JP2019174565A - Wavelength conversion member, backlight unit, image display device, resin composition for wavelength conversion member, and cured resin product - Google Patents

Abstract

Provided are a wavelength conversion member, a backlight unit, an image display device, a resin composition for a wavelength conversion member, and a cured resin, which are excellent in adhesiveness of a cured resin without impairing heat and moisture resistance.
A wavelength conversion member comprising a cured resin containing a structural unit derived from a (meth) allyl compound, a structural unit derived from a monofunctional thiol compound, and a quantum dot phosphor.
[Selection figure] None

Description

  The present disclosure relates to a wavelength conversion member, a backlight unit, an image display device, a resin composition for a wavelength conversion member, and a cured resin.

  In recent years, in the field of image display devices such as liquid crystal display devices, it has been required to improve color reproducibility of displays, and wavelength conversion members including quantum dot phosphors have attracted attention as means for improving color reproducibility. (See, for example, Patent Document 1 and Patent Document 2).

  The wavelength conversion member containing quantum dot fluorescent substance is arrange | positioned at the backlight unit of an image display apparatus, 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 emits light. White light can be obtained by the red light and the green light and the blue light transmitted through the wavelength conversion member. With the development of wavelength conversion members including quantum dot phosphors, the color reproducibility of displays has been expanded from 72% of the conventional NTSC (National Television System Committee) ratio to 100% of the NTSC ratio.

  The wavelength conversion member including the quantum dot phosphor is usually formed by curing a curable composition containing the quantum dot phosphor.

Special table 2013-544018 gazette International Publication No. 2016/052625

In the wavelength conversion member containing quantum dot fluorescent substance, at least one part of the hardened | cured material containing quantum dot fluorescent substance may be coat | covered with a coating | covering material.
If the adhesive between the cured product containing the quantum dot phosphor and the coating material is not sufficient, for example, when the wavelength conversion member is cut to a specified size, the coating material is peeled off, and the cut wavelength conversion member is heated to a high temperature. When left under humidity, the quantum dot phosphor may deteriorate and the emission intensity may decrease.

  In view of the above circumstances, the present invention provides a wavelength conversion member, a backlight unit, an image display device, a resin composition for a wavelength conversion member, and a resin cured product that are excellent in adhesiveness of a cured resin without impairing heat and moisture resistance. This is the issue.

Specific means for solving the above problems include the following embodiments.
<1> A wavelength conversion member including a resin cured product including a structural unit derived from a (meth) allyl compound, a structural unit derived from a monofunctional thiol compound, and a quantum dot phosphor.
<2> The wavelength conversion member according to <1>, wherein the cured resin further includes a structural unit derived from a polyfunctional thiol.
<3> The wavelength conversion member according to <1> or <2>, wherein the cured resin has a sulfide bond.
<4> The wavelength conversion member according to any one of <1> to <3>, wherein the monofunctional thiol compound has a molecular weight of 100 g / mol to 350 g / mol.
<5> The monofunctional thiol compound includes 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, 3- Selected from the group consisting of 3-methoxybutyl mercaptopropionate, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, and n-octyl-3-mercaptopropionate The wavelength conversion member according to any one of <1> to <4>, which is at least one kind.
<6> The wavelength conversion member according to any one of <1> to <5>, wherein the cured resin has a glass transition temperature (Tg) of 20 ° C to 45 ° C.
<7> The storage elastic modulus (E ′) of the cured resin measured by dynamic viscoelasticity measurement at a frequency of 10 Hz and a temperature of 25 ° C. is 1 × 10 ⁷ Pa to 1 × 10 ⁹ Pa <1> to The wavelength conversion member as described in any one of <6>.
<8> The wavelength conversion member according to any one of <1> to <7>, wherein the cured resin is in a film form.
<9> The wavelength conversion member according to any one of <1> to <8>, further including a covering material that covers at least a part of the cured resin.
<10> The wavelength conversion member according to <9>, wherein the coating material has a barrier property against at least one of oxygen and water.
<11> The wavelength conversion member according to <9> or <10>, wherein a peel strength of the cured resin with respect to the coating material is 4 N / 25 mm or more.
<12> The wavelength conversion member according to any one of <1> to <11>, wherein the quantum dot phosphor includes a compound including at least one selected from the group consisting of Cd and In.
<13> A backlight unit comprising the wavelength conversion member according to any one of <1> to <12> and a light source.
<14> An image display device comprising the backlight unit according to <13>.

<15> A resin composition for a wavelength conversion member, comprising a (meth) allyl compound, a monofunctional thiol compound, a photopolymerization initiator, and a quantum dot phosphor.
<16> The resin composition for a wavelength conversion member according to <15>, wherein the monofunctional thiol compound has a molecular weight of 100 g / mol to 350 g / mol.
<17> The monofunctional thiol compound includes 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, 3- Selected from the group consisting of 3-methoxybutyl mercaptopropionate, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, and n-octyl-3-mercaptopropionate The resin composition for wavelength conversion members according to <15> or <16>, which is at least one kind.
<18> The resin composition for a wavelength conversion member according to any one of <15> to <17>, further including a polyfunctional thiol compound.
<19> The resin composition for a wavelength conversion member according to any one of <15> to <18>, wherein the quantum dot phosphor includes a compound containing at least one selected from the group consisting of Cd and In. .
<20> A cured resin, which is a cured product of the resin composition for a wavelength conversion member according to any one of <15> to <19>.

  According to the present disclosure, there are provided a wavelength conversion member, a backlight unit, an image display device, a resin composition for a wavelength conversion member, and a resin cured product that are excellent in adhesiveness of a cured resin without impairing heat and moisture resistance.

It is a schematic cross section which shows an example of schematic structure of the wavelength conversion member of this indication. It is a figure which shows an example of schematic structure of the backlight unit of this indication. It is a figure which shows an example of schematic structure of the liquid crystal display device of this indication.

  Hereinafter, embodiments of the present invention will be described. 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 numerical values and ranges thereof, and the present invention is not limited thereto.

In the present disclosure, the numerical ranges indicated using “to” include numerical values described before and after “to” as the minimum value and the maximum value, respectively.
In the numerical ranges 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 description. . Further, in the numerical ranges described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the values shown in the examples.
In the present disclosure, each component may contain a plurality of corresponding substances. When multiple types 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 multiple types of substances present in the composition unless otherwise specified. Means quantity.
In the present disclosure, a plurality of particles corresponding to each component may be included. When a plurality of particles corresponding to each component are present in the composition, the particle diameter 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 “film” includes only a part of the region in addition to the case where the layer or film is formed over the entire region. The case where it is formed is also included.
In the present disclosure, the term “lamination” indicates that layers are stacked, and two or more layers may be combined, or two or more layers may be detachable.
In the present disclosure, “(meth) allyl” means allyl or methallyl, “(meth) acryl” means acryl or methacryl, “(meth) acryloyl” means acryloyl or methacryloyl, “( “Meth) acrylate” means acrylate or methacrylate.
In the present disclosure, a (meth) allyl compound means a compound having a (meth) allyl group in a molecule, and a (meth) acrylic compound means a compound having a (meth) acryloyl group in a molecule. A compound having both a (meth) allyl group and a (meth) acryloyl group in the molecule is classified as a (meth) allyl compound for convenience.

<Wavelength conversion member>
The wavelength conversion member of the present disclosure includes a cured resin including a structural unit derived from a (meth) allyl compound, a structural unit derived from a monofunctional thiol compound, and a quantum dot phosphor.
The wavelength conversion member of this indication may further have other members, such as a covering material, as needed.

The reason why the wavelength conversion member of the present disclosure is excellent in the adhesiveness of the cured resin without impairing the heat and moisture resistance is presumed as follows.
The cured resin contained in the wavelength conversion member can be formed, for example, by curing a resin composition containing a compound having a polymerizable group and a quantum dot phosphor. When this resin composition contains a monofunctional thiol compound, an addition reaction between the monofunctional thiol compound and the compound having a polymerizable group proceeds. Since the monofunctional thiol compound has one thiol group, no further addition reaction from the monofunctional thiol compound occurs, and a low molecular weight reactant is generated as compared with the case where no monofunctional thiol compound is contained. The resin cured product obtained by this tends to improve the tackiness, and when a coating material or the like is provided on the resin cured product, it is considered that the resin cured product has excellent adhesion to the coating material or the like.
Furthermore, the quantum dot phosphor tends to be protected by the reactant obtained by the addition reaction. Therefore, it is thought that the wavelength conversion member containing this quantum dot fluorescent substance is hard to impair wet heat resistance.
For the reasons described above, the wavelength conversion member of the present disclosure is presumed to be excellent in the adhesiveness of the cured resin without impairing the heat and moisture resistance.

