TW202113028A - Wavelength conversion member, method of producing wavelength conversion member, laminate, backlight unit, and image display device - Google Patents

Abstract

A wavelength conversion member, comprising a wavelength conversion layer that includes a phosphor and a cured resin, and covering members that are disposed on each side of the wavelength conversion layer, wherein the wavelength conversion member is in a state of having, on an outer surface of at least one of the covering members, a carrier film that is capable of being removed from the covering material.

Description

Wavelength conversion material, manufacturing method of wavelength conversion material, laminate, backlight unit and image display device

The present disclosure relates to a wavelength conversion material, a manufacturing method of the wavelength conversion material, a laminate, a backlight unit, and an image display device.

In recent years, in the field of image display devices such as liquid crystal display devices, it has been required to improve the color reproducibility of displays as a means to improve color reproducibility. For example, Japanese Patent Publication No. 2013-544018 and International Publication No. 2016/ A wavelength conversion material containing a phosphor as described in No. 052625 has attracted attention.

The wavelength conversion material containing the phosphor is arranged in, for example, a backlight unit of an image display device. In the case of using a wavelength conversion material including a phosphor that emits red light and a phosphor that emits green light, if the wavelength conversion material is irradiated with blue light as the excitation light, the red light emitted from the phosphor can be used White light is obtained by light, green light, and blue light passing through the wavelength conversion material. Through the development of wavelength conversion materials containing phosphors, the color reproducibility of the display has been expanded from the previous 72% NTSC ((United States) National Television System Committee (National Television System Committee)) ratio to 100% NTSC ratio.

[The problem to be solved by the invention] The main application of wavelength conversion materials so far has been relatively large displays such as televisions, but the demand for small displays such as smart phones and input boards is expected to increase in the future. Therefore, it is considered to advance the thickness reduction (for example, the thickness of 150 μm or less) for making wavelength conversion materials compatible with small displays.

The wavelength conversion material generally includes a wavelength conversion layer including a phosphor and a coating material arranged on both sides of the wavelength conversion layer. The wavelength conversion layer is formed by curing a resin composition including the phosphor. Therefore, if the thickness of the wavelength conversion material is reduced, the rigidity is reduced, wrinkles accompanying the curing shrinkage of the resin composition are likely to occur, and the appearance may be damaged.

In view of the above-mentioned circumstances, the subject of the present disclosure is to provide a wavelength conversion material and a manufacturing method thereof that suppress the generation of wrinkles even if the thickness is thin. In addition, the subject of the present disclosure is to provide a laminate for manufacturing the wavelength conversion material, and a backlight unit and an image display device using the wavelength conversion material. [Means to solve the problem]

The means for solving the above-mentioned problems include the following aspects. <1> A wavelength conversion material, comprising: a wavelength conversion layer including a phosphor and a hardened resin; and a coating material arranged on both sides of the wavelength conversion layer, the wavelength conversion material being in the coating The outer surface of at least one of the materials is in a state where a carrier film that can be peeled from the covering material is arranged. <2> The wavelength conversion material according to <1>, wherein the ratio of the thickness A of the carrier film to the thickness B of the wavelength conversion layer is 0.4 or more. <3> The wavelength conversion material according to <1> or <2>, wherein the Tg of the carrier film is 50°C or higher. <4> The wavelength conversion material according to any one of <1> to <3>, wherein the carrier film has a peeling force from the covering material measured under the condition of a peeling speed of 300 mm/min. 0.7 N/25 mm or less. <5> The wavelength conversion material according to any one of <1> to <4>, wherein the thickness of the coating material is 25 μm or less. <6> The wavelength conversion material according to any one of <1> to <5>, wherein the thickness of the wavelength conversion material in a state where the carrier film is not arranged is 150 μm or less. <7> The wavelength conversion material according to any one of <1> to <6>, wherein the thickness of the carrier film is 30 μm to 200 μm. <8> The wavelength conversion material according to any one of <1> to <7>, wherein the wrinkle height in a state where the carrier film is not arranged is less than 3.0 mm. <9> A wavelength conversion material, comprising: a wavelength conversion layer including a phosphor and a cured resin; and a coating material, arranged on both sides of the wavelength conversion layer, the wavelength conversion layer and the coating material The total thickness is 150 μm or less. <10> The wavelength conversion material according to <9>, wherein the wrinkle height is less than 3.0 mm. <11> The wavelength conversion material according to any one of <1> to <10>, which is in the form of a film. <12> The wavelength conversion material as described in any one of <1> to <11>, which is used for image display. <13> The wavelength conversion material according to any one of <1> to <12>, wherein the phosphor includes a quantum dot phosphor. <14> The wavelength conversion material according to <13>, wherein the quantum dot phosphor includes a compound containing at least one of Cd or In. <15> A method for manufacturing a wavelength conversion material, including the step of preparing a laminate, the laminate including a resin composition layer, a coating material, and a carrier film, the resin composition layer including a phosphor and a resin, and The covering material is arranged on both sides of the resin composition layer, and the carrier film is arranged on the outer surface of at least one of the covering materials and can be peeled from the covering material; and The step of hardening the resin composition layer of the laminate. <16> A laminated body for manufacturing the wavelength conversion material according to any one of <1> to <14>, the laminated body including a covering material, and a layer disposed on one side of the covering material A carrier film that can be peeled from the covering material. <17> A backlight unit, including the wavelength conversion material according to any one of <1> to <14> and a light source. <18> An image display device including the backlight unit as described in <17>. [Effects of the invention]

According to the present disclosure, there is provided a wavelength conversion material and a manufacturing method thereof that suppress the generation of wrinkles even if the thickness is thin. In addition, according to the present disclosure, a laminate for manufacturing the wavelength conversion material, and a backlight unit and an image display device using the wavelength conversion material are provided.

Hereinafter, the mode for implementing the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, its constituent elements (including element steps, etc.) are not essential unless otherwise specified. The same is true for the numerical value and its range, which does not limit the present invention.

In the present disclosure, the numerical values described before and after "～" in the numerical range indicated by "～" are used as the minimum value and the maximum value, respectively. In the numerical ranges described stepwise in this disclosure, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of another numerical range described stepwise. In addition, in the numerical range described in the present disclosure, the upper limit or lower limit of the numerical range can be replaced with the values shown in the examples. In the present disclosure, each component may also include a plurality of corresponding substances. When there are multiple types of substances corresponding to each component in the composition, unless otherwise specified, the content rate or content of each component refers to the total content rate or content of the multiple types of substances present in the composition. In the present disclosure, a plurality of particles consistent with each component can also be included. When there are multiple types of particles corresponding to each component in the composition, unless otherwise specified, the particle size of each component refers to a value with respect to a mixture of the multiple types of particles present in the composition. In the present disclosure, the term "layer" or "film" includes not only the case formed in the entire area when the layer or film is observed, but also the case formed only in a part of the area. In the present disclosure, the term "layered" means to superimpose layers so that two or more layers can be combined, or two or more layers can be assembled and disassembled. In the present disclosure, the so-called "(meth)acrylate" refers to at least one of acrylate and methacrylate, and the so-called "(meth)allyl" refers to the combination of allyl and methallyl At least one of the "(meth)acrylic acid" refers to at least one of acrylic acid and methacrylic acid, and the "(meth)acrylic acid group" refers to at least one of the acrylic acid group and the methacrylic acid group One. In this disclosure, when the embodiment is described with reference to the drawings, the structure of the embodiment is not limited to the structure shown in the drawings. In addition, the size of the members in each figure is conceptual, and the relative relationship of the sizes between the members is not limited to this. In addition, in each drawing, the same reference numerals are attached to all the drawings for members having substantially the same function, and repeated descriptions are sometimes omitted.

"Wavelength Conversion Material (First Embodiment)" The wavelength conversion material of the first embodiment includes: a wavelength conversion layer including a phosphor and a cured resin; and a coating material, which is disposed on both sides of the wavelength conversion layer, and the wavelength conversion material is in the coating The outer surface of at least one of the materials is in a state where a carrier film that can be peeled from the covering material is arranged.

The wavelength conversion material of the above structure is provided with a carrier film that can be peeled from the coating material on the outer surface of at least one of the coating materials disposed on both sides of the wavelength conversion layer. By disposing the carrier film, even if the thickness of the covering material itself is thin, sufficient rigidity is ensured. As a result, wrinkles caused by volume shrinkage when the resin composition is cured are less likely to occur, and a good appearance can be maintained. Furthermore, since the carrier film can be peeled from the covering material, the carrier film can be removed when assembled into an image display device or the like to reduce the thickness of the wavelength conversion material.

The wavelength conversion material of the present disclosure at least includes a wavelength conversion layer and a coating material. Hereinafter, the wavelength conversion material in the state including the carrier film may be referred to as "wavelength conversion material with carrier film".

The thickness of the wavelength conversion material with a carrier film is not particularly limited, and it can be set in consideration of ensuring the necessary rigidity and handling properties. For example, it may be in the range of 100 μm to 500 μm, may be in the range of 150 μm to 400 μm, or may be in the range of 200 μm to 300 μm.

From the viewpoint of supporting a small display, the thickness of the wavelength conversion material (the total thickness of the wavelength conversion layer and the covering material) should be as small as possible. For example, it is preferably 150 μm or less, and more preferably 125 μm or less. On the other hand, from the viewpoint of obtaining a sufficient wavelength conversion function, the thickness of the wavelength conversion material is preferably 50 μm or more, more preferably 75 μm or more.

