JP6230974B2 - Light conversion member, backlight unit, liquid crystal display device, and method of manufacturing light conversion member - Google Patents

Description

The present invention relates to a light conversion member and a method for manufacturing the same, and more particularly to a light conversion member capable of increasing front luminance when incorporated in a liquid crystal display device and having excellent light resistance and a method for manufacturing the same. It is.
The present invention further relates to a backlight unit including the light conversion member and a liquid crystal display device including the backlight unit.

  Flat panel displays such as liquid crystal display devices (hereinafter also referred to as LCDs) have low power consumption and are increasingly used as space-saving image display devices year by year. The liquid crystal display device is composed of at least a backlight and a liquid crystal cell, and usually further includes members such as a backlight side polarizing plate and a viewing side polarizing plate.

  In the flat panel display market, color reproducibility is improving as LCD performance improvement. In this regard, in recent years, quantum dots (also referred to as Quantum Dot, QD, or quantum dots) have attracted attention as light emitting materials (see Patent Document 1). For example, when excitation light enters a light conversion member including quantum dots from a backlight, the quantum dots are excited and emit fluorescence. Here, by using quantum dots having different emission characteristics, white light can be realized by emitting bright line light of red light, green light, and blue light. Since the fluorescence due to the quantum dots has a small half-value width, the white light obtained has high brightness and excellent color reproducibility. With the progress of the three-wavelength light source technology using such quantum dots, the color gamut has been expanded from 72% to 100% of the current TV standard (FHD, NTSC (National Television System Committee)).

US2012 / 0113672A1

  The quantum dot has a problem that when it comes into contact with oxygen, the light emission intensity decreases due to a photo-oxidation reaction (low light resistance). In this regard, Patent Document 1 proposes laminating a barrier layer on a film containing quantum dots in order to protect the quantum dots from oxygen and the like.

  On the other hand, however, if the barrier layer is provided and the light transmittance (visible light transmittance) of the light conversion member is reduced, the utilization efficiency of the light emitted by the quantum dots is reduced, and the liquid crystal display When incorporated in the device, the front luminance is lowered. As a result, the advantage of quantum dots that high brightness white light can be obtained cannot be fully utilized. Therefore, it is desired that the barrier layer provided on the light conversion member including the quantum dots has improved light resistance without lowering the front luminance when incorporated in a liquid crystal display device. The barrier layer described in Patent Document 1 requires further improvement in this respect.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a light conversion member including quantum dots, which can increase front luminance when incorporated in a liquid crystal display device and has excellent light resistance.

As a result of intensive studies to achieve the above object, the present inventors have obtained the following new knowledge.
Patent Document 1 exemplifies silicon oxide as a specific example of the barrier layer. An inorganic layer formed from an inorganic material such as silicon oxide is excellent as a barrier property, particularly an oxygen barrier property, and thus is suitable as a barrier layer for suppressing the photooxidation reaction of quantum dots.
On the other hand, in a light conversion member including quantum dots, the quantum dots are usually dispersed in an organic layer mainly composed of a resin. The low adhesion between the organic layer and the inorganic layer makes it difficult for the present inventors to provide a light conversion member capable of achieving both high front luminance and light resistance when incorporated in a liquid crystal display device. As a result of further studies, the present invention has been completed.

One embodiment of the present invention provides:
A light conversion member having a light conversion layer including quantum dots that are excited by incident excitation light and emit fluorescence.
Having an adjacent inorganic layer in direct contact with the light conversion layer, and
The light conversion layer includes a quantum dot in an organic matrix, and a light conversion member further including an adhesion improving agent,
About.
Another aspect of the present invention is a light conversion member having a light conversion layer including quantum dots that are excited by incident excitation light and emit fluorescence.
Having an adhesion improving layer in direct contact with the light conversion layer, and having an inorganic layer in direct contact with the adhesion improving layer, and
The adhesion improving layer contains an adhesion improving agent, and the adhesion improving layer further has a mixed region of the adhesion improving layer component and the light converting layer component on the surface of the light converting layer,
About.

  In one aspect, the adhesion improver includes a polymerizable compound having in its molecule at least one of a structure selected from an organometallic coupling agent, a polymerizable compound having a phosphate group, and a urethane bond, a urea bond, and an isocyanuric ring. It is at least one selected from compounds.

  In one mode, the above-mentioned light conversion member further has one or more layers chosen from the group which consists of an inorganic layer and an organic layer in the field opposite to the above-mentioned light conversion layer side.

  In one mode, the above-mentioned light conversion member further has one or more layers chosen from the group which consists of an inorganic layer and an organic layer in the field opposite to the above-mentioned inorganic layer side.

  In one aspect, the inorganic layer consists essentially of silicon nitride.

  In one aspect, the organic matrix is a polymer of a monofunctional (meth) acrylate monomer and a polyfunctional (meth) acrylate monomer.

  In one embodiment, the monofunctional (meth) acrylate monomer has a long-chain alkyl group having 4 to 30 carbon atoms.

In one aspect, the quantum dots are
Quantum dots (A) having an emission center wavelength in a wavelength band ranging from 600 nm to 680 nm,
A quantum dot (B) having an emission center wavelength in a wavelength band in the range of 500 nm to 600 nm, and a quantum dot (C) having an emission center wavelength in a wavelength band of 400 nm to 500 nm,
Is at least one selected from the group consisting of

In one embodiment, the above light conversion member has an oxygen transmission rate of 1.00 cm ³ / (m ² · day · atm) or less.

A further aspect of the invention provides:
The light conversion member described above;
A light source;
Including at least a backlight unit,
About.

In one aspect, the backlight unit described above is
Blue light having an emission center wavelength in a wavelength band of 430 to 480 nm and a peak of emission intensity having a half width of 100 nm or less;
Green light having an emission center wavelength in a wavelength band of 500 to 600 nm and a peak of emission intensity having a half width of 100 nm or less;
Red light having an emission center wavelength in a wavelength band of 600 to 680 nm and a peak of emission intensity having a half-value width of 100 nm or less;
Is emitted.

  In one embodiment, the light source has an emission center wavelength in a wavelength band of 380 to 480 nm.

In one aspect, the above-described backlight unit further includes a light guide plate, and has the light conversion member on a path of light emitted from the light guide plate.
In another aspect, the backlight unit includes the light conversion member between the light guide plate and the light source.

A further aspect of the invention provides:
The above backlight unit;
A liquid crystal cell;
A liquid crystal display device comprising at least
About.

A further aspect of the invention provides:
Formation of a light conversion layer containing quantum dots and a polymerizable compound on the surface of the inorganic layer of the first barrier film containing at least the inorganic layer, or on the surface of the adhesion improving layer optionally provided on the surface of the inorganic layer Providing a polymerizable composition for,
Forming the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film, A method for producing the light conversion member,
About.

In one aspect, before the step of forming the light conversion layer, the light conversion layer is formed by providing a second barrier film on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film. A step of disposing a polymer composition for contact with a surface opposite to the side on which the first barrier film is provided,
In the step of forming the light conversion layer, the polymerizable composition for forming the light conversion layer is polymerized in a state where the first barrier film, the light conversion layer, and the second barrier film are laminated in this order. In this step, the light conversion layer is formed.

In one aspect | mode, the process of heating the polymeric composition for the said light conversion layer formation is included before the process of forming the said light conversion layer.
In one aspect, the polymerizable composition for forming the light conversion layer contains at least a polymerizable compound having a molecular weight of 400 or less,
By providing the polymerizable composition for forming the light conversion layer on the surface of the adhesion improving layer precursor, the adhesion improving layer precursor is converted to the surface of the light conversion layer on the surface of the adhesion improving layer precursor and the light conversion. It converts into the adhesion improvement layer which has a mixed area | region with a layer component.

According to one embodiment of the present invention, it is possible to provide a light conversion member that can increase front luminance when incorporated in a liquid crystal display device and has excellent light resistance.
Furthermore, according to one embodiment of the present invention, a liquid crystal display device which can display a clear image with high front luminance and front contrast and little color unevenness can be provided.

1A and 1B are explanatory diagrams of an example of a backlight unit including a light conversion member according to one embodiment of the present invention. FIG. 2 illustrates an example of a liquid crystal display device according to one embodiment of the present invention. FIG. 3 shows the layer structure of the light conversion members of Examples 1 and 3-5. FIG. 4 shows the layer structure of the light conversion member of Example 2. FIG. 5 shows the layer structure of the light conversion member of Comparative Example 1. FIG. 6 shows the layer structure of the light conversion member of Comparative Example 2. FIG. 7 shows the layer structure of the light conversion members of Examples 6 to 9 and Comparative Example 3. FIG. 8 shows the layer structure of the light conversion member of Example 10 and Comparative Example 4. FIG. 9 is a schematic configuration diagram of an example of an apparatus for manufacturing a light conversion member. 10 is a partially enlarged view of the manufacturing apparatus shown in FIG.

[Optical Conversion Member and Manufacturing Method Thereof]
The light conversion member according to one embodiment of the present invention is a light conversion member having a light conversion layer including quantum dots that are excited by incident excitation light and emit fluorescence. The above-mentioned light conversion layer has an adjacent inorganic layer, and has means for bringing the light conversion layer and the inorganic layer into close contact with each other. As a specific one aspect, the above-described light conversion member has an adjacent inorganic layer in direct contact with the light conversion layer. Here, “directly contacting” means that two layers are adjacently disposed without interposing another layer such as an adhesive layer. And the said light conversion layer contains a quantum dot in an organic matrix, and further contains an adhesion improving agent. Moreover, as another aspect, the above-described light conversion member includes the light conversion layer, an adhesion improvement layer that is in direct contact with the light conversion layer, and an inorganic layer that is in direct contact with the adhesion improvement layer. The light conversion layer includes quantum dots in an organic matrix, forms a mixed region with the adhesion improving layer, the adhesion improving layer further includes an adhesion improving agent, and the adhesion improving layer further includes the light improving layer. It has a mixed region of the adhesion improving layer component and the light conversion layer component on the surface on the conversion layer side. The adhesion improving agent here has a function of mainly improving the adhesion between the inorganic layer and the light conversion layer, or between the inorganic layer and the adhesion improving layer.
As described above, since the inorganic layer has excellent barrier properties, providing an inorganic layer as an adjacent layer in direct contact with the light conversion layer containing the quantum dots in the organic matrix is effective in suppressing the photooxidation reaction of the quantum dots. is there. However, the light conversion layer, the adjacent inorganic layer in direct contact with the light conversion layer, and the inorganic layer laminated through the light conversion layer and the adhesion improving layer (hereinafter referred to as these inorganic layers, If the adhesiveness to the “inorganic layer closest to the light conversion layer” is insufficient, it is difficult to sufficiently prevent oxygen from being taken into the light conversion layer even if an inorganic layer is provided. . In addition, at the interface, since the adhesion is insufficient, a difference in refractive index occurs between the portion where the void is present and the portion where the void is not present, thereby reducing the light transmittance of the light conversion member. When such a conversion member is incorporated in a liquid crystal display device, the front luminance of the liquid crystal display device is lowered. If it is only to suppress the photo-oxidation reaction of quantum dots, it may be possible to strengthen the barrier property by stacking a number of layers having a barrier property, but the light transmittance of the light conversion member increases as the number of layers increases. Since it tends to decrease, it is not preferable from the viewpoint of achieving both high front luminance and light resistance when incorporated in a liquid crystal display device. In contrast, in the light conversion member according to one embodiment of the present invention, the light conversion layer includes an adhesion improving agent. By this adhesion improving agent, the adhesion between the light conversion layer and the adjacent inorganic layer becomes strong, so that it is possible to improve the light resistance of the light conversion layer without laminating many layers having a barrier property. . Further, in the light conversion member according to another aspect of the present invention, the light conversion layer includes an adhesion improving layer between the light conversion layer and the adjacent inorganic layer, and the adhesion improvement layer has a mixed region with the light conversion layer, And an adhesion improving agent is included. By this adhesion improving layer, the light conversion layer and the adhesion improving layer, and the adhesion improving layer and the inorganic layer are firmly adhered to each other, and the light resistance of the light converting layer is improved without laminating many layers having barrier properties. It becomes possible. Thus, according to one aspect of the present invention, there is provided a light conversion member including quantum dots, which can increase front luminance when incorporated in a liquid crystal display device and has excellent light resistance. be able to.
In addition, it is preferable that a light conversion member has high transparency.
Hereinafter, the light conversion member will be described in more detail.

The following description may be made based on representative embodiments of the present invention, but the present invention is not limited to such embodiments. In the present invention and this specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
Further, in the present invention and the present specification, the “half-value width” of a peak refers to the width of the peak at a peak height of ½. Further, light having an emission center wavelength in the wavelength band of 430 to 480 nm is called blue light, light having an emission center wavelength in the wavelength band of 500 to 600 nm is called green light, and the emission center wavelength is in the wavelength band of 600 to 680 nm. The light having a color is called red light.
The light conversion member is also referred to as a wavelength conversion member, and the light conversion layer is also referred to as a wavelength conversion layer.

  The light conversion member is preferably included as a constituent member of a backlight unit of a liquid crystal display device.

FIG. 1 is an explanatory diagram of an example of a backlight unit 31 including a light conversion member according to one embodiment of the present invention. In FIG. 1, the backlight unit 31 includes a light source 31A and a light guide plate 31B for use as a surface light source. In the example shown in FIG. 1A, the light conversion member is disposed on the path of light emitted from the light guide plate. On the other hand, in the example shown in FIG. 1B, the light conversion member is disposed between the light guide plate and the light source.
In the example shown in FIG. 1A, light emitted from the light guide plate 31B enters the light conversion member 31C. In the example shown in FIG. 1A, the light 32 emitted from the light source 31A arranged at the edge portion of the light guide plate 31B is blue light, and the liquid crystal is applied from the surface on the liquid crystal cell (not shown) side of the light guide plate 31B. It is emitted toward the cell. The light conversion member 31C disposed on the path of the light (blue light 32) emitted from the light guide plate 31B has the quantum dots (A) that are excited by the blue light 32 and emit the red light 34, and the blue light 32. It includes at least quantum dots (B) that are excited to emit green light 33. In this way, the backlight unit 31 emits the excited green light 33 and red light 34 and the blue light 32 transmitted through the light conversion member 31C. By emitting RGB bright line light in this way, white light can be realized.
The example shown in FIG. 1B is the same as the embodiment shown in FIG. 1A except that the arrangement of the light conversion member and the light guide plate is different. In the example shown in FIG. 1B, the excited green light 33 and red light 34, and the blue light 32 transmitted through the light conversion member 31C are emitted from the light conversion member 31C and incident on the light guide plate. Realized.