(Cured resin)
The cured resin according to the present disclosure includes a structural unit derived from a (meth) allyl compound, a structural unit derived from a monofunctional thiol compound, and a quantum dot phosphor.
The cured resin may further include other components other than those described above. Examples of other components include a structural unit derived from a compound having a polymerizable group other than a structural unit derived from a (meth) allyl compound and a structural unit derived from a monofunctional thiol compound. The resin cured product may further contain a dispersoid, a liquid medium, a polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion promoter, an antioxidant, and the like.
The cured resin may be a cured product of a resin composition for wavelength conversion member described later.

When the resin cured product according to the present disclosure includes a dispersoid, the dispersoid may include a quantum dot phosphor from the viewpoint of excellent emission intensity, and the quantum dot phosphor is dispersed in the dispersoid. It is preferable.
In addition, when the resin cured product according to the present disclosure includes a dispersoid, it is not limited to a configuration in which all the quantum dot phosphors exist in the dispersoid, and at least one quantum dot phosphor exists outside the dispersoid. Alternatively, a part of at least one quantum dot phosphor may exist outside the dispersoid.

  The resin cured product according to the present disclosure includes a quantum dot phosphor. The quantum dot phosphor is not particularly limited, and examples thereof include particles containing at least one selected from the group consisting of II-VI group compounds, III-V group compounds, IV-VI group compounds, and IV group compounds. From the viewpoint of luminous efficiency, the quantum dot phosphor preferably contains a compound containing at least one of Cd and In.

Specific examples of the II-VI group compounds include CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeS, HgSeS, HgSeS, HgSeS CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, GdHgSe, ST
Specific examples of the III-V group compounds include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb. , AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNS, InAlNb, InAlNs, InAlNb, InAlNs, InAlNb, InAlNs, InAlNb, InAlNS
Specific examples of the IV-VI group compounds include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, Sn, SnPbTe, Sn, SnPbTe, Sn, etc. .
Specific examples of the group IV compound include Si, Ge, SiC, SiGe and the like.

  As a quantum dot fluorescent substance, what has a core-shell structure is preferable. By making the band gap of the compound constituting the shell layer wider than the band gap of the compound constituting the core part, it becomes possible to further improve the quantum efficiency of the quantum dot phosphor. Examples of the combination of the core part and the shell layer (core part / shell layer) include CdSe / ZnS, InP / ZnS, PbSe / PbS, CdSe / CdS, CdTe / CdS, and CdTe / ZnS.

  The quantum dot phosphor may have a so-called core multishell structure in which the shell layer has a multilayer structure. By stacking one or more shell layers with a narrow band gap on the core portion with a wide band gap, and further stacking a shell layer with a wide band gap on the shell layer, the quantum efficiency of the quantum dot phosphor can be improved. Further improvement is possible.

  The cured resin according to the present disclosure may contain one kind of quantum dot phosphor alone or may contain two or more kinds of quantum dot phosphors. As an aspect including two or more types of quantum dot phosphors, for example, an aspect including two or more types of quantum dot phosphors having the same average particle diameter but having different components, and quantum dot fluorescence having the same components having different average particle diameters Examples include an aspect including two or more types of bodies and an aspect including two or more types of quantum dot phosphors having different components and average particle diameters. By changing at least one of the components of the quantum dot phosphor and the average particle diameter, the emission center wavelength of the quantum dot phosphor can be changed.

  For example, the resin cured product according to the present disclosure includes a quantum dot phosphor G having an emission center wavelength in a green wavelength region of 520 nm to 560 nm and a quantum dot phosphor having an emission center wavelength in a red wavelength region of 600 nm to 680 nm. R may be included. When the cured resin containing the quantum dot phosphor G and the quantum dot phosphor R is irradiated with excitation light in a blue wavelength region of 430 nm to 480 nm, green light is emitted from the quantum dot phosphor G and the quantum dot phosphor R, respectively. And red light is 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 resin.

  The content of the quantum dot phosphor in the cured resin is preferably, for example, 0.01% by mass to 1.0% by mass with respect to the total mass of the cured resin, and 0.05% by mass to 0%. More preferably, it is 0.5 mass%, and it is still more preferable that it is 0.1 mass%-0.5 mass%. When the content of the quantum dot phosphor is 0.01% by mass or more, sufficient light emission intensity tends to be obtained when the cured resin is irradiated with excitation light, and the content of the quantum dot phosphor is 1. When the content is 0% by mass or less, aggregation of the quantum dot phosphor tends to be suppressed.

  The cured resin according to the present disclosure includes a structural unit derived from a (meth) allyl compound. The content of the structural unit derived from the (meth) allyl compound in the cured resin is preferably 10% by mass to 50% by mass with respect to the total mass of the cured resin, and is 15% by mass to 45% by mass. More preferably, it is more preferably 20% by mass to 40% by mass. If the content of the structural unit derived from the (meth) allyl compound is 10% by mass or more, the heat resistance and heat-and-moisture resistance of the resin cured product tend to be further improved, and the structural unit derived from the (meth) allyl compound When the content is 50% by mass or less, the adhesiveness of the cured resin to the coating material or the like tends to be further improved.

  The cured resin according to the present disclosure includes a structural unit derived from a monofunctional thiol compound. The content of the structural unit derived from the monofunctional thiol compound in the cured resin is preferably 5% by mass to 30% by mass with respect to the total mass of the cured resin, and is 10% by mass to 30% by mass. More preferably, the content is more preferably 10% by mass to 20% by mass. When the content of the structural unit derived from the monofunctional thiol compound is 5% by mass or more, the adhesiveness of the cured resin to the coating material or the like tends to be further improved, and the content of the structural unit derived from the monofunctional thiol compound is included. When the rate is 30% by mass or less, the heat resistance and moist heat resistance of the resin cured product tend to be improved.

  The resin cured product according to the present disclosure may further include a structural unit derived from a compound having a polymerizable group other than the structural unit derived from the (meth) allyl compound and the structural unit derived from the monofunctional thiol compound. Specifically, a structural unit derived from a polyfunctional thiol compound, a structural unit derived from a (meth) acrylic compound, and the like can be given.

  The cured resin according to the present disclosure may include a structural unit derived from a polyfunctional thiol compound. The content of the structural unit derived from the polyfunctional thiol compound in the cured resin is preferably 40% by mass to 70% by mass, and 45% by mass to 70% by mass with respect to the total mass of the cured resin. More preferably, it is still more preferable that it is 45 mass%-65 mass%. When the content of the structural unit derived from the polyfunctional thiol compound is 40% by mass or more, the adhesiveness of the cured resin to the coating material or the like tends to be further improved, and the content of the structural unit derived from the polyfunctional thiol compound is included. When the rate is 70% by mass or less, the heat resistance and moist heat resistance of the resin cured product tend to be further improved.

  The cured resin according to the present disclosure may include a structural unit derived from a (meth) acrylic compound. The content of the structural unit derived from the (meth) acrylic compound in the cured resin is preferably 5.0% by mass to 9.0% by mass with respect to the total mass of the cured resin, and 5.8% by mass. % To 9.0% by mass is more preferable, and 5.8% to 8.5% by mass is even more preferable. When the content of the structural unit derived from the (meth) acrylic compound is 5.0% by mass or more, the adhesiveness of the resin cured product to the coating material or the like tends to be further improved, and derived from the (meth) acrylic compound When the content of the structural unit is 9.0% by mass or less, the heat resistance and heat-and-moisture resistance of the resin cured product tend to be further improved.

The cured resin according to the present disclosure preferably has a sulfide bond. It can be confirmed, for example, by Raman spectroscopy that the cured resin has a sulfide bond.
The sulfide bond may be formed, for example, by an ene-thiol reaction between a compound having an ethylenically unsaturated group and a thiol compound. Examples of the ene-thiol reaction include a reaction between a (meth) allyl compound and a thiol compound.

