WO2021106556A1

WO2021106556A1 - Wavelength converting member and method for manufacturing same, back-light unit, and image display device

Info

Publication number: WO2021106556A1
Application number: PCT/JP2020/041943
Authority: WO
Inventors: 紀一福原; 里奈伊豆
Original assignee: 昭和電工マテリアルズ株式会社
Priority date: 2019-11-29
Filing date: 2020-11-10
Publication date: 2021-06-03

Abstract

This wavelength converting member comprises: a wavelength converting layer including a fluorescent material; a covering material disposed on one or both main surfaces of the wavelength converting layer; and a protective layer which is disposed on the side surface of the wavelength converting layer and which includes a metal oxide layer and a resin layer.

Description

Wavelength conversion member and its manufacturing method, backlight unit, and image display device

The present disclosure relates to a wavelength conversion member and its manufacturing method, a backlight unit, and an image display device.

A backlight unit is provided in an image display device such as a liquid crystal display device. The backlight unit includes a wavelength conversion member including a phosphor that emits light from a light source. For example, when a wavelength conversion member including a quantum dot phosphor that emits red light and a quantum dot phosphor that emits green light is used, when the wavelength conversion member is irradiated with blue light as excitation light, the quantum dot phosphor White light can be obtained from the red light and green light emitted from the light and the blue light transmitted through the wavelength conversion member.

The wavelength conversion member containing a phosphor usually has a cured product obtained by curing a curable composition containing a phosphor. Further, in the wavelength conversion member containing a phosphor, at least a part of the cured product containing the phosphor may be covered with a coating material. For example, in the case of a film-shaped wavelength conversion member, a barrier film having a barrier property against oxygen may be provided on one side or both sides of the cured product containing a phosphor.

On the other hand, even when the barrier film is provided on one side or both sides of the cured product containing the phosphor, oxygen enters from the side surface not protected by the barrier film, which causes a decrease in brightness at the end of the wavelength conversion member. It happened to be. As a method of suppressing deterioration of the phosphor due to the intrusion of oxygen or the like from the end face, Patent Document 1 includes an end face sealing layer covering the end face of the wavelength conversion layer including the gas barrier layer, and the end face sealing layer is the first. A wavelength conversion laminated film containing a metal layer, a resin layer, and a second metal layer in this order has been proposed.

JP-A-2017-78773

However, the wavelength conversion laminated film described in Patent Document 1 requires steps such as metal sputtering, resin layer formation, and electroless plating at the end of the wavelength conversion layer, which is complicated. In view of this situation, a method of suppressing deterioration of the phosphor at the end of the wavelength conversion member by another novel configuration has been searched for.

An object of the present disclosure is to provide a novel wavelength conversion member capable of suppressing a decrease in brightness at an end, a method for manufacturing the same, and a backlight unit and an image display device using the wavelength conversion member.

Means for solving the above problems include the following aspects.
<1> A wavelength conversion layer containing a phosphor and
A coating material arranged on one main surface or both main surfaces of the wavelength conversion layer,
A protective layer including a metal oxide layer and a resin layer arranged on the side surface of the wavelength conversion layer, and
Wavelength conversion member having.
<2> The wavelength conversion member according to <1>, wherein the resin layer is arranged outside the metal oxide layer on the side surface of the wavelength conversion layer.
<3> The wavelength conversion member according to <1> or <2>, wherein the resin layer forms the outermost surface on the side surface of the wavelength conversion layer.
<4> The wavelength conversion member according to any one of <1> to <3>, wherein the resin layer contains a poly (meth) acrylic acid ester.
<5> The protective layer covers the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer, <1> to <4. > The wavelength conversion member according to any one of the items.
<6> A backlight unit including the wavelength conversion member according to any one of <1> to <5> and a light source.
<7> An image display device including the backlight unit according to <6>.
<8> A metal oxide layer and a resin are formed on the side surfaces of a laminate having a wavelength conversion layer containing a phosphor and a coating material arranged on one main surface or both main surfaces of the wavelength conversion layer. A method for manufacturing a wavelength conversion member, which comprises a step of forming a protective layer including a layer.
<9> The method for manufacturing a wavelength conversion member according to <8>, wherein the metal oxide layer is formed by an atomic layer deposition method.
<10> The wavelength conversion according to <8> or <9>, wherein the step of forming the protective layer includes a step of forming the metal oxide layer and a step of forming the resin layer in this order. Manufacturing method of parts.
<11> The method for producing a wavelength conversion member according to any one of <8> to <10>, wherein the resin layer contains a poly (meth) acrylic acid ester.
<12> The method for manufacturing a wavelength conversion member according to any one of <8> to <11>, wherein the protective layer is formed so as to cover the outer peripheral surface of the laminated body.

According to the present disclosure, a novel wavelength conversion member capable of suppressing a decrease in brightness at an end portion and a method for manufacturing the same, and a backlight unit and an image display device using the wavelength conversion member are provided.

It is a schematic cross-sectional view which shows an example of the schematic structure of the wavelength conversion member. It is a schematic cross-sectional view which shows an example of the schematic structure of the wavelength conversion member. It is a figure which shows an example of the schematic structure of the backlight unit. It is a figure which shows an example of the schematic structure of the liquid crystal display device.

Hereinafter, a mode for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified. The same applies to the numerical values and their ranges, and does not limit the present invention.

In the present disclosure, the term "process" includes not only a process independent of other processes but also the process if the purpose of the process is achieved even if the process cannot be clearly distinguished from the other process. ..
The numerical range indicated by using "-" in the present disclosure includes the numerical values before and after "-" as the minimum value and the maximum value, respectively.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. .. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present disclosure, each component may contain a plurality of applicable substances. When a plurality of substances corresponding to each component are present in the composition, the content or content of each component is the total content or content of the plurality of substances present in the composition unless otherwise specified. Means quantity.
In the present disclosure, a plurality of types of particles corresponding to each component may be contained. When a plurality of particles corresponding to each component are present in the composition, the particle size of each component means a value for a mixture of the plurality of particles present in the composition unless otherwise specified.
In the present disclosure, the term "layer" or "membrane" refers to only a part of the region, in addition to the case where the layer or the membrane is formed in the entire region when the region where the layer or the membrane exists is observed. The case where it is formed is also included.
In the present disclosure, the term "laminated" refers to stacking layers, and two or more layers may be bonded or the two or more layers may be removable.
In the present disclosure, "(meth) acryloyl" means at least one of acryloyl and methacrylic, "(meth) acrylic" means at least one of acrylic and methacrylic, and "(meth) acrylate" means at least one of acrylate and methacrylate. Means, "(meth) allyl" represents at least one of allyl and methacrylic.
When the embodiment is described in the present disclosure with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Further, the size of the members in each figure is conceptual, and the relative relationship between the sizes of the members is not limited to this. Further, in each drawing, members having substantially the same function may be given the same reference numerals in all drawings, and duplicate description may be omitted.

≪Wavelength conversion member≫
The wavelength conversion member according to the embodiment of the present disclosure includes a wavelength conversion layer containing a phosphor, a coating material arranged on one main surface or both main surfaces of the wavelength conversion layer, and the wavelength conversion layer. It has a protective layer including a metal oxide layer and a resin layer, which is arranged on the side surface of the above. In the wavelength conversion member of the present embodiment, since the side surface of the wavelength conversion layer is protected by the protective layer, it is possible to suppress a decrease in brightness at the end portion. Further, in one aspect, the wavelength conversion member of the present embodiment tends to be excellent in moisture and heat resistance. Hereinafter, each essential or optional member included in the wavelength conversion member will be described in detail.

<Wavelength conversion layer>
The wavelength conversion layer contains a phosphor. The wavelength conversion layer may further contain a cured resin product, or may have a phosphor contained (encapsulated) in the cured resin product. Further, the wavelength conversion layer may further contain a light diffusing material.

[Phosphor]
The wavelength conversion layer contains a phosphor that emits light when irradiated with light from a light source. The type of phosphor is not particularly limited, and examples thereof include an organic phosphor and an inorganic phosphor.
Examples of the organic phosphor include a naphthalimide compound and a perylene compound.
Examples of the inorganic phosphor include Y ₃ O ₃ : Eu, YVO ₄ : Eu, Y ₂ O ₂ : Eu, 3.5 MgO / 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 : Green luminescent inorganic phosphors such as Ge · Tb, LaOBr: Tb · Tm, La ₂ O ₂ S: Tb, 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 light emitting inorganic phosphors, quantum dot phosphors and the like can be mentioned.

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

Specific examples of the II-VI group compounds include CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSte, ZnSeS, ZnSeTe, ZnSte, HgSeS, ZnS. , CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSeTe
Specific examples of Group III-V compounds include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, COLP, PLGAs, VMwareSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb , AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInNSb, GaInPAs, GaInPSb, InNAAl
Specific examples of the IV-VI group compounds include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSte, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbSe ..
Specific examples of the Group IV compound 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, it is possible to further improve the quantum efficiency of the quantum dot phosphor. Examples of the combination of core and shell (core / shell) include CdSe / ZnS, InP / ZnS, PbSe / PbS, CdSe / CdS, CdTe / CdS, and CdTe / ZnS.

