening of the partition in the direction perpendicular to the tape is referred to as the width of the opening of the partition. In one embodiment of the present invention, it is necessary that the shape of the partition walls has a portion where the width of the opening of the partition walls is large, a portion where the width of the opening of the partition walls is small, or a portion where the lateral partition walls are present, and a structure in which the portion where the width of the opening is changed or 2 or more kinds of patterns partitioned by the lateral partition walls are repeated in a direction parallel to the strip. In addition, it is necessary that the light shielding layer has an opening at the opening of the partition in at least 1 of the above-described repeated patterns of the partition, and the light shielding layer does not substantially have an opening at the opening of the partition in at least 1 of the other repeated patterns. Here, "substantially not having an opening" means that a defect such as a pinhole of the light-shielding layer, or a minute opening of the light-shielding layer at the end of the repeating unit due to misalignment between the partition wall and the light-shielding layer may be present. With such a configuration, when the OLED or LED is disposed and emits light at a position corresponding to the opening of the light-shielding layer, light emitted from the OLED or LED and light converted by the wavelength conversion layer described later are reflected by the partition wall and concentrated at a position where the opening of the light-shielding layer is present.

In the present invention, it is preferable that, between adjacent stripes, portions where the light-shielding layer has openings also in the openings of the partition walls are arranged in a staggered pattern. In such a configuration, the partition width in the direction perpendicular to the bands is increased, and therefore color mixture can be effectively suppressed.

In one embodiment of the present invention, it is essential that the light-shielding layer has a structure in which an opening portion and a light-shielding portion are overlapped in a stripe direction of the partition wall, and in the 1 stripe, both the opening portion of the light-shielding layer and the light-shielding portion of the light-shielding layer have the same composition of the wavelength conversion layer. In one embodiment of the present invention, it is necessary that the light-shielding layer has openings of at least 1 pattern partition walls having openings at the openings of the partition walls and the light-shielding layer has openings of at least 1 pattern partition walls having no openings at the openings of the partition walls, both having the same composition as the wavelength conversion layer. With this configuration, light absorbed by the wavelength conversion layer and light scattered by the wavelength conversion layer are absorbed by the light-shielding layer at the light-shielding portion of the light-shielding layer and at a portion of the light-shielding layer not having the opening, so that diffusion of light in a direction parallel to the stripe is suppressed, and light leakage to sub-pixels adjacent in the direction parallel to the stripe can be effectively suppressed. In the method for manufacturing a wavelength conversion substrate according to the present invention, since the wavelength conversion layer is formed also on the light-shielding portion of the light-shielding layer and the portion of the light-shielding layer not having the opening by applying the wavelength conversion paste to the nozzle, the wavelength conversion layer can be easily formed, and an effect of suppressing light diffusion to the adjacent sub-pixels can be obtained.

It should be noted that the following situations do not exist: the wavelength conversion layer spans to the top of the partition wall; the light-shielding portion of the light-shielding layer has a wavelength conversion layer in a portion where a partition is provided between the light-shielding portion of the light-shielding layer and the wavelength conversion layer.

In the present invention, the wavelength conversion layer contains a wavelength conversion material. In the present invention, the wavelength conversion material is a material having wavelength conversion properties that absorbs electromagnetic waves and emits electromagnetic waves having a wavelength different from that of the absorbed electromagnetic waves. A full color display can be manufactured by patterning and coating a wavelength conversion paste having a wavelength conversion material to manufacture a wavelength conversion substrate, and combining the wavelength conversion substrate with an OLED light source and an LED light source.

As the wavelength conversion material, an inorganic phosphor and/or an organic phosphor is preferably used. For example, in the case of a display in which an OLED emitting blue light and a wavelength conversion substrate are combined, a red phosphor that emits red fluorescence by excitation with blue excitation light is preferably used as a wavelength conversion material in a region corresponding to a red subpixel; in the region corresponding to the green sub-pixel, a green phosphor that emits green fluorescence by excitation with blue excitation light is preferably used as the wavelength conversion material; in the region corresponding to the blue sub-pixel, preferably no wavelength converting material is used. Similarly, the wavelength conversion substrate of the present invention can be used for a display of a type using a blue LED or an ultraviolet light emitting LED corresponding to each sub-pixel as a backlight. The ON/OFF of light emission of each sub-pixel can be realized by active matrix driving of an OLED or an LED.

The inorganic phosphor emits light of various colors such as green and red. Examples of the inorganic phosphor include inorganic phosphors that emit light having a peak in a region of 500 to 700nm when excited by excitation light having a wavelength of 400 to 500nm, inorganic semiconductor fine particles called quantum dots, and the like. Examples of the former inorganic phosphor include spherical and columnar shapes. Examples of the inorganic phosphor include YAG phosphor, TAG phosphor, sialon phosphor, and Mn ⁴⁺ Activating a fluoride complex phosphor, and the like. These may be used in 2 or more kinds.

Among these inorganic phosphors, quantum dots are preferable. The quantum dot has a sharper peak in an emission spectrum than other phosphors, and thus can improve color reproducibility of a display.

Examples of the material of the quantum dot include group II-IV, group III-V, group IV-VI, group IV semiconductors, and the like. Examples of the inorganic semiconductor include Si, Ge, Sn, Se, and 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, Si, Al, Si, Se, CdSe, SnSe, CdSe, and other components of the same as carrier for the same as a carrier for the carrier of the carrier ₃ N ₄ 、Ge ₃ N ₄ 、Al ₂ O ₃ And the like. These may be used in 2 or more kinds.

The quantum dots may contain a p-type dopant or an n-type dopant. In addition, the quantum dot may have a core-shell structure. In the core-shell structure, any appropriate functional layer (single layer or multilayer) may be formed around the shell according to the purpose, or the surface of the shell may be subjected to surface treatment and/or chemical modification.