From the viewpoint of achieving both thinning of the wavelength conversion material and suppression of wrinkles, the thicker the carrier film is, the better. The thickness of the carrier film is, for example, preferably 30 μm or more, more preferably 38 μm or more, and still more preferably 50 μm or more. The upper limit of the thickness of the carrier film is not particularly limited. From the viewpoint of economic efficiency, for example, it may be 200 μm or less, 150 μm or less, 125 μm or less, or 100 μm or less. When the carrier film is arranged on the outer surfaces of the two covering materials arranged on both sides of the wavelength conversion layer, the thickness is the thickness of each carrier film.

In the present disclosure, when the carrier film includes the substrate and the adhesive layer described later, the thickness of the carrier film is the thickness including the adhesive layer.

From the viewpoint of suppressing the generation of wrinkles, the larger the value of the ratio (A/B) of the thickness A of the carrier film to the thickness B of the wavelength conversion layer, the better. For example, the value of A/B is preferably 0.4 or more, more preferably 0.6 or more, still more preferably 0.8 or more, particularly preferably 1.0 or more. If the value of A/B is 0.4 or more, the relative thickness of the carrier film with respect to the wavelength conversion layer can be sufficiently ensured, and the generation of wrinkles due to volume shrinkage when the resin composition forming the wavelength conversion layer is cured can be effectively suppressed. From the viewpoint of economy, the value of A/B may be 2.0 or less. When the carrier film is arranged on the outer surfaces of the two covering materials arranged on both sides of the wavelength conversion layer, the value is the value of the ratio of the thickness A of each carrier film to the thickness B of the wavelength conversion layer.

From the viewpoint of suppressing the generation of wrinkles, the Tg (glass transition temperature) of the carrier film is preferably 50° C. or higher, more preferably 55° C. or higher, and still more preferably 60° C. or higher. If the Tg of the carrier film is 50°C or higher, the carrier film is less likely to be deformed by heat generated when the resin composition forming the wavelength conversion layer is cured, and the generation of wrinkles due to volume shrinkage when the resin composition is cured can be effectively suppressed. From the viewpoint of the handleability of the carrier film, the Tg of the carrier film may be 150°C or lower, or 140°C or lower.

In the present disclosure, the Tg of the carrier film is a value measured by a dynamic viscoelasticity measuring device (for example, Rheometric Scientific, Solid Analyzer RSA-III). When the carrier film includes a substrate and an adhesive layer described later, the Tg of the carrier film is the Tg of the substrate.

From the viewpoint of thickness reduction of the wavelength conversion material, the thickness of the coating material is preferably 25 μm or less, and more preferably 20 μm or less. From the viewpoint of sufficiently protecting the wavelength conversion layer, the thickness of the coating material is preferably 5 μm or more, more preferably 10 μm or more. The thickness is the thickness of each of the covering materials arranged on both sides of the wavelength conversion layer.

From the viewpoint of making the wavelength conversion material thinner, the thickness of the wavelength conversion layer is preferably 120 μm or less, more preferably 100 μm or less, still more preferably 80 μm or less, and particularly preferably 75 μm or less. From the viewpoint of obtaining a sufficient wavelength conversion effect, the thickness of the wavelength conversion layer is preferably 50 μm or more, more preferably 60 μm or more, and still more preferably 65 μm or more.

The thickness of the wavelength conversion material, the wavelength conversion layer, the coating material, and the carrier film can be measured using known means such as a micrometer and an electron microscope. In the case where the thickness is not constant, the arithmetic average of the thickness of any three parts is taken as the thickness.

The carrier film is removed when the wavelength conversion material is assembled to an image display device or the like. Therefore, it is preferable that the peelability from the covering material is excellent. Specifically, the peeling force of the self-coating material measured under the condition of a peeling speed of 300 mm/min is preferably 0.7 N/25 mm or less, more preferably 0.5 N/25 mm or less, and still more preferably 0.4 N/min. Below 25 mm.

The peel force is a value measured in the following manner. Cut the wavelength conversion material into a width of 25 mm, and use a tensile testing machine at a peeling angle of 180 degrees, a peeling speed of 300 mm/min, and room temperature (25°C) to peel the carrier film from the adhesive layer. Measure the peel force (mN/25 mm) at this time. As a tensile tester, Tensilon RTA-100 (manufactured by Orientec, also used in the examples mentioned later) etc. are mentioned. However, other testing machines can also be used.

The wrinkle height of the wavelength conversion material is preferably less than 3.0 mm, more preferably less than 1.5 mm. If the wrinkle height is less than 3.0 mm, it can be judged that the generation of wrinkles is sufficiently suppressed, and the appearance of the wavelength conversion material is sufficiently good. The wrinkle height of the wavelength conversion material is a value measured by the method described in Examples described later.

An example of the schematic structure of the wavelength conversion material with a carrier film is shown in FIG. 1. However, the wavelength conversion material of the present disclosure is not limited to the structure of FIG. 1.

The wavelength conversion material 10 with a carrier film shown in FIG. 1 has: a wavelength conversion layer 11 as a cured product of a resin composition containing a phosphor, a coating material 12A provided on both sides of the wavelength conversion layer 11, and a coating The material 12B, and the carrier film 13A and the carrier film 13B arranged on the outer surfaces of the covering material 12A and the covering material 12B.

In the structure shown in FIG. 1, a carrier film 13A and a carrier film 13B are arranged on the outer surfaces of the covering material 12A and the covering material 12B, but it can also be applied to only any one of the covering material 12A and the covering material 12B. The outer surface is configured with a carrier film.

The wavelength conversion material with a carrier film of the structure shown in FIG. 1 can be manufactured by the following manufacturing method, for example.

First, a covering material (covering material with a carrier film) in a state where the carrier film is arranged on one side is prepared. The method of disposing the carrier film on one side of the covering material is not particularly limited. For example, the adhesive layer side of a carrier film with an adhesive layer formed on one side may be laminated on one side of the covering material.

Then, the resin composition for forming the wavelength conversion layer is applied to the surface of the coating material on the opposite side to the side on which the carrier film is arranged to form a resin composition layer. Another covering material with a carrier film is arranged on the resin composition layer to obtain a laminate in which the carrier film, the covering material, the resin composition layer, the covering material, and the carrier film are arranged in this order.

Then, the hardening treatment of the resin composition layer is performed. The method of hardening treatment is not particularly limited. For example, it can be performed by irradiation of active energy rays that can penetrate the carrier film and the coating material and can harden the resin contained in the resin composition layer.

By performing the curing treatment of the resin composition layer in a state where the carrier film is arranged on the outer surface of the coating material, even if the thickness of the coating material is thin, wrinkles caused by shrinkage when the resin composition layer is cured are effectively suppressed.

After the hardening treatment, the layered body is cut into a desired size as necessary. Thereby, the wavelength conversion material with the carrier film of the structure shown in FIG. 1 is obtained.

＜Wavelength conversion layer＞ The wavelength conversion layer includes a phosphor and a cured resin. By selecting the type of phosphor contained in the wavelength conversion layer, the wavelength of light incident on the wavelength conversion layer can be converted into a predetermined wavelength. For example, by including phosphors that convert blue light into red light and green light, respectively, part of the blue light incident on the wavelength conversion layer can be converted into red light and green light by the phosphor, and the transmission wavelength The blue light of the layer is converted to obtain white light.

(Phosphor) The kind of phosphor contained in the wavelength conversion layer is not particularly limited. For example, organic phosphors and inorganic phosphors can be cited. Examples of organic phosphors include naphthalimide compounds and perylene compounds. Examples of inorganic phosphors include: Y ₃ O ₃ :Eu, YVO ₄ :Eu, Y ₂ O ₂ :Eu, 3.5MgO·0.5 MgF ₂ , GeO ₂ :Mn, (Y·Cd)BO ₂ :Eu, etc. Red light-emitting inorganic phosphor, ZnS: Cu·Al, (Zn·Cd)S: Cu·Al, ZnS: Cu·Au·Al, Zn ₂ SiO ₄ : Mn, ZnSiO ₄ : Mn, ZnS: Ag·Cu, (Zn·Cd)S: Cu, ZnS: Cu, GdOS: Tb, LaOS: Tb, YSiO ₄ : Ce·Tb, ZnGeO ₄ : Mn, GeMgAlO: Tb, SrGaS: Eu ²⁺ , ZnS: Cu·Co, MgO ·NB ₂ O ₃ :Ge·Tb, LaOBr:Tb·Tm, La ₂ O ₂ S:Tb and other green light-emitting inorganic phosphors, ZnS:Ag, GaWO ₄ , Y ₂ SiO ₆ :Ce, ZnS:Ag·Ga ·Cl, Ca ₂ B ₄ OCl:Eu ²⁺ , BaMgAl ₄ O ₃ :Eu ²⁺ and other blue-emitting inorganic phosphors, quantum dot phosphors, etc.

From the viewpoint of the color reproducibility of the image display device, the wavelength conversion layer preferably contains a quantum dot phosphor as the phosphor. The type of quantum dot phosphor is not particularly limited, and examples include particles containing at least one selected from the group consisting of group II-VI compounds, group III-V compounds, group IV-VI compounds, and group IV compounds. From the viewpoint of luminous efficiency, the quantum dot phosphor preferably contains a compound containing at least one of Cd and In.

Specific examples of II-VI group compounds 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, CdHSegSTe, HgZnSeS, HgZnSeS, HgZnSe, etc. Specific examples of III-V compounds include: GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAS, GaNSb, GaPAs, GaPSb, AlNP, AlNAs , AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlPAs, InAlNP, InAlNAs, InAlPA, InAlNP, InAlPS, etc. Specific examples of Group IV-VI compounds include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbSe, SnPbSSe, SnPbSeTe, SnPbSeTe, SnPbSte, SnPbSte, and the like. Specific examples of group IV compounds include Si, Ge, SiC, SiGe, and the like.