Further, the quantum dot phosphor may have a so-called core multi-shell structure in which the shell has a multi-layer structure. By stacking one or more layers of shells with a narrow bandgap on a core with a wide bandgap, and further stacking a shell with a wide bandgap on top of this shell, the quantum efficiency of the quantum dot phosphor can be further improved. Is possible.

When the wavelength conversion layer contains a quantum dot phosphor, the wavelength conversion layer may contain one kind of quantum dot phosphor alone, or may contain two or more kinds of quantum dot phosphors in combination. May be good. Examples of a mode in which two or more types of quantum dot phosphors are contained in combination include a mode in which two or more types of quantum dot phosphors having different components but the same average particle size are contained, and a mode in which components having different average particle sizes are contained. Examples thereof include an embodiment containing two or more types of quantum dot phosphors, and an embodiment containing two or more types of quantum dot phosphors having different components and average particle diameters. The emission center wavelength of the quantum dot phosphor can be changed by changing at least one selected from the group consisting of the components of the quantum dot phosphor and the average particle size.

For example, the wavelength conversion layer includes a quantum dot phosphor G having an emission center wavelength in the green wavelength region of 520 nm to 560 nm and a quantum dot phosphor R having an emission center wavelength in the red wavelength region of 600 nm to 680 nm. It may be contained. When the wavelength conversion layer containing the quantum dot phosphor G and the quantum dot phosphor R is irradiated with excitation light in the blue wavelength range of 430 nm to 480 nm, the quantum dot phosphor G and the quantum dot phosphor R are green, respectively. Light and red light are emitted. As a result, white light can be obtained by the green light and red light emitted from the quantum dot phosphor G and the quantum dot phosphor R and the blue light transmitted through the cured product.

The content of the phosphor in the wavelength conversion layer is preferably, for example, 0.01% by mass to 1.0% by mass, and 0.05% by mass to 0.5% by mass, based on the entire wavelength conversion layer. Is more preferable, and 0.1% by mass to 0.5% by mass is further preferable. When the content of the phosphor is 0.01% by mass or more with respect to the entire wavelength conversion layer, a sufficient wavelength conversion function tends to be obtained, and when the content of the phosphor is 0.01% by mass or less. , The aggregation of phosphors tends to be suppressed.

[Resin cured product]
The wavelength conversion layer may further contain a cured resin product. The wavelength conversion layer may be a layer in which the above-mentioned phosphor is contained in the cured resin product.

The cured resin product preferably contains a sulfide structure from the viewpoint of adhesion to other members (coating material, etc.) of the cured resin product and suppression of wrinkles due to volume shrinkage during curing. The cured resin composition containing a sulfide structure is obtained by curing a resin composition containing, for example, a thiol compound described later and a polymerizable compound having a carbon-carbon double bond that causes an enthiol reaction with a thiol group of the thiol compound. Obtainable.

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

From the viewpoint of suppressing contact between the phosphor and oxygen, the cured resin product preferably contains an alkyleneoxy group. When the cured resin product contains an alkyleneoxy group, the polarity of the cured resin product increases, and non-polar oxygen tends to be difficult to dissolve in the components in the cured product. In addition, the flexibility of the cured resin product tends to increase and the adhesion to the coating material tends to improve.

The cured resin product containing an alkyleneoxy group can be obtained, for example, by curing a resin composition containing a polymerizable compound having an alkyleneoxy group, which will be described later.

-Resin composition-
The wavelength conversion layer may be a cured product of a composition containing a phosphor, a polymerizable compound, and a photopolymerization initiator (hereinafter, also simply referred to as a resin composition). The resin composition may contain a phosphor, a thiol compound, at least one selected from the group consisting of a (meth) acrylic compound and a (meth) allyl compound, and a photopolymerization initiator. The resin composition may optionally contain other components. Hereinafter, each component of the resin composition will be described in detail.

(Phosphor)
The resin composition contains a phosphor. The details of the phosphor are as described above.

When a quantum dot phosphor is used as the phosphor, the quantum dot phosphor may be used in the state of a quantum dot phosphor dispersion liquid dispersed in a dispersion medium. Examples of the dispersion medium for dispersing the quantum dot phosphor include various organic solvents, silicone compounds, and monofunctional (meth) acrylate compounds. The quantum dots may be used in the state of a quantum dot phosphor dispersion liquid by using a dispersant, if necessary.

The organic solvent that can be used as the dispersion medium is not particularly limited as long as precipitation and aggregation of the quantum dot phosphor are not confirmed, and acetonitrile, methanol, ethanol, acetone, 1-propanol, ethyl acetate, butyl acetate, toluene, hexane and the like are not particularly limited. Can be mentioned.

Silicone compounds that can be used as a dispersion medium include straight silicone oils such as dimethyl silicone oil, methylphenyl silicone oil, and methylhydrogen silicone oil; amino-modified silicone oil, epoxy-modified silicone oil, carboxy-modified silicone oil, and carbinol-modified silicone. Oil, mercapto-modified silicone oil, heterogeneous functional group-modified silicone oil, polyether-modified silicone oil, methylstyryl-modified silicone oil, hydrophilic special-modified silicone oil, higher alkoxy-modified silicone oil, higher fatty acid-modified silicone oil, fluorine-modified silicone oil, etc. Modified silicone oil and the like.

The monofunctional (meth) acrylate compound that can be used as a dispersion medium is not particularly limited as long as it is liquid at 25 ° C., and a monofunctional (meth) acrylate compound having an alicyclic structure (preferably isobornyl (meth)). ) Acrylate and dicyclopentanyl (meth) acrylate), methoxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, ethoxylated o-phenylphenol (meth) acrylate and the like.

Examples of the dispersant used as needed include polyether amine (trade name: JEFFAMINE (registered trademark) M-1000, HUNTSMAN), oleic acid and the like.

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

The content of the quantum dot phosphor dispersion liquid in the resin composition is the total amount of the resin composition when the mass-based ratio of the quantum dot phosphor to the quantum dot phosphor dispersion liquid is 1% by mass to 20% by mass. On the other hand, for example, it is preferably 1% by mass to 10% by mass, more preferably 4% by mass to 10% by mass, and further preferably 4% by mass to 7% by mass.

The content of the quantum dot phosphor in the resin composition is preferably, for example, 0.01% by mass to 1.0% by mass, preferably 0.05% by mass or more, based on the total amount of the resin composition. It is more preferably 0.5% by mass, and further preferably 0.1% by mass to 0.5% by mass. When the content of the quantum dot phosphor is 0.01% by mass or more, sufficient emission intensity tends to be obtained when the cured product is irradiated with excitation light, and the content of the quantum dot phosphor is 1.0. When it is mass% or less, the aggregation of the quantum dot phosphor tends 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 a thiol compound, a (meth) acrylic compound, and a (meth) allyl compound. The (meth) allyl compound means a compound having a (meth) allyl group in the molecule, and the (meth) acrylic compound means a compound having a (meth) acryloyl group in the molecule. Compounds having both a (meth) allyl group and a (meth) acryloyl group in the molecule shall be classified as (meth) allyl compounds for convenience.

From the viewpoint of adhesion of the wavelength conversion layer to other members (coating material, etc.), the resin composition is selected from the group consisting of a thiol compound, a (meth) acrylic compound and a (meth) allyl compound as a polymerizable compound at least. 1 type and may be included. A cured product obtained by curing a resin composition containing a thiol compound as a polymerizable compound and at least one selected from the group consisting of a (meth) acrylic compound and a (meth) allyl compound has a thiol group and ( A sulfide structure (RSR', R and R'represents an organic group) formed by an enthiol reaction with a carbon-carbon double bond of a (meth) acryloyl group or a (meth) allyl group. Including. As a result, the adhesion between the wavelength conversion layer and the coating material tends to be improved. Further, the optical characteristics of the wavelength conversion layer tend to be further improved.

Hereinafter, the thiol compound, the (meth) acrylic compound, and the (meth) allyl compound that can be used as the polymerizable compound will be described in detail.

A. Thiol compound The thiol compound may be a monofunctional thiol compound having one thiol group in one molecule, or a polyfunctional thiol compound having two or more thiol groups in one molecule. The thiol compound contained in the resin composition may be only one kind or two or more kinds.

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

Specific examples of the monofunctional thiol compound include hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanthiol, 1-decanethiol, 3-mercaptopropionic acid, methyl mercaptopropionate, methoxybutyl mercaptopropionate, and the like. Examples thereof include octyl mercaptopropionate, tridecyl mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, n-octyl-3-mercaptopropionate and the like.