Examples of the shape of the quantum dot include a spherical shape, a columnar shape, a scaly shape, a plate shape, and an amorphous shape. The average particle diameter of the quantum dots can be selected according to the desired emission wavelength, and is preferably 1 to 30 nm. When the average particle diameter of the quantum dot is 1 to 10nm, the peak in the emission spectrum can be made sharper in each of blue, green and red colors. For example, in the case where the average particle diameter of the quantum dots is about 2nm, blue light is emitted; green light is emitted when the average particle diameter of the quantum dots is about 3 nm; when the average particle diameter of the quantum dot is about 6nm, red light is emitted. The average particle diameter of the quantum dots is preferably 2nm or more, and preferably 8nm or less. The average particle size of the quantum dots can be determined by dynamic light scattering. Examples of the measurement device for the average particle diameter include a dynamic light scattering photometer DLS-8000 (available from Otsuka electronics Co., Ltd.).

Examples of the organic phosphor include a phosphor that emits red fluorescence by excitation with blue excitation light, and a pyrromethene derivative having a basic skeleton represented by the following structural formula (a); examples of the phosphor which emits green fluorescence by excitation with blue excitation light include a pyrromethene derivative having a basic skeleton represented by the following structural formula (B). Further, perylene derivatives, porphyrin derivatives, oxazine derivatives, pyrazine derivatives, and the like, which emit red or green fluorescence by selection of substituents, may be mentioned. These may be contained in 2 or more kinds. Among these, the pyrromethene derivative is preferable because of its high quantum yield. The pyrromethene derivative can be obtained, for example, by the method described in Japanese patent application laid-open No. 2011-241160.

[ chemical formula 1]

Since the organic phosphor is soluble in a solvent, a layer containing a wavelength converting material can be easily formed to a desired thickness.

The wavelength conversion layer of the present invention may contain light scattering particles. By including the light scattering particles, the light path length can be increased by scattering blue light and ultraviolet light in the wavelength conversion layer, and the light conversion efficiency by the wavelength conversion material can be improved.

As the light scattering particles, any of barium sulfate, alumina, zirconia, zinc oxide, and titanium oxide is preferable. These light scattering particles may contain 2 or more kinds.

The refractive index of the light scattering particles at a wavelength of 587.5nm is preferably 1.60-2.70. By setting the refractive index of the light scattering particles to 1.60 or more, the scattering property of blue light or ultraviolet light in the wavelength conversion layer by the light scattering particles is improved, and the light conversion efficiency by the wavelength conversion material is easily improved. In addition, light scattered by the wavelength conversion layer is absorbed by the light shielding layer, so that the diffusion of light in a direction parallel to the stripe is suppressed, and light leakage to sub-pixels adjacent in the direction parallel to the stripe can be effectively suppressed. 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 the emitted light after wavelength conversion is easily extracted to the outside of the cell. When 2 or more kinds of light scattering particles are contained, it is preferable that at least 1 kind of light scattering particles have a refractive index 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 3% by weight or more, and still more preferably 5% by weight or more in the solid content. On the other hand, from the viewpoint of suppressing a decrease in the light emission efficiency due to concentration quenching of the wavelength converting material, the content of the light scattering particles is preferably 70% by weight or less, more preferably 60% by weight or less, and still more preferably 50% by weight or less in the solid content. The solid component herein refers to all components contained in the wavelength conversion paste except for volatile components such as a solvent. The amount of the solid component can be determined by heating the wavelength conversion paste at 150 ℃ for 1 hour and measuring the amount of the residual component after evaporation of the volatile component.

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 converting paste is not particularly limited, and examples thereof include a method of curing a wavelength converting paste containing a polymerizable compound by heat or light; a method of heating to volatilize the solvent from the wavelength converting paste containing the solvent to cure the paste; and the like.

In the present invention, the wavelength converting paste may contain a monomer as the polymerizable compound. The monomer in the present invention is a compound which is polymerized by an active species generated by a reaction of a polymerization initiator described later.

The monomer in the present invention is preferably a compound having an ethylenically unsaturated double bond in the molecule. The monomer preferably has 2 or more ethylenically unsaturated double bonds in the molecule. In view of ease of radical polymerization, the monomer preferably has a (meth) acryloyl group (Japanese (メタ) アクリル group). In addition, from the viewpoint of further improving the sensitivity in pattern processing, the double bond equivalent of the monomer is preferably 400g/mol or less.

Examples of the monomer 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, 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 dimethacrylate, 1, 6-hexanediol diacrylate, and the like, 1, 9-nonanediol dimethacrylate, 1, 10-decanediol dimethacrylate, dimethylol-tricyclodecane diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripentaerythritol heptaacrylate, tripentaerythritol octaacrylate, tetrapentaerythritol nonaacrylate, tetrapentaerythritol decaacrylate, pentapentaerythritol undecanoate, pentapentaerythritol dodecaacrylate, tripentaerythritol heptamethacrylate, tripentaerythritol octamethacrylate, tetrapentaerythritol nonamethacrylate, tetrapentaerythritol decamethacrylate, pentapentaerythritol undecamrylate, pentapentaerythritol dodecamethacrylate, pentapentaerythritol tetraacrylate, pentaacrylate, and the like, Dimethylol-tricyclodecane diacrylate and the like. These monomers may contain 2 or more species.

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

In the present invention, the wavelength converting paste may contain a polymerization initiator. The wavelength conversion paste can be cured by containing a polymerization initiator and a monomer, reacting the polymerization initiator by light irradiation, heating, or the like, and allowing the monomer to progress in polymerization by an active species generated from the polymerization initiator.

