Wavelength conversion member and wavelength conversion member manufacturing method

Abstract

Provided are a wavelength conversion member with which it is possible to suppress a decrease in wavelength conversion efficiency, and a wavelength conversion member manufacturing method. The wavelength conversion member comprises a layered body which includes: a first barrier layer having a first main surface, a second main surface positioned opposite the first main surface, and an end surface connected to the first main surface; a wavelength conversion layer that has a third main surface and a fourth main surface positioned opposite the third main surface, and which is disposed on the first barrier layer with the third main surface and the second main surface of the first barrier layer facing each other, the wavelength conversion layer including quantum dots; and a second barrier layer that includes a fifth main surface and a sixth main surface positioned opposite the fifth main surface, and which is disposed on the wavelength conversion layer with the fifth main surface and the fourth main surface of the wavelength conversion layer facing each other. The wavelength conversion layer is positioned on the inside of the end surface in one cross section intersecting the third main surface and taken through the end surface, and has a first side surface connecting the third main surface and the fourth main surface. The first side surface is coated with a coating film.

Description

Wavelength conversion member and method for manufacturing wavelength conversion member

[0001] The present disclosure relates to a wavelength conversion member and a method for manufacturing a wavelength conversion member.

[0002] In the field of image display devices such as liquid crystal display devices, the use of wavelength conversion members containing quantum dots has been proposed to improve color reproducibility. In such devices, the wavelength conversion efficiency of the wavelength conversion member may decrease when the quantum dots are exposed to moisture, oxygen, etc. Therefore, for example, International Publication No. 2016 / 039079 proposes a functional laminate film having a functional layer laminate including a quantum dot-containing functional layer and two gas barrier films, and an end surface protection layer covering the end surfaces of the functional layer laminate.

[0003] However, there is still room for improvement in terms of suppressing the decrease in the wavelength conversion efficiency of the wavelength conversion member.

[0004] Therefore, an object of the present disclosure is to provide a wavelength conversion member that can suppress a decrease in wavelength conversion efficiency and a method for manufacturing a wavelength conversion member.

[0005] A wavelength conversion member according to an embodiment of the present disclosure comprises a laminate including: a first barrier layer including a first main surface, a second main surface opposite the first main surface, and an end surface connected to the first main surface; a wavelength conversion layer including quantum dots, including a third main surface and a fourth main surface opposite the third main surface, and disposed on the first barrier layer with the third main surface facing the second main surface of the first barrier layer; and a second barrier layer including a fifth main surface and a sixth main surface opposite the fifth main surface, and disposed on the wavelength conversion layer with the fifth main surface facing the fourth main surface of the wavelength conversion layer, wherein the wavelength conversion layer has a first side surface that is located inside the end surface and connects the third main surface and the fourth main surface in a cross section that intersects the third main surface and passes through the end surface, and the first side surface is covered with a coating film.

[0006] a wavelength conversion member manufacturing method according to an embodiment of the present disclosure includes: preparing a laminate sheet including: a first barrier sheet including a first main surface and a second main surface opposite to the first main surface; a wavelength conversion sheet including quantum dots, including a third main surface and a fourth main surface opposite to the third main surface, and disposed on the first barrier sheet with the third main surface facing the second main surface of the first barrier sheet; and a second barrier sheet including a fifth main surface and a sixth main surface opposite to the fifth main surface, and disposed on the wavelength conversion sheet with the fifth main surface facing the fourth main surface of the wavelength conversion sheet; forming a hole extending through the second barrier sheet, the wavelength conversion sheet, and a part of the first barrier sheet, the hole having an inner surface including a third side surface connecting the fifth main surface and the sixth main surface, a first side surface connecting the third main surface and the fourth main surface, and a second side surface connecting to the second main surface; The method includes covering the inner surface of the hole with a coating film, cutting the laminate sheet from the sixth main surface toward the first main surface to expose an end surface connected to the first main surface, and forming a spare wavelength conversion member including the hole, wherein the spare wavelength conversion member is such that the hole is located inside the end surface in a cross section that intersects the third main surface and passes through the end surface.

[0007] Furthermore, a method for manufacturing a wavelength conversion member according to another embodiment of the present disclosure includes preparing a laminate sheet including: a first barrier sheet including a first main surface and a second main surface located opposite to the first main surface; a wavelength conversion sheet including quantum dots, including a third main surface and a fourth main surface located opposite to the third main surface, and disposed on the first barrier sheet with the third main surface facing the second main surface of the first barrier sheet; and a second barrier sheet including a fifth main surface and a sixth main surface located opposite to the fifth main surface, and disposed on the wavelength conversion sheet with the fifth main surface facing the fourth main surface of the wavelength conversion sheet; the hole having an inner surface including a third side surface connecting the fifth main surface and the sixth main surface, a first side surface connecting the third main surface and the fourth main surface, a second side surface connecting to the second main surface, and a bottom surface made of the first barrier sheet; coating the inner surface with a coating film; cutting the laminate sheet from the bottom surface toward the first main surface to expose an end surface connecting to the first main surface, and forming a spare wavelength conversion member including the third side surface, the first side surface, and the second side surface, wherein the spare wavelength conversion member is such that the third side surface, the first side surface, and the second side surface are located more inward than the end surface in a cross section that intersects the third main surface and passes through the end surface.

[0008] According to a wavelength conversion member and a method for manufacturing a wavelength conversion member according to an embodiment of the present disclosure, it is possible to provide a wavelength conversion member and a method for manufacturing a wavelength conversion member that can suppress a decrease in wavelength conversion efficiency.

[0009] FIG. 1B is a schematic top view of a wavelength conversion member according to embodiment 1 of the present disclosure. FIG. 1C is a schematic cross-sectional view showing a portion of the cross section of line 1B-1B of the wavelength conversion member shown in FIG. 1A. FIG. 1D is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1E is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1F is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1G is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1H is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1I is a schematic cross-sectional view showing a portion of another aspect of a wavelength conversion member according to embodiment 1. FIG. 1 is a schematic cross-sectional view showing another step of the method for manufacturing a wavelength conversion member according to embodiment 1 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing another step of the method for manufacturing a wavelength conversion member according to embodiment 1 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing another step of the method for manufacturing a wavelength conversion member according to embodiment 1 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing another step of the method for manufacturing a wavelength conversion member according to embodiment 2 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing one ...3 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing one step of the method for manufacturing a wavelength conversion member according to embodiment 3 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing one step of the method for manufacturing a wavelength conversion member according to embodiment 4 of the present disclosure. FIG. 1 is a schematic cross-sectional view showing one step of the method for manufacturing a wavelength conversion member according to embodiment 4 of the present disclosure.

[0010] Hereinafter, embodiments for carrying out the invention according to the present disclosure will be described with reference to the drawings. Note that the wavelength conversion member and manufacturing method for a wavelength conversion member according to the present disclosure described below are intended to embody the technical concept of the invention according to the present disclosure, and unless otherwise specified, the invention according to the present disclosure is not limited to the following. In each drawing, components having the same function may be designated by the same reference numeral. For convenience, the embodiments may be shown separately in consideration of ease of explanation or understanding of the main points, but partial substitution or combination of configurations shown in different embodiments is possible. In the embodiments described below, descriptions of matters common to the above will be omitted, and only differences will be described. In particular, similar effects due to similar configurations will not be mentioned sequentially in each embodiment. The size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity of explanation. In addition, end views showing only the cut surface may be shown as cross-sectional views.

[0011] As used herein, the term "process" refers not only to an independent process, but also to processes that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. Furthermore, when multiple substances corresponding to each component are present in the composition, the content of each component in the composition refers to the total amount of those multiple substances present in the composition, unless otherwise specified. Furthermore, the upper and lower limits of the numerical ranges described herein can be arbitrarily selected and combined from the numerical values ​​exemplified as numerical ranges. In this specification, the relationship between color names and chromaticity coordinates, the relationship between light wavelength ranges and monochromatic light color names, etc., conforms to JIS Z8110. The half-width of a phosphor refers to the wavelength width (full width at half maximum; FWHM) of the emission spectrum of a light-emitting material, where the emission intensity is 50% of the maximum emission intensity. As used herein, the term "layer" includes cases where the layer is formed over the entire region, as well as cases where the layer is formed only in a portion of the region, when the region where the layer is present is observed. Furthermore, the term "laminated" refers to stacking layers, and two or more layers may be bonded or separable. Furthermore, the term "laminated" refers to two or more layers that are in contact with each other, or two or more layers that are not in contact with each other but are arranged via other members. Hereinafter, embodiments of the present disclosure will be described in detail. However, the embodiments described below are intended to exemplify wavelength conversion members and methods for manufacturing the same in order to embody the technical ideas of the present disclosure, and the present disclosure is not limited to the wavelength conversion members and methods for manufacturing the same described below.

[0012] 1. Embodiment 1 As shown in FIG. 1A , a wavelength conversion member 100 according to embodiment 1 has, for example, a substantially rectangular shape in top view. The wavelength conversion member 100 has, for example, a thin plate shape. As shown in FIG. 1B , the wavelength conversion member 100 includes a laminate 1 including a first barrier layer 10, a wavelength conversion layer 20, and a second barrier layer 30. The wavelength conversion layer 20 is disposed on the first barrier layer 10. The second barrier layer 30 is disposed on the wavelength conversion layer 20. In this specification, the phrase "above" another layer does not necessarily mean that the layers are disposed in contact with each other, but also includes the case where the layers are disposed with another member interposed between them.

[0013] The first barrier layer 10 includes a first major surface 11 and an end surface (hereinafter also referred to as a first end surface 13) connected to the first major surface 11. The wavelength conversion layer 20 includes quantum dots. The wavelength conversion layer 20 includes a third major surface 21 and a fourth major surface 22 located opposite the third major surface 21. At a cross section M1 that intersects the third major surface 21 and passes through the first end surface 13, the wavelength conversion layer 20 has a first side surface 24 that is located inside the first end surface 13 and connects the third major surface 21 and the fourth major surface 22. The first side surface 24 is covered by a coating film 3. Hereinafter, the cross section M1 that intersects the third major surface 21 and passes through the first end surface 13 will also be simply referred to as the "cross section M1." Furthermore, throughout this specification, cross section M1 is not limited to one and the same cross section, but may be any cross section that intersects with the third main surface 21 and passes through the first end surface 13 and the first side surface 24.

[0014] As shown in Fig. 1B , in embodiment 1, the first barrier layer 10, the wavelength conversion layer 20, and the second barrier layer 30 are stacked in this order in the thickness direction Z. In the laminate 1 of embodiment 1, holes 2 are provided throughout the second barrier layer 30, the wavelength conversion layer 20, and parts of the first barrier layer 10. The holes 2 are defined by inner surfaces 2a. The inner surfaces 2a include, for example, an inner side surface 2c, an outer side surface 2d, and a bottom surface 2b. The inner side surface 2c includes a third side surface 34 of the second barrier layer 30, a first side surface 24 of the wavelength conversion layer 20, and a second side surface 14 of the first barrier layer 10, which will be described later. As shown in Fig. 1A , the holes 2 are provided along the outer periphery of the laminate 1 in a top view.

[0015] In this specification, in the wavelength conversion member 100 and the laminate 1, the side of the first barrier layer 10 may be referred to as the "lower side", the "lower surface side", etc., and the side opposite the first barrier layer 10 in the thickness direction Z may be referred to as the "upper side", the "upper surface side", etc. Furthermore, a direction intersecting the thickness direction Z may be referred to as the "lateral side".

[0016] The wavelength conversion member 100 is used, for example, in a backlight unit of a liquid crystal display device. In this case, the wavelength conversion member 100 is disposed, for example, on a plurality of light-emitting elements, collectively covering the plurality of light-emitting elements. Light emitted from the plurality of light-emitting elements is incident on the wavelength conversion member 100 from the bottom surface (e.g., the first barrier layer 10 side) of the wavelength conversion member 100. A portion of the incident light is wavelength-converted and is emitted from the top surface (e.g., the second barrier layer 30 side) of the wavelength conversion member 100 together with incident light that is not wavelength-converted.

[0017] The configuration of the wavelength conversion member 100 will be described in detail below.

[0018] (First Barrier Layer) The first barrier layer 10 is a layer having a barrier function against, for example, moisture, oxygen, etc. The first barrier layer 10 is, for example, a barrier film having an inorganic layer. The first barrier layer 10 has, for example, a substrate film which is a film-like cured resin product and an inorganic layer provided on at least one main surface of the substrate film. The barrier function of the first barrier layer 10 can prevent moisture, oxygen, etc. that enter from the first barrier layer 10 side from reaching the wavelength conversion layer 20, and can suppress a decrease in the luminous efficiency of the quantum dots contained in the wavelength conversion layer 20.

[0019] 1B , the first barrier layer 10 includes a first major surface 11 and a second major surface 12 located opposite the first major surface 11. The first major surface 11 and the second major surface 12 are located opposite each other in the thickness direction Z. The first major surface 11 and the second major surface 12 are, for example, substantially flat surfaces perpendicular to the thickness direction Z. In this specification, the surface of a layer being substantially flat means that the surface of the layer is a flat surface that includes irregularities that occur during the manufacturing process, such as lamination. The irregularities include, for example, a height difference of 20 μm or less, or 2 μm or less.

[0020] The average thickness of the first barrier layer 10 may be, for example, 5% to 60% of the average thickness of the laminate 1, and preferably 20% to 45%. The average thickness of the first barrier layer 10 may be, for example, 20 μm to 150 μm, and preferably 20 μm to 120 μm, or 25 μm to 100 μm. The average thickness of the first barrier layer 10 can also be said to be the average distance between the first main surface 11 and the second main surface 12. When the first barrier layer 10 is in the form of a film, the average thickness can be determined, for example, as the arithmetic mean value of thicknesses measured at any three locations using a reflectance spectroscopic film thickness meter or the like.

[0021] The first barrier layer 10 includes a first end face 13 and a second side face 14. The first end face 13 is connected to the first main surface 11. In embodiment 1, the first end face 13 connects the first main surface 11 and the second main surface 12. The first end face 13 is, for example, a plane extending in the thickness direction Z. The second side face 14 is connected to the second main surface 12. The second side face 14 is located more inward than the first end face 13 in the cross section M1. The second side face 14 may be a plane extending in the thickness direction Z.

[0022] The second side surface 14 is arranged along the outer periphery of the laminate 1. The second side surface 14 is arranged, for example, in a ring shape along the outer periphery of the laminate 1. In the cross section M1, the distance between the second side surface 14 and the first end face 13 may be, for example, 100 μm or more and 1000 μm or less, preferably 100 μm or more and 500 μm or less. When the second side surface 14 is inclined with respect to the first end face 13, the distance between the second side surface 14 and the first end face 13 may be, for example, the distance between the upper end of the second side surface 14 and the plane including the first end face 13. When the distance between the first side surface 24 and the first end face 13 is 100 μm or more, damage to the coating film 3 due to an external force, as described below, can be suppressed. Furthermore, when the distance between the first side surface 24 and the first end face 13 is 1000 μm or less, for example, the area of ​​the portion not performing the wavelength conversion function can be reduced. This makes it easier to narrow the bezel width of a liquid crystal display device, for example.

[0023] In embodiment 1, the second side surface 14 is included in the inner surface 2a that defines the hole 2. As shown in FIG. 1B , the inner surface 2a includes, for example, an inner side surface 2c, an outer side surface 2d, and a bottom surface 2b. The inner side surface 2c and the outer side surface 2d face each other. Here, in this specification, "face to face" includes both a state in which the surfaces face each other without any other component interposed therebetween and a state in which the surfaces face each other with any other component interposed therebetween. At the cross section M1, the distance between the inner side surface 2c and the outer side surface 2d may be, for example, 25 μm or more and 1000 μm or less, and preferably 50 μm or more and 400 μm or less. The inner side surface 2c and the outer side surface 2d are connected at the bottom surface 2b. The bottom surface 2b is made of a first barrier layer 10. The inner surface 2a is covered with a coating film 3, which will be described later.

[0024] The second side surface 14 is included in a side surface 2c inside the inner surface 2a. The second side surface 14 is connected to the bottom surface 2b, for example.

[0025] The second side surface 14 is covered with a coating film 3. The coating film 3 is, for example, a film that suppresses moisture from entering the inside of the wavelength conversion layer 20 from the second side surface 14. The coating film 3 may further be a film that suppresses oxygen from entering the inside of the laminate 1. The coating film 3 may be composed of multiple layers. The average thickness of the coating film 3 may be, for example, 0.05 μm or more and 50 μm or less, and preferably 0.2 μm or more and 10 μm or less. The coating film 3 may further cover the bottom surface 2b.