  The cured resin according to the present disclosure may further contain a dispersoid, a liquid medium, a polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion imparting agent, an antioxidant, and the like.

  The resin cured product according to the present disclosure has a loss tangent (tan δ) of 0.4 measured by dynamic viscoelasticity measurement at a frequency of 10 Hz and a temperature of 25 ° C. from the viewpoint of further improving adhesion to a coating material and the like described later. It is preferable that it is -1.5, It is more preferable that it is 0.6-1.5, It is still more preferable that it is 0.6-1.3. The loss tangent (tan δ) of the cured resin can be measured using a dynamic viscoelasticity measuring apparatus (for example, Rheometric Scientific, Solid Analyzer RSA-III).

The cured resin product according to the present disclosure has a storage elastic modulus (E ′) measured under conditions of a frequency of 10 Hz and a temperature of 25 ° C. from the viewpoint of further improving the adhesion to a coating material or the like, from 1 × 10 ⁷ Pa to 1 × 10. It is preferably ⁹ Pa, more preferably 1 × 10 ⁷ Pa to 5 × 10 ⁸ Pa, and still more preferably 4 × 10 ⁷ Pa to 5 × 10 ⁸ Pa. The storage elastic modulus (E ′) of the cured resin can be measured using a dynamic viscoelasticity measuring device (for example, Solid Analyzer RSA-III manufactured by Rheometric Scientific).

  In addition, the cured resin product according to the present disclosure preferably has a glass transition temperature (Tg) of 20 ° C. to 45 ° C. from the viewpoint of further improving adhesion, heat resistance, and moist heat resistance to a coating material and the like. It is more preferable that it is -40 degreeC, and it is still more preferable that it is 25-40 degreeC. The glass transition temperature (Tg) of the resin cured product can be measured using a dynamic viscoelasticity measuring device (for example, Solid Analyzer RSA-III manufactured by Rheometric Scientific).

  The shape of the resin cured product is not particularly limited, and examples thereof include a film shape and a lens shape. When applied to a backlight unit described later, the cured product is preferably in the form of a film.

When the resin cured product is in the form of a film, the average thickness of the resin cured product is, for example, preferably 50 μm to 200 μm, more preferably 50 μm to 150 μm, and still more preferably 80 μm to 150 μm. When the average thickness is 50 μm or more, the wavelength conversion efficiency tends to be further improved, and when the average thickness is 200 μm or less, the backlight unit tends to be thinner when applied to the backlight unit described later. is there.
The average thickness of the film-shaped resin cured product is obtained as an arithmetic average value of thicknesses at arbitrary three locations measured using a micrometer, for example.

(Coating material)
In the wavelength conversion member of the present disclosure, at least a part of the cured resin may be covered with a coating material. For example, when the cured resin is a film, one or both sides of the cured resin may be covered with a film-shaped coating material.

  The covering material preferably has a barrier property against at least one of oxygen and water, and more preferably has a barrier property against both oxygen and water, from the viewpoint of suppressing a decrease in light emission efficiency of the quantum dot phosphor. The covering material having a barrier property against at least one of oxygen and water is not particularly limited, and a known covering material such as a barrier film having an inorganic layer can be used.

When the coating material is in the form of a film, the average thickness of the coating material is preferably, for example, 100 μm to 150 μm, more preferably 100 μm to 140 μm, and still more preferably 100 μm to 135 μm. When the average thickness is 100 μm or more, functions such as barrier properties tend to be sufficient, and when the average thickness is 150 μm or less, a decrease in light transmittance tends to be suppressed.
The average thickness of the film-shaped coating material is determined in the same manner as the cured resin film.

The oxygen permeability of the coating material is, for example, preferably 0.5 mL / (m ² · 24 h · atm) or less, more preferably 0.3 mL / (m ² · 24 h · atm) or less, 0 More preferably, it is 1 mL / (m ² · 24 h · atm) or less. The oxygen permeability of the covering material can be measured using an oxygen permeability measuring device (for example, MOCON, OX-TRAN) under conditions of a temperature of 23 ° C. and a relative humidity of 65%.
Further, the water vapor transmission rate of the covering material is preferably 5 × 10 ⁻² g / (m ² · 24 h · Pa) or less, for example, and preferably 1 × 10 ⁻² g / (m ² · 24 h · Pa) or less. It is more preferable that it is 5 × 10 ⁻³ g / (m ² · 24 h · Pa) or less. The water vapor transmission rate of the coating material can be measured using a water vapor transmission rate measuring device (for example, MOCON, AQUATRAN) at a temperature of 40 ° C. and a relative humidity of 90%.

  The wavelength conversion member of the present disclosure preferably has a total light transmittance of 85% or less, more preferably 80% or less, and 76% or less from the viewpoint of further improving the light utilization efficiency. Further preferred. When the wavelength conversion member of this indication has a covering etc., a total light transmittance is a value of the whole wavelength conversion member.

  In the wavelength conversion member of the present disclosure, the haze is preferably 95% or more, more preferably 97% or more, and further preferably 99% or more from the viewpoint of further improving the light utilization efficiency.

The total light transmittance and haze are values measured as follows.
The wavelength conversion member is cut into dimensions of 50 mm width and 50 mm length to obtain a sample for evaluation. About the obtained sample for evaluation, using a turbidimeter (Nippon Denshoku Industries Co., Ltd., NDH-5000), the total light transmission was performed in accordance with the measuring method of JIS K7361-1: 1997 and JIS K7136: 2000. Measure the rate and diffuse transmittance. The haze of the evaluation sample is obtained according to the following formula.
Haze (%) = (Td / Tt) × 100
Td: diffuse transmittance Tt: total light transmittance

  When the wavelength conversion member of the present disclosure has a resin cured product and a coating material, the peel strength of the resin cured product with respect to the coating material is preferably 1.0 N / 25 mm or more, and 2.5 N / 25 mm or more. More preferably, it is 4.0 N / 25 mm or more.

The peel strength is a value measured as follows.
The wavelength conversion member is cut into a size of 25 mm in width and 100 mm in length to obtain a wavelength conversion member for evaluation. This wavelength conversion member for evaluation was laid down and installed in a tensile tester (Orientec Co., Ltd., RTC-1210), sandwiching one short side of the coating material, and at a tensile temperature of 300 mm / min under a temperature environment of 25 ° C. The covering material is peeled upward and the peel strength is measured.

  The wavelength conversion member of the present disclosure preferably has a relative light emission intensity of 0.30 to 0.45, more preferably 0.33 to 0.45, and preferably 0.33 to 0.40. Further preferred.

The relative light emission intensity is a value measured as follows.
The wavelength conversion member is cut into a dimension having a width of 45 mm and a length of 78 mm to obtain a wavelength conversion member for evaluation. Then, the backlight unit is taken out from a commercially available tablet PC (Amazon.com Inc, Kindle Fire HDX), and the evaluation wavelength conversion member is arranged in place of the wavelength conversion member in the backlight unit to produce an image display device. To do. Next, a spectral irradiance meter (UPRTek, MK-350) is arranged so that the detector is located at a position 25 mm from the outermost surface of the viewing surface of the image display device. Next, the image display device is turned on, the emission spectrum is measured by the spectral irradiance meter, and the relative emission intensity (RL) of the wavelength conversion member for evaluation is calculated according to the following formula.
Relative light emission intensity (RL) = Lb / La
La: emission peak intensity at a wavelength of 451 nm Lb: emission peak intensity at a wavelength of 530 nm

  The wavelength conversion member of the present disclosure preferably has a relative light emission intensity retention of 80% or more, more preferably 85% or more, and still more preferably 90% or more.

The relative light emission intensity retention is a value measured as follows.
After the wavelength conversion member is cut into a size of 100 mm in width and 100 mm in length, it is placed in a constant temperature and humidity chamber at 85 ° C. and 85% RH (relative humidity) and left for 150 hours. The emission intensity retention rate is calculated.
Relative emission intensity retention rate: (RLb / RLa) × 100
RLa: Initial relative light emission intensity RLb: Relative light emission intensity after 85 ° C. and 85% RH × 150 hours

(Other parts)
The wavelength conversion member of the present disclosure may further include other members other than the cured resin and the coating material.