<Light conversion layer>
The light conversion member has at least a light conversion layer including quantum dots that are excited by incident excitation light and emit fluorescence. As other layers, the light conversion member according to one embodiment of the present invention includes an inorganic layer in direct contact with the light conversion layer. Details thereof will be described later.

(Quantum dot)
The light conversion layer includes at least one kind of quantum dot, and can also include two or more kinds of quantum dots having different emission characteristics. Known quantum dots include quantum dots (A) having an emission center wavelength in the wavelength band of 600 nm to 680 nm, quantum dots (B) having an emission center wavelength in the wavelength band of 500 nm to 600 nm, and 400 nm to 500 nm. There is a quantum dot (C) having a light emission center wavelength in the wavelength band, and the quantum dot (A) is excited by excitation light to emit red light, the quantum dot (B) emits green light, and the quantum dot (C). Emits blue light. For example, when blue light is incident as excitation light on a light conversion layer including quantum dots (A) and quantum dots (B), red light emitted from the quantum dots (A), quantum dots as shown in FIG. White light can be realized by the green light emitted by (B) and the blue light transmitted through the light conversion layer. Alternatively, red light or quantum dots (B) emitted from the quantum dots (A) by making ultraviolet light incident on the light conversion layer including the quantum dots (A), (B), and (C) as excitation light. White light can be realized by green light emitted by the blue light and blue light emitted by the quantum dots (C).

  The light conversion layer in the light conversion member according to one embodiment of the present invention includes quantum dots in an organic matrix. The organic matrix is usually a polymer obtained by polymerizing a polymerizable composition for forming a light conversion layer by light irradiation or the like. The shape of the light conversion layer is not particularly limited, and may be any shape such as a sheet shape or a bar shape. As for the quantum dots, for example, paragraphs 0060 to 0066 of JP2012-169271A can be referred to, but the quantum dots are not limited thereto. As the quantum dots, commercially available products can be used without any limitation. The emission wavelength of the quantum dots can usually be adjusted by the composition and size of the particles, and the composition and size.

  The light conversion layer in the light conversion member according to one embodiment of the present invention preferably emits fluorescence that retains at least part of the polarization of incident light from the viewpoints of luminance improvement and low power consumption. As a specific example of a light conversion layer capable of emitting fluorescence that retains at least a part of the polarization of incident light, quantum rod type quantum dots described in non-patent literature (THE PHYSICAL CHEMISTRYLETTERS 2013, 4, 502-507) May be used. Fluorescence that partially retains the polarization of incident light means that light emitted from the light conversion sheet is not 0% when excitation light having a degree of polarization of 99.9% is incident on the light conversion sheet. Preferably, the degree of polarization is 10 to 99.9%, and more preferably 80 to 99.9%. The upper limit is not particularly limited, but in actual use, it includes the effects of depolarization caused by variations in the production of quantum rods and variations in film formation. The degree may be 99% or less, or 90% or less.

  Quantum dots may be added to the polymerizable composition in the form of particles, or may be added in the form of a dispersion dispersed in a solvent. The addition in the state of a dispersion is preferable from the viewpoint of suppressing the aggregation of the quantum dot particles. The solvent used here is not particularly limited. A quantum dot can be added about 0.1-10 mass parts with respect to 100 mass parts of whole quantity of a polymeric composition, for example.

(Adhesion improver)
The light conversion layer is preferably produced by a coating method. Specifically, a light conversion layer is obtained by applying a polymerizable composition (curable composition) for forming a light conversion layer containing quantum dots on a substrate and then applying a curing treatment by light irradiation or the like. be able to. Here, a light conversion layer containing an adhesion improving agent can be formed by using a composition containing an adhesion improving agent together with quantum dots and a polymerizable compound as the polymerizable composition. Since the light conversion layer formed from the polymerizable composition containing the adhesion improving agent has strong adhesion to the adjacent layer due to the adhesion improving agent, it can exhibit excellent light resistance. This is mainly because the adhesion improver contained in the light conversion layer is caused by the formation of a covalent bond accompanying a hydrolysis reaction or a condensation reaction, or by the action of a non-covalent bond such as a hydrogen bond, or the surface of an adjacent layer or this layer. By forming a bond with the component. In addition, when the adhesion improving agent has a reactive functional group such as a radical polymerizable group, the monomer component constituting the light conversion layer and the formation of a crosslinked structure also improve the adhesion between the light conversion layer and the adjacent layer. Can contribute. As the adhesion improving agent, a silane coupling agent capable of forming a covalent bond with the inorganic layer is preferable. In the present invention, the adhesion improving agent contained in the light conversion layer is used in the sense of including the adhesion improving agent in the form after the reaction as described above.

  Specific examples of the adhesion improver include an organic metal coupling agent such as a silane coupling agent, a polymerizable compound having a phosphate group, and a molecule of at least one structure selected from a urethane bond, a urea bond, and an isocyanuric ring. Examples thereof include a polymerizable compound contained therein, a polymerizable compound having an isocyanate group, a polymerizable compound having a carboxyl group, and a polymerizable compound containing a hydroxyl group. Among these, the adhesion improver includes an organometallic coupling agent, a polymerizable compound having a phosphate group, and a polymerizable compound having at least one structure selected from a urethane bond, a urea bond, and an isocyanuric ring in the molecule. It is preferable that it is at least one of these.

-Silane coupling agent-
As the silane coupling agent, a known silane coupling agent can be used without any limitation. As a preferable silane coupling agent from the viewpoint of adhesion, a silane coupling agent represented by the following general formula (1) described in JP2013-43382A can be exemplified.

（一般式（１）中、Ｒ¹〜Ｒ⁶は、それぞれ独立に、置換もしくは無置換のアルキル基またはアリール基である。但し、Ｒ¹〜Ｒ⁶のうち少なくとも１つは、ラジカル重合性の炭素−炭素二重結合を含む置換基である。）

(In General Formula (1), R ^{1 to} R ⁶ are each independently a substituted or unsubstituted alkyl group or aryl group, provided that at least one of R ^{1 to} R ⁶ is a radical polymerizable group. This is a substituent containing a carbon-carbon double bond.)

R ^{1 to} R ⁶ are each independently a substituted or unsubstituted alkyl group or aryl group. R ^{1 to} R ⁶ are preferably an unsubstituted alkyl group or an unsubstituted aryl group, except in the case of a substituent containing a radical polymerizable carbon-carbon double bond. As an alkyl group, a C1-C6 alkyl group is preferable and a methyl group is more preferable. As the aryl group, a phenyl group is preferable. R ^{1 to} R ⁶ are particularly preferably a methyl group.

At least one of R ¹ to R ^6, the carbon radical polymerizable - having a substituent containing a carbon double bond, two of R ¹ to R ⁶ is a radical polymerizable carbon - carbon double bonds A substituent is preferred. Further, among R ^{1 to} R ³ , the number of those having a substituent containing a radical polymerizable carbon-carbon double bond is 1, and among R ^{4 to} R ⁶ , the radical polymerizable carbon-carbon It is particularly preferred that the number of those having a substituent containing a double bond is 1.
The substituents in which the silane coupling agent represented by the general formula (1) includes two or more radically polymerizable carbon-carbon double bonds may be the same or different. The same is preferable.

  The substituent containing a radically polymerizable carbon-carbon double bond is preferably represented by -XY. Here, X is a single bond, an alkylene group having 1 to 6 carbon atoms, or an arylene group, and preferably a single bond, a methylene group, an ethylene group, a propylene group, or a phenylene group. Y is a radically polymerizable carbon-carbon double bond group, and is preferably an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, a vinyl group, a propenyl group, a vinyloxy group, or a vinylsulfonyl group. ) An acryloyloxy group is more preferred.

R ^{1 to} R ⁶ may have a substituent other than a substituent containing a radically polymerizable carbon-carbon double bond. Examples of the substituent include alkyl groups (for example, methyl group, ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group). Etc.), aryl groups (eg phenyl group, naphthyl group etc.), halogen atoms (eg fluorine, chlorine, bromine, iodine), acyl groups (eg acetyl group, benzoyl group, formyl group, pivaloyl group etc.), acyloxy Groups (for example, acetoxy group, acryloyloxy group, methacryloyloxy group, etc.), alkoxycarbonyl groups (for example, methoxycarbonyl group, ethoxycarbonyl group, etc.), aryloxycarbonyl groups (for example, phenyloxycarbonyl group, etc.), sulfonyl groups ( For example, methanesulfonyl group, benzene Honiru group), and the like.

  Although the specific example of a compound represented by General formula (1) below is shown, this invention is not limited to these.

-Other organometallic coupling agents-
As other organometallic coupling agents, for example, various coupling agents such as a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, and a tin coupling agent can be used.

  Examples of titanium coupling agents include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) Titanate, tetra (2,2-diallyloxymethyl) bis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyldimethacrylisostearoyl Titanate, isopropyl isostearoyl diacryl titanate, isop Pirutori (dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri (N- aminoethyl-aminoethyl) titanate, dicumyl phenyloxy acetate titanate, diisostearoyl ethylene titanate.

  Examples of the zirconium coupling agent include tetra-n-propoxyzirconium, tetra-butoxyzirconium, zirconium tetraacetylacetonate, zirconium dibutoxybis (acetylacetonate), zirconium tributoxyethyl acetoacetate, zirconium butoxyacetylacetonate bis. (Ethyl acetoacetate) and the like.

  Examples of the aluminum coupling agent include aluminum isopropylate, monosec-butoxyaluminum diisopropylate, aluminum sec-butyrate, aluminum ethylate, ethylacetoacetate aluminum diisopropylate, aluminum tris (ethylacetoacetate), alkylacetate Acetate aluminum diisopropylate, aluminum monoacetylacetonate bis (ethyl acetoacetate), aluminum tris (acetylacetoacetate) and the like can be mentioned.

  From the viewpoint of further improving the adhesiveness with the inorganic layer closest to the light conversion layer, the silane coupling agent and the other organometallic coupling agent include 1 to 1 in the polymerizable composition for forming the light conversion layer. It is preferably contained in the range of 30% by mass, more preferably 3 to 30% by mass, and still more preferably 5 to 25% by mass.

  Further, as an adhesion improver, a polymerizable compound having a phosphate group, a polymerizable compound having at least one of a urethane group, a urea group, and an isocyanuric group, a polymerizable compound having an isocyanate group, a polymerizable monomer having a carboxyl group, A polymerizable compound having a hydroxyl group can be suitably used. These polymerizable compounds form non-covalent bonds such as hydrogen bonds and ionic bonds with the inorganic layer closest to the light conversion layer by the action of these functional groups, and the inorganic layer and the light conversion layer closest to the light conversion layer There is an effect of strengthening the close contact with.

-Polymerizable compound having a phosphate group-
Examples of the polymerizable compound having a phosphate group include monomers in which a polymerizable group is pendant as a residue of a phosphate ester.

  As the polymerizable compound having a phosphate ester group, polymerizable compounds represented by general formulas (1) to (4) of JP-A-2007-290369 can be preferably used.

  Only one type of polymerizable compound represented by the general formula (1) in JP-A-2007-290369 may be used, or two or more types may be used in combination. When used in combination, the monofunctional polymerizable compound represented by the general formula (2) of JP 2007-290369 A, and the bifunctional represented by the general formula (3) of JP 2007-290369 A You may use combining a polymeric compound and 2 or more types of the trifunctional polymeric compound represented by General formula (4) of Unexamined-Japanese-Patent No. 2007-290369.

Commercially available compounds such as the KAYAMER series manufactured by Nippon Kayaku Co., Ltd. and the Phosmer series manufactured by Unichemical Co., Ltd. may be used as they are as the polymerizable compounds having a phosphoric ester group. A synthesized compound may be used.
Although the specific example of the polymeric compound which has a phosphate ester group below is shown, the monomer which can be used by this invention is not limited to these.

  From the viewpoint of further improving the adhesion with the inorganic layer closest to the light conversion layer, the polymerizable compound having a phosphate group is 1 to 50% by mass in the polymerizable composition for forming the light conversion layer. It is preferably included in the range, more preferably 3 to 30% by mass, and further preferably 5 to 25% by mass.

-Polymerizable compound having in its molecule at least one structure selected from urethane bond, urea bond and isocyanuric ring-
(Meth) acrylate monomers containing urethane linkages include diisocyanates such as TDI, MDI, HDI, IPDI, HMDI, poly (propylene oxide) diol, poly (tetramethylene oxide) diol, ethoxylated bisphenol A, ethoxylated bisphenol Reaction of polyols such as S spiro glycol, caprolactone-modified diol, carbonate diol, and hydroxy acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidol di (meth) acrylate, pentaerythritol triacrylate Monomers and oligomers obtained by the method described above, and JP-A-2002-265650, JP-A-2002-355936, JP-A-2002-06723. It can be mentioned polyfunctional urethane monomers described in JP-like. Specifically, an adduct of TDI and hydroxyethyl acrylate, an adduct of IPDI and hydroxyethyl acrylate, an adduct of HDI and pentaerythritol triacrylate (PETA), and an adduct of TDI and PETA remained. Examples include compounds obtained by reacting isocyanate and dodecyloxyhydroxypropyl acrylate, adducts of 6,6 nylon and TDI, adducts of pentaerythritol, TDI and hydroxyethyl acrylate, but are not limited thereto. Absent.

  As a commercially available product that can be suitably used as a (meth) acrylate monomer containing a urethane bond, Kyoeisha Chemical Co., Ltd. AH-600, AT-600, UA-306H, UA-306T, UA-306I, UA-510H, Examples thereof include UF-8001G, DAUA-167, UA-160TM manufactured by Shin-Nakamura Chemical Co., Ltd., UV-4108F manufactured by Osaka Organic Chemical Industry Co., Ltd., and UV-4117F. These can be used alone or in combination of two or more.

  The polymerizable compound containing in the molecule at least one of a structure selected from a urethane bond, a urea bond, and an isocyanuric ring is a light conversion from the viewpoint of further improving the adhesion to the inorganic layer closest to the light conversion layer. It is preferable to contain in the range of 1-50 mass% in the polymeric composition for layer formation, More preferably, it is 3-30 mass%, More preferably, it is 5-25 mass%.

