JP2013033833A - Wavelength conversion film and light emitting device and lighting device which use the same - Google Patents

Abstract

The present invention provides a wavelength conversion film that suppresses a decrease in light emission efficiency of a quantum dot phosphor due to insufficient substitution of the ligand of the quantum dot phosphor and surface separation of the ligand.
A support substrate 11, an adhesive gel layer 12a formed on the support substrate 11, and a phosphor layer 13 formed on the adhesive gel layer 12a are provided. The adhesive gel layer 12a is an adhesive layer made of gel, and the phosphor layer 13 is made of a quantum dot phosphor. Furthermore, the ligand constituting the outermost layer of the quantum dot phosphor of the phosphor layer 13 is in contact with the adhesive gel layer 12a.
[Selection] Figure 1

Description

  The present invention relates to a wavelength conversion film using a quantum dot phosphor, a light-emitting device using the same, and an illumination device.

  Developments for high efficiency and high color rendering of light-emitting devices such as white LEDs (Light Emitting Diodes) used for lighting or liquid crystal display backlights are progressing. In recent years, in order to realize such a light-emitting device, a light-emitting device that combines a blue LED that emits blue light and a quantum dot phosphor made of semiconductor fine particles has been developed.

  As shown in FIG. 10A, the quantum dot phosphor 110 includes a nano-sized compound composed of a semiconductor particle 111 composed of a core 112a made of CdSe and a shell 112b made of ZnS, for example, and a ligand 113 covering the periphery thereof. Semiconductor fine particles. This quantum dot phosphor 110 has a quantum confinement effect because its particle diameter is smaller than the Bohr radius of excitons of the compound semiconductor. Therefore, the luminous efficiency of the quantum dot phosphor is higher than that of conventionally used phosphors using rare earth ions as an activator (rare earth phosphor), and a high luminous efficiency of 90% or more can be realized. In addition, since the emission wavelength of the quantum dot phosphor is determined by the band gap energy of the compound semiconductor fine particles quantized in this way, changing the particle size of the quantum dot phosphor changes an arbitrary emission wavelength, that is, an arbitrary emission. A spectrum can be obtained. By combining these quantum dot phosphors with a blue LED, a white LED light source with high luminous efficiency and high color rendering can be realized.

  On the other hand, quantum dot phosphors have two major features that are different from conventional rare earth phosphors. One is resistance to oxygen and the other is the influence of the polarity of surrounding molecules.

  First, since the quantum dot phosphor is vulnerable to oxygen, it is usually stored in an organic solvent such as toluene 140 as shown in FIG. 10B. Specifically, the quantum dot phosphor 110 is dispersed in the toluene 140 in the container 120 and stored in a state of being completely sealed against the outside air by the lid 130.

  In order to mount this quantum dot phosphor on a white LED while maintaining high quantum efficiency, it is necessary to contain it in a medium to be dispersed (sealing resin) having a high oxygen barrier property.

  An example of a white LED using a quantum dot phosphor in a sealing resin having a high oxygen barrier property is disclosed in Patent Document 1. FIG. 11 is a cross-sectional view illustrating a configuration of a light emitting device disclosed in Patent Document 1. As shown in FIG. 11, the light-emitting device 60 disclosed in Patent Document 1 uses a resin 65b constituting the sealing resin 65 containing the quantum dot phosphor 65a using a resin having an oxygen barrier property. Thus, intrusion of moisture and gas is prevented, and deterioration of the quantum dot phosphor 65a is prevented.

  On the other hand, when the quantum dot phosphor is contained in the sealing resin, it is important to consider the influence of the polarity of the molecules constituting the sealing resin that is the medium to be dispersed. Specifically, it is necessary to consider the polarity of the ligand of the quantum dot phosphor with respect to the polarity of the molecular structure constituting the sealing resin.