[0026] 1C , the first barrier layer 10 may include a primary barrier layer 15 and an intermediate layer 16. The intermediate layer 16 is disposed between the primary barrier layer 15 and the wavelength conversion layer 20. The primary barrier layer 15 includes, for example, a first primary surface 11. The intermediate layer 16 includes, for example, a second primary surface 12. The intermediate layer 16 may also be referred to as, for example, a secondary barrier layer.

[0027] The main barrier layer 15, for example, substantially fulfills the barrier function of the first barrier layer 10. The intermediate layer 16 may be made of a material that has good adhesion to both the wavelength conversion layer 20 and the main barrier layer 15. This makes it possible to prevent moisture and the like from entering through the boundary between the intermediate layer 16 and the wavelength conversion layer 20, the boundary between the intermediate layer 16 and the main barrier layer 15, and the like.

[0028] The average thickness of the intermediate layer 16 may be, for example, 1% to 50%, and preferably 10% to 30%, of the average thickness of the first barrier layer 10. The average thickness of the intermediate layer 16 may be, for example, 1 μm to 50 μm, and preferably 1 μm or more or 10 μm or more, and preferably 5 μm or less or 3 μm or less.

[0029] 1C , when the first barrier layer 10 includes a main barrier layer 15 and an intermediate layer 16, the second side surface 14 and the bottom surface 2b of the hole 2 may be included in the intermediate layer 16. That is, a part of the first barrier layer 10 where the hole 2 is provided may be the intermediate layer 16. This makes it possible to maintain a uniform thickness of the main barrier layer 15 in the first barrier layer 10, and to prevent a decrease in the barrier effect. Furthermore, it is preferable that the coating film 3 cover the boundary between the wavelength conversion layer 20 and the intermediate layer 16. This makes it possible to prevent moisture and the like from entering through the boundary between the wavelength conversion layer 20 and the intermediate layer 16.

[0030] 1G , when the first barrier layer 10 includes a main barrier layer 15 and an intermediate layer 16, the second side surface 14 and the bottom surface 2b of the hole 2 may be included in the main barrier layer 15. That is, a part of the first barrier layer 10 in which the hole 2 is provided may be the main barrier layer 15. The coating film 3 preferably covers the boundary between the main barrier layer 15 and the intermediate layer 16. This makes it possible to prevent moisture and the like from entering through the boundary between the main barrier layer 15 and the intermediate layer 16.

[0031] (Wavelength conversion layer) The wavelength conversion layer 20 converts the wavelength of part of the light incident on the wavelength conversion member 100. The wavelength conversion layer 20 contains quantum dots. The wavelength conversion layer 20 is, for example, a film-like cured resin containing quantum dots. The quantum dots will be described in detail later.

[0032] 1B , the wavelength conversion layer 20 includes a third major surface 21 and a fourth major surface 22 located opposite the third major surface 21. The third major surface 21 and the fourth major surface 22 are located opposite each other in the thickness direction Z. The third major surface 21 and the fourth major surface 22 are, for example, approximately flat surfaces perpendicular to the thickness direction Z. The wavelength conversion layer 20 is disposed on the first barrier layer 10 with the third major surface 21 facing the second major surface 12 of the first barrier layer 10.

[0033] The average thickness of the wavelength conversion layer 20 may be, for example, 20% to 1500% of the average thickness of the first barrier layer 10, and preferably 100% to 400%. The average thickness of the wavelength conversion layer 20 may be, for example, 30 μm to 200 μm, and preferably 30 μm to 150 μm, or 80 μm to 120 μm. The average thickness of the wavelength conversion layer 20 can also be said to be the average distance between the third main surface 21 and the fourth main surface 22. When the wavelength conversion layer 20 is in the form of a film, the average thickness can be determined in the same manner as for the film-shaped first barrier layer 10.

[0034] The wavelength conversion layer 20 includes an end face (hereinafter also referred to as a second end face 23) and a first side face 24. The second end face 23 may be located on the same plane as the first end face 13 of the first barrier layer 10. The second end face 23 connects the third major surface 21 and the fourth major surface 22. The second end face 23 may be a plane extending in the thickness direction Z. The first side face 24 connects the third major surface 21 and the fourth major surface 22. The first side face 24 is located inside the first end face 13 of the first barrier layer 10 in the cross section M1. "Located inside the first end face 13" means that the first side face 24 is located closer to the interior of the laminate 1 than the first end face 13 in the direction perpendicular to the thickness direction Z, with the first end face 13 as the reference. The first side face 24 may be a plane extending in the thickness direction Z.

[0035] The first side surface 24 is arranged along the outer periphery of the laminate 1. The first side surface 24 is arranged, for example, in a ring shape along the outer periphery of the laminate 1. The distance from the first side surface 24 to the first end surface 13 in the cross section M1 may be, for example, 100 μm or more and 1000 μm or less, preferably 100 μm or more and 500 μm or less. In the cross section M1, the distance from the first side surface 24 to the first end surface 13 may be equal to the distance from the second side surface 14 to the first end surface 13. Note that this distance is the distance between a plane including the first side surface 24 and a plane including the first end surface 13. Furthermore, this distance can also be referred to as the distance between the first side surface 24 and the first end surface 13 in a direction perpendicular to the thickness direction Z. When the first side surface 24 is inclined with respect to the first end surface 13, the distance between the first side surface 24 and the first end surface 13 may be, for example, the distance between the upper end of the first side surface 24 and the plane including the first end surface 13.

[0036] In the first embodiment, the first side surface 24 is included in the inner surface 2 a of the hole 2. The first side surface 24 is included in a side surface 2 c inside the inner surface 2 a. In the first embodiment, the first side surface 24 and the second side surface 14 are located on the same plane on the inner side surface 2 c.

[0037] The first side surface 24 is covered by a coating film 3. The coating film 3 continuously covers the first side surface 24 and the second side surface 14. The average thickness of the coating film 3 covering the first side surface 24 may be, for example, 0.2 μm or more and 10 μm or less. The average thickness of the coating film 3 covering the first side surface 24 may be equal to or different from the average thickness of the coating film 3 covering the second side surface 14.

[0038] The wavelength conversion layer 20 may be a single layer or may be two or more layers. When the wavelength conversion layer 20 is a multiple layer, the quantum dots contained in each layer may have different emission peak wavelengths. The wavelength conversion layer 20 may have at least one layer containing quantum dots, and may also have a layer containing, for example, a phosphor other than quantum dots. Each layer of the wavelength conversion layer 20 may contain one type of quantum dot, two or more types of quantum dots, or one or more types of quantum dots and one or more types of phosphors.

[0039] (Second Barrier Layer) The second barrier layer 30, like the first barrier layer 10, is a layer having a barrier function against, for example, moisture, oxygen, etc. The second barrier layer 30 can be, for example, a barrier film having an inorganic layer. The barrier function of the second barrier layer 30 can prevent moisture, oxygen, etc. that penetrate from the second barrier layer 30 side from reaching the wavelength conversion layer 20, thereby suppressing a decrease in the luminous efficiency of the quantum dots contained in the wavelength conversion layer 20. The second barrier layer 30 may be formed using, for example, the same materials as the base film and inorganic layer that constitute the first barrier layer 10.

[0040] 1B , the second barrier layer 30 includes a fifth major surface 31 and a sixth major surface 32 located opposite the fifth major surface 31. The fifth major surface 31 and the sixth major surface 32 are located opposite each other in the thickness direction Z. The fifth major surface 31 and the sixth major surface 32 are, for example, approximately flat surfaces perpendicular to the thickness direction Z. The second barrier layer 30 is disposed on the wavelength conversion layer 20 with the fifth major surface 31 facing the fourth major surface 22 of the wavelength conversion layer 20.

[0041] The average thickness of the second barrier layer 30 may be, for example, 10% to 750% of the average thickness of the first barrier layer 10, and preferably 50% to 200%. The average thickness of the second barrier layer 30 may be, for example, 20 μm to 150 μm, and preferably 20 μm to 120 μm, or 25 μm to 100 μm. The average thickness of the second barrier layer 30 can also be said to be the average distance between the fifth main surface 31 and the sixth main surface 32. When the second barrier layer 30 is in a film form, the average thickness can be determined in the same manner as for the film-like first barrier layer 10.

[0042] The second barrier layer 30 includes an end surface (hereinafter also referred to as a third end surface 33) and a third side surface 34. The third end surface 33 may be located on the same plane as the first end surface 13 of the first barrier layer 10. That is, the first end surface 13, the second end surface 23, and the third end surface 33 may be arranged on the same plane. The third end surface 33 connects the fifth main surface 31 and the sixth main surface 32. The third end surface 33 may be a plane extending in the thickness direction Z. The third side surface 34 connects the fifth main surface 31 and the sixth main surface 32. The third side surface 34 is located inside the first end surface 13 of the first barrier layer 10 at the cross section M1. The third side surface 34 may be a plane extending in the thickness direction Z.

[0043] The third side surface 34 is arranged along the outer periphery of the laminate 1. The third side surface 34 is arranged, for example, in a ring shape along the outer periphery of the laminate 1. The distance from the third side surface 34 to the first end surface 13 at the cross section M1 may be, for example, 100 μm or more and 1000 μm or less, preferably 100 μm or more and 500 μm or less. At the cross section M1, the distance from the third side surface 34 to the first end surface 13 may be equal to the distance from the second side surface 14 to the first end surface 13. Note that this distance is the distance between a plane including the third side surface 34 and a plane including the first end surface 13. This distance can also be referred to as the distance between the third side surface 34 and the first end surface 13 in a direction perpendicular to the thickness direction Z. When the third side surface 34 is inclined, the distance between the third side surface 34 and the first end surface 13 may be, for example, the distance between the upper end of the third side surface 34 and the plane including the first end surface 13.

[0044] In the first embodiment, the third side surface 34 is included in the inner surface 2a of the hole 2. The third side surface 34 is included in the inner side surface 2c of the inner surface 2a. In the first embodiment, the third side surface 34 and the first side surface 24 are located on the same plane on the inner side surface 2c. That is, the first side surface 24, the second side surface 14, and the third side surface 34 are located on the same plane on the inner side surface 2c.

[0045] The third side surface 34 is covered by the coating film 3 that covers the first side surface 24 and the second side surface 14. The coating film 3 continuously covers the first side surface 24, the second side surface 14, and the third side surface 34. The average thickness of the coating film 3 that covers the third side surface 34 may be, for example, 0.2 μm or more and 10 μm or less. The average thickness of the coating film 3 that covers the third side surface 34 may be equal to or different from the average thickness of the coating film 3 that covers the first side surface 24 and the second side surface 14.

[0046] Similarly to the first barrier layer 10, the second barrier layer 30 may include a main barrier layer and an intermediate layer disposed between the main barrier layer and the wavelength conversion layer.

[0047] (Hole) As described above, the hole 2 is defined by the inner surface 2a. The hole 2 is defined, for example, by an inner side surface 2c, an outer side surface 2d, and a bottom surface 2b. In this embodiment, the hole 2 is defined by the inner side surface 2c formed by the first barrier layer 10, the wavelength conversion layer 20, and the second barrier layer 30, the outer side surface 2d formed by the first barrier layer 10, the wavelength conversion layer 20, and the second barrier layer 30, and the bottom surface 2b formed by the first barrier layer 10. In embodiment 1, the hole 2 can also be considered a recess having an opening in the sixth main surface 32.

[0048] In the above, it has been described that the third side surface 34, the first side surface 24, the second side surface 14, and the bottom surface 2b of the inner surface 2a are covered with the coating film 3. However, as shown in FIG. 1B , the outer side surface 2d may also be covered with the coating film 3. That is, the entire inner surface 2a may be covered with the coating film 3. In embodiment 1, the holes 2 are not exposed on the outer peripheral surface of the laminate 1 and are separated from the outer peripheral surface of the laminate 1. The outer peripheral surface of the laminate 1 refers to the entire surface of the laminate 1 when viewed from the side. In this case, the outer peripheral surface of the laminate 1 can also be said to be the entire surface of the laminate 1 when viewed from a direction perpendicular to the thickness direction Z.

[0049] The hole 2 preferably has an uneven shape on the inner surface 2a. By having an uneven shape on the inner surface of the hole 2, the surface area of ​​the inner surface 2a increases, and the bonding strength between the coating film 3 and the inner surface 2a of the hole 2 is improved. Such an uneven shape can be formed by, for example, wet blasting or sand blasting.

[0050] As shown in FIG. 1D , a buffer material 4 may be further disposed in the hole 2. The buffer material 4 is disposed, for example, by filling the hole 2 whose inner surface 2a is covered with the coating film 3. The buffer material 4 is, for example, a resin having gas barrier properties and / or flexibility. The buffer material 4 may also contain a filler such as alumina or silica and have optical reflectivity. This allows a portion of the incident light entering the wavelength conversion member or a portion of the light emitted by quantum dots or the like contained in the wavelength conversion layer 20 to reach the inner surface 2a of the hole 2, to be reflected by the optically reflective buffer material 4. As a result, the amount of light emitted from the upper surface of the wavelength conversion member 100 can be increased. In other words, the luminous efficiency of the wavelength conversion member 100 can be improved. The buffer material 4 may contain, for example, a phenylsilicone-based resin.

[0051] 1A, the holes 2 are formed continuously in a ring shape along the outer periphery of the laminate 1 in a top view. However, as shown in FIG. 1E, the holes may be formed intermittently along the outer periphery of the laminate 101. That is, the laminate 101 may include a plurality of holes 102 spaced apart from one another. Note that adjacent holes 102 may be spaced apart from one another as shown in FIG. 1E, or may be arranged so that the ends of the holes 102 are partially connected. Furthermore, it is preferable that the distance between two adjacent holes 102 is small. This can prevent moisture and the like from passing between the holes 102 and entering the interior of the laminate 101. In this case, two adjacent holes 102 may be spaced apart by, for example, 1 μm or more and 500 μm or less, preferably 50 μm or more and 300 μm or less. As will be described later, when the laminate 101 includes a plurality of holes 102 spaced apart from one another, it is preferable to further arrange holes 102 inside or outside the spaced apart regions between the holes 102 when viewed from above. This makes it possible to effectively prevent moisture and the like from passing between the holes 102 and entering the interior of the laminate 101.

[0052] 1A or 1B, the hole 2 has a constant width. In this specification, the width of the hole 2 refers to the distance between the inner side surface 2c and the outer side surface 2d. That is, in the above-described example, the distance between the inner side surface 2c and the outer side surface 2d is constant when viewed from above and in a cross-sectional view. However, the width of the hole may be different when viewed from above and / or in a cross-sectional view.

[0053] For example, in a cross-sectional view, the width of the hole 2 may become narrower from the upper surface side to the lower surface side of the laminate 1. In other words, in a cross-sectional view, the distance between the inner side surface 2c and the outer side surface 2d may become smaller toward the first barrier layer 10. For example, the inner side surface 2c and the outer side surface 2d of the hole 2 may be flat, and the width of the hole 2 may become continuously smaller toward the first barrier layer 10. Alternatively, the width of the hole 2 may become discontinuously smaller toward the first barrier layer 10. In other words, the hole 2 may have a step on the inner side surface 2c and / or the outer side surface 2d.

[0054] Furthermore, as shown in FIG. 1F , for example, in a top view, the hole 112 may include a narrow portion 112A and a wide portion 112B. The narrow portion 112A and the wide portion 112B may be continuous. The hole 112 may include multiple narrow portions 112A and multiple wide portions 112B. In this case, the narrow portions 112A and the wide portions 112B may be alternately arranged at regular intervals. The length L2 of the wide portion 112B extending along the outer periphery of the laminate 111 (hereinafter also referred to as the length of the wide portion 112B) may be longer than the length L1 of the narrow portion 112A extending along the outer periphery of the laminate 111 (hereinafter also referred to as the length of the narrow portion 112A). The length L1 of the narrow portion 112A may be, for example, 3 μm or more and 200 μm or less. The length L2 of the wide portion 112B may be, for example, 0.5 mm or more and 200 mm or less, and may be 100 times or more the length L1 of the narrow portion 112A.