The quantum dot phosphor may have a core-shell structure. By making the band gap of the compound constituting the shell wider than the band gap of the compound constituting the core, the quantum efficiency of the quantum dot phosphor can be further improved. Examples of the combination of core and shell (core/shell) include CdSe/ZnS, InP/ZnS, PbSe/PbS, CdSe/CdS, CdTe/CdS, CdTe/ZnS, and the like.

The quantum dot phosphor may also have a so-called core multi-shell structure in which the shell is a multilayer structure. Laminating one or more layers of shells with a narrow band gap on the core with a wide band gap, and then laminating a shell with a wide band gap on the shell, can further improve the quantum efficiency of the quantum dot phosphor.

In the case where the wavelength conversion layer contains a phosphor, the wavelength conversion layer may contain one kind of phosphor alone, or a combination of two or more kinds of phosphors. As an aspect that includes two or more phosphors in combination, for example, an aspect that includes two or more phosphors having different components but the same average particle size, and two or more phosphors that have different average particle sizes but different components can be cited. The form of the same phosphor, and the form of phosphors containing two or more components and different average particle diameters. By changing at least one of the composition and average particle diameter of the phosphor, the emission center wavelength of the phosphor can be changed.

In the case where the wavelength conversion layer contains a quantum dot phosphor as the phosphor, the proportion of the quantum dot phosphor is preferably 50% by mass or more of the entire phosphor, more preferably 70% by mass or more, and more preferably Above 80% by mass.

For example, the wavelength conversion layer may contain a phosphor G having a central emission wavelength in the green wavelength region of 520 nm to 560 nm, and a phosphor R having a central emission wavelength in the red wavelength region of 600 nm to 680 nm. When the wavelength conversion layer containing the phosphor G and the phosphor R is irradiated with excitation light in the blue wavelength region of 430 nm to 480 nm, the phosphor G and the phosphor R emit green light and red light, respectively. As a result, white light can be obtained by the green light and red light emitted from the phosphor G and the phosphor R, and the blue light transmitted through the cured resin.

The content of the phosphor in the wavelength conversion layer is, for example, preferably 0.01% by mass to 1.0% by mass of the entire wavelength conversion layer, more preferably 0.05% by mass to 0.5% by mass, and still more preferably 0.1% by mass to 0.5% by mass . If the content of the phosphor is 0.01% by mass or more of the entire wavelength conversion layer, a sufficient wavelength conversion function tends to be obtained. If the content of the phosphor is 1.0% by mass or less of the entire wavelength conversion layer, there is a fluorescent The tendency of the aggregation of light bodies to be suppressed.

(Resin cured product) The kind of resin cured product contained in the wavelength conversion layer is not particularly limited. From the viewpoint of adhesion of the wavelength conversion layer to the coating material and suppression of wrinkles due to volume shrinkage during curing, the cured resin preferably contains a sulfide structure. The cured resin containing a thioether structure can be obtained by curing, for example, a resin composition containing a thiol compound and a polymerizable carbon-carbon double bond that reacts with a thiol group to generate an enethiol Compound.

From the viewpoints of the heat resistance and moisture and heat resistance of the wavelength conversion layer, the cured resin preferably contains an alicyclic structure or an aromatic ring structure. The cured resin having an alicyclic structure or an aromatic ring structure can be obtained by curing, for example, a resin composition containing an alicyclic structure or an aromatic ring structure as a polymerizable compound described later.

From the viewpoint of suppressing the contact between the phosphor and oxygen, the cured resin preferably contains an alkoxy group. If the cured resin contains an alkoxy group, the polarity of the cured resin increases, and non-polar oxygen tends to be difficult to dissolve in the components of the cured product. In addition, there is a tendency for the flexibility of the cured resin to increase and the adhesion to the covering material to improve.

The cured resin containing an alkoxyl group can be obtained by curing, for example, a resin composition containing an alkoxyl group as a polymerizable compound described later.

(Light diffusion material) The wavelength conversion layer may further include a light diffusion material. By including the light diffusing material, the light incident on the wavelength conversion layer can be scattered, thereby improving the wavelength conversion efficiency of the phosphor.

The type of the light diffusion material contained in the wavelength conversion layer is not particularly limited, and examples thereof include titanium oxide, barium sulfate, zinc oxide, calcium carbonate, and the like. Among these, from the viewpoint of light scattering efficiency, titanium oxide is preferred. The titanium oxide may be rutile-type titanium oxide or anatase-type titanium oxide, and is preferably rutile-type titanium oxide.

When the light diffusion material contains titanium oxide, the proportion of titanium oxide is preferably 50% by mass or more of the entire light diffusion material, more preferably 70% by mass or more, and still more preferably 80% by mass or more.

The amount of the light diffusion material in the wavelength conversion layer is not particularly limited, and can be adjusted according to the desired wavelength conversion efficiency, light transmittance, and the like. For example, the content of the light diffusion material is preferably 0.1% by mass to 10.0% by mass of the entire wavelength conversion layer, more preferably 1.0% by mass to 7.5% by mass, and still more preferably 2.0% by mass to 5.0% by mass.

The average particle size of the light diffusion material is preferably 0.1 μm to 1 μm, more preferably 0.2 μm to 0.8 μm, and still more preferably 0.2 μm to 0.5 μm.

In the present disclosure, the average particle size of the light diffusion material can be measured in the following manner. The light diffusing material (when the light diffusing material is contained in the wavelength conversion layer or the resin composition described later, the extracted light diffusing material) is dispersed in purified water containing a surfactant to obtain a dispersion liquid. When using this dispersion liquid to measure the volume-based particle size distribution by a laser diffraction particle size distribution measuring device (for example, Shimadzu Corporation, SALD-3000J), when the cumulative amount from the small diameter side reaches 50% The value of (median particle diameter (D50)) is the average particle diameter (volume average particle diameter) of the light diffusion material. As a method of extracting the light diffusion material from the resin composition, for example, it can be obtained by diluting the resin composition with a liquid medium, and separating and recovering the light diffusion material by precipitation by centrifugal separation treatment or the like. When the light diffusing material is contained in the wavelength conversion layer, the cross section of the wavelength conversion layer can be observed using a scanning electron microscope to calculate the circle equivalent diameter (the geometry of the major and minor diameters) of 50 particles. Average), and the value obtained as the arithmetic average of the circle-equivalent diameter is defined as the average particle diameter.

From the viewpoint of enhancing the dispersibility in the wavelength conversion layer, the light diffusion material preferably has an organic layer containing an organic substance on at least a part of the surface. Examples of the organic substances contained in the organic substance layer include organosilanes, organosiloxanes, fluorosilanes, organophosphates, organophosphate compounds, organophosphinates, organosulfonic acid compounds, carboxylic acids, carboxylic acid esters, and carboxylates. Acid derivatives, amides, hydrocarbon waxes, polyolefins, polyolefin copolymers, polyols, polyol derivatives, alkanolamines, alkanolamine derivatives, organic dispersants, etc. The organic substance contained in the organic substance layer preferably contains polyol, organosilane, etc., and more preferably contains at least one of polyol or organosilane. Specific examples of organosilanes include: octyltriethoxysilane, nonyltriethoxysilane, decyltriethoxysilane, dodecyltriethoxysilane, and tridecyltriethoxysilane. Oxysilane, tetradecyl triethoxy silane, pentadecyl triethoxy silane, hexadecyl triethoxy silane, heptadecyl triethoxy silane, octadecyl triethyl Oxysilane and so on. Specific examples of organosiloxanes include: polydimethyl siloxane (PDMS), polymethyl hydrosiloxane (PMHS), PMHS terminated with trimethylsilyl groups Polysiloxanes derived from functionalization (hydrosilation) of olefins, etc. Specific examples of organic phosphates include, for example, n-octyl phosphonic acid and its esters, n-decyl phosphonic acid and its esters, 2-ethylhexyl phosphonic acid and its esters, and camphor group (camphyl) phosphonic acid and its ester. As a specific example of an organic phosphoric acid compound, an organic acidic phosphoric acid ester, an organic pyrophosphate, an organic polyphosphate, an organic metaphosphate, these salts, etc. are mentioned. Specific examples of organic phosphinic acid esters include, for example, n-hexyl phosphinic acid and its esters, n-octyl phosphinic acid and its esters, di-n-hexyl phosphinic acid and its esters, and di-n-octyl phosphinic acid. Phosphonic acid and its esters. Specific examples of organic sulfonic acid compounds include alkyl sulfonic acids such as hexyl sulfonic acid, octyl sulfonic acid and 2-ethylhexyl sulfonic acid, these alkyl sulfonic acids and sodium, calcium, magnesium, aluminum, Salts such as metal ions such as titanium, ammonium ions, and organic ammonium ions such as triethanolamine. Specific examples of carboxylic acids include maleic acid, malonic acid, fumaric acid, benzoic acid, phthalic acid, stearic acid, oleic acid, linoleic acid, and the like. Specific examples of carboxylic acid esters include the combination of the carboxylic acid and ethylene glycol, propylene glycol, trimethylolpropane, diethanolamine, triethanolamine, glycerin, hexanetriol, erythritol, and mannitol. , Sorbitol, pentaerythritol, bisphenol A, hydroquinone, phloroglucinol and other hydroxyl compounds generated by the reaction of esters and partial esters. Specific examples of amides include amide stearate, amide oleate, and erucamide. Specific examples of polyolefins and their copolymers include copolymers of polyethylene, polypropylene, ethylene and one or two or more compounds selected from propylene, butene, vinyl acetate, acrylate, acrylamide, etc. Things and so on. As a specific example of a polyhydric alcohol, glycerol, trimethylolethane, trimethylolpropane, etc. are mentioned. As a specific example of alkanolamine, diethanolamine, triethanolamine, etc. are mentioned. Specific examples of the organic dispersant include citric acid, polyacrylic acid, polymethacrylic acid, and polymer organic dispersants having functional groups such as anionic, cationic, amphoteric, and nonionic.