-Polymerizable compound containing isocyanate group-
A commercially available compound can be used as the polymerizable compound containing an isocyanate group. Moreover, the compound containing the blocked isocyanate group which covered the isocyanate group with the protective group is also handled as a polymerizable compound containing the isocyanate group in the present invention. Specific compounds include 2-isocyanatoethyl (meth) acrylate, (meth) acrylic acid-2- (0- [1′-methylpropylideneamino] carboxyamino) ethyl, 2-[(3,5-dimethyl). Examples include pyrazolyl) carbonylamino] ethyl (meth) acrylate, 1,1- (bisacryloyloxymethyl) ethyl isocyanate, 2-isocyanatoethyloxyethyl (meth) acrylate, and the like. These compounds can be obtained as Showa Denko Co., Ltd., trade names Karenz MOI, Karenz AOI, Karenz BEI, Karenz MOI-BP, Karenz MOI-BM, Karenz MOI-EG.

  From the viewpoint of further improving the adhesion with the inorganic layer closest to the light conversion layer, the polymerizable compound containing an isocyanate group is 0.1 to 30% by mass in the polymerizable composition for forming the light conversion layer. It is preferable that it is contained in the range, More preferably, it is 1-30 mass%, More preferably, it is 2-20 mass%.

-Polymerizable compound having a carboxyl group-
As the polymerizable compound having a carboxyl group, a compound obtained by the reaction of a polybasic acid or an anhydride thereof, a compound containing a hydroxyl group and a polymerizable group can be used, and is partially esterified in the reaction. As a result, a polymerizable compound containing a carboxyl group is obtained. Examples of the polybasic acid (anhydride) include (anhydrous) phthalic acid, terephthalic acid, isophthalic acid, (anhydrous) tetrahydrophthalic acid, (anhydrous) methyltetrahydrophthalic acid, (anhydrous) hexahydrophthalic acid, (anhydrous) Maleic acid, (anhydrous) succinic acid, itaconic acid, fumaric acid, (anhydrous) pyromellitic acid, (anhydrous) trimellitic acid, adipic acid, sebacic acid, azelaic acid, etc. You may combine. As the polymerizable compound containing a hydroxyl group, the following can be used. These may be used alone or in combination of two or more.

-Polymerizable compound containing a hydroxyl group-
As a polymerizable compound containing a hydroxyl group, for example, 2-hydroxyethyl acrylate, polyalkylene glycol mono (meth) acrylate having a terminal hydroxyl group, and an epoxy monomer known as an epoxy acrylate are condensed with (meth) acrylic acid. Thus, modified (meth) acrylates having a hydroxyl group in the skeleton can be used.

  From the viewpoint of further improving the adhesion with the inorganic layer closest to the light conversion layer, the polymerizable compound containing a hydroxyl group is in the range of 10 to 90% by mass in the polymerizable composition for forming the light conversion layer. It is preferable that it is contained, More preferably, it is 20-80 mass%, More preferably, it is 30-50 mass%.

(Polymerizable compound)
The polymerizable compound used for preparing the polymerizable composition is not particularly limited. Examples of the polymerizable compound include a polymerizable compound having a (meth) acrylate group and a compound having an epoxy group. A polymerizable compound that can also be used as an adhesion improver may be used as the polymerizable compound. From the viewpoints of transparency and adhesion of the cured film after curing, (meth) acrylate compounds such as monofunctional or polyfunctional (meth) acrylate monomers, polymers, prepolymers, etc., and monofunctional or polyfunctional Epoxy compounds such as epoxy monomers, polymers thereof, and prepolymers are preferred. In addition, in this invention and this specification, description with "(meth) acrylate" shall be used by the meaning of at least one of an acrylate and a methacrylate, or either. The same applies to “(meth) acryloyl” and the like. Moreover, the polymeric compound which has epoxy groups, such as a monofunctional or polyfunctional epoxy monomer, its polymer, a prepolymer, etc., and the combination of the polymeric compound which has these epoxy groups, and polyvalent amine compounds are also preferable. In the present invention and the present specification, the term “epoxy” refers to all cyclic ethers capable of ring-opening polymerization such as oxetane, in addition to compounds having an oxirane structure known as polymerizable compounds having a narrowly defined epoxy group. Shall be used to mean

-Polymerizable compound having (meth) acrylate group-
Monofunctional (meth) acrylate monomers include acrylic acid and methacrylic acid, derivatives thereof, and more specifically, monomers having one polymerizable unsaturated bond ((meth) acryloyl group) of (meth) acrylic acid in the molecule Can be mentioned. Specific examples thereof include the following compounds, but the present invention is not limited thereto.
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 ( Alkyl (meth) acrylates having an alkyl group such as meth) acrylate having 1 to 30 carbon atoms; aralkyl (meth) acrylates having an aralkyl group such as benzyl (meth) acrylate having 7 to 20 carbon atoms; butoxyethyl (meta) ) An alkoxyalkyl (meth) acrylate having 2 to 30 carbon atoms of an alkoxyalkyl group such as acrylate; the total carbon number of a (monoalkyl or dialkyl) aminoalkyl group such as N, N-dimethylaminoethyl (meth) acrylate 1-20 Aminoalkyl (meth) acrylates; (meth) acrylates of diethylene glycol ethyl ether, (meth) acrylates of triethylene glycol butyl ether, (meth) acrylates of tetraethylene glycol monomethyl ether, (meth) acrylates of hexaethylene glycol monomethyl ether, octa Monomethyl ether (meth) acrylate of ethylene glycol, monomethyl ether (meth) acrylate of nonaethylene glycol, monomethyl ether (meth) acrylate of dipropylene glycol, monomethyl ether (meth) acrylate of heptapropylene glycol, monoethyl ether of tetraethylene glycol Alkylene chain such as (meth) acrylate has 1 to 10 carbon atoms and terminal alkyl (Meth) acrylate of polyalkylene glycol alkyl ether having 1 to 10 carbon atoms; alkylene chain such as (meth) acrylate of hexaethylene glycol phenyl ether having 1 to 30 carbon atoms and terminal aryl ether having 6 carbon atoms (Meth) acrylate of -20 polyalkylene glycol aryl ethers; alicyclic structures such as cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate, and methylene oxide-added cyclodecatriene (meth) acrylate (Meth) acrylate having 4 to 30 carbon atoms in total; fluorinated alkyl (meth) acrylate having 4 to 30 carbon atoms in total such as heptadecafluorodecyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 3 -Hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) acrylate, octapropylene glycol mono ( (Meth) acrylate, (meth) acrylate having a hydroxyl group such as glycerol mono- or di (meth) acrylate; (meth) acrylate having a glycidyl group such as glycidyl (meth) acrylate; tetraethylene glycol mono (meth) acrylate, hexaethylene Polyethylene glycol mono (meth) having 1 to 30 carbon atoms in the alkylene chain such as glycol mono (meth) acrylate and octapropylene glycol mono (meth) acrylate Acrylate; (meth) acrylamide, N, N- dimethyl (meth) acrylamide, N- isopropyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide, acryloyl morpholine (meth) acrylamide and the like.

  As the monofunctional (meth) acrylate monomer, it is preferable to use an alkyl (meth) acrylate having 4 to 30 carbon atoms and a long chain alkyl group having 4 to 30 carbon atoms, and an alkyl (meth) having 12 to 22 carbon atoms. It is more preferable to use acrylate from the viewpoint of improving the dispersibility of the quantum dots. As the dispersibility of the quantum dots improves, the amount of light that goes straight from the light conversion layer to the exit surface increases, which is effective in improving front luminance and front contrast. Specifically, monofunctional (meth) acrylate monomers include butyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, oleyl (meth) acrylate, stearyl (meth) acrylate, and behenyl (meth) acrylate. Butyl (meth) acrylamide, octyl (meth) acrylamide, lauryl (meth) acrylamide, oleyl (meth) acrylamide, stearyl (meth) acrylamide, behenyl (meth) acrylamide and the like are preferable. Of these, lauryl (meth) acrylate, oleyl (meth) acrylate, and stearyl (meth) acrylate are particularly preferable.

Polyfunctional (meth) acrylate monomer having two or more (meth) acryloyl groups in the molecule together with a monomer having one polymerizable unsaturated bond ((meth) acryloyl group) in one molecule. Can also be used together. Specific examples include the following compounds, but the present invention is not limited thereto.
Alkylene glycol di having 1 to 20 carbon atoms in the alkylene chain, such as 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate (Meth) acrylate; polyalkylene glycol di (meth) acrylate having 1 to 20 carbon atoms in the alkylene chain such as polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate; trimethylolpropane tri (meth) acrylate, Tri (meth) acrylate having a total carbon number of 10-60, such as ethylene oxide-added trimethylolpropane tri (meth) acrylate; ethylene oxide-added pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) Acrylate, the total number of carbon atoms such as pentaerythritol tetra (meth) acrylate is 10 to 100 of the tetra (meth) acrylate; and the like dipentaerythritol hexa (meth) acrylate.

  The amount of the polyfunctional (meth) acrylate monomer used is preferably 5 parts by mass or more from the viewpoint of coating strength with respect to 100 parts by mass of the total amount of polymerizable compounds contained in the polymerizable composition. From the viewpoint of suppressing the gelation of the product, it is preferably 95 parts by mass or less.

-Polymerizable compound having an epoxy group-
As the polymerizable compound having an epoxy group used in the present invention, a commercially available epoxy monomer may be used, or a commercially available epoxy composition in which several components are mixed and prepared in advance according to the use conditions. Good. Commercially available epoxy compositions are commercially available as adhesives or sealants. For example, it can be obtained from Three Bond, EMI, Tesque, Henkel, and the like. Specifically, OPTOCAST (trade name) 3505, 3506, and 3553 manufactured by EMI, A-1771 (trade name) manufactured by Tesque, and Loctite E-30CL manufactured by Henkel are exemplified.

(Polymerization initiator)
The polymerizable composition may contain a known radical polymerization initiator or cationic polymerization initiator as a polymerization initiator.
The polymerizable composition containing a polymerizable compound such as the (meth) acrylate monomer can contain a known radical polymerization initiator as a polymerization initiator. The polymerizable composition containing a polymerizable compound such as a polymerizable compound having an epoxy group can contain a known cationic polymerization initiator as a polymerization initiator. As for the polymerization initiator, reference can be made, for example, to paragraph 0037 of JP2013-043382A and paragraphs 0040 to 0042 of JP2011-159924A. The polymerization initiator is preferably 0.01 mol% or more, more preferably 0.5 to 2 mol%, based on the total amount of the polymerizable compounds contained in the polymerizable composition.

(Rubber particles)
The polymerizable composition may contain rubber particles. By including the rubber particles, the light conversion layer can be prevented from becoming brittle. Examples of the rubber particles include a rubbery polymer having acrylate as a main constituent monomer, a rubbery polymer having butadiene as a main constituent monomer, and an ethylene-vinyl acetate copolymer. A rubber particle may be used individually by 1 type, and 2 or more types may be mixed and used for it. Regarding the rubber particles, reference can be made to the descriptions in 0061 to 0069 of JP-A-2014-35393.

(solvent)
The polymerizable composition may contain a solvent as necessary. In this case, the type and amount of the solvent used are not particularly limited. For example, one or a mixture of two or more organic solvents can be used as the solvent.

(Film thickness)
The total thickness of the light conversion layer is preferably in the range of 1 to 500 μm, more preferably in the range of 10 to 250 μm, and still more preferably in the range of 30 to 150 μm. A thickness of 1 μm or more is preferable because a high wavelength conversion effect (light wavelength conversion effect) can be obtained. Further, it is preferable that the thickness is 500 μm or less because the backlight unit can be thinned when incorporated in the backlight unit.

(Method for forming light conversion layer)
One aspect of the method for producing a light conversion member of the present invention is a surface of the first barrier film including at least an inorganic layer, or a surface of an adhesion improving layer that may be optionally provided on the surface of the inorganic layer. A step of providing a polymerizable composition for forming a light conversion layer containing quantum dots and a polymerizable compound;
A step of forming the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film.

  As an outline of the method for producing a light conversion member of the present invention, the above-described polymerizable composition for forming a light conversion layer (also referred to as a polymerizable composition including quantum dots or a quantum dot-containing polymerizable composition) is used. It can be coated on a support such as a first barrier film containing at least an inorganic layer, dried to remove the solvent, and then polymerized and cured by light irradiation to obtain a light conversion layer containing quantum dots. it can.