Specific examples of the polyfunctional thiol compound include ethylene glycol bis (3-mercaptopropionate), diethylene glycol bis (3-mercaptopropionate), tetraethylene glycol bis (3-mercaptopropionate), 1,2-. Propropylene glycol bis (3-mercaptopropionate), diethylene glycol bis (3-mercaptobutyrate), 1,4-butanediol bis (3-mercaptopropionate), 1,4-butanediol bis (3-mercaptobutyrate) Rate), 1,8-octanediol bis (3-mercaptopropionate), 1,8-octanediol bis (3-mercaptobutyrate), hexanediol bisthioglycolate, trimethylolpropanthris (3-mercaptopro) Pionate), trimethylolpropanetris (3-mercaptobutyrate), trimethylolpropanetris (3-mercaptoisobutyrate), trimethylolpropanetris (2-mercaptoisobutyrate), trimethylolpropanetristhioglycolate, Tris-[(3-mercaptopropionyloxy) -ethyl] -isocyanurate, trimethyl ethanetris (3-mercaptobutyrate), pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate) ), Pentaerythritol tetrakis (3-mercaptoisobutyrate), pentaerythritol tetrakis (2-mercaptoisobutyrate), dipentaerythritol hexakis (3-mercaptopropionate), dipentaerythritol hexakis (2-mercaptopro) Pionate), dipentaerythritol hexakis (3-mercaptobutyrate), dipentaerythritol hexakis (3-mercaptoisobutyrate), dipentaerythritol hexakis (2-mercaptoisobutyrate), pentaerythritol tetrakisthioglycol Rate, dipentaerythritol hexaxthioglycolate and the like can be mentioned.

From the viewpoint of further improving the adhesion between the wavelength conversion layer and the coating material, heat resistance, and moist heat resistance, the thiol compound preferably contains a polyfunctional 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 further preferably 100% by mass.

The thiol compound may be in the state of a thioether oligomer that has reacted with the (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, the content of the thiol compound in the resin composition is preferably, for example, 5% by mass to 80% by mass, and 15% by mass, based on the total amount of the resin composition. It is more preferably to 70% by mass, and further preferably 20% by mass to 60% by mass.
When the content of the thiol compound is 5% by mass or more with respect to the total amount of the resin composition, the adhesion of the wavelength conversion layer to the coating material tends to be further improved, and the content of the thiol compound is the resin composition. When it is 80% by mass or less with respect to the total amount, the heat resistance and the moist heat resistance of the wavelength conversion layer tend to be further improved.

B. (Meta) Acrylic Compound The (meth) acrylic compound may be a monofunctional (meth) acrylic compound having one (meth) acryloyl group in one molecule, and two or more (meth) acrylic compounds in one molecule. It may be a polyfunctional (meth) acrylic compound having an acryloyl group. The (meth) acrylic compound contained in the resin composition may be one kind or two or more kinds.

Specific examples of the monofunctional (meth) acrylic compound include (meth) acrylic acid; methyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isononyl (meth). ) Alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms such as acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate; benzyl (meth) acrylate, phenoxyethyl ( A (meth) acrylate compound having an aromatic ring such as a meta) acrylate; an alkoxyalkyl (meth) acrylate such as butoxyethyl (meth) acrylate; an aminoalkyl (meth) acrylate 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) acrylate, octaethylene glycol monomethyl ether (meth) acrylate, nona Polyalkylene glycol monoalkyl ether (meth) such as ethylene glycol monomethyl ether (meth) acrylate, dipropylene glycol monomethyl ether (meth) acrylate, heptapropylene glycol monomethyl ether (meth) acrylate, and tetraethylene glycol monoethyl ether (meth) acrylate. Acrylate: Polyalkylene glycol monoaryl ether (meth) acrylate such as hexaethylene glycol monophenyl ether (meth) acrylate; cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate, methylene oxide-added cyclo (Meta) acrylate compound having an alicyclic structure such as decatorien (meth) acrylate; (meth) acrylate compound having a heterocycle such as (meth) acryloylmorpholine and tetrahydrofurfuryl (meth) acrylate; heptadecafluorodecyl (meth) ) Alkyl fluoride (meth) acrylates such as acrylates; 2-hydroxyethyl (meth) acrylates, 3-hydroxypropyl (meth) acrylates, 4-hydroxybutyl (meth) acrylates, trietylene Nglycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) acrylate, octapropylene glycol mono (meth) acrylate and other (meth) acrylate compounds having hydroxyl groups; glycidyl (meth) acrylate A (meth) acrylate compound having a glycidyl group such as 2- (2- (meth) acryloyloxyethyloxy) ethyl isocyanate, a (meth) acrylate compound having an isocyanate group such as 2- (meth) acryloyloxyethyl isocyanate; tetra Polyalkylene glycol mono (meth) acrylates such as ethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) acrylate, octapropylene glycol mono (meth) acrylate; (meth) acrylamide, N, N-dimethyl (meth) acrylamide. , N-Isopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide and other (meth) acrylamide compounds; Be done.

Specific examples of the polyfunctional (meth) acrylic compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol di (meth) acrylate. Polyalkylene glycol di (meth) acrylate; Polyalkylene glycol di (meth) acrylate such as polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate; Trimethylol propantri (meth) acrylate, Trimethylol propantri with ethylene oxide (meth) Tri (meth) acrylate compounds such as meth) acrylate and tris (2-acryloyloxyethyl) isocyanurate; ethylene oxide-added pentaerythritol tetra (meth) acrylate, trimethylolpropanetetra (meth) acrylate, pentaerythritol tetra (meth) acrylate and the like. Tetra (meth) acrylate compounds; tricyclodecanedimethanol di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, 1,3-adamantan dimethanol di (meth) acrylate, hydrogenated bisphenol A (poly) ethoxydi ( Meta) acrylate, hydrogenated bisphenol A (poly) propoxydi (meth) acrylate, hydrogenated bisphenol F (poly) ethoxydi (meth) acrylate, hydrogenated bisphenol F (poly) propoxydi (meth) acrylate, hydrogenated bisphenol S (poly) Examples thereof include (meth) acrylate compounds having an alicyclic structure such as ethoxydi (meth) acrylate and hydrogenated bisphenol S (poly) propoxydi (meth) acrylate.

The (meth) acrylic compound is preferably a (meth) acrylate compound having an alicyclic structure or an aromatic ring structure from the viewpoint of further improving the heat resistance and moisture heat resistance of the cured product. Examples of the alicyclic structure or aromatic ring structure include an isobornyl skeleton, a tricyclodecane skeleton, and a bisphenol skeleton.

The (meth) acrylic compound may have an alkyleneoxy group or may be a bifunctional (meth) acrylic compound having an alkyleneoxy group.

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

The alkyleneoxy group-containing compound may be a polyalkyleneoxy group-containing compound having a polyalkyleneoxy group containing a plurality of alkyleneoxy groups.

When the (meth) acrylic compound has an alkyleneoxy group, the number of alkyleneoxy groups in one molecule is preferably 2 to 30, more preferably 2 to 20, and 3 to 20. It is more preferably 10 pieces, and particularly preferably 3 to 5 pieces.

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

Specific examples of the (meth) acrylic compound having an alkyleneoxy group include alkoxyalkyl (meth) acrylates such as butoxyethyl (meth) acrylates; diethylene glycol monoethyl ether (meth) acrylates, triethylene glycol monobutyl ether (meth) acrylates, and the like. Tetraethylene glycol monomethyl ether (meth) acrylate, hexaethylene glycol monomethyl ether (meth) acrylate, octaethylene glycol monomethyl ether (meth) acrylate, nonaethylene glycol monomethyl ether (meth) acrylate, dipropylene glycol monomethyl ether (meth) acrylate, Polyalkylene glycol monoalkyl ether (meth) acrylates such as heptapropylene glycol monomethyl ether (meth) acrylates and tetraethylene glycol monoethyl ether (meth) acrylates; polyalkylene glycol monoaryls such as hexaethylene glycol monophenyl ether (meth) acrylates. Ether (meth) acrylate; (meth) acrylate compound having a heterocycle such as tetrahydrofurfuryl (meth) acrylate; triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) (Meta) acrylate compound having a hydroxyl group such as acrylate and octapropylene glycol mono (meth) acrylate; (meth) acrylate compound having a glycidyl group such as glycidyl (meth) acrylate; polyethylene glycol di (meth) acrylate, polypropylene glycol di ( Polyalkylene glycol di (meth) acrylates such as meta) acrylates; tri (meth) acrylate compounds such as ethylene oxide-added trimethylol propantri (meth) acrylates; tetra (meth) acrylate compounds such as ethylene oxide-added pentaerythritol tetra (meth) acrylates. Examples thereof include bisphenol type di (meth) acrylate compounds such as ethoxylated bisphenol A type di (meth) acrylate, propoxylated bisphenol A type di (meth) acrylate, and propoxylated ethoxylated bisphenol A type di (meth) acrylate; ..
As the alkyleneoxy group-containing compound, ethoxylated bisphenol A type di (meth) acrylate, propoxylated bisphenol A type di (meth) acrylate and propoxylated ethoxylated bisphenol A type di (meth) acrylate are preferable, and ethoxylated bisphenol A-type di (meth) acrylate is more preferable.

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

C. (Meta) Allyl Compound The (meth) allyl compound may be a monofunctional (meth) allyl compound having one (meth) allyl group in one molecule, and two or more (meth) allyl compounds in one molecule. It may be a polyfunctional (meth) allyl compound having an allyl group. The (meth) allyl compound contained in the resin composition may be only one kind or two or more kinds.