  For example, Non-Patent Document 1 discloses that a nonpolar dispersion medium containing a quantum dot phosphor having a nonpolar ligand formed therein, emission intensity when the addition amount of chloroform having a larger polarity in hexane is increased. Is described as decreasing.

  Non-Patent Document 2 describes that the quantum efficiency is greatly reduced when a nonpolar ligand is replaced with a polar ligand and dispersed in water, which is a medium to be dispersed, that is larger than the polarity of the ligand.

JP 2011-29380 A

Langmuir, Vol.22, No.7, 2006, p.3007-3013 Journal of Colloid and Interface Science 339, 2009, p.336-343

  According to the above prior art, when a quantum dot phosphor is used, it is desirable to form a white LED by containing it in a nonpolar resin material having a high oxygen barrier property. However, the resin material currently used for white LEDs is silicone or epoxy, and the molecular structure of these resins has polarity. Therefore, when a quantum dot phosphor is contained in these resins, there is a problem of reducing the light emission efficiency of the quantum dot phosphor. Furthermore, silicone has a very low oxygen barrier property, and when a white LED is formed by containing a quantum dot phosphor in the silicone, the light emission efficiency of the quantum dot phosphor rapidly decreases in a short period of time.

  On the other hand, as a method of mounting a quantum dot phosphor on a white LED with a high quantum efficiency, a small container in which the quantum dot phosphor is dispersed and sealed in a nonpolar dispersion medium such as hexane is mounted and mounted. However, such a small container is difficult to handle as a white LED component and is difficult to redesign for various applications.

  The present invention has been made in view of such problems, and even when a resin having polarity is used, the light emission efficiency of the quantum dot phosphor does not decrease, and the wavelength is easy to mount as a white LED component. It is an object of the present invention to provide a conversion film, a light emitting device using the conversion film, and a lighting device.

  In order to achieve the above object, one embodiment of a wavelength conversion film according to the present invention is formed on a support substrate, a first resin layer formed on the support substrate, and the first resin layer. The first resin layer is an adhesive layer made of gel, the first phosphor layer is made of a quantum dot phosphor, and the quantum dot phosphor The ligand constituting the outermost layer is in contact with the adhesive layer.

  According to this aspect, since the ligand constituting the outermost layer of the quantum dot phosphor is in contact with the surface of the adhesive layer made of gel, the quantum dot phosphor is dispersed in a resin such as an acrylic resin or an epoxy resin. There is no need for substitution of polar ligands. As a result, it can be suppressed that the molecular polarity of the polar ligand affects the light emission efficiency of the quantum dot phosphor and the light emission efficiency of the quantum dot phosphor is reduced.

  In one embodiment of the wavelength conversion film according to the present invention, the area where the first resin layer is in contact with the support substrate is larger than the area where the first resin layer is in contact with the first phosphor layer. Is preferred.

  With this configuration, since all of the quantum dot phosphors constituting the first phosphor layer can be brought into contact with the adhesive layer, it is possible to further suppress a decrease in light emission efficiency of the quantum dot phosphors.

  Moreover, one mode of the wavelength conversion film according to the present invention further includes the second resin layer formed on the first phosphor layer, and the second resin layer is an adhesive made of gel. A layer is preferred.

  With this configuration, an adhesive layer is also formed on the upper surface of the first phosphor layer, so the outermost ligand of the quantum dot phosphor constituting the first phosphor layer is not only the lower adhesive layer, Also in contact with the upper adhesive layer. Thereby, the fall of the luminous efficiency of quantum dot fluorescent substance can be suppressed further.

  In one embodiment of the wavelength conversion film according to the present invention, the first phosphor layer includes a quantum dot phosphor having a first emission wavelength and a second emission wavelength different from the first emission wavelength. It preferably consists of a quantum dot phosphor.

  Thereby, one fluorescent substance layer can be comprised by the multiple types of quantum dot fluorescent substance from which light emission wavelength differs.