The polymerization initiator may be any of radical initiators and cationic initiators, i.e., polymerization initiators that react with light (including ultraviolet rays and electron beams) or heat to generate active species such as radicals and cations. Of these, radical initiators are preferred. Examples of the polymerization initiator include α -aminoalkylphenone compounds such as 2-methyl- [4- (methylthio) phenyl ] -2-morpholinopropan-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one, and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; acylphosphine oxide compounds such as 2, 4, 6-trimethylbenzoylphenylphosphine oxide, bis (2, 4, 6-trimethylbenzoyl) -phenylphosphine oxide, bis (2, 6-dimethoxybenzoyl) - (2, 4, 4-trimethylpentyl) -phosphine oxide, and the like; oxime ester compounds such as 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-butanedione-2- (O-methoxycarbonyl) oxime, 1, 3-diphenylpropanetrione-2- (O-ethoxycarbonyl) oxime, and ethanone-1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] -1- (O-acetyl oxime); benzyl ketal compounds such as benzyl dimethyl ketal; α -hydroxyketone compounds such as 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) one, and 1-hydroxycyclohexyl-phenylketone; benzophenone compounds such as 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, and 3, 3 ', 4, 4 ' -tetrakis (t-butylperoxycarbonyl) benzophenone; acetophenone compounds such as 2, 2-diethoxyacetophenone, 2, 3-diethoxyacetophenone, 4-tert-butyldichloroacetophenone, benzylideneacetophenone and 4-azidobenzylideneacetophenone; aromatic ketone ester compounds such as methyl 2-phenyl-2-oxoacetate; benzoic acid ester compounds such as ethyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, ethyl 4-diethylaminobenzoate and methyl 2-benzoylbenzoate; and the like. These polymerization initiators may contain 2 or more species.

In the present invention, the wavelength converting paste preferably contains an acylphosphine oxide polymerization initiator such as 2, 4, 6-trimethylbenzoylphenylphosphine oxide, bis (2, 4, 6-trimethylbenzoyl) -phenylphosphine oxide, bis (2, 6-dimethoxybenzoyl) - (2, 4, 4-trimethylpentyl) -phosphine oxide, or the like, because coloring due to the polymerization initiator is suppressed.

In the present invention, the content of the polymerization initiator in the wavelength converting paste is preferably 0.01% by weight or more, more preferably 0.1% by weight or more in terms of solid content, from the viewpoint of efficiently performing 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 in the solid content, from the viewpoint of suppressing elution of the residual polymerization initiator and the like and further improving yellowing.

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

In the present invention, when the wavelength converting paste contains a polymer, examples of the polymer include silicone resins such as polyvinyl acetate, polyvinyl alcohol, ethyl cellulose, methyl cellulose, polyethylene, polymethylsiloxane, polymethylphenylsiloxane, and the like, polystyrene, butadiene/styrene copolymers, polystyrene, polyvinylpyrrolidone, polyamides, high molecular weight polyethers, copolymers of ethylene oxide and propylene oxide, polyacrylamides, acrylic resins, and the like.

In the present invention, when a solvent is contained in the wavelength conversion paste, examples of the solvent include alcohols such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, tert-butanol, pentanol, 4-methyl-2-pentanol, 3-methyl-2-butanol, 3-methyl-3-methoxy-1-butanol, and diacetone alcohol; glycols such as ethylene glycol and propylene glycol; ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol 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, and the like; ketones such as methyl ethyl ketone, acetylacetone, methyl propyl ketone, methyl butyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, and 2-heptanone; amides such as dimethylformamide and dimethylacetamide; acetates such as ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl lactate, ethyl lactate, and butyl lactate; aromatic or aliphatic hydrocarbons such as toluene, xylene, hexane, and cyclohexane; gamma-butyrolactone, N-methyl-2-pyrrolidone, dimethyl sulfoxide, and the like.

In the present invention, the viscosity of the wavelength conversion paste was measured for 1sec when a Plate P35 Ti L manufactured by the same company was attached to a rheometer (HAAKE MARS; manufactured by Thermo Fisher Scientific Co., Ltd.) and the gap was set to 200 μm ^-1 The viscosity at the shear rate of (3) is preferably 1,000 to 500,000 mPas. When the viscosity is 1,000mPa · s or more, the particle components such as the light-scattering particles are less likely to settle even when stored for a long period of time after the paste is produced. The viscosity is more preferably 3,000 mPas or more, and still more preferably 5,000 mPas or more. Further, when the viscosity is 500,000mPa · s or less, the composition can be easily and stably discharged even when pressurized with low-pressure compressed air. The viscosity is more preferably 400,000 mPas or less, and still more preferably 300,000 mPas or less.

In the present invention, when a dispersant is contained in the wavelength conversion paste, preferable examples of the dispersant include "Disperbyk" (registered trademark) 106, 108, 110, 180, 190, 2001, 2155, 140, and 145 (the above are commercial numbers, manufactured by Big Chemie corporation).

In the present invention, the thickness H of the partition wall and the thickness T of the light shielding layer ₁ And thickness T of wavelength conversion layer ₂ Preferably, the following formulas (1) and (2) are satisfied.

H/100≤T ₁ ≤H/3 (1)

H/2≤T ₂ ≤H (2)

(1) In, H/100 > T ₁ In this case, the light-shielding layer is thin and the light-shielding property is reduced. In addition, T ₁ When the ratio is more than H/3, the light-shielding layer is thick, and when light passes through the opening of the light-shielding layer, the light is absorbed by the side surface of the light-shielding layer, thereby reducing the luminance. (2) In which H/2 > T ₂ In this case, since the wavelength conversion layer is thin, light absorption and scattering are less likely to occur in the wavelength conversion layer, and light leakage to the sub-pixels adjacent in the direction parallel to the stripe is likely to occur. T is ₂ When H is greater, the wavelength conversion layer is more raised than the partition wall, and therefore, a gap is formed when the wavelength conversion substrate is bonded to the OLED substrate or the LED substrate, and light easily leaks to an adjacent cell.

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

In the present invention, when a blue OLED or a blue LED is used as the light source, it is preferable that a paste having the same composition as the wavelength conversion paste is nozzle-coated in the blue light-emitting sub-pixel, except that the wavelength conversion layer is not included. In particular, from the viewpoint of improving the viewing angle of the display, it is preferable to perform nozzle coating on the light scattering paste containing the light scattering particles. When the light scattering paste is formed by nozzle application, the light scattering paste is formed also in the light-shielding portion of the light-shielding layer and the portion of the light-shielding layer not having the opening, as in the case of the wavelength conversion layer, and therefore the light scattering paste is easily formed, and further, the light scattered in the light scattering layer is absorbed by the light-shielding layer, so that the diffusion of the light in the direction parallel to the stripe is suppressed, and the light leakage to the sub-pixels adjacent in the direction parallel to the stripe can be effectively suppressed.