[0055] The holes 112 shown in FIG. 1F are formed, for example, as follows. First, similarly to FIG. 1E, a plurality of holes 102A are formed spaced apart from one another along the outer periphery of the laminate 111. In FIG. 1F, the holes 102A are indicated by dotted lines in the enlarged view at the bottom of the drawing. To facilitate understanding of the drawing, the dotted lines representing the holes 102A are drawn so as not to overlap with the solid lines representing the outlines of the holes 102. The plurality of holes 102A are formed intermittently in a top view. In this case, the plurality of holes 102A can also be referred to as holes in the first step. In this specification, a "step" in laser processing refers to each scan in which the position irradiated by scanning with laser light is different from the position irradiated by the preceding scan. On the other hand, each scan in which the position irradiated by scanning with laser light is the same as the position irradiated by the preceding scan is referred to as a "pass." Next, a plurality of holes 102B are formed spaced apart from one another inside or outside the plurality of holes 102A in a top view. In FIG. 1F , the holes 102B are indicated by dashed lines in the enlarged view at the bottom of the drawing. To facilitate understanding of the drawing, the dotted lines representing the holes 102B are drawn so as not to overlap with the solid lines representing the outlines of the holes 102. In FIG. 1F , the holes 102B are arranged outside the holes 102A. The holes 102B are formed along the outer periphery of the laminate 111. The holes 102B are formed intermittently in a top view. In this case, the holes 102B can also be considered second-step holes. Furthermore, the holes 102B are formed, for example, parallel to the holes 102A. It is preferable that the holes 102B straddle two adjacent holes 102A in a top view. This effectively prevents moisture and other contaminants from passing between the holes 102A and penetrating the interior of the laminate 111. 1F, the plurality of holes 102A and the plurality of holes 102B are in contact with each other to form one hole 112. However, this is not limited thereto, and the plurality of holes 102A and the plurality of holes 102B may be spaced apart. Furthermore, the hole 112 may include holes in the third step or later.

[0056] (Laminate) As shown in FIG. 1B , the laminate 1 includes a laminate located inside the first side surface 24 (hereinafter also referred to as the inner laminate 1A) and a laminate located outside the first side surface 24 (hereinafter also referred to as the outer laminate 1B). In FIG. 1B , the boundary between the inner laminate 1A and the outer laminate 1B is indicated by a dotted line to facilitate understanding of the drawing. The inner laminate 1A is the portion of the wavelength conversion member 100 that essentially performs the wavelength conversion function. As described above, the first side surface 24 may be located, for example, at a distance from the first end surface 13 in the range of 100 μm to 1000 μm, preferably in the range of 100 μm to 500 μm. This allows the range of the inner laminate 1A to be widened.

[0057] In the laminate 1, the second side surface 14, the first side surface 24, and the third side surface 34 may extend in a direction intersecting the thickness direction Z. The laminate 1 may further include additional layers as necessary. Examples of the additional layers include a hard coat layer, an optical compensation layer, and an adhesion-imparting layer.

[0058] In the wavelength conversion member having the above configuration, the coating film 3 is located inside the first end face 13, the second end face 23, and the third end face 33. This allows external forces applied from the side of the laminate 1 to be first received by the first end face 13, the second end face 23, and the third end face 33, thereby preventing damage to the coating film 3 due to the external forces. In particular, damage to the coating film 3 covering the first side face 24 can be prevented. As a result, exposure of the quantum dots to moisture and the like is prevented, and a decrease in the wavelength conversion efficiency of the wavelength conversion member can be prevented. Note that the external force applied from the side of the laminate 1 refers to, for example, a force applied by contacting the wavelength conversion member 100 with a frame, positioning member, or the like of a liquid crystal display device when the wavelength conversion member 100 is placed in the liquid crystal display device. Furthermore, the external force applied from the side of the laminate 1 refers to, for example, a force applied when the wavelength conversion member is transported.

[0059] In the wavelength conversion member having the above configuration, the laminate 1 includes an outer laminate 1B located outside the first side surface 24. As a result, the outer laminate 1B protects the coating film 3 from external forces applied from the sides of the laminate 1, and can prevent the coating film 3 from being damaged by the external forces. As a result, a decrease in the wavelength conversion efficiency of the wavelength conversion member can be prevented. Similarly, the outer laminate 1B protects the inner laminate 1A from the external forces and prevents damage to the inner laminate 1A. In other words, the outer laminate 1B has a buffering effect against external forces applied from the sides of the laminate 1.

[0060] Furthermore, in the wavelength conversion member having the above configuration, a buffer material 4 may be disposed in the hole 2. This allows the buffer material 4 to further protect the coating film 3 and the inner laminate body 1A from external forces applied from the sides of the laminate body 1, and further suppresses damage to the coating film 3 and the inner laminate body 1A. As a result, it is possible to suppress a decrease in the wavelength conversion efficiency of the wavelength conversion member.

[0061] Furthermore, in the wavelength conversion member having the above configuration, the coating film 3 continuously covers the third side surface 34, the first side surface 24, and the second side surface 14. This makes it possible to prevent moisture and the like from penetrating into the laminate 1 through the boundary between the second barrier layer 30 and the wavelength conversion layer 20 and the boundary between the first barrier layer 10 and the wavelength conversion layer 20. Furthermore, the coating film 3 can increase the mutual adhesive strength between the first barrier layer 10, the wavelength conversion layer 20, and the second barrier layer 30. As a result, it is possible to prevent a decrease in the wavelength conversion efficiency of the wavelength conversion member.

[0062] In the wavelength conversion member having the above configuration, the hole 2 is provided in an annular shape and has an inner surface 2a covered with the coating film 3. This makes it possible to prevent moisture and the like from entering the inner laminate 1A, and to suppress a decrease in the wavelength conversion efficiency of the wavelength conversion member.

[0063] Next, the materials of the coating film 3, the wavelength conversion layer 20, the first barrier layer 10, and the second barrier layer 30 will be described in detail.

[0064] (Coating Film) The coating film 3 is, for example, a layer that acts as a barrier against moisture, oxygen, etc. The coating film 3 may include a first layer and a second layer disposed on the first layer. The first layer is, for example, made of at least one selected from the group consisting of a thermosetting urethane resin, a phenolic resin, a urea-melamine resin, an epoxy resin, an unsaturated polyester resin, an acrylic resin, and a silicone resin. The thermosetting urethane resin includes, for example, an acrylic polyol resin and an isocyanate prepolymer. The thermosetting urethane resin is, for example, a composite of an acrylic polyol resin containing a hydroxy group and an isocyanate compound having two or more NCO groups in the molecule.

[0065] The second layer is made of at least one material selected from the group consisting of vinylidene chloride resin, fluorine-based resin, and oxide. The vinylidene chloride resin is, for example, Saran (registered trademark) resin. The oxide is, for example, Al. ２ O ３ and SiO ２ When an oxide is used as the second layer, the adhesion between the laminate 1 and the oxide can be improved by using a composite of an acrylic polyol resin containing a hydroxy group and an isocyanate compound having at least two NCO groups in the molecule as the first layer. When a resin is used as the material for each of the first and second layers, the resin may be applied multiple times in layers.

[0066] The coating film 3 may also include, for example, a plating layer and an atomic layer deposition layer disposed on the plating layer. Such a coating film 3 can form a coating film with a uniform thickness. The plating layer may be, for example, a laminate of a plating primer and a copper plating. The atomic layer deposition layer may be, for example, an Al ２ O ３ and SiO ２ It is a layered structure.

[0067] Furthermore, the coating film 3 may include, for example, an oxygen plasma-treated layer and a chemical vapor deposition layer disposed on the oxygen plasma-treated layer. Such a coating film 3 can be formed with a uniform thickness. The chemical vapor deposition layer is, for example, a polyparaxylene layer. By employing a chemical vapor deposition layer, water repellency and gas barrier properties against gases such as water vapor and oxygen can be improved. Furthermore, by employing a chemical vapor deposition layer, heat resistance in the atmosphere can be improved. As an example, a coating film 3 having heat resistance up to approximately 300°C in the atmosphere can be formed. Furthermore, a coating film 3 including an oxygen plasma-treated layer and a chemical vapor deposition layer can be formed at room temperature and has high coverage on uneven surfaces.

[0068] Furthermore, the coating film 3 may contain a filler such as alumina or silica and have light reflectivity. This allows part of the incident light on the wavelength conversion member or part of the light emitted by quantum dots or the like contained in the wavelength conversion layer 20 to reach the inner surface 2a of the hole 2, and the light to be reflected by the light-reflective coating film 3. As a result, the amount of light emitted from the upper surface of the wavelength conversion member 100 can be increased.

[0069] Here, if the wavelength conversion layer 20 is exposed to a high temperature exceeding 90° C. for two hours or more, the wavelength conversion layer 20 may be damaged by heat, resulting in a decrease in wavelength conversion efficiency. In contrast, the example of the coating film 3 including the oxygen plasma treatment layer and the chemical vapor deposition layer can be cured and formed at a temperature of 80° C. or less, and therefore, heat damage to the wavelength conversion layer 20 can be suppressed when the coating film 3 is formed.

[0070] The coating film 3 may also be a cured resin layer made of a resin composition containing at least one functional material selected from the group consisting of a moisture remover (moisture scavenger), an oxygen remover (oxygen scavenger), an antioxidant, a filler, etc., which will be described later. The resin composition may contain, for example, an epoxy resin, an acrylic resin, etc. as a base material.

[0071] In one embodiment, the coating film 3 may be made of a filler that fills the pores 2. The filler may include a cured product of a curable resin. The curable resin may include a thermosetting resin such as a thermosetting urethane resin, a phenolic resin, a urea melamine resin, an epoxy resin, or a silicone resin, or may include a photocurable resin such as an unsaturated polyester resin or an acrylic resin. The filler may also include a gas barrier resin such as an ethylene-vinyl alcohol copolymer resin. Furthermore, the filler may include a filler such as alumina or silica, and may have light reflectivity.

[0072] (Wavelength Conversion Layer) As described above, the wavelength conversion layer 20 contains quantum dots. Quantum dots are semiconductor crystal particles with particle diameters of several nanometers to several tens of nanometers. When the size of a material is reduced to the nanometer order, electrons can only exist in a limited state within the material. As a result, the electronic state becomes discrete, and the band gap changes depending on the particle size. Quantum dots absorb light and emit light with a wavelength corresponding to the band gap energy. Therefore, by controlling the particle size, crystal composition, etc., the emission wavelength of the quantum dots can be controlled, and the quantum dots function as a wavelength conversion material. The particle diameter of the quantum dots contained in the wavelength conversion layer 20 may be, for example, 50 nm or less. The particle diameter of the quantum dots may preferably be 1 nm to 20 nm, 1.6 nm to 8 nm, or 2 nm to 7.5 nm.

[0073] The particle size of semiconductor nanoparticles constituting quantum dots refers to the longest line segment connecting any two points on the periphery of a particle observed in a transmission electron microscope (TEM) image and passing through the center of the particle. The average particle size of semiconductor nanoparticles refers to the arithmetic mean value of the particle sizes measured for semiconductor nanoparticles observed in a TEM image whose particle sizes can be measured.

[0074] When the semiconductor nanoparticles have a rod-like shape, the length of the minor axis is considered to be the particle size. Here, rod-like particles refer to particles that, when observed on a surface including the major axis, are observed as quadrilaterals (the cross section is circular, elliptical, or polygonal), including rectangular shapes long in one direction, ellipsoids, or polygonal shapes (e.g., pencil-like shapes), and the ratio of the length of the major axis to the length of the minor axis is greater than 1.2. For rod-like particles, the length of the major axis refers to the longest line segment among the line segments connecting any two points on the periphery of the particle in the case of an ellipse, and in the case of a quadrilateral or polygonal shape, refers to the longest line segment among the line segments connecting any two points on the periphery of the particle that is parallel to the longest side defining the periphery. The length of the minor axis refers to the longest line segment among the line segments connecting any two points on the periphery that is perpendicular to the line segment defining the length of the major axis. Specifically, the average particle size of semiconductor nanoparticles is determined by measuring the particle size of all measurable semiconductor nanoparticles observed in a TEM image at a magnification of 50,000 times or more and 150,000 times or less, and calculating the arithmetic mean of these particle sizes. Here, "measurable" particles are those whose entire outline can be observed in a TEM image. Therefore, particles that are "cut off" because some of the particles are not included in the imaging range in a TEM image are not measurable. When a single TEM image contains a total of 100 or more nanoparticles, the average particle size is determined using that single TEM image. When the number of nanoparticles contained in a single TEM image is small, the imaging location is changed, additional TEM images are acquired, and the particle sizes of 100 or more particles contained in two or more TEM images are measured to determine the average particle size.

[0075] Specific examples of quantum dots include perovskite quantum dots, chalcopyrite quantum dots, and III-V semiconductor quantum dots. The perovskite quantum dots may contain, for example, a compound represented by the following formula (1): [M １ ｗ A １ （１－ｗ） ] ｘ M ２ ｙ X ｚ (1)

[0076] In the formula (1), M １ represents a first element including at least one element selected from the group consisting of Cs, Rb, K, Na, and Li. １ represents a non-metallic cation containing at least one selected from the group consisting of an ammonium ion, a formamidinium ion, a guanidinium ion, an imidazolium ion, a pyridinium ion, a pyrrolidinium ion, and a protonated thiourea ion. ２ represents a second element containing at least one selected from the group consisting of Ge, Sn, Pb, Sb, and Bi. X represents an anion or a ligand containing at least one selected from the group consisting of chloride ions, bromide ions, iodide ions, cyanide ions, thiocyanate, isothiocyanate, and sulfide. x is a number from 1 to 4, y is a number from 1 to 2, z is a number from 3 to 9, and w is a number from 0 to 1. In the formula (1), the first element M １ and nonmetallic cation A １ When both of the first element M １ and nonmetallic cation A １ Both represent atomic groups that constitute a ligand.

[0077] The ammonium ion may be represented, for example, by formula (A-1) below. The formamidinium ion may be represented, for example, by formula (A-2) below. The guanidinium ion may be represented, for example, by formula (A-3) below. The protonated thiourea ion may be represented, for example, by formula (A-4) below. The imidazolium ion may be represented, for example, by formula (A-5) below. The pyridinium ion may be represented, for example, by formula (A-6) below. The pyrrolidinium ion may be represented, for example, by formula (A-7) below. In each formula representing a non-metal cation, R each independently represents at least one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a phenyl group, a benzyl group, a halogen atom, and a pseudohalogen. Any two R in each formula may be bonded to each other to form a nitrogen-containing aliphatic ring having 3 to 6 carbon atoms.

[0078] [R ４ N ＋ ] (A-1) [(NR ２ )２ RC ＋ ] (A-2) [(NR ２ ) ３ C ＋ ] (A-3) [(NR ２ ) ２ C ＋ -SR] (A-4)

[0079]

[0080] Perovskite quantum dots containing a compound having a composition represented by formula (1) emit green or red light when irradiated with light from a light source. Regarding green light, perovskite quantum dots may emit light having a peak emission wavelength in the range of 475 nm to 560 nm when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm. The peak emission wavelength of perovskite quantum dots emitting green light may preferably be in the range of 510 nm to 550 nm, or 525 nm to 535 nm. Regarding red light, perovskite quantum dots may emit light having a peak emission wavelength in the range of 600 nm to 680 nm when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm. The peak emission wavelength of perovskite quantum dots emitting red light may preferably be in the range of 610 nm to 670 nm, or 625 nm to 635 nm. The perovskite quantum dots may have an emission spectrum with a half-width of, for example, 35 nm or less, preferably 30 nm or less, or 25 nm or less. The perovskite quantum dots may exhibit band-edge emission in their emission spectrum.

[0081] The first aspect of the chalcopyrite quantum dots may include, for example, a first semiconductor containing silver (Ag), indium (In), gallium (Ga), and sulfur (S), and a second semiconductor containing Ga and S may be disposed on the surface of the first semiconductor. The second semiconductor may further contain Ag. The first semiconductor may be a semiconductor having a chalcopyrite structure containing Ag, In, Ga, and S. In the first aspect of the chalcopyrite quantum dots, an attachment containing a second semiconductor may be disposed on the surface of a particle containing the first semiconductor, or the attachment containing the second semiconductor may coat the particle containing the first semiconductor. Furthermore, the chalcopyrite quantum dots may have a core-shell structure in which, for example, a particle containing the first semiconductor serves as a core, and an attachment containing the second semiconductor serves as a shell, and the shell is disposed on the surface of the core. For details of the chalcopyrite quantum dots of the first aspect, reference may be made to the descriptions in, for example, JP 2018-044142 A and WO 2022 / 191032.

[0082] The first semiconductor contains at least Ag, and a part of Ag is substituted with copper (Cu), gold (Au), and an alkali metal (hereinafter, M ａ The first semiconductor may further contain at least one of the elements other than Ag (sometimes referred to as "substantially Ag"), or may be substantially composed of Ag. Here, "substantially" indicates that the ratio of the number of atoms of elements other than Ag substituting for Ag to the total number of atoms of Ag and elements other than Ag substituting for Ag is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less. Furthermore, the first semiconductor may substantially be composed of Ag and alkali metals as constituent elements. Here, "substantially" indicates that the ratio of the number of atoms of elements other than Ag and alkali metals substituting for Ag to the total number of atoms of Ag, alkali metals, and elements other than Ag and alkali metals substituting for Ag is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less. Incidentally, alkali metals include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs).