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

Specific examples of the monofunctional (meth) allyl compound include (meth) allyl acetate, (meth) allyl n-propionate, (meth) allyl benzoate, (meth) allyl phenyl acetate, (meth) allyl phenoxy acetate, and (meth). Examples thereof include allyl methyl ether and (meth) allyl glycidyl ether.

Specific examples of the polyfunctional (meth) allyl compound include di (meth) allyl benzenedicarboxylate, di (meth) allyl cyclohexanedicarboxylate, di (meth) allylmaleate, di (meth) allyl adipate, and di (meth). Allyl phthalate, di (meth) allyl isophthalate, di (meth) allyl terephthalate, glycerin di (meth) allyl ether, trimethylpropandi (meth) allyl ether, pentaerythritol di (meth) allyl ether, 1,3-di (Meta) allyl-5-glycidyl isocyanurate, tri (meth) allyl cyanurate, tri (meth) allyl isocyanurate, tri (meth) allyl trimellitate, tetra (meth) allyl pyromeritate, 1,3,4 , 6-Tetra (meth) allyl glycol uryl, 1,3,4,6-tetra (meth) allyl-3a-methylglycoluryl, 1,3,4,6-tetra (meth) allyl-3a, 6a-dimethyl Glycol-uryl and the like can be mentioned.

Examples of the (meth) allyl compound include compounds having an isocyanurate skeleton such as tri (meth) allyl isocyanurate, tri (meth) allyl cyanurate, and benzenedicarboxylic acid di (meth) from the viewpoint of heat resistance and moisture heat resistance of the cured product. ) At least one selected from the group consisting of allyl and di (meth) allyl cyclohexanedicarboxylic acid is preferable, a compound having an isocyanurate skeleton is more preferable, and tri (meth) allyl isocyanurate is further preferable.

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

In some embodiments, 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 as a thiol compound and a (meth) allyl compound and a quantum dot phosphor is used as the phosphor, the quantum dot phosphor is a dispersion liquid dispersed in a silicone compound as a dispersion medium. It is preferably in a state.

In certain embodiments, the polymerizable compound is a thiol compound that is not in the form of a thioether oligomer, and a (meth) acrylic compound (preferably a polyfunctional (meth) acrylic compound, more preferably a bifunctional (meth) acrylic compound). May be included.

When the polymerizable compound contains a thiol compound that is not in the state of a thioether oligomer and a (meth) acrylic compound and a quantum dot phosphor is used as the phosphor, the quantum dot phosphor is used as the dispersion medium (meth). It is preferably in the state of a dispersion liquid dispersed in an acrylic compound, preferably a monofunctional (meth) acrylic compound, and more preferably isobornyl (meth) acrylate.

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

Specific examples of the photopolymerization initiator include benzophenone, N, N'-tetraalkyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1, 4,4'-bis (dimethylamino) benzophenone (also referred to as "Michler ketone"), 4,4'-bis (Diethylamino) benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 1-hydroxycyclohexylphenylketone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4- (4-) Aromatic ketone compounds such as (2-hydroxyethoxy) -phenyl) -2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one; alkyl Kinone compounds such as anthraquinone and phenanthrenquinone; 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-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl)- 2,4,5-Triarylimidazole dimer such as 4,5-diphenylimidazole dimer; aclysine derivative such as 9-phenylaclysine, 1,7- (9,9'-acrydinyl) heptane; 1,2 -Octanedione 1- [4- (Phenylthio) -2- (O-benzoyloxime)], Ethanone 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- Oxyme ester compounds such as (O-acetyloxime); coumarin compounds such as 7-diethylamino-4-methylkumarin; thioxanthone compounds such as 2,4-diethylthioxanthone; 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2,4,6-trimethylbenzoyl Acylphosphine oxide compounds such as -phenyl-ethoxy-phosphine oxide; and the like. The resin composition may contain one kind of photopolymerization initiator alone, or may contain two or more kinds of photopolymerization initiators in combination.

As the photopolymerization initiator, at least one selected from the group consisting of an acylphosphine oxide compound, an aromatic ketone compound, and an oxime ester compound is preferable from the viewpoint of curability, and from the acylphosphine oxide compound and the aromatic ketone compound. At least one selected from the above group is more preferable, and an acylphosphine oxide compound is further preferable.

The content of the photopolymerization initiator in the resin composition is preferably, for example, 0.1% by mass to 5% by mass, preferably 0.1% by mass to 3% by mass, based on the total amount of the resin composition. It is more preferably 0.1% by mass to 1.5% by mass. When the content of the photopolymerization initiator is 0.1% by mass or more, the sensitivity of the resin composition tends to be sufficient, and when the content of the photopolymerization initiator is 5% by mass or less, the resin The influence on the hue of the composition and the decrease in storage stability tend to be suppressed.

(Light diffuser)
From the viewpoint of improving the light conversion efficiency, the resin composition may further contain a light diffusing material. Specific examples of the light diffusing material include titanium oxide, barium sulfate, zinc oxide, calcium carbonate and the like. Among these, titanium oxide is preferable from the viewpoint of light scattering efficiency. The titanium oxide may be rutile-type titanium oxide or anatase-type titanium oxide, and is preferably rutile-type titanium oxide.

The average particle size of the light diffusing material is preferably 0.1 μm to 1 μm, more preferably 0.2 μm to 0.8 μm, and even more preferably 0.2 μm to 0.5 μm.
In the present disclosure, the average particle size of the light diffusing material can be measured as follows.
When the light diffusing material is contained in the resin composition, the extracted light diffusing material is dispersed in purified water containing a surfactant to obtain a dispersion liquid. In the volume-based particle size distribution measured by a laser diffraction type particle size distribution measuring device (for example, Shimadzu Corporation, SALD-3000J) using this dispersion, the value when the integration from the small diameter side is 50% ( The median diameter (D50)) is defined as the average particle size of the light diffusing material. As a method for extracting the light diffusing material from the resin composition, for example, the resin composition can be obtained by diluting the resin composition with a liquid medium, precipitating the light diffusing material by centrifugation or the like, and distributing the light diffusing material.
The average particle size of the light diffusing material in the cured product obtained by curing the resin composition containing the light diffusing material is the equivalent circle diameter (major axis) of 50 particles by observing the particles using a scanning electron microscope. The geometric mean of the minor axis) can be calculated and calculated as the arithmetic mean value.

From the viewpoint of suppressing the aggregation of the light diffusing material in the resin composition, the light diffusing material preferably has an organic substance layer containing an organic substance on at least a part of the surface thereof. The organic substances contained in the organic substance layer include organic silane, organosiloxane, fluorosilane, organic phosphonate, organic phosphoric acid compound, organic phosphinate, organic sulfonic acid compound, carboxylic acid, carboxylic acid ester, carboxylic acid derivative, amide, and hydrocarbon. Examples thereof include waxes, polyolefins, copolymers of polyolefins, polyols, derivatives of polyols, alkanolamines, derivatives of alkanolamines, organic dispersants and the like.
The organic substance contained in the organic substance layer preferably contains a polyol, an organic silane, and the like, and more preferably contains at least one selected from the group consisting of the polyol and the organic silane.
Specific examples of organic silanes include octyltriethoxysilane, nonyltriethoxysilane, decyltriethoxysilane, dodecyltriethoxysilane, tridecyltriethoxysilane, tetradecyltriethoxysilane, pentadecyltriethoxysilane, and hexadecyltriethoxysilane. Examples thereof include silane, heptadecyltriethoxysilane, and octadecyltriethoxysilane.
Specific examples of the organosiloxane include polydimethylsiloxane (PDMS) terminated with a trimethylsilyl group, polymethylhydrosiloxane (PMHS), polysiloxane induced by functionalization of PMHS with an olefin (by hydrosilylation), and the like. ..
Specific examples of organic phosphonates include n-octylphosphonic acid and its ester, n-decylphosphonic acid and its ester, 2-ethylhexylphosphonic acid and its ester, and camphyl phosphonic acid and its ester.
Specific examples of the organic phosphoric acid compound include organic acidic phosphate, organic pyrophosphate, organic polyphosphate, organic metaphosphate, salts thereof and the like.
Specific examples of the organic phosphinate include n-hexylphosphinic acid and its ester, n-octylphosphinic acid and its ester, di-n-hexylphosphinic acid and its ester, and di-n-octylphosphinic acid and its ester. Can be mentioned.
Specific examples of the organic sulfonic acid compound include alkyl sulfonic acids such as hexyl sulfonic acid, octyl sulfonic acid, and 2-ethylhexyl sulfonic acid, these alkyl sulfonic acids, metal ions such as sodium, calcium, magnesium, aluminum, and titanium, and ammonium. Examples thereof include salts with ions and organic ammonium ions such as triethanolamine.
Specific examples of the carboxylic acid include maleic acid, malonic acid, fumaric acid, benzoic acid, phthalic acid, stearic acid, oleic acid, linoleic acid and the like.
Specific examples of the carboxylic acid ester include the above carboxylic acid, ethylene glycol, propylene glycol, trimethylolpropane, diethanolamine, triethanolamine, glycerol, hexanetriol, erythritol, mannitol, sorbitol, pentaerythritol, bisphenol A, hydroquinone, and flo. Examples thereof include esters and partial esters produced by the reaction with a hydroxy compound such as loglucinol.
Specific examples of the amide include stearic acid amide, oleic acid amide, and erucic acid amide.
Specific examples of the polyolefin and its copolymer include a copolymer of polyethylene, polypropylene, ethylene and one or more compounds selected from propylene, butylene, vinyl acetate, acrylate, acrylamide and the like. ..
Specific examples of the polyol include glycerol, trimethylolethane, trimethylolpropane and the like.
Specific examples of the alkanolamine include diethanolamine and triethanolamine.
Specific examples of the organic dispersant include high molecular weight organic dispersants having functional groups such as citric acid, polyacrylic acid, polymethacrylic acid, anionic, cationic, zwitterionic, and nonionic.
When the aggregation of the light diffusing material in the resin composition is suppressed, the dispersibility of the light diffusing material in the cured product tends to be improved.