From the viewpoint of improving the dispersibility in the wavelength conversion layer, the light diffusion material may have an oxide layer containing an oxide on at least a part of the surface. Examples of oxides contained in the oxide layer include silicon dioxide, aluminum oxide, zirconium oxide, phosphoria, boria, and the like. The oxide layer may be one layer or two or more layers. In the case where the light diffusion material has two oxide layers, it is preferably one having a first oxide layer containing silicon dioxide and a second oxide layer containing aluminum oxide.

When the light diffusion material has an organic layer and an oxide layer containing organic matter, the oxide layer and the organic layer are preferably provided in the order of the oxide layer and the organic layer on the surface of the light diffusion material. In the case where the light diffusion material has an organic layer and two oxide layers, on the surface of the light diffusion material, the first oxide layer containing silicon dioxide, the second oxide layer containing aluminum oxide, and the organic layer are compared. Preferably, they are provided in the order of the first oxide layer, the second oxide layer, and the organic layer (the organic layer becomes the outermost layer).

The wavelength conversion layer may be a cured product of a composition (hereinafter, also simply referred to as a resin composition) containing a phosphor, a polymerizable compound, a photopolymerization initiator, and, if necessary, a light diffusion material. The resin composition preferably contains a thiol compound and at least one selected from the group consisting of a (meth)acrylic compound and a (meth)allyl compound as a polymerizable compound. The resin composition may optionally contain other components.

(Fluorescent body) The details of the phosphor contained in the resin composition are as described above. The phosphor can be used in the state of a phosphor dispersion liquid dispersed in a dispersion medium. As the dispersion medium in which the phosphor is dispersed, various organic solvents, silicone compounds, and monofunctional (meth)acrylate compounds can be cited. The fluorescent body can also be used in the state of a fluorescent body dispersion liquid using a dispersing agent as necessary.

The organic solvent that can be used as a dispersion medium is not particularly limited as long as precipitation and aggregation of the phosphor are not confirmed, and examples include acetonitrile, methanol, ethanol, acetone, 1-propanol, ethyl acetate, and butyl acetate , Toluene, hexane, etc.

As the silicone compound that can be used as a dispersion medium, there can be mentioned: dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrosilicone oil, and other straight silicone oils (straight silicone oil); Silicone oil, epoxy modified silicone oil, carboxy modified silicone oil, methanol modified silicone oil, mercapto modified silicone oil, heterofunctional group modified silicone oil, polyether modified silicone oil Modification of oil, methylstyrene-based modified silicone oil, hydrophilic special modified silicone oil, high-grade alkoxy modified silicone oil, high-grade fatty acid modified silicone oil, fluorine-modified silicone oil, etc. Silicone oil, etc.

The monofunctional (meth)acrylate compound that can be used as a dispersion medium is not particularly limited as long as it is liquid at room temperature (25°C), and monofunctional (meth)acrylate having an alicyclic structure can be mentioned. Compound (preferably isobornyl (meth)acrylate and dicyclopentyl (meth)acrylate), methoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) Acrylate, ethoxylated o-phenylphenol (meth)acrylate, etc.

As a dispersing agent used as needed, polyetheramine (JEFFAMINE M-1000, Huntsman) etc. can be mentioned.

The mass-based ratio of the phosphor in the phosphor dispersion is preferably 1% by mass to 20% by mass, more preferably 1% by mass to 10% by mass.

When the proportion of the phosphor in the phosphor dispersion on the basis of mass is 1% to 20% by mass, relative to the total amount of the resin composition, the amount of the phosphor dispersion in the resin composition The content rate is, for example, preferably 1% by mass to 10% by mass, more preferably 4% by mass to 10% by mass, and still more preferably 4% by mass to 7% by mass. In addition, relative to the total amount of the resin composition, the content of the phosphor in the resin composition is, for example, preferably 0.01% by mass to 1.0% by mass, more preferably 0.05% by mass to 0.5% by mass, and still more preferably 0.1 Mass%～0.5% by mass. If the content of the phosphor is 0.01% by mass or more, there is a tendency that sufficient luminous intensity can be obtained when the cured product is irradiated with excitation light. If the content of the phosphor is 1.0% by mass or less, there is a phosphor The tendency of agglomeration to be suppressed.

(Polymerizable compound) The resin composition contains a polymerizable compound. The polymerizable compound contained in the resin composition is not particularly limited, and examples thereof include thiol compounds, (meth)acrylic compounds, and (meth)allyl compounds. In addition, the (meth)allyl compound refers to a compound having a (meth)allyl group in the molecule, and the (meth)acrylic compound refers to a compound having a (meth)acryloyl group in the molecule. For convenience, compounds having both (meth)allyl and (meth)acrylic groups in the molecule are classified as (meth)allyl compounds.

From the viewpoint of the adhesiveness of the wavelength conversion layer with respect to the coating material, the resin composition preferably contains a thiol compound and a group selected from the group consisting of (meth)acrylic compounds and (meth)allyl compounds. At least one of the group is used as a polymerizable compound.

The cured product obtained by curing a resin composition containing a thiol compound and at least one selected from the group consisting of a (meth)acrylic compound and a (meth)allyl compound as a polymerizable compound contains The thioether structure formed by the enthiol reaction between the thiol group and the carbon-carbon double bond of the (meth)acryloyl group or (meth)allyl group (RS-R', R and R'represent organic base). This tends to improve the adhesion of the wavelength conversion layer to the coating material. In addition, the optical properties of the wavelength conversion layer tend to be further improved. Hereinafter, the thiol compound, the (meth)acrylic compound, and the (meth)allyl compound will be described in detail.

A. Thiol compounds The thiol compound may be a monofunctional thiol compound having one thiol group in one molecule, or a multifunctional thiol compound having two or more thiol groups in one molecule. The thiol compound contained in the resin composition may be only one type or two or more types.

The thiol compound may have a polymerizable group other than a thiol group (for example, a (meth)acryloyl group and a (meth)allyl group) in the molecule, or may not have it. In the present disclosure, a compound containing a thiol group and a polymerizable group other than the thiol group in the molecule is classified as a "thiol compound".

Specific examples of monofunctional thiol compounds include: hexyl mercaptan, 1-heptane mercaptan, 1-octyl mercaptan, 1-nonane mercaptan, 1-decane mercaptan, 3-mercaptopropionic acid, mercaptopropionic acid Methyl ester, methoxybutyl mercaptopropionate, octyl mercaptopropionate, tridecyl mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, n-octyl-3-mercaptopropionate, etc. .

Specific examples of polyfunctional thiol compounds include: ethylene glycol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptopropionate), tetraethylene glycol bis(3-mercaptopropionate) Acid ester), 1,2-propanediol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptobutyrate), 1,4-butanediol bis(3-mercaptopropionate), 1,4-Butanediol bis(3-mercaptobutyrate), 1,8-octanediol bis(3-mercaptopropionate), 1,8-octanediol bis(3-mercaptobutyrate) , Hexanediol dithioglycolate, trimethylolpropane tris (3-mercaptopropionate), trimethylolpropane tris (3-mercaptobutyrate), trimethylolpropane tris (3- Mercapto isobutyrate), trimethylolpropane tris (2-mercaptoisobutyrate), trimethylolpropane trithioglycolate, tris-[(3-mercaptopropionyloxy)-ethyl ]-Isocyanurate, trimethylolethane tris(3-mercaptobutyrate), pentaerythritol tetra(3-mercaptopropionate), pentaerythritol tetra(3-mercaptobutyrate), pentaerythritol tetra(3-mercaptobutyrate) 3-mercaptoisobutyrate), pentaerythritol tetra(2-mercaptoisobutyrate), dipentaerythritol hexa(3-mercaptopropionate), dipentaerythritol hexa(2-mercaptopropionate), dipentaerythritol hexa(3 -Mercaptobutyrate), dipentaerythritol hexa(3-mercaptoisobutyrate), dipentaerythritol hexa(2-mercaptoisobutyrate), pentaerythritol tetrathioglycolate, dipentaerythritol hexathioglycolate, etc. .

From the viewpoint of further improving the adhesiveness of the wavelength conversion layer with respect to the coating material, heat resistance, and moisture and heat resistance, the thiol compound preferably contains a multifunctional thiol compound. The ratio of the polyfunctional thiol compound to the total amount of the thiol compound is, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 100% by mass.

The thiol compound may be in the form of a thioether oligomer formed by reacting with a (meth)acrylic compound. The thioether oligomer can be obtained by addition polymerization of a thiol compound and a (meth)acrylic compound in the presence of a polymerization initiator.

When the resin composition contains a thiol compound, relative to the total amount of the resin composition, the content of the thiol compound in the resin composition is, for example, preferably 5 mass% to 80 mass%, more preferably 15 mass% ~70% by mass, more preferably 20% by mass to 60% by mass. If the content of the thiol compound is 5% by mass or more, the adhesion of the wavelength conversion layer to the coating material tends to be further improved. If the content of the thiol compound is 80% by mass or less, there is a tendency for the wavelength conversion layer The heat resistance and heat and humidity resistance tend to be further improved.