[0083] The first semiconductor may have a composition represented by the following formula (2a): (Ag ｐ Mａ （１－ｐ） ) ｑ In ｒ Ga （１－ｒ） S （ｑ＋３）／２ (2a) where p, q, and r satisfy 0<p≦1, 0.20<q≦1.2, and 0<r<1. M ａ indicates an alkali metal.

[0084] In the first embodiment of the chalcopyrite quantum dot, a second semiconductor may be disposed on the surface. The second semiconductor may include a semiconductor having a larger band gap energy than the first semiconductor. The second semiconductor may be a semiconductor consisting essentially of Ga and S. Alternatively, the second semiconductor may be a semiconductor consisting essentially of Ag, Ga, and S. Here, "substantially" indicates that, when the total number of atoms of all elements contained in the semiconductor containing Ga and S, or the semiconductor containing Ag, Ga, and S, is taken as 100%, the proportion of the number of atoms of elements other than Ga and S, or other than Ag, Ga, and S, is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less.

[0085] The chalcopyrite quantum dots of the first embodiment may exhibit band edge emission having a peak emission wavelength in the wavelength range of 475 nm to 560 nm (e.g., green) when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm, and the peak emission wavelength may preferably be in the range of 510 nm to 550 nm, or 525 nm to 535 nm. Furthermore, the chalcopyrite quantum dots of the first embodiment may have a half-width in their emission spectrum of, for example, 45 nm or less, preferably 40 nm or less, or 30 nm or less. The half-width may be, for example, 15 nm or more.

[0086] A second aspect of the chalcopyrite quantum dots may include, for example, a third semiconductor containing copper (Cu), silver (Ag), indium (In), gallium (Ga), and sulfur (S), and a fourth semiconductor containing Ga and S may be disposed on the surface of the third semiconductor. The fourth semiconductor may further contain Ag. The third semiconductor may be a semiconductor having a chalcopyrite structure containing Cu, Ag, In, Ga, and S. In the second aspect of the chalcopyrite quantum dots, an attachment containing the fourth semiconductor may be disposed on the surface of a particle containing the third semiconductor, or the attachment containing the fourth semiconductor may coat the particle containing the third semiconductor. Furthermore, the chalcopyrite quantum dots may have a core-shell structure in which, for example, a particle containing the third semiconductor serves as a core, and an attachment containing the fourth semiconductor serves as a shell, and the shell is disposed on the surface of the core. For details of the chalcopyrite quantum dots of the second aspect, reference can be made to the descriptions in, for example, WO 2020 / 162622 and WO 2023 / 013361.

[0087] The third semiconductor contains at least Ag and Cu, and a part of these is substituted with gold (Au) and an alkali metal (M ａ The third semiconductor may substantially contain Ag, Cu, and an alkali metal as constituent elements. Here, "substantially" indicates that the ratio of the number of atoms of elements other than Ag, Cu, and alkali metals to the total number of atoms of Ag, Cu, and alkali metals, and elements other than Ag, Cu, and alkali metals, is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less.

[0088] The third semiconductor may have a composition represented by the following formula (2b): (Ag ｓ Cu （１－ｓ） ) ｔ In ｕ Ga （１－ｕ） S （ｔ＋３）／２ (2b) where s, t, and u satisfy 0<s<1, 0.20<t≦1.2, and 0<u<1.

[0089] In the second embodiment of the chalcopyrite quantum dot, a fourth semiconductor may be disposed on the surface. The fourth semiconductor may include a semiconductor having a band gap energy larger than that of the third semiconductor. The fourth semiconductor may be a semiconductor consisting essentially of Ga and S. Alternatively, the fourth semiconductor may be a semiconductor consisting essentially of Ag, Ga, and S. Here, "substantially" indicates that, when the total number of atoms of all elements contained in the semiconductor containing Ga and S, or the semiconductor containing Ag, Ga, and S, is taken as 100%, the proportion of the number of atoms of elements other than Ga and S, or other than Ag, Ga, and S, is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less.

[0090] The chalcopyrite quantum dots of the second embodiment may exhibit band edge emission having a peak emission wavelength in the wavelength range of 600 nm to 680 nm (e.g., red) when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm, and the peak emission wavelength may preferably be in the range of 610 nm to 670 nm, or 625 nm to 635 nm. Furthermore, the chalcopyrite quantum dots of the second embodiment may have a half-width in their emission spectrum of, for example, 60 nm or less, preferably 40 nm or less, or 30 nm or less. The half-width may be, for example, 15 nm or more.

[0091] A third aspect of the chalcopyrite quantum dots may include, for example, a fifth semiconductor containing silver (Ag), gallium (Ga), and selenium (Se), and a sixth semiconductor containing zinc (Zn) and sulfur (S) may be disposed on the surface of the fifth semiconductor. The fifth semiconductor may contain at least Ag, Ga, and Se, and may be partially substituted with indium (In) and sulfur (S). The sixth semiconductor may further contain at least one of Ga and Se. The fifth semiconductor may be a semiconductor having a chalcopyrite structure containing Ag, Ga, and Se. In the third aspect of the chalcopyrite quantum dots, an attachment containing a sixth semiconductor may be disposed on the surface of a particle containing the fifth semiconductor, or the attachment containing the sixth semiconductor may coat the particle containing the fifth semiconductor. Furthermore, the chalcopyrite quantum dots may have a core-shell structure in which, for example, a particle containing the fifth semiconductor serves as a core, and an attachment containing the sixth semiconductor serves as a shell, and the shell is disposed on the surface of the core. For details of the chalcopyrite quantum dots of the third aspect, reference can be made to the descriptions in, for example, International Publication No. 2021 / 039290.

[0092] The fifth semiconductor may have a composition represented by the following formula (2c), for example: AgIn ｘ Ga １－ｘ S ｙ Se １－ｙ (2c) where x and y satisfy 0≦x<1 and 0≦y≦1.

[0093] In a third aspect of the chalcopyrite quantum dot, a sixth semiconductor may be disposed on the surface. The sixth semiconductor may include a semiconductor having a band gap energy larger than that of the fifth semiconductor. The sixth semiconductor may be a semiconductor consisting essentially of Zn and S. Here, "substantially" indicates that, when the total number of atoms of all elements contained in the semiconductor, including Zn and S, is taken as 100%, the proportion of the number of atoms of elements other than Zn and S is, for example, 10% or less, preferably 5% or less, and more preferably 1% or less.

[0094] The chalcopyrite quantum dots of the third embodiment may exhibit band edge emission having a peak emission wavelength in the wavelength range of 600 nm to 680 nm (e.g., red) when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm, and the peak emission wavelength may preferably be in the range of 610 nm to 670 nm, or 625 nm to 635 nm. Furthermore, the chalcopyrite quantum dots of the third embodiment may have a half-width in their emission spectrum of, for example, 50 nm or less, preferably 40 nm or less, or 30 nm or less. The half-width may be, for example, 15 nm or more.

[0095] The III-V semiconductor quantum dots may include semiconductor nanoparticles containing a III-V semiconductor, such as AlN, AlP, AlAs, AlSb, GaAs, GaP, GaN, GaSb, InN, InAs, InP, InSb, TiN, TiP, TiAs, and TiSb. Indium phosphide (InP) is preferred.

[0096] The III-V semiconductor quantum dots may have an attachment containing a seventh semiconductor different from the III-V semiconductor constituting the semiconductor nanoparticles disposed on the surface of semiconductor nanoparticles containing a III-V semiconductor, or the attachment containing the seventh semiconductor may coat the particles containing a III-V semiconductor. Furthermore, the III-V semiconductor quantum dots may have a core-shell structure in which, for example, a particle containing a III-V semiconductor serves as a core and an attachment containing the seventh semiconductor serves as a shell, with the shell disposed on the surface of the core. The seventh semiconductor may be a semiconductor having a larger band gap energy than the III-V semiconductor. Examples of combinations of a III-V semiconductor and a seventh semiconductor include InP / ZnS, GaP / ZnS, InN / GaN, InP / CdSSe, InP / ZnSeTe, InGaP / ZnSe, InGaP / ZnS, InP / ZnSTe, InGaP / ZnSTe, and InGaP / ZnSSe.

[0097] For example, III-V semiconductor quantum dots may emit green or red light when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm. Green-emitting III-V semiconductor quantum dots may exhibit band-edge emission having a peak emission wavelength in the range of, for example, 475 nm to 560 nm when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm. The peak emission wavelength may preferably be in the range of 510 nm to 550 nm, or 525 nm to 535 nm. Furthermore, red-emitting III-V semiconductor quantum dots may exhibit band-edge emission having a peak emission wavelength in the wavelength range of, for example, 600 nm to 680 nm when irradiated with light from a light source having a peak emission wavelength in the range of, for example, 380 nm to 545 nm. The peak emission wavelength may preferably be in the range of 610 nm to 670 nm, or 625 nm to 635 nm. The half width of the emission spectrum of the III-V semiconductor quantum dots may be, for example, 60 nm or less, preferably 40 nm or less, or 30 nm or less. The half width may be, for example, 15 nm or more.

[0098] The quantum dots may contain quantum dots other than perovskite-based quantum dots, chalcopyrite-based quantum dots, and III-V semiconductor-based quantum dots, as necessary. Examples of other quantum dots include particles containing at least one semiconductor selected from the group consisting of II-VI semiconductors, IV-VI semiconductors, and IV semiconductors.

[0099] Specific examples of II-VI group semiconductors include CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, and the like. Specific examples of IV-VI semiconductors include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, etc. Specific examples of IV semiconductors include Si, Ge, SiC, SiGe, etc.

[0100] The quantum dots may have a surface modifier disposed on their surfaces. Specific examples of the surface modifier include amino alcohols having 2 to 20 carbon atoms; ionic surface modifiers; nonionic surface modifiers; nitrogen-containing compounds having a hydrocarbon group having 4 to 20 carbon atoms; sulfur-containing compounds having a hydrocarbon group having 4 to 20 carbon atoms; oxygen-containing compounds having a hydrocarbon group having 4 to 20 carbon atoms; phosphorus-containing compounds having a hydrocarbon group having 4 to 20 carbon atoms; and halides containing at least one selected from the group consisting of Group 2 elements, Group 12 elements, and Group 13 elements. The surface modifiers may be used alone or in combination of two or more different types.

[0101] The amino alcohol used as a surface modifier may be any compound having an amino group and an alcoholic hydroxyl group, and including a hydrocarbon group having 2 to 20 carbon atoms. The number of carbon atoms in the amino alcohol is preferably 10 or less, more preferably 6 or less. The hydrocarbon group constituting the amino alcohol may be derived from a hydrocarbon such as a linear, branched, or cyclic alkane, alkene, or alkyne. "Derived from a hydrocarbon" means that the hydrocarbon group is formed by removing at least two hydrogen atoms from a hydrocarbon. Specific examples of amino alcohols include aminoethanol, aminopropanol, aminobutanol, aminopentanol, aminohexanol, and aminooctanol. For example, when the amino group of the amino alcohol is bonded to the surface of a semiconductor nanoparticle and the hydroxyl group is exposed on the opposite outermost surface of the particle, the polarity of the semiconductor nanoparticle changes, improving dispersibility in alcoholic solvents (e.g., methanol, ethanol, propanol, butanol, etc.).

[0102] Examples of ionic surface modifiers used as surface modifiers include nitrogen-containing compounds, sulfur-containing compounds, and oxygen-containing compounds having an ionic functional group in the molecule. The ionic functional group may be either cationic or anionic, and preferably has at least a cationic group. Specific examples of surface modifiers and surface modification methods can be found in, for example, Chemistry Letters, Vol. 45, pp. 898-900, 2016.

[0103] The ionic surface modifier may be, for example, a sulfur-containing compound having a tertiary or quaternary alkylamino group. The number of carbon atoms in the alkyl group of the alkylamino group may be, for example, 1 to 4. The sulfur-containing compound may also be an alkyl or alkenyl thiol having 2 to 20 carbon atoms. Specific examples of the ionic surface modifier include hydrogen halide salts of dimethylaminoethanethiol, halogen salts of trimethylammoniumethanethiol, hydrogen halide salts of dimethylaminobutanethiol, and halogen salts of trimethylammoniumbutanethiol.

[0104] Examples of nonionic surface modifiers used as surface modifiers include nitrogen-containing compounds, sulfur-containing compounds, and oxygen-containing compounds having nonionic functional groups including alkylene glycol units and alkylene glycol monoalkyl ether units. The number of carbon atoms in the alkylene group in the alkylene glycol unit may be, for example, 2 to 8, preferably 2 to 4. The number of repeating alkylene glycol units may be, for example, 1 to 20, preferably 2 to 10. The nitrogen-containing compound constituting the nonionic surface modifier may have an amino group, the sulfur-containing compound may have a thiol group, and the oxygen-containing compound may have a hydroxyl group. Specific examples of nonionic surface modifiers include methoxytriethyleneoxyethanethiol and methoxyhexaethyleneoxyethanethiol.

[0105] Examples of nitrogen-containing compounds having a hydrocarbon group with 4 to 20 carbon atoms include amines and amides. Examples of sulfur-containing compounds having a hydrocarbon group with 4 to 20 carbon atoms include thiols. Examples of oxygen-containing compounds having a hydrocarbon group with 4 to 20 carbon atoms include carboxylic acids, alcohols, ethers, aldehydes, and ketones. Examples of phosphorus-containing compounds having a hydrocarbon group with 4 to 20 carbon atoms include trialkylphosphines, triarylphosphines, trialkylphosphine oxides, and triarylphosphine oxides.

[0106] Examples of the halide containing at least one element selected from the group consisting of Group 2 elements, Group 12 elements, and Group 13 elements include magnesium chloride, calcium chloride, zinc chloride, cadmium chloride, aluminum chloride, and gallium chloride.

[0107] The quantum dots contained in the wavelength conversion layer 20 may include at least one type selected from the group consisting of first quantum dots having an emission peak wavelength in the wavelength range of 475 nm to 560 nm and second quantum dots having an emission peak wavelength in the wavelength range of 600 nm to 680 nm. The quantum dots may also include at least one type of first quantum dot and at least one type of second quantum dot. The first quantum dots may include at least one type selected from the group consisting of perovskite-based quantum dots, III-V semiconductor-based quantum dots, and the first aspect of chalcopyrite-based quantum dots. Preferably, the first quantum dots may include at least one type selected from the group consisting of perovskite-based quantum dots and the first aspect of chalcopyrite-based quantum dots. The second quantum dots may include at least one type selected from the group consisting of perovskite-based quantum dots, the second aspect of chalcopyrite-based quantum dots, the third aspect of chalcopyrite-based quantum dots, and the III-V semiconductor-based quantum dots. Preferably, the second quantum dots may comprise at least one selected from the group consisting of the chalcopyrite quantum dots of the second aspect, the chalcopyrite quantum dots of the third aspect, and III-V semiconductor quantum dots. When the wavelength conversion layer 20 comprises the first quantum dots and the second quantum dots, green light and red light are emitted from the first quantum dots and the second quantum dots, respectively, when the wavelength conversion layer 20 is irradiated with blue light having an emission peak wavelength in the range of, for example, 380 nm to 545 nm. As a result, white light is obtained by mixing the green light and red light emitted from the first quantum dots and the second quantum dots with the blue light that passes through the wavelength conversion layer 20.

[0108] The wavelength conversion layer constituting the laminate 1 may be one layer or two or more layers. When the wavelength conversion layer 20 constituting the laminate 1 is, for example, two layers, one wavelength conversion layer 20 may contain first quantum dots and the other wavelength conversion layer 20 may contain second quantum dots. The wavelength conversion layer 20 may include, for example, a layer containing chalcopyrite quantum dots that emit green light and a layer containing chalcopyrite quantum dots that emit red light. The wavelength conversion layer 20 may also include a layer containing chalcopyrite quantum dots that emit green light and a layer containing III-V semiconductor quantum dots that emit red light. The wavelength conversion layer 20 may also include a layer containing perovskite quantum dots that emit green light and a layer containing III-V semiconductor quantum dots that emit red light. The wavelength conversion layer 20 may include a layer containing perovskite-based quantum dots that emit green light and a layer containing chalcopyrite-based quantum dots that emit red light. Alternatively, the wavelength conversion layer may include a layer containing chalcopyrite-based quantum dots that emit green light and a layer containing III-V semiconductor-based quantum dots that emit red light. Alternatively, the wavelength conversion layer may include a layer containing perovskite-based quantum dots that emit green light and a layer containing III-V semiconductor-based quantum dots that emit red light.