Formation of a light conversion layer containing quantum dots and a polymerizable compound on the surface of the inorganic layer of the first barrier film containing at least the inorganic layer, or on the surface of the adhesion improving layer optionally provided on the surface of the inorganic layer The step of providing the polymerizable composition for the production of the quantum dots on the surface of the inorganic layer of the first barrier film including at least the inorganic layer when manufacturing a light conversion member having an adjacent inorganic layer in direct contact with the light conversion layer And a polymerizable composition for forming a light conversion layer containing a polymerizable compound, and the polymerizable composition for forming a light conversion layer preferably further contains an adhesion improving agent. On the other hand, the light conversion containing a quantum dot and a polymerizable compound on the surface of the inorganic layer of the first barrier film including at least the inorganic layer, or the surface of the adhesion improving layer optionally provided on the surface of the inorganic layer The step of providing a polymerizable composition for forming a layer has an adhesion improving layer in direct contact with the light conversion layer, and has an inorganic layer in direct contact with the adhesion improving layer, and the adhesion improving layer is an adhesion improving agent. In addition, in the case of producing a light conversion member in which the adhesion improving layer has a mixed region of the adhesion improving layer component and the light conversion layer component on the surface of the light conversion layer side, at least an inorganic layer is included. This is a step of providing a polymerizable composition for forming a light conversion layer containing quantum dots and a polymerizable compound on the surface of the adhesion improving layer provided on the surface of the inorganic layer of one barrier film.
Formation of a light conversion layer containing quantum dots and a polymerizable compound on the surface of the inorganic layer of the first barrier film containing at least the inorganic layer, or on the surface of the adhesion improving layer optionally provided on the surface of the inorganic layer The step of providing the polymerizable composition for use is preferably a step of applying a polymerizable composition for forming a light conversion layer containing quantum dots and a polymerizable compound. Application methods include curtain coating, dip coating, spin coating, print coating, spray coating, slot coating, roll coating, slide coating, blade coating, gravure coating, wire bar method, etc. A well-known coating method is mentioned. In particular, when the inorganic layer and the light conversion layer are provided adjacent to each other, a coating method in which the support and the coater are non-contact is preferable. For example, a curtain coating method, a spray coating method, a slot coating method and the like are preferable.
In addition, there is no restriction | limiting in particular as a method of providing an adhesion improvement layer in the surface of the said inorganic layer of the 1st barrier film containing an inorganic layer at least, The polymerizable composition for light conversion layer formation is provided in the surface of the said inorganic layer. The adhesion improving layer can be provided by a method similar to the method.
The first barrier film is preferably a barrier film including an inorganic layer closest to the light conversion layer. The first barrier film preferably further includes one or more layers selected from the group consisting of an inorganic layer and an organic layer on the surface of the inorganic layer closest to the light conversion layer opposite to the light conversion layer side.
In one aspect of the production method of the present invention, the polymerizable composition for forming the light conversion layer contains at least a polymerizable compound having a molecular weight of 400 or less, and the polymerization for forming the light conversion layer is formed on the surface of the adhesion improving layer precursor. Preferably, the adhesion improving layer precursor is converted into an adhesion improving layer having a mixed region of the adhesion improving layer precursor component and the light converting layer component on the surface of the light conversion layer by the step of providing an adhesive composition. . By this method, it has an adhesion improving layer in direct contact with the light conversion layer, has an inorganic layer in direct contact with the adhesion improving layer, the adhesion improving layer contains an adhesion improving agent, and further, the adhesion improving layer However, the light conversion member which has the mixed area | region of the said contact improvement layer component and the said light conversion layer component on the surface by the side of the said light conversion layer can be manufactured easily. The molecular weight of the polymerizable compound used in the polymerizable composition for forming the light conversion layer is preferably 150 to 400, more preferably 180 to 380, and most preferably 200 to 360. When the molecular weight of the polymerizable compound used in the polymerizable composition for forming the light conversion layer is not more than the above upper limit, it becomes easy to form a mixed region, and the polymerization used in the polymerizable composition for forming the light conversion layer If the molecular weight of the polymerizable compound is equal to or higher than the lower limit, problems in the process due to volatilization of the polymerizable compound can be easily avoided.

  The method for producing a light conversion member of the present invention preferably includes a step of heating the polymerizable composition for forming the light conversion layer before the step of forming the light conversion layer. Specifically, the polymerizable composition for forming the light conversion layer at a preferable aspect or a preferable temperature in the step of heating the polymerizable composition in the description of one aspect of the manufacturing process of the light conversion member with reference to the drawings described below. It is preferable to heat.

In the step of forming the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film. Polymerization (also referred to as curing) conditions can be appropriately set according to the type of polymerizable compound used and the composition of the polymerizable composition.
Moreover, when a quantum dot containing polymeric composition is a composition containing a solvent, you may give a drying process for solvent removal before hardening.

The quantum dot-containing polymerizable composition may be cured in a state where the quantum dot-containing polymerizable composition is sandwiched between two substrates. In the present invention, before the step of forming the light conversion layer, the formation of the light conversion layer provided with the second barrier film on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film. The step of forming the light conversion layer includes the step of placing the polymerizable composition for contact with the surface opposite to the side on which the first barrier film is provided. It is also preferable to form the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer in a state where the light conversion layer and the second barrier film are laminated in this order. .
The second barrier film is provided with the first barrier film of the polymerizable composition for forming the light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film. The step of disposing the surface to be in contact with the surface opposite to the side on which the light-conducting side is in contact with the surface of the first barrier film in the case of producing a light-conversion member having an adjacent inorganic layer that is in direct contact with the light-conversion layer. It is the process of arrange | positioning so that the surface on the opposite side to the side in which the said 1st barrier film is provided of the polymeric composition for the said light conversion layer formation provided in the surface of the said inorganic layer may be contact | connected. On the other hand, the first barrier film of the polymerizable composition for forming a light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film is a second barrier film. The step of arranging to be in contact with the surface opposite to the provided side has an adhesion improving layer in direct contact with the light conversion layer, an inorganic layer in direct contact with the adhesion improving layer, and the adhesion When the improvement layer contains an adhesion improver, and the adhesion improvement layer further produces a light conversion member having a mixed region of the adhesion improvement layer component and the light conversion layer component on the surface of the light conversion layer, The second barrier film is opposite to the side on which the first barrier film of the polymerizable composition for forming a light conversion layer provided on the surface of the adhesion improving layer of the first barrier film is provided. So that it touches the side surface. It is a step for.
The second barrier film can be formed on the surface of the above light conversion layer opposite to the inorganic layer side closest to the light conversion layer, and has at least one layer selected from the group consisting of an inorganic layer and an organic layer. It is preferable that it is a barrier film which has. As the inorganic layer and the organic layer used in the second barrier film, the inorganic layer or the organic layer described in the other inorganic layer or the organic layer can be used.
In the step of forming the light conversion layer, the polymerizable composition for forming the light conversion layer is polymerized in a state where the first barrier film, the light conversion layer, and the second barrier film are laminated in this order. With respect to an aspect that is a process of forming the light conversion layer, an aspect of a process for producing a light conversion member including a process of forming the light conversion layer (curing treatment) will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments.

  FIG. 9 is a schematic configuration diagram of an example of a light conversion member manufacturing apparatus, and FIG. 10 is a partial enlarged view of the manufacturing apparatus shown in FIG. The manufacturing process of the light conversion member using the manufacturing apparatus shown in FIG. 9 and FIG. 10 is a quantum dot containing polymeric composition on the surface of the 1st base material (henceforth a "1st film") conveyed continuously. And a step of forming a coating film and laminating (overlapping) a second substrate (hereinafter also referred to as “second film”) continuously conveyed on the coating film, Backing up either the first film or the second film with the step of sandwiching the coating film between the film and the second film and the state where the coating film is sandwiched between the first film and the second film A process of forming a light conversion layer (cured layer) by wrapping around a roller and irradiating with light while continuously transporting to polymerize and cure the coating film. By using a barrier film having a barrier property against oxygen or moisture as either the first film or the second film, a light conversion member having one surface protected by the barrier film can be obtained. Moreover, the light conversion member by which both surfaces of the light conversion layer were protected by the barrier film can be obtained by using a barrier film as the first film and the second film, respectively.

  More specifically, first, the first film 10 is continuously conveyed to the coating unit 20 from a delivery machine (not shown). For example, the first film 10 is sent out from the sending machine at a conveying speed of 1 to 50 m / min. However, it is not limited to this conveyance speed. When delivered, for example, a tension of 20 to 150 N / m, preferably 30 to 100 N / m, is applied to the first film 10.

  In the coating unit 20, a quantum dot-containing polymerizable composition (hereinafter also referred to as “coating liquid”) is applied to the surface of the first film 10 that is continuously conveyed, and a coating film 22 (see FIG. 10) is formed. Is done. In the coating unit 20, for example, a die coater 24 and a backup roller 26 disposed to face the die coater 24 are installed. The surface of the first film 10 opposite to the surface on which the coating film 22 is formed is wound around the backup roller 26, and the coating liquid is applied from the discharge port of the die coater 24 onto the surface of the first film 10 that is continuously conveyed. As a result, the coating film 22 is formed. Here, the coating film 22 refers to a quantum dot-containing polymerizable composition before being applied applied to the first film 10.

  In the present embodiment, the die coater 24 to which the extrusion coating method is applied is shown as the coating apparatus, but the present invention is not limited to this. For example, a coating apparatus to which various methods such as a curtain coating method, an extrusion coating method, a rod coating method, or a roll coating method are applied can be used.

  The first film 10 that has passed through the coating unit 20 and has the coating film 22 formed thereon is continuously conveyed to the laminating unit 30. In the laminating unit 30, the second film 50 that is continuously conveyed is laminated on the coating film 22, and the coating film 22 is sandwiched between the first film 10 and the second film 50.

  The laminating unit 30 is provided with a laminating roller 32 and a heating chamber 34 surrounding the laminating roller 32. The heating chamber 34 is provided with an opening 36 for allowing the first film 10 to pass therethrough and an opening 38 for allowing the second film 50 to pass therethrough.

  A backup roller 62 is disposed at a position facing the laminating roller 32. The first film 10 on which the coating film 22 is formed is wound around the backup roller 62 on the surface opposite to the surface on which the coating film 22 is formed, and is continuously conveyed to the laminating position P. The laminating position P means a position where the contact between the second film 50 and the coating film 22 starts. The first film 10 is preferably wound around the backup roller 62 before reaching the laminating position P. This is because even if wrinkles occur in the first film 10, the wrinkles are corrected by the backup roller 62 before reaching the laminate position P and can be removed. Therefore, the position (contact position) where the first film 10 is wound around the backup roller 62 and the distance L1 to the laminate position P are preferably long, for example, 30 mm or more is preferable, and the upper limit is usually It is determined by the diameter of the backup roller 62 and the pass line.

  In the present embodiment, the second film 50 is laminated by the backup roller 62 and the laminating roller 32 used in the curing unit 60. That is, the backup roller 62 used in the curing unit 60 is also used as a roller used in the laminating unit 30. However, the present invention is not limited to the above form, and a laminating roller may be installed in the laminating unit 30 in addition to the backup roller 62 so that the backup roller 62 is not used.

  By using the backup roller 62 used in the curing unit 60 in the laminating unit 30, the number of rollers can be reduced. The backup roller 62 can also be used as a heat roller for the first film 10.

  The second film 50 delivered from a delivery machine (not shown) is wound around the laminating roller 32 and continuously conveyed between the laminating roller 32 and the backup roller 62. The second film 50 is laminated on the coating film 22 formed on the first film 10 at the laminating position P. Accordingly, the coating film 22 is sandwiched between the first film 10 and the second film 50. Lamination refers to laminating the second film 50 on the coating film 22.

  The distance L2 between the laminating roller 32 and the backup roller 62 is a value of the total thickness of the first film 10, the light conversion layer (cured layer) 28 obtained by polymerizing and curing the coating film 22, and the second film 50. The above is preferable. Moreover, it is preferable that L2 is below the length which added 5 mm to the total thickness of the 1st film 10, the coating film 22, and the 2nd film 50. FIG. By setting the distance L2 to be equal to or shorter than the total thickness plus 5 mm, it is possible to prevent bubbles from entering between the second film 50 and the coating film 22. Here, the distance L <b> 2 between the laminating roller 32 and the backup roller 62 refers to the shortest distance between the outer peripheral surface of the laminating roller 32 and the outer peripheral surface of the backup roller 62.

  The rotational accuracy of the laminating roller 32 and the backup roller 62 is 0.05 mm or less, preferably 0.01 mm or less in radial runout. The smaller the radial runout, the smaller the thickness distribution of the coating film 22.

  Further, in order to suppress thermal deformation after the coating film 22 is sandwiched between the first film 10 and the second film 50, the difference between the temperature of the backup roller 62 of the curing unit 60 and the temperature of the first film 10. The difference between the temperature of the backup roller 62 and the temperature of the second film 50 is preferably 30 ° C. or less, more preferably 15 ° C. or less, and most preferably the same.

  In order to reduce the difference from the temperature of the backup roller 62, when the heating chamber 34 is provided, it is preferable to heat the first film 10 and the second film 50 in the heating chamber 34. For example, hot air is supplied to the heating chamber 34 by a hot air generator (not shown), and the first film 10 and the second film 50 can be heated.

  The first film 10 may be heated by the backup roller 62 by being wound around the temperature-adjusted backup roller 62.

On the other hand, the second film 50 can be heated by the laminating roller 32 by using the laminating roller 32 as a heat roller.
However, the heating chamber 34 and the heat roller are not essential and can be provided as necessary.

  Next, in a state where the coating film 22 is sandwiched between the first film 10 and the second film 50, the film is continuously conveyed to the curing unit 60. In the embodiment shown in the drawing, curing in the curing unit 60 is performed by light irradiation. However, when the polymerizable compound contained in the quantum dot-containing polymerizable composition is polymerized by heating, such as spraying warm air. Curing can be performed by heating.

A light irradiation device 64 is provided at a position facing the backup roller 62 and the backup roller 62. The first film 10 and the second film 50 sandwiching the coating film 22 are continuously conveyed between the backup roller 62 and the light irradiation device 64. What is necessary is just to determine the light irradiated by a light irradiation apparatus according to the kind of photopolymerizable compound contained in a quantum dot containing polymeric composition, and an ultraviolet-ray is mentioned as an example. Here, the ultraviolet light refers to light having a wavelength of 280 to 400 nm. As a light source that generates ultraviolet rays, for example, 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, or the like can be used. What is necessary is just to set the light irradiation amount to the range which can advance polymerization hardening of a coating film, for example, can irradiate the coating film 22 with the ultraviolet-ray of the irradiation amount of 100-10000mJ / cm < ² > as an example.

  In the curing unit 60, the first film 10 is wound around the backup roller 62 in a state where the coating film 22 is sandwiched between the first film 10 and the second film 50, and is continuously conveyed from the light irradiation device 64. The light conversion layer (cured layer) 28 can be formed by performing light irradiation to cure the coating film 22.

  In the present embodiment, the first film 10 side is wound around the backup roller 62 and continuously conveyed, but the second film 50 may be wound around the backup roller 62 and continuously conveyed.

  Wrapping around the backup roller 62 means a state in which either the first film 10 or the second film 50 is in contact with the surface of the backup roller 62 at a certain wrap angle. Accordingly, the first film 10 and the second film 50 move in synchronization with the rotation of the backup roller 62 while being continuously conveyed. Winding around the backup roller 62 may be at least during the irradiation of ultraviolet rays.

  The backup roller 62 includes a cylindrical body and rotation shafts disposed at both ends of the body. The main body of the backup roller 62 has a diameter of φ200 to 1000 mm, for example. There is no restriction on the diameter φ of the backup roller 62. In consideration of curl deformation of the light conversion member, equipment cost, and rotation accuracy, the diameter is preferably 300 to 500 mm. The temperature of the backup roller 62 can be adjusted by attaching a temperature controller to the main body of the backup roller 62.

  The temperature of the backup roller 62 takes into consideration the heat generation during light irradiation, the curing efficiency of the coating film 22, and the occurrence of wrinkle deformation on the backup roller 62 of the first film 10 and the second film 50. Can be determined. For example, the backup roller 62 is preferably set to a temperature range of 10 to 95 ° C, and more preferably 15 to 85 ° C. Here, the temperature related to the roller refers to the surface temperature of the roller.