B. (Meth) acrylic compound The (meth)acrylic compound may be a monofunctional (meth)acrylic compound having one (meth)acrylic acid group in one molecule, or it may have two or more (meth)acrylic acid groups in one molecule The multifunctional (meth)acrylic compound. The (meth)acrylic compound contained in the resin composition may be one type or two or more types.

Specific examples of the monofunctional (meth)acrylic compound include: (meth)acrylic acid; methyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, (meth)acrylic acid; Base) 2-ethylhexyl acrylate, isononyl (meth)acrylate, n-octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, etc. Alkyl (meth)acrylates of 1 to 18; (meth)acrylate compounds having aromatic rings such as benzyl (meth)acrylate and phenoxyethyl (meth)acrylate; (methyl) ) Alkoxyalkyl (meth)acrylates such as butoxyethyl acrylate; Aminoalkyl (meth)acrylates such as N,N-dimethylaminoethyl (meth)acrylate; Diethylene glycol monoethyl ether (meth) acrylate, triethylene glycol monobutyl ether (meth) acrylate, tetraethylene glycol monomethyl ether (meth) acrylate, hexaethylene glycol monomethyl ether (meth) Base) acrylate, octaethylene glycol monomethyl ether (meth)acrylate, nonaethylene glycol monomethyl ether (meth)acrylate, dipropylene glycol monomethyl ether (meth)acrylate, heptapropylene glycol monomethyl ether Polyalkylene glycol monoalkyl ether (meth)acrylate such as (meth)acrylate, tetraethylene glycol monoethyl ether (meth)acrylate, etc.; hexaethylene glycol monophenyl ether (meth)acrylate Polyalkylene glycol monoaryl ether (meth)acrylate; cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, isobornyl (meth)acrylate, formaldehyde addition cyclodecyl (Meth)acrylate compounds having an alicyclic structure such as triene (meth)acrylate; (meth)acrylate compounds having a heterocyclic ring such as (meth)acryloylmorpholine, tetrahydrofurfuryl (meth)acrylate, etc. Yl)acrylate compound; fluorinated alkyl (meth)acrylate such as heptafluorodecyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate , 4-hydroxybutyl (meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, octapropylene glycol (Meth)acrylate compounds having hydroxyl groups such as mono(meth)acrylate; (meth)acrylate compounds having glycidyl groups such as glycidyl (meth)acrylate; isocyanate 2-(2 -(Meth)acrylic acid ester compounds having isocyanate groups such as (meth)acryloyloxyethoxy) ethyl, isocyanate 2-(meth)acryloyloxyethyl, etc.; tetraethylene glycol mono (Meth)acrylate, hexaethylene glycol mono(meth)acrylate, octapropylene glycol mono(meth)acrylate and other polyalkylene glycol mono(meth)acrylates; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, N,N -(Meth)acrylamide compounds such as diethyl (meth)acrylamide and 2-hydroxyethyl (meth)acrylamide.

Specific examples of the polyfunctional (meth)acrylic compound include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9- Alkylene glycol di(meth)acrylate such as nonanediol di(meth)acrylate; Polyalkylene glycol such as polyethylene glycol di(meth)acrylate and polypropylene glycol di(meth)acrylate Di(meth)acrylate; trimethylolpropane tri(meth)acrylate, ethylene oxide addition trimethylolpropane tri(meth)acrylate, isocyanuric acid tris(2-propylene) Tri(meth)acrylate compounds such as oxyethyl) ester; ethylene oxide addition pentaerythritol tetra(meth)acrylate, trimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate Tetra(meth)acrylate compounds such as acrylate; tricyclodecane dimethanol di(meth)acrylate, cyclohexane dimethanol di(meth)acrylate, 1,3-adamantane dimethanol Di (meth) acrylate, hydrogenated bisphenol A (poly) ethoxy bis (meth) acrylate, hydrogenated bisphenol A (poly) propoxy bis (meth) acrylate, hydrogenated bisphenol F (poly) ) Ethoxy bis (meth) acrylate, hydrogenated bisphenol F (poly) propoxy bis (meth) acrylate, hydrogenated bisphenol S (poly) ethoxy bis (meth) acrylate, hydrogenated bisphenol (Meth)acrylate compounds having an alicyclic structure such as phenol S (poly)propoxydi(meth)acrylate.

From the viewpoint of further improving the heat resistance and moisture and heat resistance of the cured product, the (meth)acrylic compound is preferably a (meth)acrylate compound having an alicyclic structure or an aromatic ring structure. As an alicyclic structure or an aromatic ring structure, an isobornyl skeleton, a tricyclodecane skeleton, a bisphenol skeleton, etc. are mentioned.

The (meth)acrylic compound may be one having an alkoxyl group, and may be a difunctional (meth)acrylic compound having an alkoxyl group.

As the alkoxyl group, for example, an alkoxyl group having 2 to 4 carbon atoms is preferred, an alkoxyl group having 2 or 3 carbon atoms is more preferred, and an alkoxyl group having 2 carbon atoms is more preferred. . The alkoxylate group contained in the (meth)acrylic compound may be one type or two or more types.

The alkoxyl group-containing compound may also be a polyalkyleneoxy group-containing compound having a polyalkoxyl group containing a plurality of alkoxyl groups.

In the case where the (meth)acrylic compound has alkoxylate groups, the number of alkoxylate groups in one molecule is preferably 2 to 30, more preferably 2 to 20, and still more preferably 3. Pieces to 10 pieces, particularly preferably 3 to 5 pieces.

When the (meth)acrylic compound has an alkoxyl group, it preferably has a bisphenol structure. This tends to be more excellent in heat resistance of the cured product. Examples of the bisphenol structure include a bisphenol A structure and a bisphenol F structure, and among them, a bisphenol A structure is preferred.

Specific examples of the (meth)acrylic compound having an alkoxy group include: (meth)acrylic acid alkoxyalkyl esters such as butoxyethyl (meth)acrylate; diethylene glycol monoethyl ether (Meth)acrylate, triethylene glycol monobutyl ether (meth)acrylate, tetraethylene glycol monomethyl ether (meth)acrylate, hexaethylene glycol monomethyl ether (meth)acrylate, eight Ethylene glycol monomethyl ether (meth)acrylate, nonaethylene glycol monomethyl ether (meth)acrylate, dipropylene glycol monomethyl ether (meth)acrylate, heptapropylene glycol monomethyl ether (meth)acrylate , Polyalkylene glycol monoalkyl ether (meth)acrylate such as tetraethylene glycol monoethyl ether (meth)acrylate; Polyalkylene glycol such as hexaethylene glycol monophenyl ether (meth)acrylate Monoaryl ether (meth)acrylate; (meth)acrylate compounds having heterocycles such as tetrahydrofurfuryl (meth)acrylate; triethylene glycol mono(meth)acrylate, tetraethylene glycol (Meth)acrylate compounds having hydroxyl groups such as mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, and octapropylene glycol mono(meth)acrylate; glycidyl (meth)acrylate (Meth)acrylate compounds having glycidyl groups; polyalkylene glycol di(meth)acrylates such as polyethylene glycol di(meth)acrylate and polypropylene glycol di(meth)acrylate; Addition of ethylene oxide to trimethylolpropane tri(meth)acrylate and other tri(meth)acrylate compounds; addition of ethylene oxide to pentaerythritol tetra(meth)acrylate and other tetra(meth)acrylate compounds Acrylate compound; ethoxylated bisphenol A type di(meth)acrylate, propoxylated bisphenol A type di(meth)acrylate, propoxylated ethoxylated bisphenol A type bis( Bisphenol type di(meth)acrylate compounds such as meth)acrylate. As the alkoxy-containing compound, among them, ethoxylated bisphenol A type di(meth)acrylate, propoxylated bisphenol A type di(meth)acrylate, and propoxylated ethyl acrylate are preferred. The oxylated bisphenol A type di(meth)acrylate is more preferably the ethoxylated bisphenol A type di(meth)acrylate.

When the resin composition contains a (meth)acrylic compound, the content of the (meth)acrylic compound in the resin composition may be, for example, 40% by mass to 90% by mass relative to the total amount of the resin composition. It can be 50% to 80% by mass.

C. (Methyl) allyl compound The (meth)allyl compound may be a monofunctional (meth)allyl compound having one (meth)allyl group in one molecule, or it may be a monofunctional (meth)allyl compound having two or more (methyl) allyl groups in one molecule. ) Allyl polyfunctional (meth)allyl compounds. The (meth)allyl compound contained in the resin composition may be only one type or two or more types.

The (meth)allyl compound may or may not have a polymerizable group other than the (meth)allyl group (for example, a (meth)acryloyl group) in the molecule. In the present disclosure, compounds having polymerizable groups other than (meth)allyl groups in the molecule (excluding thiol compounds) are classified as "(meth)allyl compounds".

Specific examples of monofunctional (meth)allyl compounds include (meth)allyl acetate, (meth)allyl n-propionate, (meth)allyl benzoate, and acetic acid ( (Meth)allyl phenyl ester, (meth)allyl phenoxy acetate, (meth)allyl methyl ether, (meth)allyl glycidyl ether, etc.

Specific examples of polyfunctional (meth)allyl compounds include di(meth)allyl benzenedicarboxylate, di(meth)allyl cyclohexanedicarboxylate, and maleic Di(meth)allyl acid, di(meth)allyl adipate, di(meth)allyl phthalate, di(meth)allyl isophthalate, p-benzene Di(meth)allyl dicarboxylate, glycerol bis(meth)allyl ether, trimethylolpropane bis(meth)allyl ether, pentaerythritol bis(meth)allyl ether, isotrimethyl 1,3-bis(meth)allyl-5-glycidyl cyanurate, tri(meth)allyl cyanurate, tri(meth)allyl isocyanurate, partial Tris(meth)allyl trimellitate, tetra(meth)allyl pyromellitate, 1,3,4,6-tetra(meth)allyl glycoluril, 1,3,4, 6-Tetra(meth)allyl-3a-methyl glycoluril, 1,3,4,6-tetra(meth)allyl-3a,6a-dimethyl glycoluril, etc.