Next, a display device of the present invention will be described. The display of the present invention has the wavelength conversion substrate and the light source. As the light source, a light source selected from a blue OLED, a blue LED, and an ultraviolet light emitting LED capable of active matrix driving is preferable.

The display of the present invention will be described by taking an example of a display having the wavelength conversion substrate of the present invention and a blue OLED. A photosensitive polyimide resin is applied to a glass substrate having a TFT pattern which can be driven by an active matrix, and an insulating film is formed by photolithography. After sputtering aluminum as a back electrode layer, patterning was performed by photolithography, and the back electrode layer was formed in an opening portion without an insulating film. Next, tris (8-hydroxyquinoline) aluminum (hereinafter abbreviated as Alq3) was formed as an electron transporting layer by a vacuum vapor deposition method, and then, as a light emitting layer, dicyanomethylenepyran, quinacridone, 4' -bis (2, 2-diphenylvinyl) biphenyl was doped into Alq3 to form a white light emitting layer. Then, N '-diphenyl-N, N' -bis (α -naphthyl) -1, 1 '-biphenyl-4, 4' -diamine was formed into a film by a vacuum evaporation method as a hole transport layer. Finally, ito (indium Tin oxide) was formed by sputtering to be a transparent electrode, thereby producing an OLED having a blue light-emitting layer. The OLED thus obtained was opposed to the wavelength conversion substrate and bonded with a sealant, thereby producing a display.

It should be noted that the wavelength conversion substrate of the present invention may have an OLED or an LED. In this case, a partition wall is formed on a substrate having an OLED or an LED, a wavelength conversion layer is formed, and a light-shielding layer is formed over the partition wall and the wavelength conversion layer.

The wavelength conversion substrate of the present invention preferably further includes a planarization layer between the partition wall and the light shielding layer. In particular, when the wavelength conversion substrate of the present invention has an OLED or an LED, it is preferable to form a light shielding layer uniformly by forming a partition wall on the substrate having the OLED or the LED, then forming a wavelength conversion layer and a flat layer, and then forming the light shielding layer on the flat layer, from the viewpoint of improving the contrast of the display.

In the present invention, the void ratio of the wavelength conversion layer is preferably 0.01 to 10%. In order to form a wavelength conversion layer with a low void ratio of less than 0.01%, it is generally necessary to increase the resin composition, and the content of the wavelength conversion material is relatively reduced. When the void ratio is more than 10%, light scattering in the wavelength conversion layer becomes excessive, and light extraction becomes difficult, resulting in a decrease in luminance. In particular, when the wavelength conversion substrate of the present invention has an OLED or an LED, if the light-shielding layer is formed over the wavelength conversion layer, the light-shielding layer may penetrate into the voids of the wavelength conversion layer, thereby enhancing light absorption.

Examples

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these ranges.

(method of measuring average particle diameter of light-scattering particles)

In a sample chamber filled with water of a particle size distribution measuring apparatus (MT 3300; manufactured by Nikkiso K.K.), light scattering particles were put, and after ultrasonic treatment for 300 seconds, the particle size distribution was measured, and the particle size at 50% to the cumulative distribution was defined as the average particle size.

(wavelength conversion paste, light scattering paste raw material)

The raw materials used for the preparation of the wavelength conversion paste are as follows.

Light scattering particles: AA-1.5 (alumina, average particle diameter 1.6 μm, alumina, product of Sumitomo chemical Co., Ltd.)

Wavelength converting material 1: lumidot 640 CdSe (Red Quantum dot Material, Sigma-Aldrich Co., Ltd.)

Wavelength converting material 2: lumidot 530 CdSe (Green Quantum dot Material, Sigma-Aldrich Co., Ltd.)

Photopolymerization initiator: "Irgacure" (registered trademark) OXE01 (manufactured by BASF Japan K.K.)

Monomer (b): NK-9PG (Polypropylene glycol #400 dimethacrylate as 2-functional methacrylate) (New Zhongcun chemical Co., Ltd.)

Polymer (b): "Etocell" (registered trademark) STD7(I) (cellulose ethyl ether) (manufactured by DDP Specialty Products Japan K.K.)

Solvent: propylene glycol monomethyl ether acetate (Fuji film and Guangdong Kabushiki Kaisha)

(preparation of wavelength conversion paste and light-Scattering paste)

After weighing 25 parts by weight of light-scattering particles, 5 parts by weight of wavelength conversion material 1, 0.1 part 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, kneading the mixture by a three-roll kneader, and then filtering the kneaded mixture by an SHP-400 filter (manufactured by ROKI techon corporation) while applying a pressure of 100 to 400kPa by air, a wavelength conversion paste for red subpixels was obtained. A wavelength converting paste for green sub-pixels was obtained in the same manner except that the wavelength converting material 1 was replaced with the wavelength converting material 2. In addition, a light-scattering paste for blue sub-pixels was obtained in the same manner except that the wavelength converting material 1 was not added.

(Synthesis of acrylic Polymer (P-1))

An acrylic polymer (P-1) powder having an average molecular weight (Mw) of 40,000 and an acid value of 110(mgKOH/g) was obtained by synthesizing a methyl methacrylate/methacrylic acid/styrene copolymer (mass ratio 30/40/30) by the method described in the literature (Japanese patent No. 3120476; example 1), adding 40 parts by weight of glycidyl methacrylate, reprecipitating with purified water, filtering and drying.