  A distance L3 between the laminate position P and the light irradiation device 64 can be set to, for example, 30 mm or more.

  The coating film 22 becomes a light conversion layer (cured layer) 28 by light irradiation, and a light conversion member 70 is formed. The light conversion member 70 is peeled off from the backup roller 62 by the peeling roller 80. The light conversion member 70 is continuously conveyed to a winder (not shown), and then the light conversion member 70 is wound into a roll by the winder. In the case where at least one is an easily peelable film and the easily peelable film is peeled and removed, the easily peelable film may be removed by using a peeling roll or the like at this winding stage, or once easily peelable After being wound together with the film, an additional step may be added before applying to the inorganic layer deposition machine, or at the unwinding part in the inorganic layer deposition machine, the easily peelable film is removed simultaneously with unwinding. May be. From the viewpoint of preventing the adhesion of foreign matters to the surface and the influence of the deterioration of the quantum dots, it is preferable to remove the easily peelable film in the inorganic layer deposition machine.

  In addition, the process for forming the light conversion layer using the support has been described so far. For example, if the method described in JP-A-2-214622 is used, the light conversion can be performed without using the support. A layer can be formed. In this case, since a transparent support is not used, it is extremely advantageous in terms of material cost and thickness of the light conversion member. Moreover, although the example which manufactures using a metal roll is described in this gazette, it can replace with a metal roll and can also form into a film using a metal band apparatus of an infinite end, for example.

  As mentioned above, although the one aspect | mode of the manufacturing process of the light conversion member was demonstrated, this invention is not limited to the said aspect. In addition, an easily peelable protective film (so-called laminate film) can be provided on the surface for transportation and storage.

<Inorganic layer closest to the light conversion layer>
The light conversion member according to one embodiment of the present invention is laminated through an inorganic layer (adjacent inorganic layer) that is in direct contact with the light conversion layer or an adhesion improving layer as the inorganic layer closest to the light conversion layer. Having an inorganic layer formed. The inorganic layer directly in contact with the light conversion layer or the inorganic layer laminated via the light conversion layer and the adhesion improving layer will be collectively described as “an inorganic layer closest to the light conversion layer”. By including an adhesion improving agent in this light conversion layer or adhesion improvement layer, the adhesion between the light conversion layer and the inorganic layer closest to the light conversion layer becomes strong, and thus incorporated in a liquid crystal display device. In some cases, it is possible to obtain a light conversion member having high front luminance and excellent light resistance. The adhesion improving layer will be described later.

From the viewpoint of realizing further excellent barrier properties, it is preferable to form an inorganic layer closest to the light conversion layer by depositing an inorganic material on a suitable base material by vapor deposition.
Here, the vapor deposition in the present invention refers to various film forming methods capable of evaporating or scattering the film forming material and depositing it on the surface to be vapor-deposited. Phase growth methods (PVD) and various chemical vapor deposition methods (CVD) are included.
In the present invention, the “inorganic layer” is a layer mainly composed of an inorganic material, preferably a layer formed only from an inorganic material. On the other hand, the organic layer is a layer mainly composed of an organic material, and preferably refers to a layer in which the organic material occupies 50% by mass or more, more preferably 80% by mass or more, and particularly 90% by mass or more. To do.

The formation order of the inorganic layer closest to the light conversion layer and the light conversion layer may be such that after forming the inorganic layer that becomes the inorganic layer closest to the light conversion layer, the light conversion layer may be formed directly on the inorganic layer, After forming the light conversion layer, an inorganic layer closest to the light conversion layer may be formed directly on the light conversion layer, preferably by vapor deposition. In order to further enhance the adhesion between the light conversion layer and the inorganic layer closest to the light conversion layer, after applying a polymerizable composition for forming a light conversion layer on the inorganic layer, the polymerizable composition is applied to the polymerizable composition. It is preferable to form the light conversion layer by performing polymerization treatment such as light irradiation.
That is, one embodiment of the present invention is
Formation of a light conversion layer containing quantum dots and a polymerizable compound on the surface of the inorganic layer of the first barrier film containing at least the inorganic layer, or on the surface of the adhesion improving layer optionally provided on the surface of the inorganic layer Providing a polymerizable composition for,
Including the step of forming the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer provided on the surface of the inorganic layer or the surface of the adhesion improving layer of the first barrier film, The present invention relates to a method for manufacturing the light conversion member.
One embodiment of the present invention is to form an inorganic layer to be an adjacent inorganic layer, and
After applying a polymerizable composition containing a quantum dot, a silane coupling agent, and a polymerizable compound directly on at least one surface of the formed inorganic layer, the above light conversion is performed by subjecting this polymerizable composition to a polymerization treatment. Forming a layer,
It is preferable to contain.

  The inorganic material constituting the inorganic layer is not particularly limited, and for example, various inorganic compounds such as metals or inorganic oxides, nitrides, oxynitrides, and the like can be used. As an element constituting the inorganic material, silicon, aluminum, magnesium, titanium, tin, indium and cerium are preferable, and one or two or more of these may be included. Specific examples of the inorganic compound include silicon oxide, silicon oxynitride, aluminum oxide, magnesium oxide, titanium oxide, tin oxide, indium oxide alloy, silicon nitride, aluminum nitride, and titanium nitride. As the inorganic layer, a metal film such as an aluminum film, a silver film, a tin film, a chromium film, a nickel film, or a titanium film may be provided.

Among the above materials, silicon nitride, silicon oxide, or silicon oxynitride is particularly preferable. Since the inorganic layer made of these materials has good adhesion to the organic layer, even when the inorganic layer has pinholes, the organic layer can effectively fill the pinholes, and the barrier property is further improved. This is because it can be further increased.
Furthermore, among the above materials, silicon nitride is most preferable. That is, the inorganic layer is preferably substantially composed of silicon nitride, and the inorganic layer more preferably contains 80% by mass or more, and particularly preferably 90% by mass or more of silicon nitride. Although there is a part depending on the film forming method, silicon nitride has a dense structure as compared with silicon oxide, so that higher oxygen barrier properties can be expected. In addition, silicon nitride is excellent in abrasion resistance and bending resistance, as in the case where it is used for ceramic coating. This is because, even in contact, it is difficult to cause defects due to the destruction of the inorganic layer, and a barrier layer having excellent handling in production is provided.

  As described above, the inorganic layer closest to the light conversion layer is preferably formed by vapor deposition. Specifically, a vacuum deposition method in which an inorganic material such as an inorganic oxide, an inorganic nitride, an inorganic oxynitride, or a metal is heated and vapor-deposited on a substrate; an oxygen gas is introduced using the inorganic material as a raw material Oxidation reaction vapor deposition method of oxidizing and vapor-depositing on a base material; Sputtering method of using an inorganic material as a target raw material, introducing argon gas and oxygen gas and sputtering to deposit on the base material; Inorganic material When a vapor deposition film of silicon oxide is formed by a physical vapor deposition method (physical vapor deposition method) such as ion plating, which is heated by a plasma beam generated by a plasma gun and deposited on a substrate, Plasma Chemical Vapor Deposition Method Using Organic Silicon Compound as Raw Material (Chemical Vapor Deposition Method) Etc. The.

  The silicon oxide film can also be formed by using a low temperature plasma chemical vapor deposition method using an organosilicon compound as a raw material. Specific examples of the organosilicon compound include 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane, vinyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, and propyl. Examples thereof include silane, phenylsilane, vinyltriethoxysilane, tetramethoxysilane, phenyltriethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane. Among the organosilicon compounds, tetramethoxysilane (TMOS) and hexamethyldisiloxane (HMDSO) are preferably used. This is because these are excellent in handleability and vapor deposition film characteristics.

  The thickness of the inorganic layer closest to the light conversion layer is preferably 10 nm to 500 nm, more preferably 10 nm to 300 nm, and particularly preferably 10 nm to 150 nm. When the film thickness of the inorganic layer closest to the light conversion layer is within the above-described range, it is possible to suppress reflection in the inorganic layer while realizing good barrier properties, and light conversion with higher light transmittance. It is because a member can be provided.

<Adhesion improvement layer>
In one aspect of the light conversion member of the present invention, an adhesion improving layer can be provided between the inorganic layer and the light conversion layer. The adhesion improving layer further contains an adhesion improving agent. The adhesion improving layer has a mixed region of the adhesion improving layer component and the light converting layer component on the surface of the light converting layer side.

  As a material for the adhesion improving layer, the same (meth) acrylate monomer, epoxy monomer, or combination of an epoxy monomer and an amine as the polymerizable compound used in the light conversion layer can be used. Further, as the adhesion improving agent, the above-described adhesion improving agent can be used. In addition, a radical polymerization initiator can be added to the (meth) acrylate monomer, a cationic polymerization initiator can be added to the epoxy monomer, and other various materials described above.

The thickness of the adhesion improving layer is preferably 100 nm to 10 μm, more preferably 200 nm to 5 μm, and particularly preferably 300 nm to 3 μm. When the thickness of the adhesion improving layer is within the above-mentioned range, the adhesion between the inorganic layer and the light conversion layer is improved while minimizing the increase in thickness. This is because the decrease can be suppressed. Note that the adhesion improving layer in the light conversion member of the present invention exhibits its effect by forming a mixed region of the adhesion improving layer component and the light conversion layer component on the surface of the light conversion layer. In the form of the conversion member, the adhesion improving layer is defined as including a mixed region of the adhesion improving layer component (or adhesion improving layer precursor component) and the light conversion layer component. That is, in one aspect of the light conversion member of the present invention, a layer containing only the adhesion improving layer component (or adhesion improving layer precursor component), a mixed region of the adhesion improving layer component and the light conversion layer component, and the light conversion layer And are adjacent in this order. In this embodiment, the adhesion improving layer includes only the adhesion improving layer component and the mixed region of the adhesion improving layer component and the light conversion layer component. In another embodiment of the present invention, the mixed region of the adhesion improving layer component and the light conversion layer component, and the light conversion layer are laminated in this order, and there is no layer having only the adhesion improving layer component ( There may also be an adhesion improving layer of a mode in which a mixed region is formed over the entire adhesion improving layer. In this embodiment, the adhesion improving layer refers to a mixed region of the adhesion improving layer component and the light conversion layer component.
The thickness of the mixed region is preferably 30 nm to 4 μm, more preferably 50 nm to 2 μm, and particularly preferably 80 nm to 1 μm from the viewpoint of strengthening the adhesion between the adhesion improving layer and the light conversion layer. . However, regarding the upper limit value, when the adhesion improving layer is thin and less than the above-described value, the thickness of the adhesion improving layer is the maximum value. That is, this is an aspect in which the mixed region is formed over the entire adhesion improving layer.
In measuring the film thicknesses of the adhesion improving layer, the mixed region, and the light conversion layer, the interface between the adhesion improving layer component-only layer and the mixed region is closest to the light conversion layer from the light conversion layer in the light conversion material. Analyzing the cross-section across the inorganic layer with a surface analysis method such as TOF-SIMS, from the distribution of elements or fragment ions on the scanning line from the portion corresponding to the light conversion layer to the inorganic layer closest to the light conversion layer The light conversion layer component is not recognized.
Further, in measuring the film thicknesses of the adhesion improving layer, the mixed region, and the light conversion layer, the interface between the light conversion layer and the mixed region starts from the portion corresponding to the light conversion layer in the same manner as described above. The interface is specified from the distribution of the element or fragment ions on the scanning line up to the inorganic layer closest to, and the adhesion improving layer component is not recognized.

The adhesion improving layer can be provided by the various application methods described above. As described above, from the viewpoint of reducing damage to the inorganic layer, a coating method in which the coater and the support are non-contact is preferable. The curing conditions can be appropriately set according to the type of polymerizable compound used and the composition of the polymerizable composition.
The mixed region is obtained by providing a polymerizable composition for forming a light conversion layer on the surface of the adhesion improving layer precursor using a polymerizable composition for forming a light conversion layer containing at least a polymerizable compound having a molecular weight of 400 or less. It can be formed by converting the adhesion improving layer precursor into an adhesion improving layer having a mixed region of the adhesion improving layer precursor component and the light converting layer component on the surface of the light conversion layer. More preferably, the mixed region is cured after directly applying the polymerizable composition for forming the light conversion layer containing the light conversion layer material on the barrier film in which the material of the adhesion improvement layer (adhesion improvement layer precursor) is provided in advance. By doing so, the polymerizable compound contained in the light conversion layer material can be formed by penetrating into the adhesion improving layer provided in advance on the barrier film. Thereby, a mixed region having a structure in which the adhesion improving layer component and the light conversion layer material are entangled in a complicated manner is formed, and strong adhesion is expressed between the two layers.

<Other inorganic layers and organic layers>
The above-described light conversion member may have one or more layers selected from the group consisting of an inorganic layer and an organic layer on the surface of the inorganic layer closest to the light conversion layer opposite to the surface in direct contact with the light conversion layer. . In addition, the light conversion layer may have one or more layers selected from the group consisting of an inorganic layer and an organic layer on the surface opposite to the surface in direct contact with the inorganic layer closest to the light conversion layer. Laminating a plurality of layers in this manner is preferable from the viewpoint of improving light resistance because the barrier property can be further enhanced. On the other hand, as the number of layers to be stacked increases, the light transmittance of the light conversion member decreases and tends to lower the front luminance when incorporated in a liquid crystal display device. Therefore, the light conversion member has a good light transmittance. It is desirable to increase the number of stacked layers within a range that can be maintained. Specifically, the light conversion member preferably has an oxygen permeability of 1.00 cm ³ / (m ² · day · atm) or less. Here, the oxygen permeability is a value measured using an oxygen gas permeability measuring device (manufactured by MOCON, OX-TRAN 2/20: trade name) under the conditions of a measurement temperature of 23 ° C. and a relative humidity of 90%. It is.
The oxygen permeability is more preferably 0.10 cm ³ / (m ² · day · atm) or less, and still more preferably 0.01 cm ³ / (m ² · day · atm) or less.

  The inorganic layer provided as the other layer is as described for the inorganic layer closest to the light conversion layer. Of the other layers, the layer adjacent to the light conversion layer is not necessarily limited to the layer in direct contact with the light conversion layer. For example, the light conversion layer can be bonded to another layer adjacent to the adhesive layer.