  An example of a schematic configuration of the wavelength conversion member is shown in FIG. However, the wavelength conversion member of the present disclosure is not limited to the configuration of FIG. Moreover, the magnitude | size of the resin hardened | cured material layer and coating | covering material in FIG. 1 is notional, The relative relationship of a magnitude | size is not limited to this.

  A wavelength conversion member 10 illustrated in FIG. 1 includes a cured resin layer 11 that is in the form of a film, and film-shaped covering materials 12A and 12B that are provided on both surfaces of the cured resin layer 11. The types and average thicknesses of the covering material 12A and the covering material 12B may be the same or different.

  The wavelength conversion member having the configuration shown in FIG. 1 can be manufactured, for example, by the following method.

  First, a resin composition is provided on the surface of the film-like coating material 12A that is continuously conveyed to form a coating film (resin composition layer). The application method of 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 covering material 12B that is continuously conveyed is bonded onto the coating film.

  Next, the coating film is cured by irradiating the active energy ray from the side of the coating material that can transmit the active energy ray in the coating material 12A and the coating material 12B, thereby forming a cured resin layer. Then, the wavelength conversion member of the structure shown in FIG. 1 can be obtained by cutting out to a regular size.

  In addition, when neither the coating material 12A nor the coating material 12B can transmit the active energy ray, the active energy ray may be irradiated to the coating film before the coating material 12B is bonded to form a cured resin layer. Good.

<Backlight unit>
The backlight unit of the present disclosure includes the above-described wavelength conversion member of the present disclosure and a light source.

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

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

  Further, from the viewpoint of further improving color reproducibility, the half-value widths of the emission intensity peaks of blue light, green light, and red light emitted by the backlight unit are all preferably 80 nm or less, and 50 nm or less. More preferably, it is more preferably 40 nm or less, particularly preferably 30 nm or less, and particularly preferably 25 nm or less.

  As the light source of the backlight unit, for example, a light source that emits blue light having an emission center wavelength in a wavelength region of 430 nm to 480 nm can be used. Examples of the light source include an LED (Light Emitting Diode) and a laser. When using a light source that emits blue light, 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. Thereby, 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.

  Moreover, as a light source of a backlight unit, the light source which light-emits the ultraviolet light which has a light emission center wavelength in the wavelength range of 300 nm-430 nm can also be used, for example. Examples of the light source include an LED and a laser. When using a light source that emits ultraviolet light, the wavelength conversion member preferably includes a quantum dot phosphor B that emits blue light when excited by excitation light, together with the quantum dot phosphor R and the quantum dot phosphor G. Thereby, white light can be obtained from the red light, the green light, and the blue light emitted from the wavelength conversion member.

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

  An example of a schematic configuration of an edge light type backlight unit is shown in FIG. However, the backlight unit of the present disclosure is not limited to the configuration of FIG. Moreover, the magnitude | size of the member in FIG. 2 is notional, The relative relationship of the magnitude | size between members is not limited to this.

The backlight unit 20 shown in FIG. 2 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 A wavelength conversion member 10, a retroreflective member 23 disposed opposite to the light guide plate 22 via the wavelength conversion member 10, and a reflection plate 24 disposed opposite to the wavelength conversion member 10 via the light guide plate 22. . 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 is 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>
An image display device according to the present disclosure includes the above-described backlight unit according to the present disclosure. The image display device is not particularly limited, and examples thereof include a liquid crystal display device.

  An example of a schematic configuration of the liquid crystal display device is shown in FIG. However, the liquid crystal display device of the present disclosure is not limited to the configuration of FIG. Moreover, the magnitude | size of the member in FIG. 3 is notional, The relative relationship of the magnitude | size between members is not limited to this.

  A liquid crystal display device 30 shown in FIG. 3 includes a backlight unit 20 and a liquid crystal cell unit 31 disposed to face the backlight unit 20. The liquid crystal cell unit 31 has a configuration in which a liquid crystal cell 32 is disposed between a polarizing plate 33A and a polarizing plate 33B.

  The driving 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 Alignment) method, an IPS (In-Placed Switching) method, an OCB (Optically Filled Coding). The method etc. are mentioned.

<Resin composition for wavelength conversion member>
The resin composition for wavelength conversion members of the present disclosure (hereinafter also referred to as “resin composition”) includes a (meth) allyl compound, a monofunctional thiol compound, a photopolymerization initiator, and a quantum dot phosphor. . The resin composition of this indication may contain other ingredients other than the above-mentioned as needed. Examples of other components include compounds having a polymerizable group other than (meth) allyl compounds and monofunctional thiol compounds, dispersoids, and the like. The resin composition may further contain a liquid medium, a polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion promoter, an antioxidant, and the like.
When the resin composition of the present disclosure includes a quantum dot phosphor and a dispersoid, the dispersoid may contain the quantum dot phosphor from the viewpoint of excellent emission intensity, and the quantum dot phosphor in the dispersoid Are preferably dispersed.
When the resin composition of the present disclosure includes a quantum dot phosphor and a dispersoid, the present invention is not limited to a configuration in which all the quantum dot phosphors exist in the dispersoid, and at least one quantum dot phosphor outside the dispersoid. Or a part of at least one quantum dot phosphor may exist outside the dispersoid.

  Hereinafter, the components contained in the resin composition of the present disclosure will be described.

((Meth) allyl compound)
The resin composition of the present disclosure includes a (meth) allyl compound. The (meth) allyl compound may be a monofunctional (meth) allyl compound having one (meth) allyl group in one molecule, or a polyfunctional compound having two or more (meth) allyl groups in one molecule. It may be a functional (meth) allyl compound.
From the viewpoint of further improving the adhesion of the cured resin to the coating material or the like, the (meth) allyl compound preferably contains a polyfunctional (meth) allyl compound. The ratio of the polyfunctional (meth) allyl compound to the total mass of the (meth) allyl compound is, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and 100% by mass. Further preferred.

  Specific examples of monofunctional (meth) allyl compounds include (meth) allyl acetate, (meth) allyl n-propionate, (meth) allyl benzoate, (meth) allylphenyl acetate, (meth) allylphenoxyacetate, (meth) Examples include allyl methyl ether and (meth) allyl glycidyl ether.

  As the monofunctional (meth) allyl compound, commercially available products may be used. For example, neoallyl G (Osaka Soda Co., Ltd., allyl glycidyl ether), allyl phenyl acetate (Tokyo Chemical Industry Co., Ltd., allyl phenyl acetate) ) And the like.

  The polyfunctional (meth) allyl compound is preferably a compound having 2 to 4 (meth) allyl groups in the molecule from the viewpoint of heat resistance and heat and moisture resistance of the cured resin, More preferably, it is a compound having three (meth) allyl groups.

Specific examples of polyfunctional (meth) allyl compounds include di (meth) allyl benzenedicarboxylate, di (meth) allyl cyclohexanedicarboxylate, di (meth) allyl maleate, di (meth) allyl adipate, di (meth) Allyl phthalate, di (meth) allyl isophthalate, di (meth) allyl terephthalate, glycerin di (meth) allyl ether, trimethylolpropane di (meth) allyl ether, pentaerythritol di (meth) allyl ether, pentaerythritol tri (meth) ) Allyl ether, 1,3-di (meth) allyl-5-glycidyl isocyanurate, tri (meth) allyl cyanurate, tri (meth) allyl isocyanurate, tri (meth) allyl trimellitate, tetra (meth) allyl Pyromelitate, 1,3,4,6-te La (meth) allylglycoluril, 1,3,4,6-tetra (meth) allyl-3a-methylglycoluril, 1,3,4,6-tetra (meth) allyl-3a, 6a-dimethylglycoluril, etc. Is mentioned.
Among these, from the viewpoint of heat resistance and heat-and-moisture resistance of the cured resin, from tri (meth) allyl cyanurate, tri (meth) allyl isocyanurate, di (meth) allyl benzenedicarboxylate, and di (meth) allylcyclohexanedicarboxylate At least one selected from the group consisting of: tri (meth) allyl isocyanurate is more preferable.