The light diffusing material may have a metal oxide layer containing a metal oxide on at least a part of the surface thereof. Examples of the metal oxide contained in the metal oxide layer include silicon dioxide, aluminum oxide, zirconia, phosphoria, and boria. The metal oxide layer may be one layer or two or more layers. When the light diffusing material has two metal oxide layers, it preferably contains a first metal oxide layer containing silicon dioxide and a second metal oxide layer containing aluminum oxide.
When the light diffusing material has a metal oxide layer, the dispersibility of the light diffusing material in the cured product tends to be improved.

When the light diffusing material has an organic material layer containing an organic substance and a metal oxide layer, it is preferable that the metal oxide layer and the organic material layer are provided on the surface of the light diffusing material in the order of the metal oxide layer and the organic material layer.
When the light diffusing material has an organic material layer and two metal oxide layers, a first metal oxide layer containing silicon dioxide and a second metal oxide layer containing aluminum oxide are formed on the surface of the light diffusing material. It is preferable that the organic material layer is provided in the order of the first metal oxide layer, the second metal oxide layer, and the organic material layer (the organic material layer is the outermost layer).

When the resin composition contains a light diffusing material, the content of the light diffusing material in the wavelength conversion layer formed by curing the resin composition is, for example, 0.1% by mass with respect to the total amount of the wavelength conversion layer. It is preferably ~ 1.0% by mass, more preferably 0.2% by mass to 1.0% by mass, and even more preferably 0.3% by mass to 1.0% by mass.

(Liquid medium)
The resin composition may further contain a liquid medium. The liquid medium means a medium in a liquid state at 25 ° C.

Specific examples of the liquid medium include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, methyl-n-pentyl ketone, methyl-n-hexyl ketone, diethyl ketone, and the like. Ketone solvents such as dipropyl ketone, diisobutyl ketone, trimethylnonanone, cyclohexanone, cyclopentanone, methylcyclohexanone, 2,4-pentandione, acetonylacetone; diethyl ether, methyl ethyl ether, methyl-n-propyl ether, diisopropyl Ether, tetrahydrofuran, methyl tetrahydrofuran, dioxane, dimethyl dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, Diethylene glycol methyl-n-propyl ether, diethylene glycol methyl-n-butyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, diethylene glycol methyl-n-hexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, tri Ethylene glycol methyl ethyl ether, triethylene glycol methyl-n-butyl ether, triethylene glycol di-n-butyl ether, triethylene glycol methyl-n-hexyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol methyl ethyl Ether, tetraethylene glycol methyl-n-butyl ether, tetraethylene glycol di-n-butyl ether, tetraethylene glycol methyl-n-hexyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol Di-n-butyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol methyl-n-butyl ether, dipropi Lenglycol di-n-propyl ether, dipropylene glycol di-n-butyl ether, dipropylene glycol methyl-n-hexyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol methyl ethyl ether, tripropylene glycol methyl -N-butyl ether, tripropylene glycol di-n-butyl ether, tripropylene glycol methyl-n-hexyl ether, tetrapropylene glycol dimethyl ether, tetrapropylene glycol diethyl ether, tetrapropylene glycol methyl ethyl ether, tetrapropylene glycol methyl-n-butyl ether , Tetrapropylene glycol di-n-butyl ether, tetrapropylene glycol methyl-n-hexyl ether and other ether solvents; propylene carbonate, ethylene carbonate, diethyl carbonate and other carbonate solvents; methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate , N-butyl acetate, isobutyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 2- (2- (2-) Butoxyethoxy) ethyl, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetoacetate, diethylene glycol methyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, dipropylene glycol ethyl acetate ether , Glycol diacetate, methoxytriethylene glycol acetate, ethyl propionate, n-butyl propionate, isoamyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n lactate -Amil, ethylene glycol methyl ether propionate, ethylene glycol ethyl ether propionate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, γ -Ester solvents such as butyrolactone and γ-valerolactone; acetonitrile, N- Aprotonic polarities such as methylpyrrolidinone, N-ethylpyrrolidinone, N-propylpyrrolidinone, N-butylpyrrolidinone, N-hexylpyrrolidinone, N-cyclohexylpyrrolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, etc. Solvents: methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, n-pentanol, isopentanol, 2-methylbutanol, sec-pentanol, t-pentanol , 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, n-decanol , Se-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, cyclohexanol, methylcyclohexanol, benzyl alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, Alcohol solvents such as diethylene glycol, dipropylene glycol, triethylene glycol, and tripropylene glycol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether. , Diethylene glycol mono-n-hexyl ether, triethylene glycol monoethyl ether, tetraethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, etc. Glycol monoether solvent; terpene solvent such as terpinene, terpineol, milsen, aloosimene, limonene, dipentene, pinene, carboxylic, ossimen, ferlandrene; straight silicone oil such as dimethyl silicone oil, methylphenyl silicone oil, methylhydrogen silicone oil; Amino-modified silicone oil, epoxy-modified silicone oil, cal Boxy-modified silicone oil, carbinol-modified silicone oil, mercapto-modified silicone oil, heterologous functional group-modified silicone oil, polyether-modified silicone oil, methylstyryl-modified silicone oil, hydrophilic special-modified silicone oil, higher alkoxy-modified silicone oil, higher fatty acid Modified silicone oils such as modified silicone oils and fluorine-modified silicone oils; butanoic acid, pentanoic acid, hexanoic acid, heptanic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, Saturated aliphatic monocarboxylic acids having 4 or more carbon atoms such as hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanic acid, icosanoic acid, and eicosenoic acid; Saturated aliphatic monocarboxylic acids; and the like. When the resin composition contains a liquid medium, the resin composition may contain one kind of liquid medium alone or a combination of two or more kinds of liquid media.

When the resin composition contains a liquid medium, the content of the liquid medium in the resin composition is preferably, for example, 1% by mass to 10% by mass, and 4% by mass, based on the total amount of the resin composition. It is more preferably from 10% by mass to 10% by mass, and even more preferably from 4% by mass to 7% by mass.

(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 polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion imparting agent, an antioxidant, and a light stabilizer. Each component may be used alone or in combination of two or more.

(Method for preparing resin composition)
The resin composition can be prepared by mixing a phosphor, a polymerizable compound, a photopolymerization initiator, and if necessary, other components by a conventional method.

The wavelength conversion layer may be one obtained by curing one kind of resin composition, or may be one obtained by curing two or more kinds of resin compositions. For example, when the wavelength conversion member is in the form of a film, the wavelength conversion layer has different emission characteristics from the first cured product layer obtained by curing the resin composition containing the first phosphor and the first phosphor. A second cured product layer obtained by curing the resin composition containing the second phosphor may be laminated.

The average thickness of the wavelength conversion layer is not particularly limited, and is preferably, for example, 50 μm to 200 μm, more preferably 50 μm to 150 μm, and even more preferably 80 μm to 120 μm. When the average thickness of the wavelength conversion layer is 50 μm or more, the wavelength conversion efficiency tends to be further improved, and when the average thickness of the wavelength conversion layer is 200 μm or less, when the wavelength conversion member is applied to the backlight unit described later. In addition, there is a tendency that the backlight unit can be made thinner. The average thickness of the wavelength conversion layer is obtained as, for example, an arithmetic mean value of the thicknesses of any three points measured using a micrometer.

The wavelength conversion layer can be obtained, for example, by forming a coating film, a molded product, or the like of a resin composition, performing a drying treatment as necessary, and then irradiating with 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, it is irradiated with ultraviolet rays having a wavelength of 280 nm ~ 400 nm at an irradiation amount of ^{100mJ / cm 2 ~ 5000mJ / cm} 2. Examples of the ultraviolet source 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.

<Coating material>
The coating material is arranged on one main surface of the wavelength conversion layer or on both main surfaces. In the present disclosure, the "main surface" of the wavelength conversion layer represents two facing surfaces having the largest area of the wavelength conversion layer. The "side surface" of the wavelength conversion layer represents a surface other than the main surface of the wavelength conversion layer. The same applies to layers other than the wavelength conversion layer included in the wavelength conversion member. The "main surface" and the "side surface" may be flat or have a curved surface. The covering material is preferably placed on both main surfaces of the wavelength conversion layer.