From the viewpoints of the heat resistance and heat resistance of the cured product, the (meth)allyl compound is preferably selected from the group consisting of tri(meth)allyl isocyanurate and the like. The group consisting of backbone compounds, tris(meth)allyl cyanurate, bis(meth)allyl benzenedicarboxylate, and bis(meth)allyl cyclohexanedicarboxylate At least one of them is more preferably a compound having an isocyanurate skeleton, and still more preferably tri(meth)allyl isocyanurate.

When the resin composition contains a (meth)allyl compound, the content rate of the (meth)allyl compound in the resin composition may be, for example, 10% by mass to 50% relative to the total amount of the resin composition. The mass% may be 15% to 45% by mass.

In one embodiment, the polymerizable compound may include a thioether oligomer as a thiol compound and a (meth)allyl compound (preferably a polyfunctional (meth)allyl compound).

When the polymerizable compound contains a thioether oligomer and a (meth)allyl compound as a thiol compound, and a phosphor is used as the phosphor, the phosphor is preferably dispersed in a dispersion medium. The state of the dispersion in the silicone compound.

In one embodiment, the polymerizable compound may also be a compound containing a thiol compound and not being a thioether oligomer, and a (meth)acrylic compound (preferably a polyfunctional (meth)acrylic compound, More preferably, it is a difunctional (meth)acrylic compound).

In the case where the polymerizable compound includes a thiol compound and a non-thioether oligomer compound and a (meth)acrylic compound, and a quantum dot phosphor is used as the phosphor, the quantum dot phosphor is more It is preferably dispersed in a (meth)acrylic compound as a dispersion medium, preferably a monofunctional (meth)acrylic compound, and more preferably in the state of a dispersion liquid in isobornyl (meth)acrylate.

(Photopolymerization initiator) The type of the photopolymerization initiator contained in the resin composition is not particularly limited, and examples thereof include compounds that generate radicals by irradiation with active energy rays such as ultraviolet rays.

Specific examples of the photopolymerization initiator include benzophenone, N,N'-tetraalkyl-4,4'-diaminobenzophenone, and 2-benzyl-2-dimethyl Amino-1-(4-morpholinylphenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl-acetone-1, 4 ,4'-bis(dimethylamino)benzophenone (also known as "Michler's ketone"), 4,4'-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylamino benzophenone, 1-hydroxycyclohexyl phenyl ketone, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane- 1-ketone, 1-(4-(2-hydroxyethoxy)-phenyl)-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-2-methyl-1- Aromatic ketone compounds such as phenylpropane-1-one; quinone compounds such as alkylanthraquinone and phenanthrenequinone; benzoin compounds such as benzoin and alkylbenzoin; benzoin ether compounds such as benzoin alkyl ether and benzoin phenyl ether ; Benzyl derivatives such as benzyl dimethyl ketal; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5- Di(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5- Diphenylimidazole dimer, 2,4-bis(p-methoxyphenyl)-5-phenylimidazole dimer, 2-(2,4-dimethoxyphenyl)-4,5- 2,4,5-triarylimidazole dimer such as diphenylimidazole dimer; 9-phenyl acridine, 1,7-(9,9'-acridinyl)heptane, etc. acridine derivative物; 1,2-octanedione 1-[4-(phenylthio)-2-(O-benzyl oxime)], ethyl ketone 1-[9-ethyl-6-(2-methyl Benzoyl)-9H-carbazol-3-yl]-1-(O-acetoxyoxime) and other oxime ester compounds; 7-diethylamino-4-methylcoumarin, etc. Legume compounds; thioxanthone compounds such as 2,4-diethylthioxanthone; 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, 2,4,6- Trimethylbenzyl-phenyl-ethoxy-phosphine oxide and other phosphine oxide compounds. The resin composition may contain one kind of photopolymerization initiator alone, or may contain two or more kinds of photopolymerization initiators in combination.

From the standpoint of curability, the photopolymerization initiator is preferably at least one selected from the group consisting of oxyphosphine oxide compounds, aromatic ketone compounds, and oxime ester compounds, and more preferably selected from the group consisting of oxyphosphine oxide compounds, aromatic ketone compounds, and oxime ester compounds. At least one of the group consisting of a phosphine oxide compound and an aromatic ketone compound is more preferably an acyl phosphine oxide compound.

Relative to the total amount of the resin composition, the content of the photopolymerization initiator in the resin composition is, for example, preferably 0.1% by mass to 5% by mass, more preferably 0.1% by mass to 3% by mass, and still more preferably 0.1 Mass% to 1.5% by mass. If the content of the photopolymerization initiator is 0.1% by mass or more, the sensitivity of the resin composition tends to become sufficient, and if the content of the photopolymerization initiator is 5% by mass or less, there is a tendency for the resin composition The influence of hue and the decrease in storage stability tend to be suppressed.

(Light diffusion material) The details of the light diffusion material contained in the resin composition are as described above.

(Other ingredients) The resin composition may further contain components other than the above-mentioned components. For example, the resin composition may further contain components such as a solvent, a dispersion medium, a polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion-imparting agent, and an antioxidant. Each component may be used individually by 1 type, and may use 2 or more types together.

(Preparation method of resin composition) The resin composition can be prepared by mixing a phosphor, a polymerizable compound, a photopolymerization initiator, and other components as necessary by a conventional method.

The wavelength conversion layer may be formed by curing one resin composition, or may be formed by curing two or more resin compositions. For example, in the case where the wavelength conversion material is in the form of a film, the wavelength conversion layer may be laminated with a first cured layer formed by curing a resin composition containing a first phosphor, and a first cured layer formed by curing a resin composition containing a first phosphor, A second cured layer formed by curing a resin composition of a second phosphor with a different light body.

From the viewpoint of further improving adhesion, the loss tangent (tanδ) of the wavelength conversion layer measured by dynamic viscoelasticity at a frequency of 10 Hz and a temperature of 25°C is preferably 0.4 to 1.5, more preferably 0.4 ~1.2, more preferably 0.4 to 0.6. The loss tangent (tanδ) of the wavelength conversion layer can be measured using a dynamic viscoelasticity measuring device (for example, Rheometric Scientific, Solid Analyzer RSA-III).

From the viewpoint of further improving adhesion, heat resistance, and moisture and heat resistance, the glass transition temperature (Tg) of the wavelength conversion layer is preferably 85°C or higher, more preferably 85°C to 160°C, and still more preferably 90°C ～120℃. The glass transition temperature (Tg) of the wavelength conversion layer can be measured using a dynamic viscoelasticity measuring device (for example, Rheometric Scientific, Solid Analyzer RSA-III) at a frequency of 10 Hz.

In addition, from the viewpoint of further improving adhesion, heat resistance, and moisture and heat resistance, the storage elastic coefficient of the wavelength conversion layer measured under the conditions of a frequency of 10 Hz and a temperature of 25° C. is preferably 1×10 ⁷ Pa~ 1×10 ¹⁰ Pa, more preferably 5×10 ⁷ Pa to 1×10 ¹⁰ Pa, still more preferably 5×10 ⁷ Pa to 5×10 ⁹ Pa. The storage elastic coefficient of the cured resin can be measured using a dynamic viscoelasticity measuring device (for example, Rheometric Scientific, Solid Analyzer RSA-III).

The wavelength conversion layer can be obtained, for example, by forming a coating film, a molded body, etc. of the resin composition, and drying treatment as necessary, and then irradiating active energy rays such as ultraviolet rays. The wavelength and irradiation amount of the active energy rays can be appropriately set according to the composition of the resin composition. In one aspect, ultraviolet rays with a wavelength of 280 nm to 400 nm are irradiated with an irradiation amount of ^{100 mJ/cm 2} to 5000 mJ/cm ^2. Examples of ultraviolet sources include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and the like.

＜Covering material＞ The covering material is arranged on both sides of the wavelength conversion layer. Thereby, the penetration of moisture, oxygen, etc. into the wavelength conversion layer is suppressed, and the deterioration of the wavelength conversion layer is suppressed. In addition, appropriate rigidity is imparted to the wavelength conversion material to improve handling properties.

The material of the coating material is not particularly limited, and it can be polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN); polyethylene (PE), polypropylene (PP) And other polyolefins; nylon and other polyamides; ethylene-vinyl alcohol copolymer (EVOH), etc. From the viewpoint of easy availability, the material of the covering material is preferably polyethylene terephthalate.

The coating material may also include a barrier layer (barrier film) for strengthening the barrier function against water, oxygen, and the like. As the barrier layer, an inorganic layer containing an inorganic substance such as aluminum oxide and silicon dioxide can be cited. When the covering material has a barrier layer, it is preferable to arrange the barrier layer on the side in contact with the wavelength conversion layer.

The oxygen permeability of the coating material is, for example, preferably 1.0 mL/(m ² ·24 h·atm) or less, more preferably 0.8 mL/(m ² ·24 h·atm) or less, and still more preferably 0.6 mL/( m ² ·24 h·atm) or less. The oxygen transmission rate of the coating material can be measured using an oxygen transmission rate measuring device (for example, MOCON company, OX-TRAN) at a temperature of 23° C. and a relative humidity of 90%.