  As the polyfunctional (meth) allyl compound, commercially available products may be used. For example, Thaik (Nippon Kasei Co., Ltd., triallyl isocyanurate), Neoallyl P-10 (Osaka Soda Co., Ltd., Pentaerythritol Trie) Allyl ether).

  As the (meth) allyl compound, one type may be used alone, two or more types may be used in combination, and a monofunctional (meth) allyl compound and a polyfunctional (meth) allyl compound may be used in combination.

  The content of the (meth) allyl compound in the resin composition is preferably, for example, 10% by mass to 50% by mass, and 15% by mass to 45% by mass with respect to the total mass of the resin composition. Is more preferable, and it is still more preferable that it is 20 mass%-40 mass%. When the content of the (meth) allyl compound is 10% by mass or more, the heat resistance and heat-and-moisture resistance of the resin cured product tend to be further improved, and the content of the (meth) allyl compound is 50% by mass or less. There is a tendency that the adhesion of the cured resin to the coating material and the like is further improved.

(Monofunctional thiol compound)
The resin composition of the present disclosure includes a monofunctional thiol compound.
As the monofunctional thiol compound, a primary thiol compound, a secondary thiol compound, and a tertiary thiol compound can be used. Especially, it is preferable that it is a primary thiol compound from a viewpoint of improving adhesiveness more.

  From the viewpoint of further improving the adhesion, the monofunctional thiol compound preferably has a molecular weight of 100 g / mol to 350 g / mol, more preferably 150 g / mol to 350 g / mol, and 150 g / mol to 300 g. More preferably, it is / mol.

  Examples of monofunctional thiol compounds include 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, and 3-mercapto. Examples include 3-methoxybutyl propionate, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, n-octyl-3-mercaptopropionate, and the like.

  As the monofunctional thiol compound, 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decane is used from the viewpoint of further improving the adhesion to the coating material of the cured resin and the heat and moisture resistance. Thiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, 3-methoxybutyl 3-mercaptopropionate, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, And n-octyl-3-mercaptopropionate are preferred, 3-methoxybutyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, and n-octyl-3-mercaptopropionate are more preferred, 3-Merka Topuropion acid 3-methoxybutyl and 2-ethylhexyl-3-mercaptopropionate is more preferable.

  As the monofunctional thiol compound, commercially available products may be used. For example, MBMP (SC Organic Chemical Co., Ltd., 3-methoxybutyl 3-mercaptopropionate), EHMP (SC Organic Chemical Co., Ltd., 2- And ethyl hexyl-3-mercaptopropionate) and NOMP (SC Organic Chemical Co., Ltd., n-octyl-3-mercaptopropionate).

  As the monofunctional thiol compound, one type may be used alone, or two or more types may be used in combination.

  The content of the monofunctional thiol compound in the resin composition is, for example, preferably 5% by mass to 30% by mass, and preferably 10% by mass to 30% by mass with respect to the total mass of the resin composition. More preferably, it is more preferably 10% by mass to 20% by mass. When the content of the monofunctional thiol compound is 5% by mass or more, the adhesiveness of the resin cured product to the coating material or the like tends to be further improved, and when the content of the monofunctional thiol compound is 30% by mass or less, There exists a tendency for the heat resistance and heat-and-moisture resistance of a cured resin to improve.

(Photopolymerization initiator)
The resin composition of the present disclosure includes a photopolymerization initiator. The photopolymerization initiator is not particularly limited, and examples thereof include compounds that generate radicals upon irradiation 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-hydroxycyclohexyl phenyl ketone, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 1- (4- ( 2-hydroxyethoxy) -phenyl) -2-hydroxy-2-methyl-1-propan-1-one, 2 Aromatic ketone compounds such as hydroxy-2-methyl-1-phenylpropan-1-one; quinone compounds such as alkylanthraquinone and phenanthrenequinone; benzoin compounds such as benzoin and alkylbenzoin; benzoins such as benzoin alkyl ether and benzoin phenyl ether Ether compounds; benzyl derivatives such as benzyldimethyl ketal; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole 2-mer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxy) Phenyl) -5-phenylimidazole 2,4,5-triarylimidazole dimers such as 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer; 9-phenylacridine, 1,7- (9, Acridine derivatives such as 9′-acridinyl) heptane; 1,2-octanedione 1- [4- (phenylthio) -2- (O-benzoyloxime)], ethanone 1- [9-ethyl-6- (2-methyl) Oxime ester compounds such as benzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime); coumarin compounds such as 7-diethylamino-4-methylcoumarin; thioxanthone compounds such as 2,4-diethylthioxanthone; 2,4,6-trimethylbenzoylphenylphosphinic acid ethyl, 2,4,6-trimethylbenzoyl-diphenyl-phosphine And acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyl-phenyl-ethoxy-phosphine oxide;
As a photoinitiator, 1 type may be used independently and 2 or more types may be used together.

  The photopolymerization initiator is preferably at least one selected from the group consisting of an acylphosphine oxide compound, an aromatic ketone compound, and an oxime ester compound from the viewpoint of curability, and includes an acylphosphine oxide compound and an aromatic ketone compound. At least one selected from the group consisting of these is more preferable, and acylphosphine oxide compounds are more preferable.

  The content of the photopolymerization initiator in the resin composition is preferably, for example, 0.1% by mass to 5% by mass, and 0.1% by mass to 3% by mass with respect to the total mass of the resin composition. It is more preferable that it is 0.5 mass%-1.5 mass%. If the content of the photopolymerization initiator is 0.1% by mass or more, the sensitivity of the resin composition tends to be sufficient, and if the content of the photopolymerization initiator is 5% by mass or less, the resin There exists a tendency for the influence on the hue of a composition and the fall of storage stability to be suppressed.

(Quantum dot phosphor)
The resin composition of the present disclosure includes a quantum dot phosphor. The kind, structure, and the like of the quantum dot phosphor are as described in the item of the wavelength conversion member of the present disclosure described above.

  The content of the quantum dot phosphor in the resin composition of the present disclosure is preferably 0.01% by mass to 1.0% by mass with respect to the total mass of the resin composition, for example, 0.05% by mass. It is more preferable that it is% -0.5 mass%, and it is still more preferable that it is 0.1 mass% -0.5 mass%. When the content of the quantum dot phosphor is 0.01% by mass or more, sufficient light emission intensity tends to be obtained when the cured resin is irradiated with excitation light, and the content of the quantum dot phosphor is 1. When the content is 0% by mass or less, aggregation of the quantum dot phosphor tends to be suppressed.

  The resin composition of the present disclosure may further include a compound having a polymerizable group other than the (meth) allyl compound and the monofunctional thiol compound. For example, a (meth) acryl compound, a polyfunctional thiol compound, etc. are mentioned.

((Meth) acrylic compound)
The resin composition of the present disclosure may further include a (meth) acryl compound.
The (meth) acrylic compound may be a monofunctional (meth) acrylic compound having one (meth) acryloyl group in one molecule, or a polyfunctional compound having two or more (meth) acryloyl groups in one molecule. It may be a functional (meth) acryl compound.
As the (meth) acrylic compound, one type may be used alone, two or more types may be used in combination, and a monofunctional (meth) acrylic compound and a polyfunctional (meth) acrylic compound may be used in combination.

  Specific examples of monofunctional (meth) acrylic compounds include: (meth) acrylic acid; methyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth ) Acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, etc. alkyl (meth) acrylate having 1 to 18 carbon atoms; benzyl (meth) acrylate, phenoxyethyl ( (Meth) acrylate compounds having an aromatic ring such as (meth) acrylate; aminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate; cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate (Meth) acrylate compounds having an alicyclic ring such as isobornyl (meth) acrylate and methylene oxide-added cyclodecatriene (meth) acrylate; (meth) acrylate compounds having a heterocyclic ring such as (meth) acryloylmorpholine; heptadecafluorodecyl ( Fluorinated alkyl (meth) acrylates such as (meth) acrylate; (meth) acrylate compounds having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; (Meth) acrylate compounds having an isocyanate group such as 2- (2- (meth) acryloyloxyethyloxy) ethyl isocyanate and 2- (meth) acryloyloxyethyl isocyanate; N, N-dimethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide (Meth) acrylamide compounds such as;

  As the monofunctional (meth) acrylic compound, a commercially available product may be used. For example, ACMO (KJ Chemicals Co., Ltd., acryloylmorpholine), IBXA (Osaka Organic Chemical Co., Ltd., isobornyl acrylate), And dicyclopentanyl acrylate (Hitachi Chemical Co., Ltd., FA-513AS).