The material of the covering material is not particularly limited, and polyester such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin such as polyethylene (PE) and polypropylene (PP); polyamide such as nylon; ethylene-vinyl alcohol co-weight. It may be coalescence (EVOH) or the like. From the viewpoint of availability, the material of the coating material is preferably at least one selected from the group consisting of polyethylene terephthalate and polypropylene.

The coating material preferably has a barrier property against at least one selected from the group consisting of oxygen and water, and more preferably has a barrier property against both oxygen and water, from the viewpoint of suppressing a decrease in the luminous efficiency of the phosphor. preferable. The coating material having a barrier property against at least one selected from the group consisting of oxygen and water is not particularly limited, and examples thereof include a barrier film having a base material layer and an inorganic layer. Examples of the base material layer include a base material layer formed from the above-mentioned materials. Examples of the inorganic substance forming the inorganic layer include silica and alumina. The method for producing the barrier film having the base material layer and the inorganic layer is not particularly limited, and examples thereof include a method of depositing an inorganic substance on one side or both sides of the base material layer.

When the coating material is a barrier film having a base material layer and an inorganic layer, the method of arranging the coating material and the wavelength conversion layer in the wavelength conversion member is not particularly limited, and the inorganic layer is arranged so as to face the wavelength conversion member. Is preferable. That is, it is preferable that the inorganic layer is arranged between the base material layer and the wavelength conversion layer. As a result, the barrier function tends to be suitably exhibited.

Oxygen permeability of the dressing, for example, is preferably ^{1.0mL / (m 2 · 24h ·} atm) or less, more preferably ^{0.8mL / (m 2 · 24h ·} atm) or less, 0 and more preferably ^{.6mL / (m 2 · 24h ·} atm) or less. The oxygen permeability of the coating material can be measured using an oxygen permeability measuring device (for example, MOCON, OX-TRAN) under the conditions of a temperature of 23 ° C. and a relative humidity of 90%.

Further, the water vapor permeability of the dressing, for example, more that that 1 × ¹⁰ is ^{0 g / (m 2 · 24h} ) or less ^{^{preferably, 8 × 10 -1 g / (}} m 2 · 24h) or less preferably, and more preferably ^{^{6 × 10 -1 g / (m}} 2 · 24h) or less. The water vapor permeability of the coating material can be measured using a water vapor permeability measuring device (for example, MOCON, AQUATRAN) under the conditions of a temperature of 40 ° C. and a relative humidity of 100%.

The covering material is preferably in the form of a sheet. The average thickness of the covering material is, for example, preferably 10 μm to 200 μm, more preferably 12 μm to 170 μm, and even more preferably 15 μm to 150 μm. When the average thickness is 10 μm or more, the functions such as barrier property tend to be sufficient, and when the average thickness is 200 μm or less, the decrease in light transmittance tends to be suppressed.
The average thickness of the covering material is obtained as, for example, an arithmetic mean value of the thicknesses of any three points measured using a micrometer.

<Protective layer>
The protective layer includes a metal oxide layer and a resin layer, and is arranged on the side surface of the wavelength conversion layer. Since the metal oxide is denser than the metal and is chemically stable, it is possible to satisfactorily exert the effect of suppressing the decrease in brightness at the end portion. Further, when the protective layer contains the resin layer, the decrease in brightness at the end portion of the wavelength conversion member tends to be suppressed more satisfactorily. The reason for this is not always clear, but the introduction of the resin layer alleviates the difference in the coefficient of thermal expansion between the protective layer and the wavelength conversion layer, and the expansion or contraction of the wavelength conversion member with temperature changes causes the barrier property of the metal oxide layer. It is presumed that this is because the decrease in is suppressed.

Examples of the metal oxide contained in the metal oxide layer include silica, alumina, niobium oxide, cerium oxide, and titanium oxide. One type of metal oxide may be used alone, or two or more types may be used in combination. Of these, it is preferable to use silica and alumina together.

Examples of the resin forming the resin layer include acrylic resin, urethane resin, thiol resin, fluorine resin and the like, and among them, acrylic resin is preferable. Examples of the acrylic resin include poly (meth) acrylic acid ester and a copolymer of (meth) acrylic acid ester and other components. Examples of the acrylic resin include polymethylmethacrylate (PMMA). As the resin forming the resin layer, one type may be used alone or two or more types may be used in combination.

The protective layer may be, for example, a protective layer formed by forming a metal oxide layer on a base material which is a resin layer. The method for forming the metal oxide is not particularly limited, and examples thereof include an atomic layer deposition method, sputtering, a chemical vapor deposition method (CVD), a physical vapor deposition method (PVD), and a molecular beam epitaxy method (MBE). Among them, according to the atomic layer deposition method, it is possible to suppress the occurrence of pinholes and form a dense metal oxide layer, which is preferable from the viewpoint of barrier properties. Further, when the phosphor contained in the wavelength conversion layer is a phosphor having a property of being easily deteriorated by high temperature (quantum dot phosphor or the like), the room temperature atomic layer deposition method is useful. According to the room temperature atomic layer deposition method, it is possible to better suppress the decrease in brightness at the end without deteriorating the phosphor due to heat.

The protective layer may include a layer other than the metal oxide layer and the resin layer. From the viewpoint of better suppressing the decrease in brightness at the end of the wavelength conversion member, the protective layer includes a metal oxide layer and a resin layer, and the metal oxide layer and the resin layer are adjacent to each other. Is preferable. Further, from the viewpoint of simplification of production, the protective layer may be composed of a metal oxide layer and a resin layer (that is, includes only the metal oxide and the resin layer) and may not include other layers.

The protective layer may be arranged on at least a part of the side surface of the wavelength conversion layer, may be arranged on the entire side surface of the wavelength conversion layer, or may be further arranged on the side surface of the wavelength conversion layer. For example, the protective layer may be arranged on a part or the whole of the side surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer. Further, the protective layer may cover the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer. In the present disclosure, the outer peripheral surface of the layered member represents a surface including the main surface and the side surface of the layered member.

In one embodiment, the metal oxide layer contained in the protective layer covers the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer. The outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer coated on the resin layer may be coated.

In one aspect, the metal oxide layer may be arranged outside the resin layer on the side surface of the wavelength conversion layer. Therefore, on the side surface of the wavelength conversion layer, the resin layer and the metal oxide layer may be arranged in this order from the wavelength conversion layer side. On the contrary, on the side surface of the wavelength conversion layer, the resin layer may be arranged outside the metal oxide layer. Therefore, on the side surface of the wavelength conversion layer, the metal oxide layer and the resin layer may be arranged in this order from the wavelength conversion layer side. In a further aspect, the metal oxide layer may form the outermost layer or the resin layer may form the outermost surface on the side surface of the wavelength conversion layer.

The average thickness of the protective layer is not particularly limited. For example, the average thickness of the protective layer is preferably 5 nm to 500 nm, more preferably 10 nm to 300 nm, further preferably 20 nm to 100 nm, and particularly preferably 30 nm to 90 nm. When the average thickness of the protective layer is 5 nm or more, the decrease in brightness tends to be suppressed more satisfactorily. When the average thickness of the protective layer is 500 nm or less, the manufacturing cost tends to be suppressed.

The thickness of the metal oxide layer in the protective layer (when the metal oxide layer contains a plurality of metal oxides, the total thickness of the metal oxide layers formed by the plurality of metal oxides) is 0. It is preferably 1 nm to 100 nm, more preferably 0.5 nm to 50 nm, and even more preferably 1 nm to 40 nm. When the thickness of the metal oxide layer is 0.1 nm or more, sufficient barrier properties tend to be obtained, and when the thickness of the metal oxide layer is 100 nm or less, the production cost tends to be suppressed.

In one embodiment, when the protective layer contains a silica layer and an alumina layer, the silica layer is preferably 0.1 nm to 40 nm, more preferably 0.2 nm to 30 nm, and further preferably 0.3 nm to 20 nm. An alumina layer of preferably 0.1 nm to 40 nm, more preferably 0.2 nm to 30 nm, still more preferably 0.3 nm to 20 nm may be contained. By adopting such a configuration, it tends to be possible to suppress the deliquescent that may occur in a high humidity and high temperature environment when alumina alone is used, and to improve the reliability.

The thickness of the resin layer is preferably 4.9 nm to 499.9 nm, more preferably 9.5 nm to 299.5 nm, further preferably 19 nm to 199.5 nm, and 30 nm to 100 nm. Is particularly preferred.

The average thickness of the protective layer and the average thickness of each layer in the protective layer are obtained as the arithmetic mean value of the thicknesses of any three points measured by energy dispersive X-ray analysis.

Hereinafter, a specific example of the wavelength conversion member having the protective layer will be described with reference to the drawings, but the wavelength conversion member according to the present embodiment is not limited to the mode shown in the drawings.