  As the organic layer, paragraphs 0020 to 0042 of JP-A-2007-290369 and paragraphs 0074 to 0105 of JP-A-2005-096108 can be referred to. The organic layer preferably contains a cardo polymer. As a result, the adhesion between the organic layer and the adjacent layer or substrate (details will be described later), in particular, the adhesion with the inorganic layer is improved, and even better gas barrier properties can be realized. is there. For details of the cardo polymer, reference can be made to paragraphs 0085 to 0095 of the above-mentioned JP-A-2005-096108. The thickness of the organic layer is preferably in the range of 0.05 μm to 10 μm, and more preferably in the range of 0.5 to 10 μm. When the organic layer is formed by a wet coating method, the film thickness of the organic layer is preferably in the range of 0.5 to 10 μm, and more preferably in the range of 1 μm to 5 μm. Moreover, when formed by the dry coating method, it is preferable that it exists in the range of 0.05 micrometer-5 micrometers, especially in the range of 0.05 micrometer-1 micrometer. This is because when the film thickness of the organic layer formed by the wet coating method or the dry coating method is within the above-described range, the adhesion with the inorganic layer can be further improved.

  Regarding the other details of the inorganic layer and the organic layer having a barrier property, the description of the above-mentioned JP-A-2007-290369, JP-A-2005-096108, and US2012 / 0113672A1 can be referred to.

<Base material>
In addition, a substrate may be present between the organic layer and the inorganic layer, between the two organic layers, or between the two inorganic layers for improving the strength, easiness of film formation, and the like. . The substrate is preferably a transparent substrate that is transparent to visible light. Here, “transparent to visible light” means that the linear transmittance in the visible light region is 80% or more, preferably 85% or more. The light transmittance used as a measure of transparency is measured by measuring the total light transmittance and the amount of scattered light using the method described in JIS-K7105, that is, using an integrating sphere light transmittance measuring device, and diffusing transmission from the total light transmittance. It can be calculated by subtracting the rate. Regarding the substrate, paragraphs 0046 to 0052 of JP 2007-290369 A and paragraphs 0040 to 0055 of JP 2005-096108 A can be referred to. The thickness of the substrate is preferably in the range of 10 μm to 500 μm, more preferably in the range of 20 to 400 μm, and particularly preferably in the range of 30 to 300 μm, from the viewpoint of gas barrier properties, impact resistance and the like.

<Adhesive layer, adhesive material>
You may bond together between an organic layer and an inorganic layer, between two organic layers, or between two inorganic layers with a well-known adhesive layer or an adhesive material. From the viewpoint of improving the light transmittance of the light conversion member for increasing the front luminance when incorporated in a liquid crystal display device, the smaller the number of adhesive layers, the more preferable the absence of adhesive layers.

[Backlight unit]
A backlight unit according to one embodiment of the present invention includes at least the above-described light conversion member and a light source. The details of the light conversion member are as described above.

(Emission wavelength of backlight unit)
The backlight unit uses a three-wavelength light source to achieve high brightness and high color reproducibility.
Blue light having an emission center wavelength in a wavelength band of 430 to 480 nm and a peak of emission intensity having a half width of 100 nm or less;
Green light having an emission center wavelength in a wavelength band of 500 to 600 nm and a peak of emission intensity having a half width of 100 nm or less;
Red light having an emission center wavelength in a wavelength band of 600 to 680 nm and a peak of emission intensity having a half-value width of 100 nm or less;
It is preferable to emit light.
From the viewpoint of further improving luminance and color reproducibility, the wavelength band of blue light emitted from the backlight unit is preferably 430 to 480 nm, and more preferably 440 to 460 nm.
From the same viewpoint, the wavelength band of the green light emitted from the backlight unit is preferably 520 to 560 nm, and more preferably 520 to 545 nm.
From the same viewpoint, the wavelength band of red light emitted from the backlight unit is preferably 600 to 680 nm, and more preferably 610 to 640 nm.

  From the same viewpoint, the half-value widths of the emission intensity of blue light, green light, and red light emitted from the backlight unit are all preferably 80 nm or less, more preferably 50 nm or less, and 40 nm or less. More preferably, it is more preferably 30 nm or less. Among these, it is particularly preferable that the half-value width of each emission intensity of blue light is 25 nm or less.

The backlight unit includes a light source together with at least the light conversion member. In one embodiment, a light source that emits blue light having an emission center wavelength in a wavelength band of 430 nm to 480 nm, for example, a blue light emitting diode that emits blue light can be used. When using a light source that emits blue light, the light conversion layer may include at least quantum dots (A) that are excited by excitation light and emit red light, and quantum dots (B) that emit green light. preferable. Thereby, white light can be embodied by blue light emitted from the light source and transmitted through the light conversion member, and red light and green light emitted from the light conversion member.
Alternatively, in another aspect, a light source that emits ultraviolet light having an emission center wavelength in a wavelength band of 300 nm to 430 nm, for example, an ultraviolet light emitting diode can be used. In this case, it is preferable that the light conversion layer includes quantum dots (C) that are excited by excitation light and emit blue light together with the quantum dots (A) and (B). Thereby, white light can be embodied by red light, green light, and blue light emitted from the light conversion member.
In another aspect, two types of light sources selected from the group consisting of a blue laser that emits blue light, a green laser that emits green light, and a red laser that emits red light are used. By having quantum dots emitting fluorescent light with different emission wavelengths in the light conversion layer, white light is realized by two types of light emitted from the light source and light emitted from the quantum dots in the light conversion layer It can also be converted.
Among these, in the backlight unit of the present invention, the light source preferably has an emission center wavelength in a wavelength band of 380 nm to 480 nm, and more preferably has an emission center wavelength in a wavelength band of 430 nm to 480 nm.

(Configuration of backlight unit)
The configuration of the backlight unit may be an edge light system using a light guide plate, a reflection plate, or the like as a constituent member. Although FIG. 1 shows an example of an edge light type backlight unit, the backlight unit according to one embodiment of the present invention may be a direct type. Any known light guide plate can be used without any limitation.

  The backlight unit can also include a reflecting member at the rear of the light source. There is no restriction | limiting in particular as such a reflecting member, A well-known thing can be used, and it is described in patent 3416302, patent 3363565, patent 4091978, patent 3448626, etc., The content of these gazettes is this Incorporated into the invention.

It is also preferable that the backlight unit has a blue wavelength selection filter that selectively transmits light having a wavelength shorter than 460 nm of blue light.
It is also preferable that the backlight unit has a red wavelength selection filter that selectively transmits light having a wavelength longer than 630 nm out of red light.
There is no restriction | limiting in particular as such a blue wavelength selection filter or a red wavelength selection filter, A well-known thing can be used. Such a filter is described in Japanese Patent Application Laid-Open No. 2008-52067, etc., and the content of this publication is incorporated in the present invention.

  In addition, the backlight unit preferably includes a known diffusion plate, diffusion sheet, prism sheet (for example, BEF series manufactured by Sumitomo 3M Limited), and a light guide. Other members are also described in Japanese Patent No. 3416302, Japanese Patent No. 3363565, Japanese Patent No. 4091978, Japanese Patent No. 3448626, and the contents of these publications are incorporated in the present invention.

[Liquid Crystal Display]
A liquid crystal display device according to one embodiment of the present invention includes at least the above-described backlight unit and a liquid crystal cell.

(Configuration of liquid crystal display device)
The driving mode of the liquid crystal cell is not particularly limited, and is twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), and optically compensated bend cell (OCB). Various modes such as can be used. The liquid crystal cell is preferably VA mode, OCB mode, IPS mode, or TN mode, but is not limited thereto. As an example of the configuration of the VA mode liquid crystal display device, the configuration shown in FIG. However, the specific configuration of the liquid crystal display device is not particularly limited, and a known configuration can be adopted.

  In one embodiment of the liquid crystal display device, a liquid crystal cell having a liquid crystal layer sandwiched between substrates provided with electrodes on at least one of the opposite sides is provided, and the liquid crystal cell is arranged between two polarizing plates. The liquid crystal display device includes a liquid crystal cell in which liquid crystal is sealed between upper and lower substrates, and displays an image by changing the alignment state of the liquid crystal by applying a voltage. Furthermore, it has an accompanying functional layer such as a polarizing plate protective film, an optical compensation member that performs optical compensation, and an adhesive layer as necessary. In addition to (or instead of) color filter substrates, thin layer transistor substrates, lens films, diffusion sheets, hard coat layers, antireflection layers, low reflection layers, antiglare layers, etc., forward scattering layers, primer layers, antistatic layers Further, a surface layer such as an undercoat layer may be disposed.

FIG. 2 illustrates an example of a liquid crystal display device according to one embodiment of the present invention. The liquid crystal display device 51 shown in FIG. 2 has the backlight side polarizing plate 14 on the surface of the liquid crystal cell 21 on the backlight side. The backlight-side polarizing plate 14 may or may not include the polarizing plate protective film 11 on the backlight-side surface of the backlight-side polarizer 12, but it is preferably included.
The backlight side polarizing plate 14 preferably has a configuration in which the polarizer 12 is sandwiched between two polarizing plate protective films 11 and 13.
In this specification, the polarizing plate protective film on the side closer to the liquid crystal cell with respect to the polarizer is referred to as the inner side polarizing plate protective film, and the polarizing plate protective film on the side farther from the liquid crystal cell with respect to the polarizer is referred to as the outer side polarizing plate. It is called a protective film. In the example shown in FIG. 2, the polarizing plate protective film 13 is an inner side polarizing plate protective film, and the polarizing plate protective film 11 is an outer side polarizing plate protective film.

  The backlight side polarizing plate may have a retardation film as an inner side polarizing plate protective film on the liquid crystal cell side. As such a retardation film, a known cellulose acylate film or the like can be used.

  The liquid crystal display device 51 includes a display side polarizing plate 44 on the surface of the liquid crystal cell 21 opposite to the surface on the backlight side. The display-side polarizing plate 44 has a configuration in which a polarizer 42 is sandwiched between two polarizing plate protective films 41 and 43. The polarizing plate protective film 43 is an inner side polarizing plate protective film, and the polarizing plate protective film 41 is an outer side polarizing plate protective film.

  The backlight unit 31 included in the liquid crystal display device 51 is as described above.

  There is no particular limitation on the liquid crystal cell, the polarizing plate, the polarizing plate protective film, and the like constituting the liquid crystal display device according to one embodiment of the present invention, and those prepared by known methods and commercially available products can be used without any limitation. it can. It is of course possible to provide a known intermediate layer such as an adhesive layer between the layers.

-Color filter-
When a light source having an emission center wavelength in a wavelength band of 500 nm or less is used, various known methods can be used as the RGB pixel forming method. For example, a desired black matrix and R, G, and B pixel patterns can be formed on a glass substrate by using a photomask and a photoresist, and colored inks for R, G, and B pixels can be used. Using a black matrix having a predetermined width and an area (a concave portion surrounded by convex portions) divided by a black matrix wider than the width of the black matrix every n pieces, using an inkjet printer It is also possible to produce a color filter composed of R, G, and B patterns by discharging the ink composition until the density reaches a predetermined density. After image coloring, each pixel and the black matrix may be completely cured by baking or the like.
Preferred characteristics of the color filter are described in Japanese Patent Application Laid-Open No. 2008-083611 and the like, and the content of this publication is incorporated in the present invention.
For example, it is preferable that one wavelength is 590 nm to 610 nm and the other wavelength is 470 nm to 500 nm in the color filter showing green. In addition, it is preferable that one wavelength of the color filter exhibiting green has a transmittance that is half of the maximum transmittance is 590 nm to 600 nm. Furthermore, it is preferable that the maximum transmittance of the color filter showing green is 80% or more. In the color filter exhibiting green, the wavelength having the maximum transmittance is preferably 530 nm or more and 560 nm or less.
In the color filter showing green, the transmittance at the wavelength of the emission peak is preferably 10% or less of the maximum transmittance.
The color filter exhibiting red color preferably has a transmittance of 580 nm or more and 590 nm or less of 10% or less of the maximum transmittance.
As the color filter pigment, known pigments can be used without any limitation. Currently, pigments are generally used. However, color filters using dyes may be used as long as they are pigments that can control spectroscopy and ensure process stability and reliability.

-Black matrix-
In the liquid crystal display device, it is preferable that a black matrix is disposed between the pixels. Examples of the material for forming the black stripe include a material using a sputtered film of a metal such as chromium, and a light-shielding photosensitive composition in which a photosensitive resin and a black colorant are combined. Specific examples of the black colorant include carbon black, titanium carbon, iron oxide, titanium oxide, graphite, and the like. Among these, carbon black is preferable.

-Thin layer transistor-
The liquid crystal display device can further include a TFT substrate having a thin layer transistor (hereinafter also referred to as TFT). The thin film transistor preferably includes an oxide semiconductor layer having a carrier concentration of less than 1 × 10 ¹⁴ / cm ³ . A preferred embodiment of the thin layer transistor is described in Japanese Patent Application Laid-Open No. 2011-141522, and the content of this publication is incorporated in the present invention.

  The liquid crystal display device according to one embodiment of the present invention described above includes a backlight unit that includes a light conversion member that can increase the front luminance when incorporated in the liquid crystal display device and has excellent light resistance. In addition, high color reproducibility can be realized over a long period of time.

  Hereinafter, the present invention will be described more specifically based on examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

I. Production of light conversion member

Example 1
1. Production of Barrier Supports 10 and 11 A polyethylene naphthalate film (Teonex Q65FA manufactured by Teijin DuPont Co., Ltd., thickness 100 μm, width 1000 mm) is set on the delivery part of a vacuum film-forming apparatus and evacuated, and then an inorganic layer ( As the inorganic layer 1), a SiN film (film thickness 50 nm) was vapor-deposited only on one side of the polyethylene terephthalate film, and a roll film of the barrier support 10 in which the inorganic layer 100 was laminated only on one side was produced.
Separately, a barrier support 11 having an inorganic layer 101 only on one side of a polyethylene naphthalate film was prepared by the same method.

2. Preparation of Light Conversion Layer (Organic Layer Containing Quantum Dots) 1 The following quantum dot dispersion 1 was prepared and filtered through a polypropylene filter having a pore size of 0.2 μm, and then dried under reduced pressure for 30 minutes and used as a coating solution. .