  The polyfunctional (meth) acrylic compound is preferably a compound having 2 to 4 (meth) acryloyl groups in the molecule from the viewpoint of the heat resistance and heat and humidity resistance of the cured resin. A compound having three (meth) acryloyl groups is more preferable.

Specific examples of the polyfunctional (meth) acrylic compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, and the like. Alkylene glycol di (meth) acrylate; trimethylolpropane tri (meth) acrylate, tris (2- (meth) acryloyloxyethyl) isocyanurate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate ) Acrylate compounds; tetra (meth) acrylate compounds such as trimethylolpropane tetra (meth) acrylate and pentaerythritol tetra (meth) acrylate;
Of these, tris (2- (meth) acryloyloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, and trimethylolpropane tri (meth) acrylate are preferable from the viewpoint of heat resistance and heat and moisture resistance of the cured resin. (2- (Meth) acryloyloxyethyl) isocyanurate and pentaerythritol tetra (meth) acrylate are more preferred, and tris (2- (meth) acryloyloxyethyl) isocyanurate is still more preferred.

  As the polyfunctional (meth) acrylic compound, a commercially available product may be used. For example, Fanacryl FA-731A (Hitachi Chemical Co., Ltd., Tris (2-acryloyloxyethyl) isocyanurate), A-TMPT (Shin Nakamura Chemical Co., Ltd., trimethylolpropane triacrylate), A-TMMT (Shin Nakamura Chemical Co., Ltd., pentaerythritol tetraacrylate) and the like.

  The (meth) acrylic compound may contain a monofunctional (meth) acrylate compound having an alicyclic ring from the viewpoint of further improving the heat resistance and heat-and-moisture resistance of the cured resin, and isobornyl (meth) acrylate, di Cyclopentanyl (meth) acrylate etc. may be included, Preferably isobornyl (meth) acrylate may be included.

  When the resin composition contains a (meth) acrylic compound, the content of the (meth) acrylic compound in the resin composition is, for example, 8.0% by mass to 20.0% by mass with respect to the total mass of the resin composition. % May be sufficient, 9.0 mass%-17.0 mass% may be sufficient, and 10.0 mass%-14.0 mass% may be sufficient. When the content of the (meth) acrylic compound is 8.0% by mass or more, the storage stability of the resin composition and the adhesiveness of the cured resin to the coating material tend to be further improved, and the (meth) acrylic compound When the content of is 20.0% by mass or less, the heat resistance and moist heat resistance of the cured resin product tend to be improved.

(Polyfunctional thiol compound)
The resin composition of the present disclosure may further contain a polyfunctional thiol compound. Thereby, it exists in the tendency which the adhesiveness, heat resistance, and heat-and-moisture resistance of the resin cured material with respect to a coating | covering material etc. improve more.

  The polyfunctional thiol compound is preferably a compound having 2 to 6 thiol groups in the molecule, and more preferably a compound having 3 or 4 thiol groups in the molecule.

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- Propylene 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, trimethylolpropane tris (3-mercaptopro) Pionate , Trimethylolpropane tris (3-mercaptobutyrate), trimethylolpropane tris (3-mercaptoisobutyrate), trimethylolpropane tris (2-mercaptoisobutyrate), trimethylolpropane tristhioglycolate, tris- [ (3-mercaptopropionyloxy) -ethyl] -isocyanurate, trimethylolethane tris (3-mercaptobutyrate), pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptobutyrate), penta Erythritol tetrakis (3-mercaptoisobutyrate), pentaerythritol tetrakis (2-mercaptoisobutyrate), dipentaerythritol hexakis (3-mercaptop) Pionate), dipentaerythritol hexakis (2-mercaptopropionate), dipentaerythritol hexakis (3-mercaptobutyrate), dipentaerythritol hexakis (3-mercaptoisobutyrate), dipentaerythritol hexakis ( 2-mercaptoisobutyrate), pentaerythritol tetrakisthioglycolate, dipentaerythritol hexakisthioglycolate and the like.
Among these, pentaerythritol tetrakis (3-mercaptopropionate) and pentaerythritol tetrakis (3-mercaptobutyrate) are preferable, and pentaerythritol tetrakis (3-mercaptopropionate) is more preferable.

  As the polyfunctional thiol compound, commercially available products may be used. For example, PEMP (SC Organic Chemical Co., Ltd., pentaerythritol tetrakis (3-mercaptopropionate)), Karenz MT PE1 (Showa Denko Co., Ltd.) , Pentaerythritol tetrakis (3-mercaptobutyrate)), TPMB (Showa Denko KK, trimethylolpropane tris (3-mercaptobutyrate)) and the like.

  As a polyfunctional thiol compound, 1 type may be used independently and 2 or more types may be used together.

  Moreover, as a polyfunctional thiol compound, you may use the thioether oligomer which reacted with the (meth) acryl compound previously.

  The thioether oligomer can be obtained by subjecting a polyfunctional thiol compound and a (meth) acrylic compound to an addition reaction in the presence of a polymerization initiator. The ratio of the number of equivalents of thiol groups of the polyfunctional thiol compound to the number of equivalents of (meth) acryloyl groups of the (meth) acrylic compound (number of equivalents of thiol group / number of equivalents of (meth) acryloyl group) is, for example, 3.0. To 3.3, more preferably 3.0 to 3.2, and even more preferably 3.05 to 3.15.

  The weight average molecular weight of the thioether oligomer is, for example, preferably 3,000 to 10,000, more preferably 3,000 to 8,000, and still more preferably 4,000 to 6,000. .

The weight average molecular weight of the thiol ether oligomer is a value determined by conversion using a standard polystyrene calibration curve using gel permeation chromatography with the following apparatus and measurement conditions. In preparing the calibration curve, 5 sample sets (PStQuick MP-H, PStQuick B [Tosoh Corporation, trade name]) are used as standard polystyrene.
Apparatus: High-speed GPC apparatus HLC-8320GPC (detector: differential refractometer) (Tosoh Corporation, trade name)
Solvent: Tetrahydrofuran (THF)
Column: Column TSKGEL SuperMultipore HZ-H (trade name, manufactured by Tosoh Corporation)
Column size: Column length 15 cm, column inner diameter 4.6 mm
Measurement temperature: 40 ° C
Flow rate: 0.35 mL / min Sample concentration: 10 mg / THF 5 mL
Injection volume: 20 μL

  The thiol equivalent of the thioether oligomer is, for example, preferably 200 g / eq to 400 g / eq, more preferably 250 g / eq to 350 g / eq, and further preferably 250 g / eq to 270 g / eq. preferable.

The thiol equivalent of the thioether oligomer can be measured by the following iodine titration method.
0.2 g of a measurement sample is precisely weighed, and 20 mL of chloroform is added thereto to obtain a sample solution. Using 2075 g of pure starch dissolved in 30 g of pure water as a starch indicator, add 20 mL of pure water, 10 mL of isopropyl alcohol, and 1 mL of starch indicator, and stir with a stirrer. The iodine solution is dropped and the end point is the point at which the chloroform layer is green. At this time, the value given by the following formula is the thiol equivalent of the measurement sample.
Thiol equivalent (g / eq) = mass of measurement sample (g) × 10000 / titration amount of iodine solution (mL) × factor of iodine solution

  Among thioether oligomers, pentaerythritol tetrakis (3-mercaptopropionate) and tris (2- (meth) acryloyloxyethyl) isocyanurate are used from the viewpoint of further improving the optical properties, heat resistance, and moist heat resistance of the cured resin. A thioether oligomer obtained by addition polymerization of is preferred.

  When the resin composition contains a polyfunctional thiol compound, the content of the polyfunctional thiol compound in the resin composition is preferably, for example, 40% by mass to 70% by mass with respect to the total mass of the resin composition. More preferably, it is 45 mass%-70 mass%, and it is still more preferable that it is 45 mass%-65 mass%. When the content of the polyfunctional thiol compound is 40% by mass or more, the adhesiveness of the resin cured product to the coating material or the like tends to be further improved, and when the content of the thiol compound is 70% by mass or less, the resin is cured. There exists a tendency for the heat resistance and heat-and-moisture resistance of a thing to improve more.