In addition, the water vapor transmission rate of the coating material is, for example, preferably 1×10 ⁰ g/(m ² ·24 h) or less, more preferably 8×10 ^-1 g/(m ² ·24 h) or less, and more It is preferably 6×10 ^-1 g/(m ² ·24 h) or less. The water vapor transmission rate of the coating material can be measured using a water vapor transmission rate measuring device (for example, MOCON, AQUATRAN) at a temperature of 40° C. and a relative humidity of 100%.

＜Carrier film＞ The material of the carrier film is not particularly limited. For example, it can be polyester such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin such as polyethylene (PE) and polypropylene (PP); polyolefin such as nylon Amide; ethylene-vinyl alcohol copolymer (EVOH), etc. From the viewpoint of easy availability, the material of the covering material is preferably polyethylene terephthalate.

From the viewpoint of ensuring the adhesion to the covering material, the carrier film preferably includes an adhesive layer on the surface on the side in contact with the covering material. The adhesive layer preferably contains adhesives such as acrylic adhesives, rubber adhesives, silicone adhesives, and urethane adhesives, among which acrylic adhesives are preferably included. The thickness of the adhesive layer is not particularly limited, and for example, it may be in the range of 1 μm to 10 μm.

"Wavelength Conversion Material (Second Embodiment)" The wavelength conversion material of the second embodiment includes: a wavelength conversion layer including a phosphor and a cured resin; and a coating material disposed on both sides of the wavelength conversion layer, the wavelength conversion layer and the coating material The total thickness is 150 μm or less.

The details and preferred aspects of the wavelength conversion material, wavelength conversion layer, and cladding material of the second embodiment are the same as those of the wavelength conversion material, wavelength conversion layer, and cladding material of the first embodiment .

The wavelength conversion material of the second embodiment may be provided with a carrier film on the outer surface of at least one of the coating materials. The details and preferred aspects of the carrier film are the same as those of the carrier film included in the wavelength conversion material of the first embodiment.

"Manufacturing Method of Wavelength Conversion Material" The method of manufacturing a wavelength conversion material of the present disclosure is a method of manufacturing a wavelength conversion material that includes the steps of preparing a laminate, the laminate including a resin composition layer, a coating material, and a carrier film, and the resin composition layer Comprising a phosphor and a resin, the covering material is arranged on both sides of the resin composition layer, and the carrier film is arranged on the outer surface of at least one of the covering materials and can be removed from the covering material Peeling; and a step of hardening the resin composition layer of the laminate.

In the method, the resin composition is cured in a state where the carrier film is arranged on the outer surface of at least one of the coating materials. Therefore, even if the thickness of the wavelength conversion material is thin, it is possible to suppress the generation of wrinkles accompanying the volume shrinkage when the resin composition is cured, and it is possible to produce a wavelength conversion material with a good appearance.

In the method, the step of preparing a laminate including a resin composition layer, a coating material, and a carrier film is not particularly limited. For example, a resin composition may be coated on a covering material with a carrier film arranged on one side to form a resin composition layer, and another covering material may be arranged on the resin composition layer.

The method of disposing the carrier film on one side of the covering material is not particularly limited. For example, it can be formed by laminating the adhesive layer side of a carrier film having an adhesive layer on a covering material.

In the above method, the method of hardening the resin composition layer is not particularly limited. For example, it can be performed by irradiating active energy rays that can pass through the coating material and the carrier film and can harden the resin composition layer.

The method may be a method of manufacturing the wavelength conversion material of the present disclosure. That is, the details and preferred aspects of the wavelength conversion material manufactured by the method can be the same as the details and preferred aspects of the wavelength conversion material of the present disclosure.

"Layered Body" The laminated body of the present disclosure is a laminated body for manufacturing the wavelength conversion material, and includes a covering material and a carrier film that is arranged on one side of the covering material and can be peeled from the covering material.

The laminate is used to manufacture the wavelength conversion material of the present disclosure. Since the carrier film is arranged on one side of the covering material, the generation of wrinkles in the manufacturing step of the wavelength conversion material can be suppressed. In addition, by removing the carrier film from the coating material at any time after the manufacturing step, a thin wavelength conversion material can be obtained.

The details and preferred aspects of the coating material and carrier film constituting the laminate are the same as the details and preferred aspects of the coating material and carrier film constituting the wavelength conversion material.

"Backlight Unit" The backlight unit of the present disclosure has a light source and the wavelength conversion material of the present disclosure.

From the viewpoint of improving color reproducibility, the backlight unit is preferably one that has been light sourced with multiple wavelengths. As a preferable aspect, a backlight unit that emits blue light, green light, and red light can be cited. The blue light has a central emission wavelength in the wavelength region of 430 nm to 480 nm, and has a half-value width. Is a luminous intensity peak below 100 nm, the green light has a luminous center wavelength in the wavelength region from 520 nm to 560 nm, and has a luminous intensity peak with a half-value width of 100 nm or less, and the red light has a luminous intensity peak at 600 nm to 560 nm. The 680 nm wavelength region has an emission center wavelength, and has a luminous intensity peak with a half-value width of 100 nm or less. In addition, the half-value width of the luminous intensity peak refers to the peak width at 1/2 height of the peak height.

From the viewpoint of further improving color reproducibility, the emission center wavelength of the blue light emitted by the backlight unit is preferably in the range of 440 nm to 475 nm. From the same viewpoint, the emission center wavelength of the green light emitted by the backlight unit is preferably in the range of 520 nm to 545 nm. In addition, from the same viewpoint, the emission center wavelength of the red light emitted by the backlight unit is preferably in the range of 610 nm to 640 nm.

In addition, from the viewpoint of further improving color reproducibility, the half-value width of each luminous intensity peak of the blue light, green light, and red light emitted by the backlight unit is preferably 80 nm or less, and more preferably 50 nm Hereinafter, it is more preferably 40 nm or less, particularly preferably 30 nm or less, and extremely preferably 25 nm or less.

As the light source of the backlight unit, for example, a light source that emits blue light having an emission center wavelength in a wavelength region of 430 nm to 480 nm can be used. As the light source, for example, a light emitting diode (LED) and a laser can be cited. In the case of using a light source emitting blue light, the wavelength conversion material preferably includes at least a phosphor R emitting red light and a phosphor G emitting green light. In this way, white light can be obtained from the red light and green light emitted from the wavelength conversion material and the blue light transmitted through the wavelength conversion material.

In addition, as the light source of the backlight unit, for example, a light source that emits ultraviolet light having an emission center wavelength in a wavelength region of 300 nm to 430 nm may be used. Examples of the light source include LEDs and lasers. In the case of using a light source that emits ultraviolet light, the wavelength conversion material preferably includes phosphor R and phosphor G, and includes phosphor B that is excited by excitation light and emits blue light. In this way, white light can be obtained from the red light, green light, and blue light emitted from the wavelength conversion material.

The backlight unit of the present disclosure may be an edge light method or a direct type method. An example of a schematic structure of a backlight unit of the edge light method is shown in FIG. 2. The backlight unit 20 shown in Figure 2 includes: a light source 21 emits blue light L _B; light guide plate 22, after the light source 21 emitted from the blue light L _B for emitting light guide; wavelength converting material 10, disposed to face the light guide plate 22 The retroreflective member 23 is arranged opposite to the light guide plate 22 via the wavelength conversion material 10; and the reflective plate 24 is arranged opposite to the wavelength conversion material 10 via the light guide plate 22. Wavelength converting material 10 is part of the blue light L _B as an excitation light to emit red light L _R and the green light L _G, and L _R emits red light and the green light L _G and the blue excitation light does not become light L _B. With the red light L _R , the green light L _G , and the blue light L _{B , white light L W is} emitted from the retroreflective member 23.

"Image Display Device" The image display device of the present disclosure includes the backlight unit of the present disclosure. The image display device is not particularly limited, and for example, a liquid crystal display device can be cited.

An example of the schematic structure of the liquid crystal display device is shown in FIG. 3. The liquid crystal display device 30 shown in FIG. 3 includes a backlight unit 20 and a liquid crystal cell unit 31 arranged opposite to the backlight unit 20. The liquid crystal cell cell 31 has a structure in which the liquid crystal cell 32 is arranged between the polarizing plate 33A and the polarizing plate 33B.

The driving method of the liquid crystal cell 32 is not particularly limited. Examples include: Twisted Nematic (TN) method, Super Twisted Nematic (STN) method, Vertical Alignment (VA) method, and in-plane Switching (In-Plane-Switching, IPS) method, optically compensated birefringence (Optically Compensated Birefringence, OCB) method, etc. [Example]

Hereinafter, the present invention will be described in detail through examples, but the present invention is not limited to these examples.

(Preparation of resin composition for wavelength conversion layer) The resin composition for forming the wavelength conversion layer was prepared by mixing the components shown in Table 1 in the compounding amounts (unit: parts by mass) shown in the table.

As the polyfunctional acrylic compound, tricyclodecane dimethanol diacrylate (manufactured by Shinnakamura Chemical Co., Ltd., A-DCP) was used. As the polyfunctional thiol compound, pentaerythritol tetrakis (3-mercaptopropionate) (manufactured by SC Organic Chemical Co., Ltd., PEMP) was used. As the photopolymerization initiator, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide (manufactured by BASF, IRGACURE TPO) was used. In addition, as the light diffusion material, titanium oxide (manufactured by Chemours, Ti-Pure R-706, volume average particle size 0.36 μm) was used. As the quantum dot phosphor, a Gen3.5QDC dispersion (core/shell: CdSe/ZnS, peak wavelength 532 nm) dispersion (manufactured by Nanosys, Gen3.5 QD Concentrate) was used as Quantum dot phosphor G that emits green light uses Gen3.5QDC dispersion (core/shell: InP/ZnS, peak wavelength 628 nm) dispersion (manufactured by Nanosys, Gen3.5 QD concentrate ( Concentrate)) as a quantum dot phosphor R that emits red light.