In FIG. 1, a protective layer 15 including a metal oxide layer 13 and a resin layer 14 is arranged on a side surface of a laminate in which

coating materials

12A and 12B are arranged on both main surfaces of the wavelength conversion layer 11. An example of the wavelength conversion member 10 is shown. In FIG. 1, the metal oxide layer 13 is arranged inside and the resin layer 14 is arranged outside, but the resin layer 14 is arranged inside and the metal oxide layer 13 is arranged outside. You may.
When the former configuration in which the metal oxide layer 13 is arranged inside and the resin layer 14 is arranged outside is adopted, there is a tendency that the decrease in brightness at the end portion of the wavelength conversion member 10 can be suppressed more satisfactorily. The reason for this is not clear, but it is presumed that the metal oxide layer 13 is suitably protected by the resin layer and the physical or chemical deterioration of the metal oxide is suitably suppressed.
When the latter configuration in which the resin layer 14 is arranged inside and the metal oxide layer 13 is arranged outside is adopted, the moisture and heat resistance tends to be further improved. Although the reason for this is not clear, since the resin layer 14 is arranged inside, the strain in a high temperature environment due to the difference in the coefficient of linear expansion between the metal oxide layer 13 and the wavelength conversion member 10 can be relaxed. It is presumed that this is because the deterioration of the metal oxide layer 13 is suppressed.

In FIG. 2, the outer peripheral surface of the laminate in which the

coating materials

12A and 12B are arranged on both main surfaces of the wavelength conversion layer 11 is covered with the protective layer 15 including the metal oxide layer 13 and the resin layer 14. An example of a wavelength conversion member is shown. In FIG. 2, the metal oxide layer 13 is arranged inside and the resin layer 14 is arranged outside, but the resin layer 14 is arranged inside and the metal oxide layer 13 is arranged outside. You may.
When the former configuration in which the metal oxide layer 13 is arranged inside and the resin layer 14 is arranged outside is adopted, there is a tendency that the decrease in brightness at the end portion can be suppressed more satisfactorily. The reason for this is not clear, but it is presumed that the metal oxide layer 13 is suitably protected by the resin layer and the physical or chemical deterioration of the metal oxide is suitably suppressed.
When the latter configuration in which the resin layer 14 is arranged inside and the metal oxide layer 13 is arranged outside is adopted, the moisture and heat resistance tends to be further improved. Although the reason for this is not clear, since the resin layer 14 is arranged inside, the strain in a high temperature environment due to the difference in the coefficient of linear expansion between the metal oxide layer 13 and the wavelength conversion member 10 can be relaxed. It is presumed that this is because the deterioration of the metal oxide layer 13 is suppressed.
When the metal oxide layer is formed by the atomic layer deposition method, as shown in FIG. 2, it is possible to relatively easily form a structure in which the outer peripheral surface of the laminate is covered with the metal oxide layer 13. ..

In the wavelength conversion members shown in FIGS. 1 and 2, the types and average thicknesses of the coating material 12A and the coating material 12B may be the same or different, respectively.

≪Manufacturing method of wavelength conversion member≫
In the method for manufacturing a wavelength conversion member according to an embodiment of the present disclosure, a wavelength conversion layer containing a phosphor and a coating material arranged on one main surface or both main surfaces of the wavelength conversion layer are provided. A step of forming a protective layer including a metal oxide layer and a resin layer on the side surface of the laminated body is included. The above-mentioned contents can be applied to the details of the wavelength conversion member.

The step of forming the protective layer may include a step of forming the metal oxide layer and a step of forming the resin layer in any order. The step of forming the protective layer may include a step of forming the metal oxide layer and a step of forming the resin layer in this order.

In one aspect, is the metal oxide layer formed so as to cover the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer? Or, it may be formed so as to cover the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer coated on the resin layer. .. In a further aspect, the protective layer may be formed to cover the outer peripheral surface of the laminate.

The wavelength conversion member of this embodiment can be manufactured by, for example, the following manufacturing method. First, a resin composition for forming a wavelength conversion layer is applied to the surface of a film-like coating material (hereinafter, also referred to as “first coating material”) that is continuously conveyed to form a coating film. The method of applying the resin composition is not particularly limited, and examples thereof include a die coating method, a curtain coating method, an extrusion coating method, a rod coating method, and a roll coating method.

Next, a film-like coating material (hereinafter, also referred to as "second coating material") that is continuously conveyed is attached onto the coating film of the resin composition.

Next, the coating film is cured and a cured product layer is formed by irradiating the active energy rays from the side of the first coating material and the second coating material that can transmit the active energy rays. If neither the first coating material nor the second coating material can transmit the active energy rays, the coating film is irradiated with the active energy rays before the second coating material is bonded, and the cured product layer is formed. May be formed. Then, by cutting out to a desired size, a laminate of the first coating material, the cured product layer, and the second coating material can be produced.

Subsequently, a protective layer including a metal oxide layer and a resin layer is formed on the side surface of the laminate produced as described above. The method of forming the protective layer is not particularly limited. For example, a metal oxide layer is formed on the side surface or the outer peripheral surface of the laminate, and then a resin composition for forming a resin layer is applied to the outer peripheral surface of the metal oxide layer, and the resin composition is dried or cured as necessary. The resin layer may be formed by this. Further, the resin layer may be formed on the side surface or the outer peripheral surface of the laminate first, and then the metal oxide layer may be coated on the outer peripheral surface of the resin layer. Examples of the method for forming the metal oxide layer include an atomic layer deposition method, sputtering, a chemical vapor deposition method (CVD), a physical vapor deposition method (PVD), and a molecular beam epitaxy method (MBE). Examples of the method for applying the resin composition for forming the resin layer include the methods exemplified as the above-mentioned method for applying the resin composition for forming the wavelength conversion layer.

≪Backlight unit≫
The backlight unit according to the embodiment of the present disclosure includes the above-mentioned wavelength conversion member and a light source.

The backlight unit is preferably a multi-wavelength light source from the viewpoint of improving color reproducibility. In a preferred embodiment, blue light having an emission center wavelength in the wavelength range of 430 nm to 480 nm and having an emission intensity peak having a half-value width of 100 nm or less, and emission center wavelength in the wavelength range of 520 nm to 560 nm. A back that emits green light having an emission intensity peak having a half-value width of 100 nm or less and red light having an emission center wavelength in the wavelength range of 600 nm to 680 nm and having an emission intensity peak having a half-value width of 100 nm or less. The light unit can be mentioned. The half-value width of the emission intensity peak means the peak width at a height of 1/2 of the peak height.

From the viewpoint of further improving the 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. 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.

Further, from the viewpoint of further improving the color reproducibility, the half-value width of each emission intensity peak of the blue light, green light, and red light emitted by the backlight unit is preferably 80 nm or less, preferably 50 nm or less. 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 a emission center wavelength in the wavelength range of 430 nm to 480 nm can be used. Examples of the light source include an LED (Light Emitting Diode) and a laser. When a light source that emits blue light is used, the wavelength conversion member preferably includes at least a quantum dot phosphor R that emits red light and a quantum dot phosphor G that emits green light. As a result, white light can be obtained from the red light and green light emitted from the wavelength conversion member and the blue light transmitted through the wavelength conversion member.

Further, as the light source of the backlight unit, for example, a light source that emits ultraviolet light having a emission center wavelength in the wavelength range of 300 nm to 430 nm can be used. Examples of the light source include LEDs and lasers. When a light source that emits ultraviolet light is used, the wavelength conversion member preferably includes a quantum dot phosphor B that is excited by excitation light and emits blue light, together with a quantum dot phosphor R and a quantum dot phosphor G. As a result, white light can be obtained from the red light, green light, and blue light emitted from the wavelength conversion member.

The backlight unit of the present embodiment may be an edge light type or a direct type.

FIG. 3 shows an example of a schematic configuration of an edge light type backlight unit.

The backlight unit 20 shown in FIG. 3 includes a light source 21 for emitting the blue light L _B, a light guide plate 22 to be emitted guiding the blue light L _B emitted from the light source 21, the light guide plate 22 and disposed to face The wavelength conversion member 10, the retroreflective member 23 which is arranged to face the light source plate 22 via the wavelength conversion member 10, and the reflector 24 which is arranged to face the wavelength conversion member 10 via the light guide plate 22. Be prepared. Wavelength conversion member 10 emits the red light L _R and the green light L _G part of the blue light L _B as the excitation light, the red light L and _R and the green light L _G, the blue light was not the excitation light L _B and are emitted. The red light _{L R,} the green light _{L G,} and the blue light _{L B,} the white light _{L W} is emitted from the retroreflective member 23.

≪Image display device≫
The image display device according to the embodiment of the present disclosure includes the backlight unit described above. The image display device is not particularly limited, and examples thereof include a liquid crystal display device such as a television, a personal computer, and a mobile phone.

FIG. 4 shows an example of the schematic configuration of the liquid crystal display device.

The liquid crystal display device 30 shown in FIG. 4 includes a backlight unit 20 and a liquid crystal cell unit 31 arranged to face the backlight unit 20. The liquid crystal cell unit 31 has a configuration in which the liquid crystal cell 32 is arranged between the polarizing plate 33A and the polarizing plate 33B.