(Liquid medium)
The resin composition of the present disclosure may further include a liquid medium. A liquid medium means a medium in a liquid state at room temperature (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, Ketone solvents such as dipropyl ketone, diisobutyl ketone, trimethylnonanone, cyclohexanone, cyclopentanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone; diethyl ether, methyl ethyl ether, methyl-n-propyl ether, diisopropyl Ether, tetrahydrofuran, methyltetrahydrofuran, dioxane, dimethyldioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol Rudi-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, triethylene glycol methyl ethyl ether, triethylene glycol methyl n-butyl ether, triethylene glycol di-n-butyl ether , Triethyleneglycol Rumethyl-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, dipropylene Glycol 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, tetra Ether solvents such as propylene glycol methyl-n-hexyl ether; carbonate solvents such as propylene carbonate, ethylene carbonate and diethyl carbonate; methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec sec -Butyl, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 2- (2-butoxyethoxy) ethyl acetate, benzyl acetate, cyclohexyl acetate, Methyl cyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetoacetate, acetic acid diethylene glycol methyl ether, acetic acid diethylene glycol monoethyl ether, acetic acid dipropylene glycol methyl ether , Dipropylene glycol ethyl ether acetate, 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-amyl lactate, 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, Ester solvents such as propylene glycol propyl ether acetate, γ-butyrolactone, γ-valerolactone; acetonitrile, N-methyl Aprotic polarities such as rupyrrolidinone, N-ethylpyrrolidinone, N-propylpyrrolidinone, N-butylpyrrolidinone, N-hexylpyrrolidinone, N-cyclohexylpyrrolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide Solvent: 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-oct Tanol, n-nonyl alcohol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, cyclohexanol, methylcyclohexanol, benzyl alcohol, ethylene glycol, 1,2- Alcohol solvents such as propylene glycol, 1,3-butylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, 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 solvents; terpene solvents such as terpinene, terpineol, myrcene, alloocimene, limonene, dipentene, pinene, carvone, oximene, and ferrandylene; straight silicone oils such as dimethyl silicone oil, methylphenyl silicone oil, and methylhydrogen silicone oil; Amino-modified silicone oil, phenol-modified silicone oil, EPO Si-modified silicone oil, carboxy-modified silicone oil, 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 Modified silicone oil such as silicone oil, higher fatty acid modified silicone oil, fluorine modified silicone oil; glycerin fatty acid ester; surfactant polyol; butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid , Carbons such as dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanoic acid, icosanoic acid, eicosenoic acid And saturated aliphatic monocarboxylic acids having 4 or more; unsaturated aliphatic monocarboxylic acids having 8 or more carbon atoms such as oleic acid, elaidic acid, linoleic acid, and palmitoleic acid. The resin composition of the present disclosure may contain one type of liquid medium alone, or may contain two or more types of liquid media.

The liquid medium may be used as a dispersoid for dispersing the quantum dot phosphor. When the liquid medium is used as a dispersoid, it is not limited as long as it can be dispersed in the resin composition, and straight silicone oil, modified silicone oil, glycerin fatty acid ester, surface active polyol, and the like can be used. Among these, modified silicone oil is preferable. Among the modified silicone oils, amino-modified silicone oils are preferable from the viewpoint of light diffusibility and dispersibility of the quantum dot phosphor.
When using a liquid medium as a dispersoid, one type may be used independently and two or more types may be used together.

  When the resin composition includes a liquid medium, the content of the liquid medium in the resin composition is preferably, for example, 1% by mass to 10% by mass with respect to the total mass of the resin composition, and 4% by mass. More preferably, it is 10 mass%, More preferably, it is 4 mass%-7 mass%.

  When the resin composition includes a liquid medium, the total content of the quantum dot phosphor and the liquid medium in the resin composition is, for example, 1% by mass to 10% by mass with respect to the total mass of the resin composition. 3 mass%-7 mass% may be sufficient, and 5 mass%-7 mass% may be sufficient.

(Other ingredients)
The resin composition of the present disclosure may further contain other components such as a polymerization inhibitor, a silane coupling agent, a surfactant, an adhesion imparting agent, and an antioxidant. The resin composition of the present disclosure may include one type of each of the other components, or may include two or more types.

(Method for preparing resin composition)
The resin composition of the present disclosure includes a (meth) allyl compound, a monofunctional thiol compound, a photopolymerization initiator, a quantum dot phosphor, and, if necessary, a (meth) acryl compound, a polyfunctional thiol compound, a dispersoid, and a liquid medium It can prepare by mixing other components, such as, by a conventional method. The quantum dot phosphor is preferably mixed while being dispersed in a liquid medium.

<Hardened resin>
The cured resin product of the present disclosure is a cured product of the above-described resin composition of the present disclosure. The cured resin may be used for the wavelength conversion member of the present disclosure described above.
The resin cured product of the present disclosure may be one obtained by curing one type of resin composition, or may be one obtained by curing two or more types of resin compositions. For example, when the cured resin is a film, the cured resin is composed of a first cured resin layer obtained by curing a resin composition containing the first quantum dot phosphor, and the first quantum dot phosphor. It may be laminated with a second cured resin layer obtained by curing a resin composition containing second quantum dot phosphors having different emission characteristics.

The cured resin product can be obtained by forming a coating film, a molded product or the like of the resin composition, performing a drying treatment as necessary, and then irradiating active energy rays such as ultraviolet rays. The wavelength and irradiation amount of the active energy ray can be appropriately set according to the composition of the resin composition. In some embodiments, irradiating ultraviolet rays having a wavelength of 280nm~400nm at dose of ^{100mJ / cm 2 ~5000mJ / cm 2} . Examples of the ultraviolet light source include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, a black light lamp, and a microwave-excited mercury lamp.

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

<Synthesis Example 1>
Weighed 174.0 g of pentaerythritol tetrakis (3-mercaptopropionate) (SC Organic Chemical Co., PEMP) into a reaction vessel equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a vacuum pipe, and a rotational speed of 200 While stirring at times / minute, the inside of the reaction vessel was depressurized using a vacuum pump and held for 30 minutes. Thereafter, 26.0 g of tris (2-acryloyloxyethyl) isocyanurate (Hitachi Kasei Co., Ltd., Fanacryl FA-731A) dissolved in advance by heating at 55 ° C. to 65 ° C. was mixed and stirred for 30 minutes. Subsequently, 0.25 g of triethylamine was added as a catalyst and reacted for 2 hours. The reaction was terminated after confirming that the absorption peak of the acryloyl group had disappeared by infrared spectroscopic analysis, and a thioether oligomer (weight average molecular weight: 4600) was obtained.

In addition, a weight average molecular weight is the value determined by converting using the calibration curve of a standard polystyrene by the following apparatus and measurement conditions using a gel permeation chromatography. In preparing the calibration curve, 5 sample sets (PStQuick MP-H, PStQuick B [Tosoh Corporation, trade name]) were used as standard polystyrene.
Apparatus: High-speed GPC apparatus HLC-8320GPC (detector: differential refractometer) (Tosoh Corporation, trade name)
Solvent: Tetrahydrofuran (THF)
Column: Column TSKGEL SuperMultipore HZ-H (Tosoh Corporation, trade name)
Column size: Column length 15 cm, column inner diameter 4.6 mm
Measurement temperature: 40 ° C
Flow rate: 0.35 mL / min Sample concentration: 10 mg / THF 5 mL
Injection volume: 20 μL

<Examples 1 to 4 and Comparative Examples 1 and 2>
(Preparation of resin composition)
The resin compositions of Examples 1 to 4 and Comparative Examples 1 and 2 were prepared by mixing the components shown in Table 1 in the blending amounts (unit: parts by mass) shown in the same table. “-” In Table 1 means not blended.
In addition, as the (meth) allyl compound, triallyl isocyanurate (Nippon Kasei Co., Ltd., Taik) was used. Monofunctional thiol compounds include 3-methoxybutyl 3-mercaptopropionate (SC Organic Chemical Co., Ltd., MBMP, molecular weight: 192.30 g / mol) and 2-ethylhexyl-3-mercaptopropionate (SC organic chemistry). Co., Ltd., EHMP, molecular weight: 218.35 g / mol) was used. As the photopolymerization initiator, ethyl 2,4,6-trimethylbenzoylphenylphosphinate (DKSH Japan Ltd., LUNACURE TPO-L) was used. Further, as the quantum dot phosphor, a CdSe / ZnS (core / shell) dispersion (Nanosys, Gen2 QD Concentrate) was used.