(preparation of Black pigment Dispersion)

A pot was charged with 200g of titanium nitride particles (manufactured by Nisshin Engineering Co., Ltd.) as a black pigment, 114g of a 35 wt% propylene glycol monomethyl ether acetate (hereinafter referred to as PGMEA) solution of an acrylic polymer (P-1), 25g of DISPERBYK LPN-21116 having a tertiary amino group and a quaternary ammonium salt as a polymer dispersant, and 661g of PGMEA, and the mixture was stirred with a homomixer for 20 minutes to obtain a predispersion. Then, the predispersion liquid was supplied to a container with 75% packing

Zirconia beads and an Ultra Apex Mill (manufactured by shou industries, Ltd.) equipped with a centrifugal separator were dispersed at a rotation speed of 8m/s for 3 hours to obtain a black pigment dispersion having a solid content concentration of 25 mass% and a coloring material/resin (mass ratio) of 80/20.

(preparation of resin composition for light-shielding layer)

33.31g of PGMEA was added with 0.35g of ADEKA ARKLS (registered trademark) NCI-831 as a photopolymerization initiator, and stirred until the solid content was dissolved. Then, 5.55g of a 35 wt% solution of PGMEA of the acrylic polymer (P-1), 2.81g of dipentaerythritol hexaacrylate (manufactured by Nippon chemical Co., Ltd.) as a polyfunctional monomer, 0.60g of KBM5103 (manufactured by shin-Etsu chemical Co., Ltd.) as an adhesion improving agent, and 0.40g of a10 wt% solution of PGMEA of a silicone surfactant BYK333 as a surfactant were added thereto, and the mixture was stirred at room temperature for 1 hour to obtain a photosensitive resist. To this photosensitive resist, 56.98g of a black pigment dispersion was added to prepare a resin composition for a light-shielding layer, the total solid content concentration of which was 20% and the black pigment/resin (mass ratio) was 58/42.

(method of analyzing Silicone solution)

The solid content concentration of the polysiloxane solution was determined by the following method. 1.5g of the polysiloxane solution was weighed into an aluminum cup and heated at 250 ℃ for 30 minutes using a hot plate to evaporate the liquid components. The weight of the solid content remaining in the heated aluminum cup was weighed, and the solid content concentration of the polysiloxane solution was determined from the ratio to the weight before heating.

The weight average molecular weight of the polysiloxane was determined by the following method. GPC analysis was performed using a GPC analyzer (HLC-8220; manufactured by Tosoh corporation) using tetrahydrofuran as a mobile phase in accordance with JIS K7252-3 (2008/03/20), and the weight average molecular weight in terms of polystyrene was measured.

The content ratio of each repeating unit in the polysiloxane was determined by the following method. The polysiloxane solution was poured into a NMR sample tube made of "Teflon" (registered trade name) having a diameter of 10mm to conduct ²⁹ In the Si-NMR measurement, the content ratio of each repeating unit is calculated from the ratio of the integrated value of Si derived from a specific organosilane to the integrated value of the entire Si derived from the organosilane. ²⁹ The Si-NMR measurement conditions are as follows.

The device comprises the following steps: nuclear magnetic resonance device (JNM-GX270, manufactured by Japan electronic Co., Ltd.)

The measuring method comprises the following steps: gated decoupling method

Measurement of nuclear frequency: 53.6693MHz (C ²⁹ Si nucleus)

Spectral width: 20,000Hz

Pulse width: 12 mu s (45 degree pulse)

Pulse repetition time: 30.0 seconds

Solvent: acetone-d 6

Reference substance: tetramethylsilane

Measuring temperature: 23 deg.C

Sample rotation speed: 0.0Hz

(Synthesis of polysiloxane solution)

A1,000 mL three-necked flask was charged with 147.32g (0.675mol) of trifluoropropyltrimethoxysilane, 40.66g (0.175mol) of 3-methacryloxypropylmethyldimethoxysilane, 26.23g (0.10mol) of 3-trimethoxysilylpropylsuccinic anhydride, 12.32g (0.05mol) of 3- (3, 4-epoxycyclohexyl) propyltrimethoxysilane, 0.808g of dibutylhydroxytoluene, and 171.62g of PGMEA, and an aqueous phosphoric acid solution prepared by dissolving 2.265g (1.0 wt% with respect to the charged monomers) of phosphoric acid in 52.65g of water was added thereto over 30 minutes while stirring at room temperature. The flask was then immersed in a 70 ℃ oil bath and stirred for 90 minutes, after which the oil bath was warmed to 115 ℃ over 30 minutes. 1 hour after the start of the temperature rise, the solution temperature (internal temperature) reached 100 ℃ and then the mixture was stirred for 2 hours (internal temperature 100 to 110 ℃) to obtain a polysiloxane solution. During the temperature rise and the heating and stirring, a mixed gas of 95 vol% of nitrogen and 5 vol% of oxygen was flowed at a rate of 0.05L/min. During the reaction, methanol was distilled off as a by-product, and 131.35g of hydration was measured. To the resulting polysiloxane solution, PGMEA was added so that the solid content concentration became 40 wt%, to obtain a polysiloxane solution. The weight average molecular weight of the obtained polysiloxane was 4,000. The molar ratios of repeating units derived from trifluoropropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride and 3- (3, 4-epoxycyclohexyl) propyltrimethoxysilane in the polysiloxane were 67.5 mol%, 17.5 mol%, 10 mol% and 5 mol%, respectively.