[0109] The wavelength conversion layer 20 may contain, in addition to quantum dots, at least one phosphor as a light-emitting material other than quantum dots, as needed. Examples of the phosphor include yttrium aluminum garnet phosphors (e.g., (Y, Gd) ３ (Al, Ga) ５ O １２ :Ce), lutetium aluminum garnet phosphors (e.g., Lu ３ (Al, Ga) ５ O １２ :Ce), terbium aluminum garnet phosphors (e.g., Tb ３ (Al, Ga) ５ O １２ :Ce), CCA-based phosphors (e.g., Ca １０ (P.O. ４ ) ６ Cl ２ :Eu), SAE-based phosphors (e.g., Sr４ Al １４ O ２５ :Eu), chlorosilicate phosphors (e.g., Ca ８ MgSi ４ O １６ Cl ２ :Eu), silicate-based phosphors (e.g., (Ba, Sr, Ca, Mg) ２ SiO ４ :Eu), β-sialon-based phosphors (e.g., (Si, Al) ３ (O, N) ４ :Eu) or α-sialon-based phosphor (e.g., Ca(Si,Al) １２ (O, N) １６ oxynitride phosphors such as (La,Y) ３ Si ６ N １１ :Ce), BSESN-based phosphors (e.g., (Ba, Sr) ２ Si ５ N ８ :Eu), SLA-based phosphors (e.g., SrLiAl ３ N ４ :Eu), CASN-based phosphors (e.g., CaAlSiN ３ :Eu) or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN ３ nitride-based phosphors such as KSF-based phosphors (e.g., K ２ SiF ６ :Mn), KSAF-based phosphors (e.g., K ２ (Si １－ｘ Al ｘ ) F ６－ｘ :Mn where x satisfies 0<x<1) or MGF-based phosphor (for example, 3.5MgO.0.5MgF ２ GeO ２ Fluoride-based phosphors such as fluoride-based phosphors (e.g., ZnO, ZnO, Mn, ZnO ...

[0110] The wavelength conversion layer 20 may include, for example, chalcopyrite quantum dots that emit green light and a manganese-activated fluoride complex phosphor. The wavelength conversion layer 20 may include perovskite quantum dots that emit green light and a manganese-activated fluoride complex phosphor. The wavelength conversion layer may also include a layer containing chalcopyrite quantum dots that emit green light and a layer containing a manganese-activated fluoride complex phosphor that emits red light. The wavelength conversion layer may also include a layer containing perovskite quantum dots that emit green light and a layer containing a manganese-activated fluoride complex phosphor that emits red light.

[0111] The wavelength conversion layer 20 may contain a cured resin in addition to the quantum dots. The cured resin may be a cured product of a photocurable composition described below. The content of the quantum dots contained in the wavelength conversion layer 20 may be, for example, 0.01% by mass or more and 1.0% by mass or less, and preferably 0.05% by mass or more and 0.5% by mass or less, or 0.1% by mass or more and 0.5% by mass or less, relative to the total amount of the cured resin. A quantum dot content of 0.01% by mass or more tends to provide sufficient luminescence intensity upon light irradiation, while a quantum dot content of 1.0% by mass or less tends to suppress aggregation of the quantum dots and reduce color unevenness.

[0112] The photocurable composition that forms the cured resin may contain, for example, a (meth)acrylic compound. The (meth)acrylic compound may be a monofunctional (meth)acrylic compound having one (meth)acryloyl group per molecule, or a polyfunctional (meth)acrylic compound having two or more (meth)acryloyl groups per molecule. As the (meth)acrylic compound, one type may be used alone, or two or more types may be used in combination, and a monofunctional (meth)acrylic compound and a polyfunctional (meth)acrylic compound may be used in combination. Here, the (meth)acrylic compound includes an acrylic compound, a methacrylic compound, and a mixture thereof, and the same applies to similar notations.

[0113] (First Barrier Layer and Second Barrier Layer) The first barrier layer 10 and the second barrier layer 30 may be made of the same material. The oxygen permeability of the first barrier layer 10 and the second barrier layer 30 may be, for example, 0.5 mL / m ２ 24h atm) or less, and preferably 0.3 mL / (m ２ ・24h・atm) or less, or 0.1mL / (m ２ The oxygen permeability of the first barrier layer 10 and the second barrier layer 30 can be measured using an oxygen permeability measuring device (for example, OX-TRAN manufactured by MOCON) under conditions of a temperature of 23°C and a relative humidity of 65%.

[0114] The barrier film having the inorganic layer that constitutes the first barrier layer 10 and the second barrier layer 30 may include, for example, a substrate film and an inorganic layer provided on at least one main surface of the substrate film. Alternatively, for example, the first barrier layer 10 and the second barrier layer 30 may be a laminate film including two substrate films and an inorganic layer disposed between the two substrate films. Examples of materials that can be used for the substrate film include thermoplastic resins such as polyester (e.g., polyethylene terephthalate, polyethylene naphthalate), cellulose triacetate, cellulose diacetate, cellulose acetate butyrate, polyamide, polyimide, polyethersulfone, polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone, polymethyl methacrylate, polycarbonate, and polyurethane. Preferred materials for the substrate film include polyester and cellulose triacetate.

[0115] The average thickness of the substrate film may be, for example, 10 μm or more and 150 μm or less, preferably 20 μm or more and 125 μm or less. When the average thickness of the substrate film is 10 μm or more, the occurrence of wrinkles and folds during assembly and handling of the wavelength conversion member is effectively suppressed. Furthermore, when the average thickness is 150 μm or less, it can contribute to reducing the weight and thickness of the image display device.

[0116] The substrate film may be composed of a single film or a laminated film composed of multiple films. Depending on the application, such a laminated film may be composed of multiple layers of films made of the same type of constituent material, or multiple layers of films made of different types of constituent material.

[0117] The inorganic layer may be a film made of an inorganic compound such as an oxide, a nitride, an oxynitride, or a carbide. Specific examples include metal oxides such as aluminum oxide, magnesium oxide, tantalum oxide, zirconium oxide, titanium oxide, and indium tin oxide (ITO); metal nitrides such as aluminum nitride; metal carbides such as aluminum carbide; silicon oxides such as silicon oxide, silicon oxynitride, silicon oxycarbide, and silicon oxynitride carbide; silicon nitrides such as silicon nitride and silicon carbide nitride; silicon carbides such as silicon carbide; and hydrides thereof. The inorganic layer may be made of one type of inorganic compound, or may be made of two or more types of inorganic compounds.

[0118] The average thickness of the inorganic layer may be, for example, 10 nm or more and 200 nm or less, preferably 10 nm or more and 100 nm or less, or 15 nm or more and 75 nm or less.

[0119] The inorganic layer may be formed by a known method depending on the material used, such as a plasma CVD method such as CCP-CVD or ICP-CVD, a sputtering method such as magnetron sputtering or reactive sputtering, a vacuum deposition method, or a vapor phase deposition method.

[0120] The surfaces of the first barrier layer 10 and the second barrier layer 30 may be prism-processed. For example, an array of prisms may be formed on the surface of the second barrier layer 30 located on the exit surface side of the wavelength conversion member 100. This allows light to be efficiently emitted from the exit surface of the wavelength conversion member 100. The first barrier layer 10 located on the incident surface side of the wavelength conversion member 100 may be provided with a reflection mechanism that transmits light of a specific wavelength and reflects light of wavelengths other than the specific wavelength. The first barrier layer 10 may include, for example, a dichroic mirror layer. This allows light reflected within the wavelength conversion member 100 that returns to the incident surface side of the wavelength conversion member 100 to be reflected toward the exit surface side by the reflection mechanism. The reflection mechanism may also be provided in the second barrier layer 30.

[0121] When the first barrier layer 10 and the second barrier layer 30 each include a primary barrier layer 15 and an intermediate layer 16 , the above-mentioned materials for the first barrier layer 10 and the second barrier layer 30 can be applied to the primary barrier layer 15 .

[0122] The intermediate layer 16 may contain, as a base material, a cured resin having a structure similar to that of the cured resin exemplified in the description of the wavelength conversion layer. The intermediate layer 16 may further contain at least one functional material in addition to the cured resin. Examples of the functional material include a moisture remover (moisture scavenger), an oxygen remover (oxygen scavenger), an antioxidant, etc., and the intermediate layer 16 may contain at least one selected from the group consisting of these.

[0123] Examples of moisture removers include oxides of Group 2 elements such as magnesium oxide and calcium oxide, hydrotalcite, aluminosilicates (e.g., zeolites), and silicon oxides (e.g., silica gel). Here, the hydrotalcite may be a compound having a composition represented by the following formula (3): [M ３ １－ｘ M ４ ｘ (OH) ２ ] ｘ＋ [A ｎ－ ｘ / ｎ ・mH ２ O] ｘ－ (3)

[0124] In formula (3), M ３ is Mg ２＋ , Mn ２＋ , Fe ２＋ , Co ２＋ , Ni ２＋ , Cu ２＋ , Zn ２＋ It represents a divalent metal ion such as M ４ is Fe ３＋ , Cr ３＋ , Co ３＋ , In ３＋ It indicates a trivalent metal ion such as A. ｎ－ OH － , F － , Cl － ,Br － , NO ３ － , CO ３ ２－ , S.O. ４ ２－ , Fe(CN) ６ ３－ , C.H. ３ COO － , oxalate, salicylate, etc., where x satisfies the relationship 0<x≦0.33, and m is a positive number.

[0125] Examples of oxygen removers include ceria-zirconia solid solution (CZ solid solution), etc. Examples of antioxidants include ascorbic acid, catechin, dibutylhydroxytoluene, tocopherol, butylhydroxyanisole, etc.

[0126] The content of the functional material in the intermediate layer 16 may be, for example, 0.1 parts by mass to 20 parts by mass, and preferably 0.1 parts by mass to 15 parts by mass, or 0.1 parts by mass to 2 parts by mass, relative to 100 parts by mass of the cured resin. By setting the content of the functional material in the intermediate layer 16 within the above range, it is possible to suppress the intrusion of moisture contained in the outside air, etc., while suppressing a decrease in the luminous efficiency of the wavelength conversion member caused by the functional material.

[0127] 2. Embodiment 2 As shown in Fig. 2, the wavelength conversion member 200 according to embodiment 2 differs from the wavelength conversion member 100 according to embodiment 1 in that the coating film 3 that covers the second side surface 214 of the first barrier layer 210, the first side surface 224 of the wavelength conversion layer 220, and the third side surface 234 of the second barrier layer 230 is exposed on the outer circumferential surface of the laminate 201. The outer circumferential surface of the laminate 201 refers to the entire surface of the laminate 201 when viewed from the side. In this case, the outer circumferential surface of the laminate 201 can also be said to refer to the entire surface of the laminate 201 when viewed from a direction perpendicular to the thickness direction Z.

[0128] Compared to the wavelength conversion member 100 of the first embodiment, the wavelength conversion member 200 has a shape in which, for example, outer peripheral portions of the second barrier layer 230, the wavelength conversion layer 220, and the first barrier layer 210 have been removed. The third side surface 234 of the second barrier layer 230 can also be considered a third end surface of the second barrier layer 230, and the first side surface 224 of the wavelength conversion layer 220 can also be considered a second end surface of the wavelength conversion layer 20. That is, in the second embodiment, the second end surface and the third end surface are located inside the first end surface 13. In the example shown in FIG. 2 , the third side surface 234, the first side surface 224, and the second side surface 214 extend intersecting with the thickness direction Z. However, they may extend along the thickness direction Z as long as the coating film 3 is located inside the first end surface 13.

[0129] The first barrier layer 210 may have a step 17 between the second side surface 214 and the first end face 13. The surface of the step 17 may be exposed on the outer peripheral surface of the stack 201 and covered with a coating film 3. The coating film 3 covering the step 17 is located, for example, inside the first end face 13.

[0130] The wavelength conversion member 200 having the above configuration can receive an external force applied from the side of the laminate 201 at the first end face 13. This protects the coating film 3 from the external force and prevents damage to the coating film 3. Furthermore, in the wavelength conversion member 200 according to the second embodiment, it is easy to make the opening of the hole large in the step of providing the hole, which will be described later. This makes it easy to arrange the coating film 3 by, for example, sputtering, vacuum deposition, or the like in the step of arranging the coating film 3, and allows the coating film 3 to be formed with a uniform thickness.

[0131] It is preferable that at least the region of the stack 201 that contacts the coating film 3 has an uneven shape. Specifically, it is preferable that the second side surface 214 of the first barrier layer 210, the first side surface 224 of the wavelength conversion layer 220, and the third side surface 234 of the second barrier layer 230 have an uneven shape. By providing an uneven shape in these regions, the bonding strength between these regions and the coating film 3 is improved. Such an uneven shape can be formed by, for example, wet blasting or sand blasting. The same applies to the other embodiments described below.

[0132] 3 , a wavelength conversion member 300 according to the third embodiment differs from the wavelength conversion member 100 according to the first embodiment in that a coating film 3 is disposed by filling the holes 2 and further covers the sixth main surface 32. Furthermore, the wavelength conversion member 300 according to the third embodiment differs from the wavelength conversion member 100 according to the first embodiment in that it further includes a third barrier layer 40 laminated on the sixth main surface 32.

[0133] The third barrier layer 40 has a seventh major surface 41 and an eighth major surface 42. The eighth major surface 42 is located opposite the seventh major surface 41 in the thickness direction Z. The seventh major surface 41 and the eighth major surface 42 are, for example, approximately flat surfaces perpendicular to the thickness direction Z. The material of the third barrier layer 40 can be the same as the material of the first barrier layer 10 and the second barrier layer 30. The third barrier layer 40 is disposed on the second barrier layer 30 via the coating film 3. It can also be said that the seventh major surface 41 of the third barrier layer 40 is disposed opposite the sixth major surface 32 of the second barrier layer 30.

[0134] The coating film 3 is disposed by filling the holes 2 and covers the inner surfaces 2a of the holes 2. The coating film 3 is further disposed between the second barrier layer 30 and the third barrier layer 40. The coating film 3 covers the sixth main surface 32 of the second barrier layer 30 and the seventh main surface 41 of the third barrier layer 40. The average thickness of the coating film 3 disposed between the second barrier layer 30 and the third barrier layer 40 may be, for example, 1% to 50% of the average thickness of the first barrier layer 10, and preferably 5% to 10%. The average thickness of the coating film 3 may be, for example, 0.2 μm to 100 μm, and preferably 2 μm to 50 μm.

[0135] The coating film 3 covering the sixth main surface 32 of the second barrier layer 30 and the coating film 3 filling the holes 2 may be made of the same material or different materials. The coating film 3 continuously covers, for example, the inner surfaces 2 a of the holes 2 and the sixth main surface 32.

[0136] The wavelength conversion member 300 having the above configuration can further improve the barrier performance of the laminate 301. Specifically, the third barrier layer 40, the coating film 3, and the second barrier layer 30 can prevent moisture, oxygen, and the like from penetrating into the wavelength conversion layer 20 from the upper surface side of the wavelength conversion member 300, thereby improving the barrier performance. Furthermore, the wavelength conversion member 300 having the above configuration can further increase the adhesive strength between the layers included in the laminate 301 due to the coating film 3.

[0137] 4. Embodiment 4 As shown in Fig. 4 , a wavelength conversion member 400 according to embodiment 4 differs from the wavelength conversion member 100 according to embodiment 1 in that the coating film 3 is disposed to fill the holes 2 and to cover the fourth main surface 22. The wavelength conversion member 400 according to embodiment 4 also differs from the wavelength conversion member 100 according to embodiment 1 in that the holes 2 are provided over the wavelength conversion layer 20 and part of the first barrier layer 10, but are not provided in the second barrier layer 30.

[0138] The coating film 3 is disposed by filling the hole 2 and covers the inner surface 2a of the hole 2. In embodiment 4, the inner side surface 2c includes a first side surface 24 and a second side surface 14. The coating film 3 is further disposed between the wavelength conversion layer 20 and the second barrier layer 30. The second barrier layer 30 is disposed on the wavelength conversion layer 20 via the coating film 3. It can also be said that the second barrier layer 30 is disposed such that its fifth main surface 31 faces the fourth main surface 22 of the wavelength conversion layer 20. The coating film 3 covers the fourth main surface 22 of the wavelength conversion layer 20 and the fifth main surface 31 of the second barrier layer 30. The average thickness of the coating film 3 disposed between the wavelength conversion layer 20 and the second barrier layer 30 may be 1% to 50% of the average thickness of the first barrier layer 10, and preferably 5% to 10%. The average thickness of the coating film 3 may be, for example, 0.2 μm or more and 100 μm or less, and preferably 2 μm or more and 50 μm or less.