[Table 1] ingredient Allocation amount Multifunctional acrylic compound 70.4 Multifunctional thiol compound 23.5 Photopolymerization initiator 1.0 Light diffusion material 0.7 Quantum dot phosphor G 2.5 Quantum dot phosphor R 2.0

(Production of coating material with carrier film) 100 parts by mass of the adhesive, 15.0 parts by mass of the crosslinking agent, 0.1 parts by mass of the catalyst, and 100 parts by mass of the solvent (toluene) were prepared, and stirred with a disperser to prepare an adhesive composition.

As the adhesive, an acrylic adhesive (copolymer of butyl acrylate (BA) and 4-hydroxybutyl acrylate (4HBA), solid content 24% by mass) was used. As the catalyst, a tin-based catalyst (trade name "KS-1200A-1", Kyodo Pharmaceutical Co., Ltd.) was used. As the crosslinking agent, polyfunctional isocyanate (trade name "Coronate (Coronate) HL", solid content 75% by mass, Tosoh Co., Ltd., trimethylolpropane/hexamethylene diisocyanate trimer) was used. The ethyl acetate solution of the adduct, the number of isocyanate groups in a molecule: 3).

The adhesive composition was applied to one side of a PET substrate (A4300, double-sided easy-bonding treatment, Toyobo Co., Ltd., Tg: 73°C) with the thickness shown in Table 2 below, and dried at 100°C 1 Minutes, adjusted to a thickness of 5 μm after drying, and produced a carrier film with an adhesive layer formed on one side. Then, the adhesive layer side of the carrier film was laminated on the covering material (PET substrate with a barrier layer on one side, Dai Nippon Printing Co., Ltd.) of the thickness shown in Table 2 and the surface on which the barrier layer was formed. On the opposite side, make a covering material with a carrier film. The peeling force of the carrier film from the coating material in the prepared coating material with a carrier film is measured by the method. The results are shown in Table 2.

(Preparation of wavelength conversion material) The resin composition for a wavelength conversion layer is applied to the surface of the prepared coating material with a carrier film on the opposite side to the side where the carrier film is arranged to form a coating film. On the coating film, the other covering material with a carrier film was attached to the opposite side of the side where the carrier film was arranged, and irradiated with an ultraviolet irradiation device (Eye Graphics Co., Ltd.) Ultraviolet rays (exposure amount: 1000 mJ/cm ² ) harden the resin composition to produce a wavelength conversion material with a carrier film. The thickness of the wavelength conversion material and the thickness of the wavelength conversion layer in a state where the carrier film is peeled from the wavelength conversion material with a carrier film are shown in Table 2, respectively. At the same time, the wavelength conversion layer of the comparative example was produced in the same manner as in the example except that the covering material of the non-laminated carrier film was used.

(Evaluation of wrinkles) Place the wavelength conversion material (A4 size, 210 mm × 297 mm) with the carrier film peeled off on a flat table, and measure the presence or absence of wrinkles, and the height of the wrinkles when wrinkles are generated (the position where wrinkles are generated) The longest distance between the surface of the wavelength conversion material and the stage). Then, the state of wrinkle generation was evaluated according to the following evaluation criteria.

A: No wrinkles B: The height of the folds is less than 1.5 mm C: The wrinkle height is 1.5 mm or more and less than 3.0 mm D: The wrinkle height is 3.0 mm or more

[Table 2] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Coating material thickness (μm) 15 15 15 15 15 15 Carrier film (substrate) thickness (μm) 80 55 30 45 80 150 Carrier film (adhesive layer) thickness (μm) 5 5 5 5 5 5 Peeling force (N/25 mm) 0.3 0.3 0.3 0.3 0.3 0.3 Wavelength conversion layer thickness (μm) 70 70 70 90 100 100 Wavelength conversion material thickness (μm) 100 100 100 120 130 130 Wrinkles A B C C B A Carrier film thickness A/wavelength conversion layer thickness B 1.21 0.86 0.50 0.56 0.85 1.55 Example 7 Example 8 Comparative example 1 Comparative example 2 Comparative example 3 Coating material thickness (μm) 25 25 15 110 75 Carrier film (substrate) thickness (μm) 80 80 - - - Carrier film (adhesive layer) thickness (μm) 5 5 - - - Peeling force (N/25 mm) 0.3 0.3 - - - Wavelength conversion layer thickness (μm) 100 70 70 110 80 Wavelength conversion material thickness (μm) 150 120 100 330 220 Wrinkles B A D A B Carrier film thickness A/wavelength conversion layer thickness B 0.85 1.21 - - -

As shown in Table 2, in the wavelength conversion materials of Examples 1 to 8 in which a coating material with a carrier film is used as the coating material, even in a state where the thickness of the wavelength conversion material is thin (100 μm), The generation of wrinkles is also suppressed. In addition, as shown in the results of Examples 1 to 3, the thicker the carrier film, the more effectively the generation of wrinkles is suppressed. Furthermore, comparing Example 1 and Example 5 where the thickness of the carrier film is the same but the thickness of the wavelength conversion layer is different, the ratio (A/B) of the thickness A of the carrier film to the thickness B of the wavelength conversion layer is larger. Compared with Example 5 of Example 1, the generation of wrinkles is suppressed. Similarly, comparing Example 7 with Example 8 where the thickness of the carrier film is the same but the thickness of the wavelength conversion layer is different, the ratio (A/B) of the thickness A of the carrier film to the thickness B of the wavelength conversion layer is higher. Compared with Example 7, the large Example 8 has suppressed the generation of wrinkles. In the wavelength conversion material of Comparative Example 1 that used the covering material of the non-laminated carrier film and formed the same thickness as the examples, the generation of wrinkles was remarkable. From the results of Comparative Examples 1 to 3, it can be seen that it is difficult to achieve suppression of wrinkles and reduction in the thickness of the wavelength conversion material without using a carrier film.

The disclosure of International Application No. PCT/JP2019/031689 is incorporated into this specification in its entirety by reference. All documents, patent applications, and technical specifications described in this specification are to the same extent as the case where each document, patent application, and technical specifications are specifically and separately described and incorporated by reference, and are incorporated into this specification by reference in.

10: Wavelength conversion material 11: Wavelength conversion layer 12A, 12B: Cladding material 13A, 13B: Carrier film 20: Backlight unit 21: Light source 22: Light guide plate 23: Retroreflective member 24: Reflective plate 30: Liquid crystal display device 31: Liquid crystal cell unit 32: Liquid crystal cell 33A, 33B: Polarizing plate L _B : Blue light L _G : Green light L _R : Red light L _W : White light

Fig. 1 is a schematic cross-sectional view showing an example of a schematic structure of a wavelength conversion material. Fig. 2 is a diagram showing an example of a schematic configuration of a backlight unit. Fig. 3 is a diagram showing an example of a schematic configuration of a liquid crystal display device.

Claims (18)

A wavelength conversion material, including: The wavelength conversion layer includes a phosphor and a cured resin; and The cladding material is arranged on both sides of the wavelength conversion layer, The wavelength conversion material is in a state where a carrier film that can be peeled from the covering material is arranged on the outer surface of at least one of the covering materials. The wavelength conversion material according to claim 1, wherein the ratio of the thickness A of the carrier film to the thickness B of the wavelength conversion layer is 0.4 or more. The wavelength conversion material according to claim 1 or 2, wherein the Tg of the carrier film is 50°C or higher. The wavelength conversion material according to any one of claims 1 to 3, wherein the peel force of the carrier film from the coating material measured under the condition of a peeling speed of 300 mm/min is 0.7 N/25 mm the following. The wavelength conversion material according to any one of claims 1 to 4, wherein the thickness of the coating material is 25 μm or less. The wavelength conversion material according to any one of claims 1 to 5, wherein the thickness of the wavelength conversion material in a state where the carrier film is not arranged is 150 μm or less. The wavelength conversion material according to any one of claims 1 to 6, wherein the thickness of the carrier film is 30 μm to 200 μm. The wavelength conversion material according to any one of claims 1 to 7, wherein the wrinkle height in a state where the carrier film is not arranged is less than 3.0 mm. A wavelength conversion material, including: The wavelength conversion layer includes a phosphor and a cured resin; and The cladding material is arranged on both sides of the wavelength conversion layer, The total thickness of the wavelength conversion layer and the coating material is 150 μm or less. The wavelength conversion material according to claim 9, wherein the wrinkle height is less than 3.0 mm. The wavelength conversion material according to any one of claims 1 to 10, which is in a film shape. The wavelength conversion material according to any one of claims 1 to 11, which is used for image display. The wavelength conversion material according to any one of claims 1 to 12, wherein the phosphor includes a quantum dot phosphor. The wavelength conversion material according to claim 13, wherein the quantum dot phosphor includes a compound containing at least one of Cd or In. A method for manufacturing a wavelength conversion material, including: The step of preparing a laminate, the laminate including a resin composition layer, a coating material, and a carrier film, the resin composition layer including a phosphor and a resin, and the coating material is disposed on the resin composition layer On both sides, the carrier film is disposed on the outer surface of at least one of the covering materials and can be peeled off from the covering material; and The step of hardening the resin composition layer of the laminate. A laminate for manufacturing the wavelength conversion material according to any one of claims 1 to 14, The laminate includes a covering material and a carrier film that is arranged on one side of the covering material and can be peeled from the covering material. A backlight unit includes the wavelength conversion material according to any one of claims 1 to 14 and a light source. An image display device includes the backlight unit according to claim 17.

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