  Further, in one aspect of the wavelength conversion film according to the present invention, further comprising an oxygen barrier layer formed to cover the second resin layer, the oxygen barrier layer comprising a transparent resin containing an oxygen getter material, Or it consists of a transparent inorganic material.

  With this configuration, the reliability of the wavelength conversion film can be improved.

  Further, in one aspect of the wavelength conversion film according to the present invention, an adhesive layer that adheres the support substrate and the oxygen barrier layer is further provided, and the adhesive layer has at least an oxygen barrier property or a water vapor barrier property. It is preferably made of a molecular material.

  With this configuration, the reliability of the wavelength conversion film can be improved.

  Further, in one aspect of the wavelength conversion film according to the present invention, the device further comprises a second phosphor layer formed on the second resin layer, and the second phosphor layer is a quantum dot phosphor. It is preferable that the ligand constituting the outermost layer of the quantum dot phosphor constituting the second phosphor layer is in contact with the adhesive layer constituting the second resin layer.

  With this configuration, a wavelength conversion film including two phosphor layers made of quantum dot phosphors can be realized.

  Moreover, one mode of the wavelength conversion film according to the present invention further includes the third resin layer formed on the second phosphor layer, and the third resin layer is an adhesive made of gel. A layer is preferred.

  With this configuration, the outermost ligand of the quantum dot phosphor constituting the first phosphor layer and the second phosphor layer is in contact with any of the upper and lower adhesive layers. Thereby, the fall of the luminous efficiency of quantum dot fluorescent substance can be suppressed further.

  In the aspect of the wavelength conversion film according to the present invention, the first phosphor layer is made of a quantum dot phosphor having a first emission wavelength, and the second phosphor layer is the first light emission. It is preferably made of a quantum dot phosphor having a second emission wavelength different from the wavelength.

  With this configuration, the phosphor layer is divided into two layers for each emission wavelength, so color unevenness is suppressed compared to a single-layer phosphor layer in which two quantum dot phosphors having different emission wavelengths are mixed. A wavelength conversion film thus formed can be realized.

  Also, in one aspect of the wavelength conversion film according to the present invention, the first phosphor layer is made of a resin containing the quantum dot phosphor, and a dipole moment of a ligand constituting the outermost layer of the quantum dot phosphor. And the dipole moment of the resin is preferably the same value.

  With this configuration, the polarity of the ligand bound to the dangling bond of the quantum dot phosphor matches the polarity of the resin material that disperses the quantum dot phosphor, so that the ligand of the quantum dot phosphor is sufficiently replaced. It is possible to further suppress the absence of the ligand or the removal of the ligand. Therefore, it can suppress further that the luminous efficiency of quantum dot fluorescent substance falls.

  Another embodiment of the wavelength conversion film according to the present invention includes a support substrate, a first resin layer formed on the support substrate, and a first resin layer formed on the first resin layer. The first phosphor layer is made of a resin and a quantum dot phosphor, and the dipole moment of the ligand constituting the outermost layer of the quantum dot phosphor and the dipole moment of the resin Is the same value.

  With this configuration, the polarity of the ligand bound to the dangling bond of the quantum dot phosphor matches the polarity of the resin material that disperses the quantum dot phosphor, so that the ligand of the quantum dot phosphor is sufficiently replaced. It is possible to suppress the absence of the ligand or the release of the ligand. Therefore, it can suppress that the luminous efficiency of quantum dot fluorescent substance falls.

  One embodiment of the light emitting device according to the present invention includes a package having a recess, a light emitting element mounted in the recess, and any one of the wavelength conversion films formed on the package, and the light emitting element. The light emitted from is wavelength-converted by the wavelength conversion film.

  Thus, the wavelength conversion film according to the present invention can be realized as a light emitting device such as an LED white light source.

  One embodiment of the lighting device according to the present invention includes a light emitting element and any one of the wavelength conversion films described above, and light emitted from the light emitting element is wavelength-converted by the wavelength conversion film. .