[0139] The coating film 3 covering the fourth main surface 22 of the wavelength conversion layer 20 and the coating film 3 filling the holes 2 may be made of the same material or different materials. For example, the coating film 3 covering the fourth main surface 22 and the coating film 3 filling the holes 2 are made of the same material, and the coating film 3 continuously covers the inner surface 2 a of the holes 2 and the fourth main surface 22.

[0140] The wavelength conversion member 400 having the above configuration can further improve the barrier performance of the laminate 401. Specifically, the second barrier layer 30 and the coating film 3 can prevent moisture, oxygen, and the like from entering the wavelength conversion layer 20 from the upper surface side of the wavelength conversion member 400, thereby improving the barrier performance.

[0141] 5. Manufacturing Method 1 A method for manufacturing the wavelength conversion member 100 of Embodiment 1 (hereinafter also referred to as Manufacturing Method 1) will be described. Manufacturing Method 1 may include: (1-1) preparing a laminate sheet; (1-2) forming holes; (1-3) covering the inner surfaces of the holes with a coating film; and (1-4) forming a spare wavelength conversion member including holes. Manufacturing Method 1 may further include: (1-5) obtaining a wavelength conversion member from the spare wavelength conversion member.

[0142] 5A , a laminate sheet 501 prepared in this step includes a first barrier sheet 510, a wavelength conversion sheet 520, and a second barrier sheet 530. The first barrier sheet 510, the wavelength conversion sheet 520, and the second barrier sheet 530 are arranged in this order in the thickness direction Z.

[0143] The first barrier sheet 510 includes a first major surface 511 and a second major surface 512 located opposite the first major surface 511. The first major surface 511 and the second major surface 512 are disposed opposite to each other in the thickness direction Z. The first barrier sheet 510 may include a main barrier sheet and an intermediate sheet. The intermediate sheet is laminated between the main barrier sheet and the wavelength conversion sheet 520.

[0144] The wavelength conversion sheet 520 includes a third main surface 521 and a fourth main surface 522 located opposite the third main surface 521. The third main surface 521 and the fourth main surface 522 are arranged opposite to each other in the thickness direction Z. The wavelength conversion sheet 520 is arranged on the first barrier sheet 510 with the third main surface 521 facing the second main surface 512 of the first barrier sheet 510. The wavelength conversion sheet 520 includes quantum dots.

[0145] The second barrier sheet 530 includes a fifth major surface 531 and a sixth major surface 532 located opposite the fifth major surface 531. The fifth major surface 531 and the sixth major surface 532 are arranged opposite to each other in the thickness direction Z. The second barrier sheet 530 is arranged on the wavelength conversion sheet 520 with the fifth major surface 531 facing the fourth major surface 522 of the wavelength conversion sheet 520.

[0146] The laminate sheet 501 can be produced, for example, as follows: A photocurable composition, which is a material for the wavelength-converting sheet 520, is applied to the surface of a continuously conveyed film-like first barrier sheet 510 to form a first composition layer. Examples of methods for applying the photocurable composition include gravure coating, die coating, curtain coating, extrusion coating, rod coating, and roll coating. Next, a film-like second barrier sheet 530 is laminated on the first composition layer. This produces a precursor of the laminate sheet 501 in which the first barrier sheet 510, the first composition layer, and the second barrier sheet 530 are laminated in this order. Next, light is irradiated from either the first barrier sheet 510 side and / or the second barrier sheet 530 side to cure the first composition layer and form the wavelength-converting sheet 520, thereby producing a laminate sheet in which the first barrier sheet 510, the wavelength-converting sheet 520, and the second barrier sheet 530 are laminated in this order. In this case, if necessary, the first composition layer may be subjected to drying treatment, heat treatment, etc. before being irradiated with light. The laminate sheet 501 may be prepared by the above-mentioned manufacturing method, or may be prepared by receiving it.

[0147] The laminate sheet 501 may further include a first protective sheet 551 covering the first main surface 511 and a second protective sheet 552 covering the sixth main surface 532. The material of the first protective sheet 551 and the second protective sheet 552 is, for example, a polyimide film whose surface is coated with an acrylic resin or a silicone resin. The first protective sheet 551 and the second protective sheet 552 are used to manufacture the wavelength conversion member and are removed in a later process. The protective sheet arranged on the side where the laser light is incident prevents resin debris generated during fusing from adhering to the surface of the laminate sheet 501 when the laminate sheet 501 is fusing with the laser light, for example.

[0148] (1-2) Step of Forming Holes As shown in FIG. 5B , in this step, holes 2 are formed in the laminate sheet 501. The holes 2 are formed across the second barrier sheet 530, the wavelength conversion sheet 520, and a part of the first barrier sheet 510. The holes 2 have an inner surface 2a. The inner surface 2a includes a third side surface 34, a first side surface 24, and a second side surface 14. The third side surface 34 connects the fifth main surface 531 and the sixth main surface 532. The first side surface 24 connects the third main surface 521 and the fourth main surface 522. The second side surface 14 connects to the second main surface 512. The inner surface 2a further includes a bottom surface 2b made of the first barrier sheet 510. The holes 2 are formed, for example, along the outer periphery of the spare wavelength conversion member 505 (described later) when viewed from above. The holes 2 may be formed in a ring shape along the outer periphery.

[0149] The holes 2 are formed along the thickness direction Z. The holes 2 are formed by removing parts of the second protective sheet 552, the second barrier sheet 530, the wavelength conversion sheet 520, and the first barrier sheet 510, for example, in the thickness direction Z. In this specification, removing parts of the laminate sheet 501 in this manner is also referred to as half-cutting. The holes 2 do not reach the first main surface 511 of the first barrier sheet 510 or the first protective sheet 551.

[0150] The holes 2 are formed, for example, by half-cutting the laminate sheet 501 by laser processing. The type of laser may be any, as long as the wavelength of the laser light includes a wavelength range in which the first barrier layer 10, the wavelength conversion layer 20, and the second barrier layer 30 are absorbed. Forming the holes 2 by laser processing makes it possible to make the inner surface 2 a smooth surface. The laser light used to form the holes 2 is, for example, light having an emission peak wavelength in the range of 255 nm to 10.6 μm. The spot diameter of the laser light is, for example, 3 μm to 200 μm.

[0151] The laser used to form the holes 2 is, for example, CO ２ It is a laser. ２ The wavelength of the laser is, for example, 10.6 μm. ２ The scanning speed of the laser is, for example, 100 mm / s or more and 400 mm / s or less, the frequency is, for example, 1 kHz or more and 30 kHz or less, and the output is, for example, 3.4 W or more and 100 W or less. ２ The holes 2 are formed by irradiating the laser in two passes or two steps at a scanning speed of 200 mm / s. The laser used to form the holes 2 may be an ultraviolet (UV) laser, a green laser, or the like. Alternatively, the holes 2 may be formed by dicing.

[0152] The holes 2 may be formed by a galvano laser irradiation device. The laser light source may be, for example, a CO ２ The galvanometer-type laser irradiation device has, for example, two galvanometer mirrors and a lens onto which light reflected by the galvanometer mirrors is incident. The two galvanometer mirrors include, for example, a galvanometer mirror that controls the reflected light in a first direction when the wavelength conversion member is viewed from above, and a galvanometer mirror that controls the reflected light in a second direction intersecting the first direction. The galvanometer-type laser irradiation device can irradiate laser light to any irradiation position by changing the angles of the two galvanometer mirrors, making it easier to perform fine processing other than linear processing (e.g., R processing) compared to, for example, a laser irradiation device that irradiates laser light while moving a nozzle.

[0153] When forming the holes 2 by laser processing, the holes 2 may be formed by irradiation in a single pass, or may be formed by irradiation in multiple passes or multiple steps.

[0154] Furthermore, when forming the hole 2 in multiple steps (e.g., two steps), for example, irradiation in the first step is performed at the irradiation position shown in FIG. 6A , and irradiation in the second step is performed at the irradiation position shown in FIG. 6B . The irradiation position in the second step is located outside the irradiation position in the first step. This allows the opening of the hole 2 to be wider than when irradiation is performed without moving the irradiation position between the first and second steps. Furthermore, the area of ​​the inner surface 2a of the hole 2 can be increased. Similarly, the opening and the area of ​​the inner surface 2a of the hole 2 can be increased by moving the irradiation position in the second step inward from the irradiation position in the first step. In the second step, the distance moved outward or inward from the irradiation position in the first step is, for example, equal to or less than the spot diameter of the laser light, preferably 3 μm to 200 μm, more preferably 100 μm to 150 μm. Note that in FIGS. 6B , 7 , and 8 , the irradiation light in the first step is exemplarily indicated by a dashed line, and the irradiation light in the second step is exemplarily indicated by a dashed line. In addition, in the description of the hole forming step, the terms "inside" and "outside" refer to the inside and outside of the wavelength conversion member to be manufactured.

[0155] By moving the irradiation position in this way to widen the opening of the hole 2, the material for the coating film 3 can be more easily placed in the hole 2 in the process of coating the inner surface of the hole with a coating film, as described below. Furthermore, when a resin is used as the material for the coating film 3 and the resin is applied to the hole 2, it is possible to prevent the resin that overflows from the hole 2 from accumulating on the upper surface of the laminate sheet 501. This allows a predetermined amount of resin to be supplied to be placed in the hole 2. Furthermore, when the laminate sheet 501 does not include the second protective sheet 552 or when the coating film 3 is formed after removing the second protective sheet 552, it is possible to prevent the resin from accumulating on the upper surface of the second barrier sheet 530, thereby smoothing the surface of the wavelength conversion member produced. Furthermore, by moving the irradiation position to widen the area of ​​the inner surface 2a of the hole 2, it is possible to increase the adhesion strength between the coating film 3 and the laminate sheet 501. As a result, a wavelength conversion member with high adhesion strength between the laminate 1 and the coating film 3 can be obtained. Furthermore, by moving the irradiation position in the second step outward from the irradiation position in the first step, the range of the inner laminate 1A can be widened in the manufactured wavelength conversion member.

[0156] 1F , a hole including a narrow portion and a wide portion can be formed by moving the irradiation position in the second step outward or inward from the irradiation position in the first step along the outer periphery of the wavelength conversion member to be manufactured, thereby increasing the area of ​​the opening and the inner surface of the hole.

[0157] Furthermore, when forming the hole 2 by laser processing, the irradiation position in the second step may be moved inward or outward from the irradiation position in the first step, and the irradiation intensity of the irradiation light in the first step may be made different from that of the irradiation light in the second step. For example, as shown in FIG. 7 , the irradiation position in the second step may be moved outward from the irradiation position in the first step, and the irradiation intensity of the irradiation light in the second step may be made weaker than that of the irradiation light in the first step. The irradiance intensity of the irradiation light in the second step may be, for example, an irradiation intensity that prevents the laser light from reaching the wavelength conversion sheet 520. The irradiance intensity of the irradiation light in the second step may be, for example, an irradiation intensity that removes at least a part of the second barrier sheet 530. This can increase the area of ​​the opening of the hole 2 and the area of ​​the inner surface 2 a of the hole 2. Furthermore, the area of ​​the wavelength conversion sheet 520 exposed from the second barrier sheet 530 can be narrowed. As a result, in the manufactured wavelength conversion member, the area of ​​the wavelength conversion layer 20 exposed from the second barrier layer 30 can be narrowed, and penetration of moisture, oxygen, etc. into the wavelength conversion layer 20 can be further suppressed.

[0158] Alternatively, the irradiation intensity of the irradiation light in the first step may be different from that in the second step, and the irradiation width of the irradiation light in the first step may be different from that in the second step. For example, as shown in FIG. 8 , the irradiation intensity of the irradiation light in the second step may be weaker than that in the first step, and the irradiation width of the irradiation light in the second step may be wider than that in the first step. The illuminance intensity of the irradiation light in the second step is, for example, an irradiation intensity that removes a part of the second barrier sheet 530 and does not reach the wavelength conversion sheet 520. The illuminance width of the irradiation light in the second step is, for example, 1.5 to 4 times the irradiation width of the irradiation light in the first step. This can increase the area of ​​the opening of the hole 2 and the area of ​​the inner surface 2 a of the hole 2. Furthermore, the area of ​​the wavelength conversion sheet 520 exposed from the second barrier sheet 530 can be narrowed.

[0159] 8 , the irradiation position in the second step may be moved inward or outward in a range in which the bottom surfaces of the holes formed in the second step overlap with the holes formed in the first step in top view. The irradiation position in the second step is, for example, inward or outward within a range of 50 μm to 200 μm from the irradiation position in the first step. This makes it possible to increase the areas of the openings of the holes 2 and the inner surfaces 2 a of the holes 2 and to narrow the area of ​​the wavelength-converting sheet 520 exposed from the second barrier sheet 530.

[0160] The number of steps in the laser processing is not limited to two, but may be three or more. Even when irradiating in three or more steps, the same effect as above can be obtained by appropriately moving the irradiation position, varying the irradiation intensity, and / or varying the irradiation width. Furthermore, the hole 2 may be formed by irradiation in one pass, or by irradiation in two or more passes.

[0161] Alternatively, the holes 2 may be formed by half-cutting the laminate sheet 501 using a cutter or the like. The cutter may be a Thomson blade, an ultrasonic cutter, or the like. The holes 2 may be formed, for example, by pressing the cutter into the laminate sheet 501 to compress the laminate sheet 501. Alternatively, the holes 2 may be formed by pressing a heated cutter into the laminate sheet 501 to thermally melt the laminate sheet 501. By thermally melting the laminate sheet 501, the inner surface 2a can be made smooth.

[0162] The holes 2 may also be formed by so-called precision half cutting. Specifically, the holes 2 may be formed by removing parts of the second protective sheet 552, the second barrier sheet 530, the wavelength conversion sheet 520, and the first barrier sheet 510 by precision half cutting.

[0163] Alternatively, the holes 2 may be formed by a blasting process using a mask, a dry etching process using plasma, or the like.

[0164] The step of forming the holes may further include a step of forming an uneven shape on the inner surface 2 a of the holes 2 after forming the holes 2. As such a step, for example, wet blasting or sand blasting can be used.

[0165] When the first barrier sheet 510 includes a main barrier sheet and an intermediate sheet, the hole 2 is formed, for example, across the second barrier sheet 530, the wavelength-converting sheet 520, and the intermediate sheet. That is, the part of the first barrier sheet 510 where the hole 2 is formed may be the intermediate sheet.

[0166] (1-3) Step of Coating the Inner Surface of the Hole with a Coating Film As shown in FIG. 5C , in this step, the inner surface 2a is coated with the coating film 3. At this time, the surface of the second protective sheet 552 may also be coated with the coating film 3. When a resin is used as the material for the coating film 3, the resin can be applied to the inner surface 2a and cured to form the coating film 3. For example, the resin is applied to the inner surface 2a by being placed in the hole 2 using an air dispenser. Dispensing methods such as a volumetric, screw, or jet dispenser may also be used. When forming the coating film 3 by applying the resin in this manner, the applied but uncured resin moves toward the bottom surface 2b due to gravity. As a result, for example, the coating film 3 covering the first side surface 24 can be made thicker than the coating film 3 covering the third side surface 34. This can further prevent moisture and other contaminants from entering the wavelength conversion layer 20. Note that by applying and curing the resin multiple times to form the coating film 3, the gravity can be utilized to make the coating film 3 on the first side surface 24 thicker.

[0167] 5D , in this step, the laminate sheet 501 is cut from the sixth main surface 532 toward the first main surface 511. In other words, the laminate sheet 501 is cut in the thickness direction Z. By this cutting, the first end surface 13 connected to the first main surface 511 is exposed, and a spare wavelength conversion member 505 including a hole 2 is formed.

[0168] In the spare wavelength conversion member 505, the hole 2 is located more inward than the first end face 13 at a cross section M1 that intersects with the third main surface 521 and passes through the first end face 13. At the cross section M1, the first side surface 24 included in the inner surface 2 a of the hole 2 is located in a range of 100 μm to 1000 μm from the first end face 13, for example.

[0169] Cutting of the laminate sheet 501 is performed by, for example, laser processing, cutting with a cutter, precision half-cutting, or the like, similar to the process of forming the holes 2. The laser light used to cut the laminate sheet 501 has an emission peak wavelength in the range of, for example, 255 nm to 10.6 μm. The spot diameter of the laser light is, for example, 3 μm to 200 μm.

[0170] The laser used to cut the laminate sheet 501 is, for example, a CO ２ It is a laser. ２ The wavelength of the laser is, for example, 10.6 μm. ２ The laser scanning speed is, for example, 50 mm / s or more and 400 mm / s or less, the frequency is, for example, 1 kHz or more and 30 kHz or less, and the output is, for example, 3.4 W or more and 100 W or less. ２ Cutting can be achieved by irradiating the laser with one pass at a scanning speed of 100 mm / s.