The drive method of the liquid crystal cell 32 is not particularly limited, and is a TN (Twisted Nematic) method, an STN (Super Twisted Nematic) method, a VA (Vertical Birefringence) method, an IPS (In-Plane-Switching) method, and an OCB (Optical Birefringence) method. The method and the like can be mentioned.

Next, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples.

<Example 1>
[Manufacturing of wavelength conversion member]
The materials shown below were mixed to prepare a resin composition.
・ Tricyclodecanedimethanol diacrylate (manufactured by Sartmer)
-Pentaerythritol tetrakis (3-mercaptopropionate) (manufactured by Evans Chemetics)
-Titanium oxide powder (trade name: R-706, manufactured by The Chemours Company)
-4-Hydroxy-2,2,6,6-tetramethylpiperidin-N-oxyl (trade name: LA-7RD, manufactured by ADEKA CORPORATION)
・ 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (trade name: TPO, manufactured by BASF Japan Ltd.)
-Quantum dot dispersion (green, manufactured by Nanosys, Inc.) and quantum dot dispersion (red, manufactured by Nanosys, Inc.)

The obtained resin composition was applied as a coating material to the anti-matte surface of a barrier film having a thickness of 72 μm to form a coating film. The same coating material as above was placed on this coating film. Next, ultraviolet rays were irradiated using an ultraviolet irradiation device (Igraphics Co., Ltd.) (irradiation amount: 1000 mJ / cm ² ) to cure the resin composition, and coating materials were arranged on both sides of the wavelength conversion layer. The wavelength conversion member of was manufactured.

Each wavelength conversion member obtained above was cut into a circular dimension having a diameter of 20 mm to prepare a measurement sample.

[Formation of resin layer (buffer layer)]
The obtained circular measurement sample having a diameter of 20 mm was placed on the rotating part of the spin coating device and fixed by operating the vacuum pump. 1 mL of the polymer solution was added dropwise while rotating the measurement sample at a rate of 800 rpm. The polymer solution was prepared by the following method. Polymethylmethacrylate (PMMA, Tokyo Chemical Industry Co., Ltd.) in a solvent prepared by mixing acetone (manufactured by Tokyo Chemical Industry Co., Ltd.) and p-xylene (manufactured by Tokyo Chemical Industry Co., Ltd.) so as to have a mass ratio of 5: 1. (Manufactured by the company) was dissolved and stirred until the solid matter completely disappeared to prepare a polymer solution.
After dropping the polymer solution, the spin coating was continuously rotated for 60 seconds, and then the measurement sample was allowed to stand for 30 minutes to completely evaporate and remove the solvent. All of the above was done in a nitrogen-conditioned glove box.

[Lamination of metal oxide layer]
A polymer-coated measurement sample was placed in a vacuum chamber and evacuated with an oil rotary pump and a turbo molecular pump until the ^{degree of vacuum reached 2 × 10 -3 Pa.} At this time, the chamber was not heated in particular, and all were carried out in a room temperature environment. After introducing trimethylaluminum (TMA) into the vacuum chamber, the inside of the system was once exhausted. By this operation, a molecular layer of TMA was deposited on the entire surface and edges of the measurement sample. Subsequently, a mixed gas of water vapor and argon was introduced to oxidize the molecular layer of TMA to form an aluminum layer. By repeating these operations, an atomic layer of aluminum was deposited on the measurement sample and repeated until a predetermined thickness was reached.

<Comparative example 1>
[Manufacturing of wavelength conversion member]
The materials shown below were mixed to prepare a resin composition.
・ Tricyclodecanedimethanol diacrylate (manufactured by Sartmer)
-Pentaerythritol tetrakis (3-mercaptopropionate) (manufactured by Evans Chemetics)
-Titanium oxide powder (trade name: R-706, manufactured by The Chemours Company)
-4-Hydroxy-2,2,6,6-tetramethylpiperidin-N-oxyl (trade name: LA-7RD, manufactured by ADEKA CORPORATION)
・ 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (trade name: TPO, manufactured by BASF Japan Ltd.)
-Quantum dot dispersion (green, manufactured by Nanosys, Inc.) and quantum dot dispersion (red, manufactured by Nanosys, Inc.)

Each wavelength conversion member obtained above was cut into a circle with a diameter of 20 mm to prepare a measurement sample.

[Lamination of metal oxide layer]
The measurement sample was placed in a vacuum chamber and evacuated with an oil rotary pump and a turbo molecular pump until the ^{degree of vacuum reached 2 × 10 -3 Pa.} At this time, the chamber was not heated in particular, and all were carried out in a room temperature environment. After introducing trimethylaluminum (TMA) into the vacuum chamber, the inside of the system was once exhausted. By this operation, a molecular layer of TMA was deposited on the entire surface and edges of the measurement sample. Subsequently, a mixed gas of water vapor and argon was introduced to oxidize the molecular layer of TMA to form an aluminum layer. By repeating these operations, an atomic layer of aluminum was deposited on the measurement sample and repeated until a predetermined thickness was reached.

<Comparative example 2>
[Manufacturing of wavelength conversion member]
The materials shown below were mixed to prepare a resin composition.
・ Tricyclodecanedimethanol diacrylate (manufactured by Sartmer)
-Pentaerythritol tetrakis (3-mercaptopropionate) (manufactured by Evans Chemetics)
-Titanium oxide powder (trade name: R-706, manufactured by The Chemours Company)
-4-Hydroxy-2,2,6,6-tetramethylpiperidin-N-oxyl (trade name: LA-7RD, manufactured by ADEKA CORPORATION)
・ 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (trade name: TPO, manufactured by BASF Japan Ltd.)
-Quantum dot dispersion (green, manufactured by Nanosys, Inc.) and quantum dot dispersion (red, manufactured by Nanosys, Inc.)

<Evaluation of edge deterioration and brightness reduction in moisture resistance test>
A constant temperature bath in which the temperature and humidity can be set was set to a temperature of 65 ° C. and a relative humidity of 95%, and the above measurement sample was installed. After 200 hours, the measurement sample was taken out and irradiated with black light to observe the state of the edge of the measurement sample. Using image analysis software or the like, the distance of the portion where the brightness of the edge of the measurement sample was 85% or less of the brightness of the center was measured, and this was defined as the edge deterioration distance (mm). In addition, the brightness of the entire measurement sample after 200 hours was measured to calculate the value of the ratio to the initial ratio (the maintenance rate to the initial brightness). The results are shown in Table 1.

According to this study, the presence of the metal oxide ALD layer and buffer layer suppressed the progress of edge deterioration and achieved a high brightness maintenance rate.

The disclosure of Japanese Patent Application No. 2019-217537 is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards described herein are to the same extent as if the individual documents, patent applications, and technical standards were specifically and individually stated to be incorporated by reference. Incorporated herein by reference.

10 ... Wavelength conversion member 11 ...

Wavelength conversion layer

12A, 12B ... Coating material 13 ... Metal oxide layer 14 ... Resin layer 15 ... Protective layer 20 ... Backlight unit 21 ... Light source 22 ... Light guide plate 23 ... Retroreflective member 24 ... reflector 30 ... liquid crystal display device 31 ... liquid crystal cell unit 32 ... liquid crystal cell 33A ... polarizing plate 33B ... polarizing plate _{L B} ... blue light _{L R} ... red light _{L G} ... green light _{L W} ... white light

Claims

A wavelength conversion layer containing a phosphor and
A coating material arranged on one main surface or both main surfaces of the wavelength conversion layer,
A protective layer including a metal oxide layer and a resin layer arranged on the side surface of the wavelength conversion layer, and
Wavelength conversion member having.
The wavelength conversion member according to claim 1, wherein the resin layer is arranged outside the metal oxide layer on the side surface of the wavelength conversion layer.
The wavelength conversion member according to claim 1 or 2, wherein the resin layer forms the outermost surface on the side surface of the wavelength conversion layer.
The wavelength conversion member according to any one of claims 1 to 3, wherein the resin layer contains a poly (meth) acrylic acid ester.
Any of claims 1 to 4, wherein the protective layer covers the outer peripheral surface of the laminate in which the coating material is arranged on one main surface or both main surfaces of the wavelength conversion layer. The wavelength conversion member according to item 1.
A backlight unit including the wavelength conversion member according to any one of claims 1 to 5 and a light source.
An image display device including the backlight unit according to claim 6.
A metal oxide layer and a resin layer are included on the side surface of the laminate having a wavelength conversion layer containing a phosphor and a coating material arranged on one main surface or both main surfaces of the wavelength conversion layer. A method for manufacturing a wavelength conversion member, which comprises a step of forming a protective layer.
The method for manufacturing a wavelength conversion member according to claim 8, wherein the metal oxide layer is formed by an atomic layer deposition method.
The production of the wavelength conversion member according to claim 8 or 9, wherein the step of forming the protective layer includes a step of forming the metal oxide layer and a step of forming the resin layer in this order. Method.
The method for manufacturing a wavelength conversion member according to any one of claims 8 to 10, wherein the resin layer contains a poly (meth) acrylic acid ester.
The method for manufacturing a wavelength conversion member according to any one of claims 8 to 11, wherein the protective layer is formed so as to cover the outer peripheral surface of the laminated body.