───────────────────────────────────────
Quantum dot dispersion 1 (composition for organic layer 1 containing quantum dots and silane coupling agent)
───────────────────────────────────────
Toluene dispersion of quantum dots 1 (light emission maximum: 530 nm) 10 parts by weight Toluene dispersion of quantum dots 2 (light emission maximum: 620 nm) 1 part by weight lauryl methacrylate 2.4 parts by weight trimethylolpropane triacrylate 0.54 parts by weight light 0.009 parts by mass of polymerization initiator (Irgacure 819 (manufactured by BASF)
Silane coupling agent C 0.09 parts by mass────────────────────────────────────────

（上記において、ＲはＣＨ₂ＣＨＣＯＯＣＨ₂を表す。シランカップリング剤Ｃは、特開２００９−６７７７８号公報に記載の方法を参考にして合成した。）
量子ドット１、２としては、下記のコア−シェル構造（ＩｎＰ／ＺｎＳ）を有するナノ結晶を用いた。
量子ドット１：ＩＮＰ５３０−１０（ＮＮ−ｌａｂｓ社製)：蛍光半値幅６５ｎｍ
量子ドット２：ＩＮＰ６２０−１０（ＮＮ−ｌａｂｓ社製)：蛍光半値幅７０ｎｍ

(In the above, R represents CH ₂ CHCOOCH _{2. The} silane coupling agent C was synthesized with reference to the method described in JP-A-2009-67778.)
As the quantum dots 1 and 2, nanocrystals having the following core-shell structure (InP / ZnS) were used.
Quantum dot 1: INP530-10 (manufactured by NN-labs): fluorescence half width of 65 nm
Quantum dot 2: INP620-10 (manufactured by NN-labs): fluorescence half width 70 nm

Above 1. One of the barrier supports (barrier support 10) prepared in Step 1 was used as a support, and the quantum dot dispersion 1 was applied on the surface of the inorganic layer 100 of the barrier support 10. Using a 160 W / cm ² air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen, the light conversion layer 1 having a thickness of 280 μm was formed by irradiation with ultraviolet rays.
Further, the above 1. The surface of the inorganic layer 101 of the other barrier support 11 produced in the above and the surface of the light conversion layer 1 were adhered by a laminating process to produce the light conversion member 1 having the configuration shown in FIG.

(Example 2)
1. Production of Barrier Supports 20 and 21 The barrier support 20 having the inorganic layer 200 only on one side of the polyethylene naphthalate film was produced in the same manner as described above.
Separately, a barrier support 21 having an inorganic layer 203 only on one side of a polyethylene naphthalate film was produced by the same method.

2. Preparation of Barrier Supports 22 and 23 After preparing the following polymerizable composition (coating liquid for forming the organic layers 201 and 204), it was filtered through a polypropylene filter having a pore size of 0.2 μm and used as a coating liquid. Above 1. After coating on the surface of the inorganic layer 200 of the barrier support 20 produced in step 1 and fixing with irradiation of ultraviolet rays using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm ² under nitrogen, winding is performed. Then, a roll film in which an organic layer 201 was further laminated on the inorganic layer 200 was produced. The film thickness of the organic layer 201 was 1 μm.
After the roll film is set on the delivery portion of the vacuum film forming apparatus and evacuated, a SiN film (film thickness 50 nm) is deposited as an inorganic layer 202 only on the surface of the organic layer 201 by a CVD method. A film was prepared.
Separately, the barrier film 21 was similarly treated to produce a roll film of the barrier support 23 having the inorganic layer 203, the organic layer 204, and the inorganic layer 205 in this order on the polyethylene naphthalate film.

───────────────────────────────────────
Polymerizable composition (coating liquid for forming organic layers 201 and 204)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (Irgacure 819 (manufactured by BASF)
Methyl ethyl ketone 300 parts by mass ────────────────────────────────────────

3. Production of light conversion member 2 2. The quantum dot dispersion liquid 1 (composition for organic layer 1 containing quantum dots) prepared in Example 1 was used on the surface of the inorganic layer 202 of the barrier support 22 using the barrier support 22 prepared in Step 1 as a support. Was applied. Using a 160 W / cm ² air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) while purging with nitrogen, it was cured by irradiating with ultraviolet rays, and a light conversion layer (organic layer containing quantum dots) having a thickness of 280 μm 1 Formed.
Further, the above 2. The surface of the inorganic layer 205 of the barrier support 23 produced in the above and the surface of the light conversion layer 1 were adhered by a laminating process to produce the light conversion member 2 having the configuration shown in FIG.

(Comparative Example 1)
1. Preparation of Light Conversion Layer 2 Containing No Silane Coupling Agent The following quantum dot dispersion 2 was prepared, filtered through a polypropylene filter having a pore size of 0.2 μm, and then dried under reduced pressure for 30 minutes to be used as a coating solution. After applying this coating solution on a glass substrate, it was fixed by irradiation with ultraviolet rays using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm ² under nitrogen, and then peeled from the glass substrate. A light conversion layer (an organic layer containing quantum dots) 2 was prepared. The film thickness of the organic layer 2 was 280 μm.

───────────────────────────────────────
Quantum dot dispersion 2 (composition for organic layer 2 containing quantum dots)
───────────────────────────────────────
Toluene dispersion of quantum dots 1 (light emission maximum: 530 nm) 10 parts by weight Toluene dispersion of quantum dots 2 (light emission maximum: 620 nm) 1 part by weight lauryl methacrylate 2.4 parts by weight trimethylolpropane triacrylate 0.54 parts by weight light 0.009 parts by mass of polymerization initiator (Irgacure 819 (manufactured by BASF)
───────────────────────────────────────

2. Production of light conversion member 3 Both surfaces of the light conversion layer 2 prepared in Step 1 were bonded to the surfaces of the inorganic layers 100 and 101 of the barrier supports 10 and 11 prepared in Example 1 by a laminating process, and the light conversion member 3 shown in FIG. 5 was prepared.

(Comparative Example 2)
Both surfaces of the light change layer 2 produced in Comparative Example 1 were bonded to the surfaces of the inorganic layers 202 and 205 of the barrier supports 22 and 23 produced in Example 2 by a laminating process, and the light conversion member 4 shown in FIG. Produced.

(Example 3)
A light conversion member 5 having the same configuration as that of FIG. 3 was produced in the same manner as in Example 1 except that the following quantum dot dispersion 3 was used instead of the quantum dot dispersion 1.
───────────────────────────────────────
Quantum dot dispersion 3 (composition for organic layer 3 containing quantum dots and phosphoric acid monomer)
───────────────────────────────────────
Toluene dispersion of quantum dots 1 (light emission maximum: 530 nm) 10 parts by weight Toluene dispersion of quantum dots 2 (light emission maximum: 620 nm) 1 part by weight lauryl methacrylate 2.4 parts by weight trimethylolpropane triacrylate 0.54 parts by weight light 0.009 parts by mass of polymerization initiator (Irgacure 819 (manufactured by BASF)
Phosphoric acid group-containing monomer D 0.30 parts by mass────────────────────────────────────────
As phosphoric acid group-containing monomer D, KAYAMER PM-21 (the following chemical structural formula) available from Nippon Kayaku Co., Ltd. was used.

Example 4
A light conversion member 6 having the same configuration as that of FIG. 3 was produced in the same manner as in Example 1 except that the following quantum dot dispersion 4 was used instead of the quantum dot dispersion 1.
───────────────────────────────────────
Quantum dot dispersion 4
───────────────────────────────────────
Toluene dispersion of quantum dots 1 (light emission maximum: 530 nm) 10 parts by weight Toluene dispersion of quantum dots 2 (light emission maximum: 620 nm) 1 part by weight lauryl methacrylate 2.4 parts by weight trimethylolpropane triacrylate 0.54 parts by weight light 0.009 parts by mass of polymerization initiator (Irgacure 819 (manufactured by BASF)
Urethane group-containing monomer E 0.30 parts by mass────────────────────────────────────────
As the urethane group-containing monomer E, urethane acrylate UA-160TM (manufactured by Shin-Nakamura Chemical Co., Ltd.) was used.

(Example 5)
A light conversion member 7 having the same configuration as that of FIG. 3 was produced in the same manner as in Example 1 except that the following quantum dot dispersion 5 was used instead of the quantum dot dispersion 1.
───────────────────────────────────────
Quantum dot dispersion 4
───────────────────────────────────────
Toluene dispersion of quantum dots 1 (light emission maximum: 530 nm) 10 parts by weight Toluene dispersion of quantum dots 2 (light emission maximum: 620 nm) 1 part by weight lauryl methacrylate 2.4 parts by weight trimethylolpropane triacrylate 0.54 parts by weight light 0.009 parts by mass of polymerization initiator (Irgacure 819 (manufactured by BASF)
Isocyanate group-containing monomer F 0.30 parts by mass─────────────────────────────────────
As the isocyanate group-containing monomer F, Karenz MOI (manufactured by Showa Denko KK) was used.

(Examples 6 to 9)
1. Preparation of Barrier Supports 30 to 33 Having an Adhesion Improvement Layer After preparing the following polymerizable composition, it was filtered through a polypropylene filter having a pore size of 0.2 μm and used as a coating solution. It is applied to the surface of the inorganic layer 100 of the barrier support 10 produced above by a die coating method, and is fixed by irradiation with ultraviolet rays using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm ² under nitrogen. After that, a roll film in which an adhesion improving layer was further laminated on the inorganic layer 100 was produced. The film thickness of the adhesion improving layer was 1 μm each. This process was repeated by changing the coating solution to obtain barrier supports 30 to 32, respectively.

───────────────────────────────────────
Polymerizable composition (coating liquid for forming barrier support 30)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (ESACURE KTO46 (Lamberti))
Methyl ethyl ketone 300 parts by mass Silane coupling agent C 3 parts by mass─────────────────────────────────── ─

───────────────────────────────────────
Polymerizable composition (coating liquid for forming barrier support 31)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (ESACURE KTO46 (Lamberti))
Methyl ethyl ketone 300 parts by weight Phosphoric group-containing monomer D 9 parts by weight ───────────────────────────────────── ──

───────────────────────────────────────
Polymerizable composition (coating liquid for forming barrier support 32)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (ESACURE KTO46 (Lamberti))
Methyl ethyl ketone 300 parts by mass Urethane group-containing monomer E 9 parts by mass

───────────────────────────────────────
Polymerizable composition (coating liquid for forming barrier support 33)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (ESACURE KTO46 (Lamberti))
Methyl ethyl ketone 300 parts by weight Isocyanate group-containing monomer F 3 parts by weight --------------------- ─

2. Production of light conversion members of Examples 6 to 9 Each of the barrier supports 30 to 33 prepared in Step 1 was used as a support, and the quantum dot dispersion 2 prepared in Comparative Example 1 was applied on the surface of the adhesion improving layer of each barrier support. Using a 160 W / cm ² air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen, it was cured by irradiating with ultraviolet rays to form a 280 μm thick light conversion layer (organic layer containing quantum dots) Formed.
Further, the surface of the inorganic layer 101 of the barrier support 11 produced as described above and the surface of the light conversion layer were adhered by a lamination process, and the light conversion member 8 (barrier support 30 using the structure shown in FIG. 6), light conversion member 9 (Example 7 using barrier support 31), light conversion member 10 (Example 8 using barrier support 32), light conversion member 11 (barrier support 33 used) Example 9) was prepared.

(Comparative Example 3)
1. Preparation of barrier support 34 Barrier support 34 was prepared in the same manner as barrier supports 30 to 33 in Examples 6 to 9 except that the polymerizable composition was changed as shown below.
───────────────────────────────────────
Polymerizable composition (coating liquid for forming barrier support 34)
───────────────────────────────────────
Trimethylolpropane triacrylate (TMPTA) 100 parts by mass photopolymerization initiator 3.3 parts by mass (ESACURE KTO46 (Lamberti))
Methyl ethyl ketone 300 parts by mass ────────────────────────────────────────
2. Production of Light Conversion Member of Comparative Example 3 A light conversion member 12 of Comparative Example 3 shown in FIG. 7 was produced in the same manner as in Examples 6 to 9 except that the barrier support 34 was used.

(Comparative Example 4)
A light conversion member 13 of Comparative Example 4 shown in FIG. 8 was produced in the same manner as in Comparative Example 1 except that the barrier support 30 was used instead of the barrier support 10 as the barrier support.

(Example 10)
The first barrier support 10 is prepared, and the quantum dot dispersion liquid 1 is applied on the inorganic layer surface 100 of the barrier support 10 by a die coater while continuously transporting at a tension of 1 m / min and 60 N / m, and 280 μm. Was formed. Next, the barrier support 10 on which the coating film is formed is wound around a backup roller, and the second barrier support 11 is laminated on the coating film so that the inorganic layer surface is in contact with the coating film. While continuously transporting the coating film with the support 11, the heating zone at 100 ° C. was passed for 3 minutes. Thereafter, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm ² , the light conversion member 14 of Example 10 shown in FIG. The irradiation amount of ultraviolet rays was 2000 mJ.

(Example 11)
The light conversion member 15 of Example 11 was formed in the same manner as Example 10 except that the barrier support 30 was used for both the first barrier support and the second barrier support.

Example 12
1. Production of Barrier Support Using Contact Coater When producing the barrier support 30, the reverse gravure is the same as the method for producing the vapor barrier support 30 except that a reverse gravure coater is used instead of the die coater. A barrier support 35 provided with an adhesion improving layer was produced by a coater.

2. Production of Light Conversion Member Using Barrier Support 35 The light conversion member 16 of Example 10 was prepared in the same manner as in Example 6 except that the barrier support 35 produced above was used instead of the barrier support 30. Produced.

(Reference Example 1 and Reference Example 2)
1. Preparation of a barrier support using silicon oxide A polyethylene naphthalate film (Teonex Q65FA manufactured by Teijin DuPont Co., Ltd., thickness: 100 μm, width: 1000 mm) is set on the delivery part of a vacuum film-forming apparatus, evacuated, and then formed into an inorganic layer by sputtering. An SiO film (film thickness 50 nm) was vapor-deposited only on one side of the polyethylene terephthalate film, and a roll film of the barrier support 40 in which the inorganic layer 400 was laminated only on one side was produced.

2. Preparation of barrier support using non-contact coater Adhesion improving layer using a die coater in the same manner as the barrier support 30 except that the barrier support 40 is used instead of the barrier support 10. The barrier support body 41 provided with was produced.
A barrier support 42 provided with an adhesion improving layer was prepared using a reverse gravure coater in the same manner as the barrier support 35 except that the barrier support 40 was used instead of the barrier support 10.