(Manufacture of wavelength conversion member)
Each resin composition obtained above was applied onto a 135 μm thick barrier film (Toppan Printing Co., Ltd., model number PJR135-B381-H11) as a coating material to form a coating film. A 135 μm thick barrier film (Toppan Printing Co., Ltd., model number PJR135-B381-H11), which is a coating material, is bonded onto this coating film, and irradiated with ultraviolet rays using an ultraviolet irradiation device (eye graphics Co., Ltd.). : 1000 mJ / cm ² ), the wavelength conversion member in which the coating material was disposed on both surfaces of the cured resin layer was obtained.

<Evaluation>
Using the wavelength conversion members obtained in Examples 1 to 4 and Comparative Examples 1 and 2, the following evaluation items were measured and evaluated. The results are shown in Table 2.

(Total light transmittance and haze)
Each wavelength conversion member obtained above was cut into a size of 50 mm in width and 50 mm in length to obtain a sample for evaluation. And using a turbidimeter (Nippon Denshoku Industries Co., Ltd., NDH-5000), based on the measurement method of JIS K7361-1: 1997 and JIS K7136: 2000, the total light transmittance of the sample for evaluation and Haze was measured. In addition, the haze of the sample for evaluation was calculated | required according to the following formula.
Haze (%) = (Td / Tt) × 100
Td: diffuse transmittance Tt: total light transmittance

(Adhesion)
Each wavelength conversion member obtained above was cut into dimensions of 25 mm in width and 100 mm in length to obtain a wavelength conversion member for evaluation. This wavelength conversion member for evaluation was laid down and installed in a tensile tester (Orientec Co., Ltd., RTC-1210), sandwiching one short side of the coating material, and at a tensile temperature of 300 mm / min under a temperature environment of 25 ° C. The coating material was peeled upward and the peel strength was measured.

(Relative emission intensity)
Each wavelength conversion member obtained above was cut into dimensions of 45 mm in width and 78 mm in length to obtain a wavelength conversion member for evaluation. Then, the backlight unit is taken out from a commercially available tablet PC (Amazon.com Inc, Kindle Fire HDX), and the evaluation wavelength conversion member is arranged in place of the wavelength conversion member in the backlight unit to produce an image display device. did. Next, a spectral irradiance meter (UPRTek, MK-350) was placed so that the detector was positioned 25 mm from the outermost surface of the viewing surface of the image display device. Next, the image display device was turned on, the emission spectrum was measured with the spectral irradiance meter, and the relative emission intensity (RL) of the wavelength conversion member for evaluation was calculated according to the following formula.
Relative light emission intensity (RL) = Lb / La
La: emission peak intensity at a wavelength of 451 nm Lb: emission peak intensity at a wavelength of 530 nm

(Moisture and heat resistance)
Each wavelength conversion member obtained above is cut into dimensions of 100 mm in width and 100 mm in length, then placed in a constant temperature and humidity chamber at 85 ° C. and 85% RH (relative humidity), and left to stand for 150 hours. The relative light emission intensity retention rate of the wavelength conversion member was calculated according to
Relative emission intensity retention rate: (RLb / RLa) × 100
RLa: Initial relative light emission intensity RLb: Relative light emission intensity after 85 ° C. and 85% RH × 150 hours And the heat-and-moisture resistance of each wavelength conversion member was evaluated according to the following evaluation criteria.
-Evaluation criteria-
A: Relative emission intensity retention: 90% or more B: Relative emission intensity retention: 80% or more and less than 90% C: Relative emission intensity retention: less than 80%

(Storage elastic modulus (E ') and glass transition temperature)
The barrier film of each wavelength conversion member obtained above was peeled off and cut into dimensions of 5 mm in width and 40 mm in length to obtain a cured resin product for evaluation. Then, using a wide-range dynamic viscoelasticity measuring apparatus (Rheometric Scientific, Solid Analyzer RSA-III), “tensile mode, distance between chucks: 25 mm, frequency: 10 Hz, measurement temperature range: −20 ° C. to 100 ° C., ascending Under the condition of “temperature rate: 5 ° C./min”, the storage elastic modulus (E ′) and loss elastic modulus (E ″) of the cured resin for evaluation at a temperature of 25 ° C. are measured, and the loss tangent (tan δ) is determined from the ratio. Asked. Further, the glass transition temperature (Tg) was determined from the temperature at the peak top of the loss tangent (tan δ).

  As can be seen from Table 2, it can be seen that the wavelength conversion members of Examples 1 to 4 are excellent in the adhesiveness of the cured resin without impairing the moist heat resistance.

DESCRIPTION OF SYMBOLS 10 Wavelength conversion member 11 Resin hardened material layer 12A Coating material 12B Coating material 20 Backlight unit 21 Light source 22 Light guide plate 23 Retroreflective member 24 Reflection plate 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 (20)

  A wavelength conversion member comprising a resin cured product comprising a structural unit derived from a (meth) allyl compound, a structural unit derived from a monofunctional thiol compound, and a quantum dot phosphor.   The wavelength conversion member according to claim 1, wherein the cured resin further includes a structural unit derived from a polyfunctional thiol.   The wavelength conversion member according to claim 1, wherein the cured resin has a sulfide bond.   The wavelength conversion member according to claim 1, wherein the monofunctional thiol compound has a molecular weight of 100 g / mol to 350 g / mol.   The monofunctional thiol compound is 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, 3-mercaptopropionic acid. At least one selected from the group consisting of 3-methoxybutyl, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, and n-octyl-3-mercaptopropionate The wavelength conversion member according to any one of claims 1 to 4, which is a seed.   The wavelength conversion member according to claim 1, wherein the cured resin has a glass transition temperature (Tg) of 20 ° C. to 45 ° C. 6. The storage elastic modulus (E ') of the resin cured product measured by dynamic viscoelasticity measurement at a frequency of 10 Hz and a temperature of 25 ° C is 1 x 10 ⁷ Pa to 1 x 10 ⁹ Pa. 1 to 6 The wavelength conversion member according to any one of the above.   The wavelength conversion member according to claim 1, wherein the cured resin is in the form of a film.   The wavelength conversion member according to claim 1, further comprising a covering material that covers at least a part of the cured resin.   The wavelength conversion member according to claim 9, wherein the coating material has a barrier property against at least one of oxygen and water.   The wavelength conversion member according to claim 9 or 10, wherein a peel strength of the resin cured product with respect to the coating material is 4 N / 25 mm or more.   The wavelength conversion member according to any one of claims 1 to 11, wherein the quantum dot phosphor includes a compound containing at least one selected from the group consisting of Cd and In.   A backlight unit comprising the wavelength conversion member according to any one of claims 1 to 12 and a light source.   An image display device comprising the backlight unit according to claim 13.   A resin composition for a wavelength conversion member, comprising a (meth) allyl compound, a monofunctional thiol compound, a photopolymerization initiator, and a quantum dot phosphor.   The resin composition for a wavelength conversion member according to claim 15, wherein the monofunctional thiol compound has a molecular weight of 100 g / mol to 350 g / mol.   The monofunctional thiol compound is 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, 3-mercaptopropionic acid. At least one selected from the group consisting of 3-methoxybutyl, octyl 3-mercaptopropionate, tridecyl 3-mercaptopropionate, 2-ethylhexyl-3-mercaptopropionate, and n-octyl-3-mercaptopropionate The resin composition for wavelength conversion members according to claim 15 or 16, which is a seed.   The resin composition for wavelength conversion members according to any one of claims 15 to 17, further comprising a polyfunctional thiol compound.   The said quantum dot fluorescent substance is a resin composition for wavelength conversion members of any one of Claims 15-18 containing the compound containing at least one selected from the group which consists of Cd and In.   A cured resin, which is a cured product of the wavelength conversion member resin composition according to any one of claims 15 to 19.