(preparation of resin composition for partition wall)

5.00g of a polysiloxane solution as a resin was mixed with 5.00g of a titanium dioxide pigment (R-960, manufactured by BASF Japan K.K.) as a white pigment, and the mixture was dispersed by using a mill-type disperser filled with zirconia beads to obtain a pigment dispersion. Next, in 4.76g of a solvent PGMEA, 9.98g of the pigment dispersion, 0.71g of diacetone alcohol, 1.57g of a polysiloxane solution, 0.050g of a photopolymerization initiator, that is, ethanone-1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] -1- (O-acetyloxime) (manufactured by BASF Japan K.K.), 0.400g of bis (2, 4, 6-trimethylbenzoyl) -phenylphosphine oxide (manufactured by BASF Japan K.K.), 0.100g of 1, 2-diisopropyl-3- [ bis (dimethylamino) methylene ] guanidine 2- (3-benzoylphenyl) propionate (manufactured by Fuji Kogyo Co., Ltd.) as a photobase generator, and 1.20g of dipentaerythritol hexaacrylate (manufactured by Nissan chemical Co., Ltd.) as a photopolymerizable compound were added, 1.00g of a 40 wt% PGMEA diluted solution of a photopolymerizable fluorine-containing compound ("Megafac" (registered trademark) RS-76-E, available from DIC corporation) as a liquid repellent compound, 0.100g of 3 ', 4' -epoxycyclohexylmethyl-3, 4-epoxycyclohexanecarboxylate (made by Cello Co., Ltd.), 0.030g of ethylene bis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate ] (made by BASF Japan Co., Ltd.), 0.100g (corresponding to a concentration of 500ppm) of a PGMEA10 wt% diluted solution of an acrylic surfactant ("BYK" (registered trademark) 352, made by Big Chemie Japan Co., Ltd.) were dissolved and stirred. Then, the mixture was filtered through a 5.0 μm filter to obtain a resin composition for partition walls.

(formation of light-shielding layer)

A resin composition for a light shielding layer was applied to a10 cm-square alkali-free glass substrate (thickness 0.7mm, manufactured by AGC Technoglass Co., Ltd.) by a spin coater so that the cured film thickness became 1.5 μm, and prebaked at 90 ℃ for 10 minutes. On the coating film, a mask aligner PEM-6M (manufactured by Union optical Co., Ltd.) was used at 100mJ/cm through a photomask having a shape corresponding to the light-shielding layer of examples 1 to 5 and comparative examples 1 to 3 described later ² Is exposed toThe light quantity is exposed to ultraviolet light. Subsequently, development was performed with an alkaline developer of a 0.5 mass% aqueous solution of tetramethylammonium hydroxide, followed by pure water washing, thereby obtaining a patterned substrate. The resulting patterned substrate was cured by holding it in a hot air oven at 230 ℃ for 30 minutes to form the following light-shielding layer: a light-shielding layer having a cell lattice (shown by a square broken line in the figure) having a repeating structure in the shape of a schematic view of the shape of the light-shielding layer described in examples or comparative examples (FIG. 2, 9 or 14) was patterned in a range of 7cm square.

(evaluation method of light-shielding layer shape and opening shape)

The partition-equipped substrate thus produced was photographed from the top surface direction by an optical microscope image using a laser microscope (color 3D laser microscope VK-9710, manufactured by KEYENCE), and the portions of the parameters in fig. 2, 9 and 14 were measured using accompanying software.

(production of base plate with partition wall)

The resin composition for barrier ribs was spin-coated on the substrate on which the light-shielding layer was formed, and dried at 90 ℃ for 2 minutes using a hot plate (SCW-636, manufactured by scr Semiconductor solvents) to prepare a dry film. A photomask corresponding to the partition wall shape of examples 1 to 5 and comparative examples 1 to 3 described later was aligned with the light-shielding layer using a collimator (PLA-501F, manufactured by Canon Co., Ltd.) and an ultra-high pressure mercury lamp as a light source, and then the photomask was aligned at 200mJ/cm ² The dry film thus produced was exposed to light with the exposure amount of (i line). Then, the resultant was subjected to spray development using an automatic developing apparatus (AD-2000, manufactured by Takizawa Sangyo Co., Ltd.) for 100 seconds using a 0.045 wt% potassium hydroxide aqueous solution, followed by rinsing with water for 30 seconds. Then, the substrate was heated in an oven (IHPS-222, manufactured by Espec corporation) at a temperature of 230 ℃ for 30 minutes in the air to prepare the following partition-equipped substrate: on a glass substrate, barrier ribs having a thickness of 22 μm and a cell lattice (shown by a square broken line in the figure) having a repeating structure in the shape of a barrier rib shape schematic diagram (fig. 3, 8, 10 to 13) described in examples or comparative examples are formed in a range of 7cm square on a light-shielding layer having the shape of a corresponding light-shielding layer shape schematic diagram (fig. 2, 9 or 14)A method for preparing a medical liquid.

(method of evaluating partition wall shape and opening shape)

The prepared substrate with partition walls was subjected to an optical microscope image by a laser microscope (color 3D laser microscope VK-9710, manufactured by KEYENCE) from the top surface direction in a camera mode, and the portions of the parameters in fig. 3, 8, 10 to 13 were measured by attached software.

(method of evaluating luminance)

Wavelength conversion substrates were prepared by applying and curing a wavelength conversion paste and a light scattering paste on the substrates with partition walls of examples 1 to 5 and comparative examples 1 and 2 by the following methods.

As the applicator head, an applicator head having 51 orifices with an orifice diameter of 50 μm and an orifice length of 130 μm arranged at a pitch of 300 μm in the longitudinal direction of the applicator head was used. As the coating device, a Multi-function laboratory Coater (Multi-lab Coater, manufactured by Toray Engineering Co., Ltd.) was used, the discharge port at the left end of the nozzle was aligned so as to be located at a stripe portion about 2.75cm away from the left end of the partition wall pattern, the direction parallel to the stripe was aligned with the nozzle traveling direction, then a pressure of 500 to 1,500kPa was applied to the coating head by air, the traveling speed with respect to the substrate was varied within a range of 20 to 200mm/s, and the nozzle was coated on the substrate with the partition wall while discharging the light scattering paste for blue sub-pixels, thereby filling the light scattering paste for blue sub-pixels. Then, the mixture was dried on a hot plate at 100 ℃ for 10 minutes and further subjected to an ultrahigh pressure mercury lamp at 200mJ/cm under a nitrogen atmosphere ² The exposure amount (i line) of (1) is cured by exposure. Next, the paste in the coating head was replaced with a wavelength conversion paste for green subpixels, and after aligning the paste with the partition substrate at the same position as described above, the paste was similarly coated by moving the position of the coating head by +100 μm in the direction orthogonal to the stripes of the partitions, and then dried and cured by exposure. The paste in the coating head is replaced by wavelength conversion paste for red sub-pixel, and the paste is aligned with the substrate with partition wall at the same position as that of the light scattering paste for blue sub-pixel, and then the paste is coated in the direction perpendicular to the stripe of the partition wallThe head position was moved by +200 μm, and the substrate was similarly coated, dried, and cured by exposure to light, thereby producing wavelength conversion substrates coated with blue, green, and red 3-color sub-pixels, respectively. In this case, the thickness of each wavelength conversion layer is set to 20 μm at the center of the cell lattice in the substrate of the partition wall having the shape of fig. 3, 8, 10 to 12; the pressure and the traveling speed at the time of coating were adjusted so that the thickness of the substrate of the partition wall in the shape of fig. 13 became 20 μm at the center of the opening of the partition wall in the direction perpendicular to the tape.