[0171] (1-5) Step of Obtaining a Wavelength Conversion Member from a Preliminary Wavelength Conversion Member As shown in FIG. 5E , in this step, the coating film 3 covering the surfaces of the first protective sheet 551 and the second protective sheet 552, and the second protective sheet 552 are removed to obtain a wavelength conversion member 100 including a laminate 1. The coating film 3 covering the surfaces of the first protective sheet 551 and the second protective sheet 552, and the second protective sheet 552 are removed by, for example, etching, plasma etching using a gas such as oxygen or fluorine, laser etching, or blast etching. Furthermore, at this stage, a buffer material may be placed in the hole 2. The step of placing a buffer material may be performed at any time after the step (1-3) of coating the inner surface of the hole with a coating film.

[0172] The above describes a case where the step (1-4) of forming a spare wavelength conversion member is performed after the step (1-3) of coating the inner surface of the hole with a coating film. The step (1-4) of forming a spare wavelength conversion member may be performed between the step (1-2) of forming a hole and the step (1-3) of coating the inner surface of the hole with a coating film. When the step (1-4) of forming a spare wavelength conversion member is performed after the step (1-2) of forming a hole, two cutting steps, a half-cutting step and a full-cutting step, can be performed consecutively on the wavelength conversion member. This allows the two cutting steps to be performed in the same cutting device, thereby shortening the time required for the cutting steps. The step (1-3) of coating the inner surface of the hole with a coating film may be performed after removing the second protective sheet 552 from the spare wavelength conversion member.

[0173] 6. Manufacturing Method 2 The manufacturing method (manufacturing method 2) of the wavelength conversion member 200 according to embodiment 2 differs from manufacturing method 1 in the location at which the laminate sheet 501 is cut in the step of forming a preliminary wavelength conversion member including holes. Furthermore, in manufacturing method 2, the direction in which the holes 2 are formed in the step of forming the holes may differ from manufacturing method 1. Furthermore, manufacturing method 2 may differ from manufacturing method 1 in that, in the step of covering the inner surfaces of the holes with a coating film, after the coating film 3 is formed, part of the coating film 3 is removed.

[0174] The differences from Manufacturing Method 1 are explained in detail below. Note that the same content as in Manufacturing Method 1 is omitted. Specifically, the (2-1) step of preparing a laminate sheet and the (2-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 2 are the same as the (1-1) step of preparing a laminate sheet and the (1-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 1, respectively, and therefore will be omitted below.

[0175] 9A , the hole 202 is formed in the second protective sheet 552, the second barrier sheet 530, the wavelength conversion sheet 520, and a part of the first barrier sheet 510 in a direction intersecting with the thickness direction Z. Specifically, the third side surface 234, the first side surface 224, and the second side surface 214 constituting the hole 202 are inclined in this order from the inside toward the outside of the wavelength conversion member 200 to be manufactured. In other words, the inner surface 202a of the formed hole 202 includes the second side surface 214, the first side surface 224, and the third side surface 234 that intersect with the thickness direction Z.

[0176] The step of forming the holes may further include a step of forming an uneven shape on the inner surface 202a of the holes 202 after the holes 202 are formed. For example, wet blasting or sand blasting can be used as such a step. The same applies to the manufacturing methods according to the other embodiments described below.

[0177] (2-3) Step of Coating Inner Surface of Hole with Coating Film After forming the hole 202, the inner surface 202a of the hole 202 is coated with the coating film 3 by the same method as in manufacturing method 1. At this time, the surface of the second protective sheet 552 may also be coated with the coating film 3.

[0178] 9B , a portion of the coating film 3 on the bottom surface 2 b of the hole 202 is removed to expose the first barrier sheet 510. This removal is performed by, for example, etching, plasma etching using a gas such as oxygen or fluorine, laser etching, or blast etching. At this time, a portion of the first barrier sheet 510 may also be removed to expose the first barrier sheet 510. By removing this portion, a step 17 can be formed.

[0179] 9C , in manufacturing method 2, the laminate sheet 501 is cut from the bottom surface 2 b of the hole 202 toward the first main surface 511. For example, the laminate sheet 501 is cut in the thickness direction Z at the bottom of the step portion 17. By this cutting, the first end surface 13 connected to the first main surface 511 is exposed.

[0180] Thereafter, the first protective sheet 551, the second protective sheet 552, and the coating film 3 covering the surface of the second protective sheet 552 are removed. As a result, as shown in Fig. 9D , the wavelength conversion member 200 can be obtained in which the third side surface 234, the first side surface 224, and the second side surface 214 are located more inward than the first end surface 13 at a cross section M1 that intersects with the third main surface 21 of the wavelength conversion layer 220 and passes through the first end surface 13.

[0181] 7. Manufacturing Method 3 The manufacturing method (manufacturing method 3) of wavelength conversion member 300 according to embodiment 3 differs from manufacturing method 1 in that, in the step of coating the inner surfaces of the holes with a coating film, holes 2 are filled with coating film 3 to cover inner surfaces 2 a, and sixth main surface 532 is also coated with coating film 3. Furthermore, manufacturing method 3 differs from manufacturing method 1 in that it includes a step of arranging a third barrier sheet before the step of obtaining a preliminary wavelength conversion member including holes.

[0182] The differences from Manufacturing Method 1 are explained in detail below. Note that the same content as in Manufacturing Method 1 is omitted. Specifically, the (3-2) step of forming holes and the (3-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 3 are the same as the (1-2) step of forming holes and the (1-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 1, respectively, and therefore will be omitted below.

[0183] (3-1) Step of Preparing Laminate Sheet As shown in Fig. 10A , a laminate sheet 501A in production method 3 includes a first protective sheet 551, a first barrier sheet 510, a wavelength conversion sheet 520, and a second barrier sheet 530. In the laminate sheet 501A shown in Fig. 10A , the second protective sheet is removed after the step of (3-2) forming holes.

[0184] 10A , in manufacturing method 3, hole 2 is filled with coating film 3 to coat inner surface 2a, and sixth main surface 532 is also coated with coating film 3. The method of forming coating film 3 can be the same as manufacturing method 1.

[0185] 10B , in this step, the third barrier sheet 540 is placed on the coating film 3 that covers the sixth main surface 532. The third barrier sheet 540 can be placed on the coating film 3, using the coating film 3 that covers the sixth main surface 532 as an adhesive member.

[0186] (3-4) Step of forming a spare wavelength conversion member including holes In the step of forming a spare wavelength conversion member including holes, the coating film 3 that covers the third barrier sheet 540 and the sixth main surface 532 together with the laminate sheet 501A is cut to expose the first end surface.

[0187] 8. Manufacturing Method 4 The manufacturing method of wavelength conversion member 400 according to embodiment 4 (Manufacturing Method 4) differs from Manufacturing Method 1 in that, in the step of preparing a laminate sheet, a laminate sheet is prepared that does not include a second barrier sheet 530. Manufacturing Method 4 also differs from Manufacturing Method 1 in that, in the step of coating the inner surfaces 2a of the holes with a coating film, the holes 2 are filled with a coating film 3 to cover the inner surfaces, and the fourth main surface 522 is also coated with the coating film 3. Manufacturing Method 4 also differs from Manufacturing Method 1 in that it includes a step of arranging a second barrier sheet before the step of obtaining a preliminary wavelength conversion member including holes.

[0188] The differences from Manufacturing Method 1 are explained in detail below. Note that the same content as in Manufacturing Method 1 is omitted. Specifically, the (4-2) step of forming holes and the (4-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 4 are the same as the (1-2) step of forming holes and the (1-5) step of obtaining a wavelength conversion member from a spare wavelength conversion member in Manufacturing Method 1, respectively, and therefore will be omitted below.

[0189] (4-1) Step of Preparing Laminate Sheet As shown in Fig. 11A , a laminate sheet 501B in production method 4 includes a first protective sheet 551, a first barrier sheet 510, and a wavelength conversion sheet 520. In the laminate sheet 501B shown in Fig. 11A , the second protective sheet is removed after the step of (4-2) forming holes.

[0190] 11A , in manufacturing method 4, hole 2 is filled with coating film 3 to coat inner surface 2a, and fourth main surface 522 is also coated with coating film 3. The method for forming coating film 3 can be the same as that of manufacturing method 1.

[0191] 11B , in this step, the second barrier sheet 530 is placed on the coating film 3 that covers the fourth main surface 522. The second barrier sheet 530 can be placed on the coating film 3, using the coating film 3 that covers the fourth main surface 522 as an adhesive member.

[0192] (4-4) Step of forming a spare wavelength conversion member including holes In the step of forming a spare wavelength conversion member including holes, the coating film 3 that covers the second barrier sheet 530 and the fourth main surface 522 together with the laminate sheet 501B is cut to expose the first end surface.

[0193] 9. Other Configurations Furthermore, for example, the present disclosure can have the following configurations: Clause (1) A wavelength conversion member comprising: a laminate including: a first barrier layer including a first main surface, a second main surface opposite the first main surface, and an end surface connected to the first main surface; a wavelength conversion layer including a third main surface and a fourth main surface opposite the third main surface, the wavelength conversion layer including quantum dots being disposed on the first barrier layer with the third main surface facing the second main surface of the first barrier layer; and a second barrier layer including a fifth main surface and a sixth main surface opposite the fifth main surface, the second barrier layer being disposed on the wavelength conversion layer with the fifth main surface facing the fourth main surface of the wavelength conversion layer; wherein the wavelength conversion layer has a first side surface that is located inside the end surface in a cross section that intersects the third main surface and passes through the end surface, and that connects the third main surface and the fourth main surface, and the first side surface is covered with a coating film.

[0194] Item (2) The wavelength conversion member according to Item 1, wherein the first barrier layer is located more inward than the end face in the cross section and has a second side surface connected to the second main surface, the laminate is provided across the wavelength conversion layer and a part of the first barrier layer, and has a hole having an inner surface including the first side surface and the second side surface, and the coating film continuously covers the first side surface and the second side surface within the hole.

[0195] Item (3) The wavelength conversion member according to Item 2, wherein the second barrier layer has a third side surface that connects the fifth main surface and the sixth main surface and is located inward from the end surface in the cross section, the hole is provided further across the second barrier layer and has the inner surface that further includes the third side surface, and the coating film further continuously covers the first side surface and the third side surface within the hole.

[0196] Item (4) The wavelength conversion member according to Item 2 or 3, wherein a buffer material is further disposed in the hole.

[0197] Item (5) The wavelength conversion member according to Item 2 or 3, wherein the coating film is disposed to fill the holes and further covers the sixth main surface, and further includes a third barrier layer stacked on the sixth main surface via the coating film.

[0198] Item (6) The wavelength conversion member according to Item 2, wherein the coating film is disposed to fill the holes and further covers the fourth main surface, and the second barrier layer is stacked on the fourth main surface via the coating film.

[0199] Item (7) The wavelength conversion member according to Item 1, wherein the first barrier layer is located more inward than the end face in the cross section and has a second side surface connected to the second main surface, the second barrier layer is located more inward than the end face in the cross section and has a third side surface connecting the fifth main surface and the sixth main surface, and the coating film continuously covers the first side surface, the second side surface, and the third side surface, and is exposed on an outer peripheral surface of the laminate.

[0200] Item (8) The wavelength conversion member according to any one of Items 2 to 7, wherein the first barrier layer includes a main barrier layer and an intermediate layer stacked between the main barrier layer and the wavelength conversion layer and having the second side surface.

[0201] Item (9) The wavelength conversion member according to any one of items 1 to 8, wherein the first side surface is arranged along an outer periphery of the laminate.

[0202] Item (10) The wavelength conversion member according to any one of Items 1 to 9, wherein the first side surface is located in a range of 100 μm to 1000 μm from the end surface in the cross section.

[0203] Item (11) The wavelength conversion member according to any one of Items 1 to 10, wherein the coating film includes: a first layer made of at least one selected from the group consisting of a thermosetting urethane resin, a phenolic resin, a urea melamine resin, an epoxy resin, an unsaturated polyester resin, and a silicone resin; and a second layer made of at least one selected from the group consisting of a vinylidene chloride resin, a fluorine-based resin, and an oxide, and disposed on the first layer.

[0204] Item (12) The wavelength conversion member according to any one of Items 1 to 10, wherein the coating film includes a plating layer and an atomic layer deposition layer disposed on the plating layer.

[0205] Item (13) The wavelength conversion member according to any one of Items 1 to 10, wherein the coating film includes an oxygen plasma-treated layer and a chemical vapor deposition layer disposed on the oxygen plasma-treated layer.

[0206] Item (14) A method for manufacturing a laminate sheet comprising: preparing a laminate sheet comprising: a first barrier sheet including a first main surface and a second main surface located opposite to the first main surface; a wavelength conversion sheet including a third main surface and a fourth main surface located opposite to the third main surface, the wavelength conversion sheet including quantum dots, and disposed on the first barrier sheet such that the third main surface faces the second main surface of the first barrier sheet; and a second barrier sheet including a fifth main surface and a sixth main surface located opposite to the fifth main surface, the wavelength conversion sheet being disposed on the wavelength conversion sheet such that the fifth main surface faces the fourth main surface of the wavelength conversion sheet; forming a hole extending through the second barrier sheet, the wavelength conversion sheet, and a part of the first barrier sheet, the hole having an inner surface including a third side surface connecting the fifth main surface and the sixth main surface, a first side surface connecting the third main surface and the fourth main surface, and a second side surface connecting to the second main surface; coating the inner surface of the hole with a coating film; cutting the laminate sheet from the sixth main surface toward the first main surface to expose an end face connected to the first main surface, and forming a spare wavelength conversion member including the hole, wherein the spare wavelength conversion member has the hole positioned more inward than the end face in a cross section that intersects the third main surface and passes through the end face.

[0207] Item (15) The method for manufacturing a wavelength conversion member according to Item 14, wherein the first barrier sheet includes a main barrier sheet and an intermediate sheet laminated between the main barrier sheet and the wavelength conversion sheet, and a part of the first barrier sheet in which the hole is formed is the intermediate sheet.

[0208] Item (16) The method for producing a wavelength conversion member according to Item 14 or 15, further comprising placing a buffer material in the hole.

[0209] Item (17) The method for manufacturing a wavelength conversion member according to any one of Items 14 to 16, wherein in the cross section, the first side surface is located in a range of 100 μm to 1000 μm from the end surface.

[0210] Item (18) A method for manufacturing a laminate sheet comprising: preparing a laminate sheet comprising: a first barrier sheet including a first main surface and a second main surface located opposite to the first main surface; a wavelength conversion sheet including a third main surface and a fourth main surface located opposite to the third main surface, the wavelength conversion sheet including quantum dots, and disposed on the first barrier sheet such that the third main surface faces the second main surface of the first barrier sheet; and a second barrier sheet including a fifth main surface and a sixth main surface located opposite to the fifth main surface, the wavelength conversion sheet being disposed on the wavelength conversion sheet such that the fifth main surface faces the fourth main surface of the wavelength conversion sheet; forming a hole extending through the second barrier sheet, the wavelength conversion sheet, and a part of the first barrier sheet, the hole having an inner surface including a third side surface connecting the fifth main surface and the sixth main surface, a first side surface connecting the third main surface and the fourth main surface, a second side surface connecting to the second main surface, and a bottom surface made of the first barrier sheet; coating the inner surface of the hole with a coating film; cutting the laminate sheet from the bottom surface toward the first main surface to expose an end surface connected to the first main surface, and forming a spare wavelength conversion member including the third side surface, the first side surface, and the second side surface, wherein the spare wavelength conversion member has the third side surface, the first side surface, and the second side surface positioned more inward than the end surface in a cross section that intersects the third main surface and passes through the end surface.

[0211] Item (19) The method for manufacturing a wavelength conversion member according to Item 18, wherein the first barrier sheet includes a main barrier sheet and an intermediate sheet laminated between the main barrier sheet and the wavelength conversion sheet, and a part of the first barrier sheet in which the hole is formed is the intermediate sheet.

[0212] Item (20) The method for manufacturing a wavelength conversion member according to Item 18 or 19, further comprising removing a part of the coating film to expose the first barrier sheet, wherein the spare wavelength conversion member includes the exposed bottom surface connected to the end surface.

[0213] Item (21) The method for producing a wavelength conversion member according to any one of Items 14 to 20, wherein forming the holes and cutting the laminate sheet are performed by laser processing.

[0214] Item (22) The method for manufacturing a wavelength conversion member according to any one of Items 14 to 21, wherein the holes are arranged along an outer periphery of the spare wavelength conversion member.

[0215] Item (23) The method for producing a wavelength conversion member according to any one of Items 14 to 22, wherein the coating film includes: a first layer made of at least one selected from the group consisting of a thermosetting urethane resin, a phenolic resin, a urea melamine resin, an epoxy resin, an unsaturated polyester resin, and a silicone resin; and a second layer made of at least one selected from the group consisting of a vinylidene chloride resin, a fluorine-based resin, and an oxide, and disposed on the first layer.