3. Production of Light Conversion Member of Reference Example 1 and Reference Example 2 The light conversion member 17 shown in FIG. 6 is obtained in the same manner as in Example 6 except that each of the barrier supports 41 and 42 is used instead of the barrier support 30. Reference Example 1 using the barrier support 41 and the light conversion member 18 (Reference Example 2 using the barrier support 42) were produced.

II. Production of liquid crystal display device A commercially available liquid crystal display device (trade name THL42D2 manufactured by Panasonic Corporation) was disassembled, the light conversion member 1 was added on the light guide plate on the side where the liquid crystal cell is located, and the backlight unit was replaced with the following B narrow-band backlight. The unit was changed to a liquid crystal display device. The used B narrow-band backlight unit includes a blue light emitting diode (Nichia B-LED: Blue, main wavelength 465 nm, half-value width 20 nm) as a light source.

  A liquid crystal display device was produced in the same manner as in Example 1 except that the light conversion member 1 was changed to the light conversion members 2 to 18.

III. Evaluation <Evaluation of light resistance>
The light resistance of the light conversion members prepared in Examples and Comparative Examples was evaluated. Light resistance uses 22mW, 465nm blue LED, 20mA current is passed through this LED package, and the laminated body is irradiated for 2000 hours continuously in the atmosphere, and the luminous efficiency of the laminated body after light irradiation is measured. did. Based on the results, evaluation was made according to the following criteria. The results are shown in Tables 1-4.
A Luminous efficiency of 80% or more compared to before light irradiation.
B Luminous efficiency of 60% or more and less than 80% compared to before light irradiation.
C Luminous efficiency of 50% or more and less than 60% compared to before light irradiation.
D Luminous efficiency of 40% or more and less than 50% compared to before light irradiation.
E Luminous efficiency of less than 40% compared to before light irradiation.

<Evaluation of oxygen permeability>
The oxygen transmissivity of the light conversion members produced in Examples and Comparative Examples was measured by the method described above. Based on the results, evaluation was made according to the following criteria. The results are shown in Tables 1-4.
A: 0.10 cm ³ / (m ² · day · atm) or less B: More than 0.10 cm ³ / (m ² · day · atm) 1.00 cm ³ / (m ² · day · atm) or less C: 1. More than 00cm ³ / (m ² · day · atm)

<Evaluation of front brightness>
The front luminance of the liquid crystal display device was measured by the method described in [0180] of JP-A-2009-93166. Based on the results, evaluation was made according to the following criteria. The results are shown in Tables 1-4.
A: 15% or more and better than the front luminance of the liquid crystal display device of Comparative Example 1 B: 10% or more and less than 15% and better than the front luminance of the liquid crystal display device of Comparative Example 1 C: Comparative Example 5% or more and less than 10%, which is better than the front luminance of the liquid crystal display device of No. 1. D: It is equal to or lower than the front luminance of the liquid crystal display device of Comparative Example 1.

<Evaluation of front contrast>
The front contrast of the liquid crystal display device was measured by the method described in [0180] of JP-A-2009-93166. Based on the results, evaluation was made according to the following criteria. The results are shown in Tables 1-4.
A: 10% or more better than the front contrast of the liquid crystal display device of Comparative Example 1 B: 5% or more and less than 10% better than the front contrast of the liquid crystal display device of Comparative Example 1 C: Comparative Example It is equal to or less than the front contrast of the liquid crystal display device 1 or 2.

<Evaluation of uneven color in oblique direction>
The color unevenness in the oblique direction of the liquid crystal display device was measured by the method described in [0079] of JP-A-2008-145868. Based on the results, evaluation was made according to the following criteria. The results are shown in Tables 1-4.
A: 30% or more better than the color unevenness of the oblique orientation of the liquid crystal display device of Comparative Example 2 B: 20% or more better than the color unevenness of the oblique orientation of the liquid crystal display device of Comparative Example 2 better than 30% Some C: 10% or more and less than 20% of color unevenness in the oblique direction of the liquid crystal display device of Comparative Example 2 D: 10% better than the color unevenness in the oblique direction of the liquid crystal display device of Comparative Example 2 Less than good.
E: It is equal to or less than the color unevenness in the oblique direction of the liquid crystal display device of Comparative Example 2.

<Evaluation of adhesion>
Evaluation was performed by a method in accordance with JIS K5400. Cuts that reach the light conversion layer at 90 ° with respect to the film surface are made at 1 mm intervals on one side of a layer (barrier layer) other than the light conversion layer of the light conversion member of each example and comparative example at intervals of 1 mm. 100 squares were prepared. On top of this, the tape affixed with a 2 cm wide Mylar tape (manufactured by Nitto Denko, polyester tape, No. 31B) was peeled off. Evaluation was made by the number of cells in which the outermost layer of the light conversion member of each example and comparative example remained. The same test was performed on both sides, and evaluation was performed according to the following evaluation criteria using the value of the side with the smaller number of cells where the outermost layer remained. The results are shown in Tables 1-4.
A: Number of remaining cells 100 B: Number of remaining cells 99 to 60 C: Number of remaining cells 59 to 20 D: Number of remaining cells 19 to 0

<Measurement of presence or absence of mixed region of adhesion improving layer and light conversion layer>
The prepared light conversion film was cut with a microtome so that the angle formed by the cut surface and the film plane was decreased and entered obliquely, and the obtained cross section was scanned in the film thickness direction with TOF-SIMS. From the obtained mass spectrum and position information, on the surface of the adhesion improving layer on the light conversion layer side, a mass peak derived from the material of the adhesion improving layer (component of the adhesion improving layer precursor) and a mass peak derived from the light converting layer If there is a region where both are detected, it is determined that a mixed region is formed on the surface of the adhesion improving layer on the light conversion layer side, and if only one of them is detected, it is determined that no mixed region is formed. . Specifically, in Examples 6 to 9, the mass peaks derived from the material of the adhesion improving layer (component of the adhesion improving layer precursor) and the light conversion layer are mass peaks caused by the initiator (or a decomposition product thereof), respectively. Was used. The results are shown in Tables 2-4.

<Evaluation results>
As shown in Tables 1 to 4, the light conversion member of each example is a light conversion member including quantum dots, which can increase the front luminance when incorporated in a liquid crystal display device, and has excellent light resistance. It turned out that it is a light conversion member which has. Details of each table will be described below.
As shown in Table 1, the light conversion members of Examples 1, 2, 3, 4, and 5 are light conversion members including quantum dots, which can increase the front luminance when incorporated in a liquid crystal display device, and It was found that the light conversion member had excellent light resistance. Further, the liquid crystal display devices provided with the light conversion members of Examples 1, 2, 3, 4, and 5 have good front luminance. Further, in the liquid crystal display device according to a preferred embodiment of the present invention, the front contrast and the color unevenness. Good results were also shown for the evaluation. This is considered to be because bubbles are hardly generated at the interface with the adjacent inorganic layer because the light conversion layer contains the adhesion improving agent. These results indicate that the fewer bubbles present at the interface between the light conversion layer and the adjacent layer, the less light is scattered within the layer, the more light goes directly to the exit surface, and the light transmission is improved. I guess that it has brought.
In addition, the light conversion members of Examples 6 to 9 are also light conversion members including quantum dots, which can increase the front luminance when incorporated in a liquid crystal display device and have excellent light resistance. I found out. Furthermore, in the liquid crystal display device according to a preferred embodiment of the present invention, good results were shown for front contrast and evaluation of color unevenness. This is considered to be because the adhesion improving layer strengthens the adhesion between the inorganic layer and the adhesion improving layer and between the adhesion improving layer and the light conversion layer, and bubbles are not easily generated between adjacent layers. . The mechanism is assumed to be the same as described above.
Further, from the results of Examples 10 and 11, it was found that the light resistance could be further improved by devising the manufacturing process. This is presumably because the time during which the light conversion layer is exposed to oxygen can be minimized.
Furthermore, as shown in Example 6 and Reference Example 1, Example 12 and Reference Example 2, the light conversion member of the present invention is stable regardless of the coating method by appropriately selecting the material of the inorganic layer. Demonstrated light resistance. This is presumed to be because the inorganic layer is damaged by the contact of the coater, but the extent is reduced by using silicon nitride as the material of the inorganic layer. Therefore, using silicon nitride as the material for the inorganic layer is extremely useful in solving the problems of the present invention more effectively.
From the above results, according to one embodiment of the present invention, when incorporated in a liquid crystal display device, the front luminance can be increased, and an image with high front luminance can be displayed, including a light conversion member having excellent light resistance. It was confirmed that a liquid crystal display device can be provided. Furthermore, according to the preferable aspect of this invention, it was confirmed that the liquid crystal display device which can display a clear image with high front contrast and few color irregularities can be provided.

DESCRIPTION OF SYMBOLS 100 Manufacturing equipment 10 1st film 20 Application | coating part 22 Coating film 24 Die coater 26 Backup roller 28 Light conversion layer (hardening layer)
30 Laminating unit 32 Laminating roller 34 Heating chamber 50 Second film 60 Curing unit 62 Backup roller 64 Ultraviolet irradiation device 70 Light conversion member 80 Peeling roller

  The present invention is useful in the field of manufacturing liquid crystal display devices.

Claims (18)

A light conversion member having a light conversion layer containing a quantum dot excited by incident excitation light and emitting fluorescence in an organic matrix ,
Having an adhesion improving layer in direct contact with the light conversion layer;
An inorganic layer in direct contact with the adhesion improving layer;
The adhesion improving layer is composed of an organic metal coupling agent, a polymerizable compound having a phosphate group, and a polymerizable compound containing in the molecule at least one of a structure selected from a urethane bond, a urea bond, and an isocyanuric ring. The adhesion improving layer is a component contained in the light conversion layer in a surface layer region on the surface side of the light conversion layer, and the adhesion improving layer. A light conversion layer component that is a component that is not included in a portion other than the surface layer region, and a component that is included in a portion other than the surface layer region of the adhesion improving layer and is not included in the light conversion layer. A light conversion member having a mixed region with an adhesion improving layer component.   The light conversion member according to claim 1, wherein the inorganic layer further has one or more layers selected from the group consisting of an inorganic layer and an organic layer on a surface opposite to the light conversion layer side.   The light conversion member according to claim 1 or 2, wherein the light conversion layer further has one or more layers selected from the group consisting of an inorganic layer and an organic layer on a surface opposite to the inorganic layer side.   The light conversion member according to claim 1, wherein the inorganic layer is substantially made of silicon nitride.   The said organic matrix is a polymer of a monofunctional (meth) acrylate monomer and a polyfunctional (meth) acrylate monomer, The light conversion member of any one of Claims 1-4.   The light conversion member according to claim 5, wherein the monofunctional (meth) acrylate monomer has a long-chain alkyl group having 4 to 30 carbon atoms. The quantum dots are
Quantum dots (A) having an emission center wavelength in a wavelength band ranging from 600 nm to 680 nm,
A quantum dot (B) having an emission center wavelength in a wavelength band in the range of 500 nm to 600 nm, and a quantum dot (C) having an emission center wavelength in a wavelength band of 400 nm to 500 nm,
The light conversion member according to claim 1, which is at least one selected from the group consisting of: The light conversion member according to any one of claims 1 to 7, wherein an oxygen permeability is 1.00 cm ³ / (m ² · day · atm) or less. The light conversion member according to any one of claims 1 to 8,
A light source;
Including at least backlight unit. Blue light having an emission center wavelength in a wavelength band of 430 to 480 nm and a peak of emission intensity having a half width of 100 nm or less;
Green light having an emission center wavelength in a wavelength band of 500 to 600 nm and a peak of emission intensity having a half width of 100 nm or less;
Red light having an emission center wavelength in a wavelength band of 600 to 680 nm and a peak of emission intensity having a half-value width of 100 nm or less;
The backlight unit according to claim 9 which emits light.   The backlight unit according to claim 9 or 10, wherein the light source has an emission center wavelength in a wavelength band of 380 to 480 nm. A light guide plate;
The backlight unit according to any one of claims 9 to 11, wherein the light conversion member is provided on a path of light emitted from the light guide plate. A light guide plate;
The backlight unit according to any one of claims 9 to 11, wherein the light conversion member is provided between the light guide plate and a light source. The backlight unit according to any one of claims 9 to 13,
A liquid crystal cell;
A liquid crystal display device comprising at least It is a manufacturing method of the light conversion member given in any 1 paragraph of Claims 1-8,
At least one of a structure selected from an organometallic coupling agent, a polymerizable compound having a phosphate group, and a urethane bond, a urea bond, and an isocyanuric ring on the surface of the inorganic layer of the first barrier film including at least the inorganic layer. Providing an adhesion improving layer precursor that is a cured layer of a polymerizable composition containing at least one adhesion improving agent selected from the group consisting of polymerizable compounds containing one in the molecule;
Providing a polymerizable composition for forming a light conversion layer containing quantum dots and a polymerizable compound on the surface of the adhesion improving layer precursor; and
A method for producing a light conversion member, comprising the step of forming the light conversion layer by polymerizing the polymerizable composition for forming the light conversion layer provided on the surface of the adhesion improving layer precursor. Before the step of forming the light conversion layer, the second barrier film is provided on the surface of the adhesion improving layer precursor of the first barrier film, and the polymerizable composition for forming the light conversion layer is provided. Including a step of placing the first barrier film in contact with the surface opposite to the side on which the first barrier film is provided,
The step of forming the light conversion layer is for forming the light conversion layer in a state where the first barrier film, the adhesion improving layer precursor, the light conversion layer, and the second barrier film are laminated in this order. The method for producing a light conversion member according to claim 15, wherein the light conversion layer is formed by polymerizing the polymerizable composition.   The manufacturing method of the light conversion member of Claim 15 or 16 including the process of heating the polymeric composition for the said light conversion layer formation before the process of forming the said light conversion layer. The polymerizable composition for forming the light conversion layer contains at least a polymerizable compound having a molecular weight of 400 or less,
By providing the polymerizable composition for forming the light conversion layer on the surface of the adhesion improving layer precursor, the polymerizable composition for forming the light conversion layer is permeated into the surface layer region of the adhesion improving layer precursor. The manufacturing method of the light conversion member as described in any one of Claims 15-17 containing this.

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