The wavelength conversion paste and the light scattering paste were applied to the partition wall-equipped substrate of comparative example 3 and cured by the following method to produce a wavelength conversion substrate.

As the coating device, a dispenser (ML-5000XII, manufactured by Musashi Engineering) in which a table (SHOT mini (registered trademark) 200SX-SS, manufactured by Musashi Engineering) and a nozzle (SHN-0.2N, manufactured by Musashi Engineering) as a discharge device were connected was used. Near the center of the pattern of the substrate with the partition wall, a portion where the light-shielding layer also has an opening in the opening of the partition wall is applied by dropping the light-scattering paste for blue subpixels via a nozzle. The blue light scattering paste was similarly applied to the coated portions at 4 total locations, i.e., a-300 μm location and a +300 μm location in the direction perpendicular to the stripes of the partition walls and a-300 μm location and a +300 μm location in the direction parallel to the stripes of the partition walls. Then dried on a hot plate at 100 ℃ for 10 minutes and further treated with an ultra-high pressure mercury lamp under nitrogen atmosphere at 200mJ/cm ² The exposure amount of (i line) is used for exposure to light and curing. Next, the paste of the dispenser was replaced with the wavelength conversion paste for green subpixels, and after the first applied portion was aligned with the substrate with partition walls, the paste was applied in the same manner at +100 μm in the direction orthogonal to the stripes of the partition walls, and at 4 portions in total of a portion of-300 μm and a portion of +300 μm in the direction orthogonal to the stripes of the partition walls and a portion of-300 μm and a portion of +300 μm in the direction parallel to the stripes of the partition walls from this portion, and was dried and exposed to light to cure. Will be distributed againThe paste of the device was replaced with a wavelength conversion paste for red subpixels, and after the first applied portion was aligned with the substrate with partition walls, the paste was similarly applied to 4 total portions of +200 μm in the direction orthogonal to the stripes of the partition walls, a portion of-300 μm and a portion of +300 μm in the direction orthogonal to the stripes of the partition walls from the portion, and a portion of-300 μm and a portion of +300 μm in the direction parallel to the stripes of the partition walls, followed by drying, exposure, and curing, thereby producing a wavelength conversion substrate coated with blue, green, and red 3-color subpixels in the range of 5 pixels, respectively. At this time, the ejection amount was adjusted so that the thickness of each wavelength conversion layer became 20 μm at the center of the cell.

The wavelength conversion substrates of examples 1 to 3 and comparative examples 1 to 3 produced by the above-described method were irradiated with blue light at the center of 1 cell in the vicinity of the center of the substrate, where the light scattering layer for blue sub-pixels was formed (in comparative example 3, the portion where the light scattering paste for blue sub-pixels was first applied). As the blue light source, a blue backlight for LCD obtained by decomposing a commercially available liquid crystal monitor (SW2700PT, manufactured by BenQ) was used. Further, in order to irradiate light only to the center of the cell lattice, a photomask having 1 circular opening with a diameter of 30 μm was disposed on the blue light source, and on the photomask, a wavelength conversion substrate was disposed so that the center of a portion of the light shielding layer having an opening also at the opening of the partition coincides with the center of the hole of the photomask and the surface on which the partition was formed was on the photomask side. While the blue light was irradiated, the two-dimensional spectral radiance was measured from the substrate surface side on which no partition wall was formed, using a two-dimensional spectral radiance meter (SR-5000M, manufactured by TOPCON TECHNOLOGOUSE Co., Ltd.). In this case, as the luminance evaluation criteria, when the luminance of blue light at the center of the cell lattice on the aperture of the photomask of example 1 is 100, a case where the relative value of the luminance is 95 or more is defined as a, a case where the relative value is 80 or more and less than 95 is defined as B, and a case where the relative value is less than 80 is defined as C.

(evaluation method of longitudinal light diffusion)

In the wavelength conversion substrate prepared for luminance evaluation, similarly to the luminance evaluation, light from a blue light source was irradiated through a photomask to the center of a portion where the light shielding layer also had an opening at the opening of the partition wall where the light scattering layer for blue sub-pixel was formed near the center of the substrate, and the two-dimensional spectral radiance was measured using SR-5000M. The light diffusion in the longitudinal direction, i.e. parallel to the strip, was evaluated. In this case, when the luminance of blue light at the center of the opening of the light-shielding layer in the hole of the photomask is 100, the luminance of the opening of the light-shielding layer on the lower side in the direction parallel to the stripe is measured, and for the evaluation criterion of vertical light diffusion, a case where light emission cannot be observed below the detection lower limit, a case where the relative value of luminance is less than 1, and a case where the relative value is 1 or more are defined as a. In the case of E, since light is emitted at a constant or higher luminance at the center of the sub-pixels adjacent in the direction parallel to the stripe, light diffusion is large and is not suitable.