[0216] Item (24) The method for producing a wavelength conversion member according to any one of Items 14 to 22, wherein the coating film includes a plating layer and an atomic layer deposition layer disposed on the plating layer.

[0217] Item (25) The method for producing a wavelength conversion member according to any one of Items 14 to 22, wherein the coating film includes an oxygen plasma-treated layer and a chemical vapor deposition layer disposed on the oxygen plasma-treated layer.

[0218] Item (26) The method for producing a wavelength conversion member according to any one of Items 14 to 25, wherein forming the spare wavelength conversion member is performed after covering with the covering film.

[0219] Item (27) The method for producing a wavelength conversion member according to any one of Items 14 to 25, wherein the coating with the coating film is performed after the formation of the spare wavelength conversion member.

[0220] The above describes embodiments and modifications of the present disclosure, but the disclosed contents may vary in details of the configuration, and combinations and changes in the order of elements in the embodiments and modifications may be realized without departing from the scope and spirit of the claimed disclosure.

[0221] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0222] Reference Example 1: Fabrication of Laminated Sheet Preparation of Dispersion Containing Semiconductor Nanoparticles First, as dispersions containing semiconductor nanoparticles, Dispersion A containing InP that emits green light and Dispersion B containing InP that emits red light were prepared. The content of semiconductor nanoparticles in Dispersion A was 10% by mass. The content of semiconductor nanoparticles in Dispersion B was 10% by mass. The dispersion medium for Dispersions A and B was isobornyl acrylate (IBOA).

[0223] Emission Characteristics The emission characteristics were measured for Dispersion A containing InP that emits green light and Dispersion B containing InP that emits red light. Using a quantum efficiency measurement device (QE-2100), light having an emission peak wavelength of 450 nm was irradiated onto Dispersion A containing InP that emits green light and Dispersion B containing InP that emits red light, and the emission spectra were measured at room temperature (25°C). Dispersion A containing InP that emits green light and Dispersion B containing InP that emits red light were diluted with chloroform to an absorbance of 0.15 at 450 nm before use. From the obtained emission spectra, Dispersion A containing InP that emits green light had an internal quantum efficiency of 80%, an emission peak wavelength of 532 nm, and a half-width of the emission spectrum of 35 nm. From the obtained emission spectrum, Dispersion B containing InP that emits red light had an internal quantum efficiency of 79%, an emission peak wavelength of 628 nm, and a half-width of the emission spectrum of 34 nm. The internal quantum efficiency (%) is the ratio of photons converted into light to photons absorbed by the nanoparticles, and was calculated by dividing the number of emitted photons (%) by the number of absorbed photons (%). The luminescence characteristics of Dispersion A containing InP that emits green light and Dispersion B containing InP that emits red light are shown in Table 1.

[0224]

[0225] Dispersion A containing InP that emits green light had an internal quantum efficiency of 80% and a half-width of 35 nm. It also had an emission peak wavelength of 532 nm and emitted green light by absorbing light with a peak emission wavelength of 450 nm. Dispersion B containing InP that emits red light had an internal quantum efficiency of 79% and a half-width of 34 nm. It also had an emission peak wavelength of 628 nm and emitted red light by absorbing light with a peak emission wavelength of 450 nm.

[0226] 10 g of 2,2-bis[[(3-mercaptopropionyl)oxy]methyl]trimethylene bis[3-mercaptopropionate] (PEMP) and 0.33 g of 2,4,6-trimethylbenzoylphosphine oxide (TPO), a photopolymerization initiator, were stirred in a brown bottle for 24 hours to obtain a PEMP / TPO solution.

[0227] Photocurable composition A was prepared by mixing 0.9 g of the PEMP / TPO solution, 2.1 g of tricyclodecane dimethanol diacrylate (A-DCP; manufactured by Shin-Nakamura Chemical Co., Ltd.), 0.09 g of silicone particles (KMP-706; manufactured by Shin-Etsu Chemical Co., Ltd.), and 0.3 g of dispersion A containing green-emitting InP in a planetary centrifugal mixer.

[0228] Similarly, 1.4 g of the PEMP / TPO solution, 3.5 g of tricyclodecane dimethanol diacrylate (A-DCP; manufactured by Shin-Nakamura Chemical Co., Ltd.), 0.5 g of silicone particles (KMP-706; manufactured by Shin-Etsu Chemical Co., Ltd.), and 0.15 g of dispersion B containing red-emitting InP were mixed in a planetary centrifugal mixer to prepare photocurable composition B.

[0229] A barrier film (TBF1004; manufactured by i-components) was prepared as the barrier layer. A PET film was also prepared as the release substrate. The PET film was prepared on one side and the barrier film on the other side, and photocurable composition B was applied between the two films. After that, a roll-to-roll coater was used to apply 120 mJ / cm from a UV irradiator. ２to initiate a polymerization reaction of the monomer, thereby pre-curing the monomer, and thereby preparing a laminated sheet 1 having a wavelength conversion layer 1 with a thickness of 50 μm, on one side of which a barrier film was adhered and on the other side of which a PET film was adhered.

[0230] The PET film of the laminated sheet 1 was peeled off, and photocurable composition A was applied between the barrier film and the wavelength-converting layer 1. Then, a roll-to-roll coater was used to apply 6060 mJ / cm from a UV irradiator. ２ to initiate a polymerization reaction of the monomers and cure them, thereby producing a laminate sheet 2 in which a barrier film was bonded to the main surfaces of the wavelength-converting layer 1 having a thickness of 50 μm and the wavelength-converting layer 2 having a thickness of 50 μm.

[0231] Example 1 The wavelength conversion member of Example 1 was produced as follows. A hole was formed in the obtained laminate sheet, penetrating the barrier layer and the wavelength conversion layer and reaching the other barrier layer, on the inner side of the end face of the laminate sheet. Specifically, as an example, CO 2 was added so that the distance from the end face of the laminate sheet to the inner surface of the hole was 500 μm or less. ２ The laminate was half-cut using a laser. The hole had a center 350 μm from the edge of the laminate sheet and a width of 300 μm. The half-cutting conditions were, for example, CO 2 laser with a wavelength of 10.6 μm. ２ Using a laser, the first half cut (first step) was performed under conditions of a scanning speed of 400 mm / s, two passes, a frequency of 5 kHz, and an output of 30 W, and then a second half cut (second step) was performed under the same conditions at a position adjacent to the irradiation position of the first step.

[0232] Next, 3017B (manufactured by Three Bond Co.) was filled into the holes formed by half-cutting using an air dispenser as a coating film, and 6000 mJ / cm was applied from a UV irradiator, for example. ２ The wavelength conversion member of Example 1 was prepared by irradiating the composition with ultraviolet light having an integrated light amount of 10 ...

[0233] Example 2 A wavelength conversion member of Example 2 was produced in the same manner as in Example 1, except that the type of coating film was changed to TB3715 (manufactured by Three Bond Corporation).

[0234] Example 3 A wavelength conversion member of Example 3 was produced in the same manner as in Example 1, except that the type of coating film was changed to XS-LMP1100 (manufactured by Kyoritsu Chemical Co., Ltd.).

[0235] Comparative Example 1 A wavelength conversion member of Comparative Example 1 was produced in the same manner as in Example 1, except that no coating film was placed on the holes.

[0236] The wavelength conversion members obtained above were evaluated for color fading from the edges as follows. Each wavelength conversion member was placed in a thermo-hygrostat (manufactured by Espec Corporation) in an atmosphere of a temperature of 85°C and a relative humidity of 85%. After 500 hours, the member was removed from the thermo-hygrostat and used as a sample after the storage test.

[0237] For the samples after the storage test, the appearance was photographed from the main surface side using a digital camera (manufactured by Olympus) to obtain an evaluation image. Using image analysis software for the evaluation image, an emission intensity profile corresponding to green was obtained, with the horizontal axis representing the distance from one side of the wavelength conversion member to the opposite side. In the obtained emission intensity profile, the emission intensity at the midpoint equidistant from both ends of the wavelength conversion member and the emission intensity at two points 0.5 mm from the midpoint, a total of three emission intensities, were calculated as 100% to obtain a relative emission intensity profile. The distance (mm) from the inner surface of the hole corresponding to a relative emission intensity of 85% in the relative emission intensity profile was determined and used as an evaluation value for discoloration. The results are shown in Table 2.

[0238]

[0239] The disclosures of Japanese Patent Application No. 2022-110496 (filing date: July 8, 2022), Japanese Patent Application No. 2022-192772 (filing date: December 1, 2022), and Japanese Patent Application No. 2023-037777 (filing date: March 10, 2023) are incorporated herein by reference in their entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A first barrier layer comprising a first main surface, a second main surface located opposite the first main surface, and an end surface connected to the first main surface, A wavelength conversion layer including quantum dots, comprising a third principal surface and a fourth principal surface located opposite the third principal surface, wherein the third principal surface and the second principal surface of the first barrier layer face each other and are arranged on the first barrier layer, A second barrier layer is disposed on the wavelength conversion layer, including a fifth main surface and a sixth main surface located opposite the fifth main surface, wherein the fifth main surface and the fourth main surface of the wavelength conversion layer face each other. A laminate comprising, The wavelength conversion layer has a first surface that is located inside the end face and connects the third main surface and the fourth main surface in a cross-section that intersects the third main surface and passes through the end face, The first side surface is a wavelength conversion member covered with a coating film.

2. The first barrier layer has a second side surface located inward from the end face in the cross-section and connected to the second main surface, The laminate is provided with a hole extending from the wavelength conversion layer to a part of the first barrier layer, and having an inner surface including the first side surface and the second side surface. The wavelength conversion member according to claim 1, wherein the coating film continuously covers the first side surface and the second side surface within the pore.

3. The second barrier layer has a third surface in the cross-section that connects the fifth main surface and the sixth main surface and is located inside the end surface. The hole is provided further in the second barrier layer and has the inner surface which further includes the third side surface, The wavelength conversion member according to claim 2, wherein the coating film further continuously covers the first side surface and the third side surface within the pore.

4. The wavelength conversion member according to claim 3, wherein a buffer material is further disposed in the hole.

5. The coating film is positioned to fill the holes and further covers the sixth main surface. The wavelength conversion member according to claim 2, further comprising a third barrier layer laminated on the sixth main surface via the coating film.

6. The coating film is positioned to fill the holes and further covers the fourth main surface. The wavelength conversion member according to claim 2, wherein the second barrier layer is laminated on the fourth main surface via the coating film.

7. The first barrier layer has a second side surface located inward from the end face in the cross-section and connected to the second main surface, The second barrier layer is located inward from the end face in the cross-section and has a third surface that connects the fifth main surface and the sixth main surface. The aforementioned coating film is The first side, the second side, and the third side are covered in a continuous manner. The wavelength conversion member according to claim 1, which is exposed on the outer surface of the laminate.

8. The wavelength conversion member according to any one of claims 2 to 7, wherein the first barrier layer includes a main barrier layer and an intermediate layer laminated between the main barrier layer and the wavelength conversion layer and having the second side surface.

9. The wavelength conversion member according to any one of claims 1 to 7, wherein the first side surface is arranged along the outer circumference of the laminate.

10. The wavelength conversion member according to any one of claims 1 to 7, wherein the first side surface is located in the cross-section within a range of 100 μm or more and 1000 μm or less from the end face.

11. The aforementioned coating film is A first layer comprising at least one selected from the group consisting of thermosetting urethane resin, phenolic resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin, A second layer, which is disposed on the first layer, consists of at least one selected from the group consisting of vinylidene chloride resin, fluororesin, and oxide, A wavelength conversion member according to any one of claims 1 to 7, including the wavelength conversion member described in any one of claims 1 to 7.

12. The wavelength conversion member according to any one of claims 1 to 7, wherein the coating film comprises a plating layer and an atomic layer deposition layer disposed on the plating layer.

13. The wavelength conversion member according to any one of claims 1 to 7, wherein the coating film comprises an oxygen plasma treated layer and a chemical vapor deposition layer disposed on the oxygen plasma treated layer.

14. A first barrier sheet comprising a first main surface and a second main surface located opposite the first main surface, A wavelength conversion sheet including quantum dots, comprising a third principal surface and a fourth principal surface located opposite the third principal surface, wherein the third principal surface and the second principal surface of the first barrier sheet face each other and are arranged on the first barrier sheet, A second barrier sheet is disposed on the wavelength conversion sheet with the fifth main surface and the fourth main surface of the wavelength conversion sheet facing each other, and the second barrier sheet includes a fifth main surface and a sixth main surface located opposite the fifth main surface, Prepare a laminated sheet containing, A hole is formed that extends across the second barrier sheet, the wavelength conversion sheet, and a portion of the first barrier sheet, and has an inner surface including a third surface connecting the fifth main surface and the sixth main surface, a first surface connecting the third main surface and the fourth main surface, and a second surface connecting to the second main surface. The inner surface of the aforementioned hole is covered with a coating film, The laminated sheet is cut from the sixth main surface toward the first main surface, the end face connected to the first main surface is exposed, and a pre-wavelength conversion member including the hole is formed. Includes, A method for manufacturing a wavelength conversion member, wherein the pre-wavelength conversion member has a cross-section in which the hole is located inside the end face, intersecting the third main surface and passing through the end face.

15. The first barrier sheet includes a main barrier sheet and an intermediate sheet laminated between the main barrier sheet and the wavelength conversion sheet. The method for manufacturing a wavelength conversion member according to claim 14, wherein a part of the first barrier sheet in which the holes are formed is the intermediate sheet.

16. The method for manufacturing a wavelength conversion member according to claim 14, further comprising arranging a buffer material in the aforementioned holes.

17. The method for manufacturing a wavelength conversion member according to claim 14, wherein in the cross-section, the first side surface is located in a range of 100 μm or more and 1000 μm or less from the end face.

18. A first barrier sheet comprising a first main surface and a second main surface located opposite the first main surface, A wavelength conversion sheet including quantum dots, comprising a third principal surface and a fourth principal surface located opposite the third principal surface, wherein the third principal surface and the second principal surface of the first barrier sheet face each other and are arranged on the first barrier sheet, A second barrier sheet is disposed on the wavelength conversion sheet with the fifth main surface and the fourth main surface of the wavelength conversion sheet facing each other, and the second barrier sheet includes a fifth main surface and a sixth main surface located opposite the fifth main surface, Prepare a laminated sheet containing, A hole is formed that extends across the second barrier sheet, the wavelength conversion sheet, and a portion of the first barrier sheet, and has an inner surface including a third side surface connecting the fifth main surface and the sixth main surface, a first side surface connecting the third main surface and the fourth main surface, a second side surface connected to the second main surface, and a bottom surface made of the first barrier sheet. The inner surface of the aforementioned hole is covered with a coating film, The laminated sheet is cut from the bottom surface toward the first main surface, the end surface connected to the first main surface is exposed, and a pre-wavelength conversion member including the third side surface, the first side surface, and the second side surface is formed. Includes, A method for manufacturing a wavelength conversion member, wherein the pre-wavelength conversion member is such that, in a cross-section intersecting the third main surface and passing through the end face, the third side surface, the first side surface, and the second side surface are located inward from the end face.

19. The first barrier sheet includes a main barrier sheet and an intermediate sheet laminated between the main barrier sheet and the wavelength conversion sheet. The method for manufacturing a wavelength conversion member according to claim 18, wherein a part of the first barrier sheet in which the holes are formed is the intermediate sheet.

20. The method further includes removing a portion of the coating film to expose the first barrier sheet, The method for manufacturing a wavelength conversion member according to claim 18, wherein the pre-wavelength conversion member includes the exposed bottom surface connected to the end surface.

21. A method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein the formation of the holes and the cutting of the laminated sheet are performed by laser processing.

22. The method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein the holes are arranged along the outer circumference of the pre-wavelength conversion member.

23. The aforementioned coating film is A first layer comprising at least one selected from the group consisting of thermosetting urethane resin, phenolic resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin, A second layer is disposed on the first layer and consists of at least one selected from the group consisting of vinylidene chloride resin, fluororesin, and oxide, A method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, including the method described above.

24. The method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein the coating film comprises a plating layer and an atomic layer deposition layer disposed on the plating layer.

25. The method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein the coating film comprises an oxygen plasma treated layer and a chemical vapor deposition layer disposed on the oxygen plasma treated layer.

26. The method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein forming the pre-wavelength conversion member is performed after coating with the coating film.

27. The method for manufacturing a wavelength conversion member according to any one of claims 14 to 20, wherein coating with the coating film is performed after forming the pre-wavelength conversion member.