(method of evaluating color mixture)

In the wavelength conversion substrate prepared for luminance evaluation, light from a blue light source was irradiated to the center of the cell lattice in which the wavelength conversion layer for green sub-pixels was formed through a photomask in the same manner as in luminance evaluation, and the two-dimensional spectral radiance was measured using SR-5000M. At this time, the relative value of the red luminance in the wavelength conversion layer for the adjacent red subpixel was measured with the green light luminance at the center of the cell lattice on the aperture of the photomask set to 100. The evaluation criteria for color mixture were a when the red luminance was not observed below the detection limit, C when the red luminance was less than 1, and D when the red luminance was 1 or more.

(evaluation method of Cross wall Top crossing)

With respect to the wavelength conversion substrate produced by the above method, the presence or absence of the wavelength conversion layer on the lateral barrier wall and the thickness thereof when present were observed with a laser microscope. A represents the case where the wavelength converting layer is not visible on the lateral walls, B represents the case where the wavelength converting layer is visible on the lateral walls but the thickness thereof is less than 1 μm, C represents the case where the thickness is 1 μm or more and less than 3 μm, D represents the case where the thickness is 3 μm or more and less than 10 μm, and E represents the case where the thickness is 10 μm or more. In the case of E, the wavelength conversion substrate is not suitable because a wide gap is formed when the wavelength conversion substrate is bonded to the OLED substrate or the LED substrate.

(evaluation results)

The evaluation results are shown in table 1. Examples 1 to 5 were all good. Comparative example 1, in which the aperture ratio of the light-shielding layer was large and only the light-shielding layer had 1 pattern having an aperture at the aperture of the partition wall, was low in luminance and unsuitable. In comparative example 2 in which the width of the horizontal partition wall was large, the top span of the horizontal partition wall was significant, and the flow direction and the flow degree were random, so that the film thickness unevenness at the center of the opening of the partition wall was also large, and other evaluations could not be performed.

In comparative example 3 in which the light-shielding layer did not have an opening in the opening of the partition wall, the vertical light diffusion was significant, and this was not suitable.

[ Table 1]

[ TABLE 1]

Description of the reference numerals

1 bulkhead

2 opening part

3 base plate

4 coating head

5 paste

6 pressure piping

7 discharge port

8 light-shielding layer

9 wavelength conversion layer

Industrial applicability

According to the present invention, a wavelength conversion substrate can be provided in which a wavelength conversion layer can be easily formed and light diffusion to adjacent sub-pixels can be suppressed, and the present invention can be effectively used for a wavelength conversion display.

Claims

1. A method for manufacturing a wavelength conversion substrate, comprising a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, wherein an opening of the partition wall is in a stripe shape, the light-shielding layer has a structure in which the opening and the light-shielding portion overlap in the stripe direction in 1 stripe of the stripe shape, and an aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%, and the method comprises a step of applying a nozzle coating to the wavelength conversion paste so that the opening of the light-shielding layer and the light-shielding portion of the light-shielding layer have the same composition in the 1 stripe.

2. A method of manufacturing a wavelength conversion substrate having a substrate, a light-shielding layer, partition walls, and a wavelength conversion layer, wherein openings of the partition walls are in a stripe shape, the openings of the partition walls have a structure in which at least 2 or more kinds of patterns are repeated in the stripe direction in 1 stripe of the stripe shape, the light-shielding layer also has openings in the openings of the partition walls in at least 1 of the repeated patterns, and the light-shielding layer does not substantially have openings in the openings of the partition walls in at least 1 of the repeated patterns, and the method of manufacturing the wavelength conversion substrate has a structure in which a portion where the light-shielding layer has an opening in the opening of the partition wall and a portion where the light-shielding layer does not have an opening in the opening of the partition wall have the same composition, and applying a wavelength conversion paste to the opening of the wavelength conversion substrate by a nozzle.

3. The method for manufacturing a wavelength conversion substrate according to claim 1 or 2, wherein an aperture ratio of the partition walls in the at least 1 stripe is 50 to 95%.

4. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 3, wherein a thickness H of the partition wall and a thickness T of the light shielding layer ₁ And a thickness T of the wavelength conversion layer ₂ Satisfies the following formulas (1) and (2),

H/100≤T ₁ ≤H/3 (1)

H/2≤T ₂ ≤H (2)。

5. the method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 4, wherein a planarization layer is further provided between the partition wall and the light shielding layer.

6. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 5, wherein the wavelength conversion layer contains a resin.

7. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 6, wherein a void ratio of the wavelength conversion layer is 0.01 to 10%.

8. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 7, wherein the light-shielding layer has a reflectance of 0.1 to 10%.

9. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 8, wherein the wavelength conversion layer contains an inorganic phosphor.

10. The method for manufacturing a wavelength conversion substrate according to any one of claims 1 to 8, wherein the wavelength conversion layer contains quantum dots.

11. A wavelength conversion substrate comprising a substrate, a light-shielding layer, a partition wall, and a wavelength conversion layer, wherein an opening of the partition wall is in a stripe shape, the light-shielding layer has a structure in which an opening and a light-shielding portion are repeated in the stripe direction in 1 stripe of the stripe shape, the aperture ratio of the light-shielding layer in the 1 stripe is 5 to 70%, and the wavelength conversion layer has the same composition in both the opening of the light-shielding layer and the light-shielding portion in the 1 stripe.

12. A wavelength conversion substrate comprising a substrate, a light-shielding layer, partition walls, and a wavelength conversion layer, wherein the openings of the partition walls are in a stripe shape, the openings of the partition walls have a structure in which at least 2 or more kinds of patterns are repeated in the stripe direction in 1 stripe of the stripe shape, the light-shielding layer also has openings in the openings of the partition walls in at least 1 of the repeated patterns, the light-shielding layer does not substantially have openings in the openings of the partition walls in at least 1 of the repeated patterns, and the wavelength conversion layer has the same composition in both of a portion where the light-shielding layer has an opening in the opening of the partition wall and a portion where the light-shielding layer does not have an opening in the opening of the partition wall.

13. A display having the wavelength converting substrate of claim 11 or 12, and an OLED or LED as a light source.