  Thus, the wavelength conversion film according to the present invention can be realized as an illumination device such as an LED bulb.

  ADVANTAGE OF THE INVENTION According to this invention, the fall of the luminous efficiency of the quantum dot fluorescent substance by insufficient substitution of the ligand of the quantum dot fluorescent substance which is semiconductor fine particles, and detachment | leave of a ligand can be suppressed.

It is sectional drawing which shows the structure of the wavelength conversion film in the 1st Embodiment of this invention. It is sectional drawing which shows the structure of the wavelength conversion film in the 2nd Embodiment of this invention. It is sectional drawing which shows the structure of the wavelength conversion film in the 3rd Embodiment of this invention. It is sectional drawing which shows the structure of the 1st light emitting element in the 4th Embodiment of this invention. It is sectional drawing which shows the structure of the light-emitting device in the modification 1 of the 4th Embodiment of this invention. It is sectional drawing which shows the structure of the light-emitting device in the modification 2 of the 4th Embodiment of this invention. It is a partially notched side view which shows the structure of the 1st illuminating device in the 5th Embodiment of this invention. It is a partially notched side view which shows the structure of the 2nd illuminating device in the 5th Embodiment of this invention. It is a top view of the 2nd illuminating device in the 5th Embodiment of this invention. It is a partially notched side view which shows the structure of the 3rd illuminating device in the 5th Embodiment of this invention. It is a figure which shows the structure of quantum dot fluorescent substance. It is a figure which shows the preservation | save method of quantum dot fluorescent substance. It is a figure which shows the structure of the conventional light-emitting device disclosed by patent document 1. FIG.

  Embodiments of the present invention will be described below with reference to the drawings. Note that each of the embodiments described below shows a preferable specific example of the present invention, and numerical values, shapes, materials, components, component arrangement positions, and connection forms shown in the following embodiments. The steps, the order of steps, etc. are merely examples, and are not intended to limit the present invention. The present invention is specified based on the description of the claims. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept of the present invention are not necessarily required to achieve the object of the present invention. It will be described as constituting a preferred form. In the drawings, elements that represent substantially the same configuration, operation, and effect are denoted by the same reference numerals.

  In each embodiment of the present invention, the quantum dot phosphor made of semiconductor fine particles constituting the wavelength conversion film preferably emits light at a wavelength between 450 nm and 700 nm. Furthermore, the quantum dot phosphor in the present embodiment emits fluorescent light using blue light as excitation light. Among the above wavelength ranges, for example, the quantum dot phosphor emits light at a wavelength of 530 nm, and the wavelength is 620 nm. A case where a quantum dot phosphor that emits light is used will be described.

(First embodiment)
First, the wavelength conversion film 1 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view showing the configuration of the wavelength conversion film in the first embodiment of the present invention.

  As shown in FIG. 1, the wavelength conversion film 1 according to the present embodiment includes a support substrate 11, an adhesive gel layer 12a (first resin layer) formed on the support substrate 11, and an adhesive gel layer 12a. And a phosphor layer 13 (first phosphor layer) formed thereon.

  The support substrate 11 is a thin film-like transparent resin substrate, and can be composed of, for example, a resin film made of a transparent polyimide resin.

  The pressure-sensitive adhesive gel layer 12a is a pressure-sensitive adhesive layer made of gel, and can be composed of, for example, an acrylic pressure-sensitive adhesive. In the present embodiment, the adhesive gel layer 12 a is configured such that the contact area with the support substrate 11 is larger than the contact area with the phosphor layer 13.

  The phosphor layer 13 is a semiconductor fine particle layer composed of a plurality of semiconductor fine particles, and is composed of, for example, a quantum dot phosphor having a particle size of 20 nm or less. Quantum dot phosphors consist of nano-sized semiconductor particles with a particle size of several nanometers to several tens of nanometers, and the desired wavelength in the visible light region can be controlled by controlling the particle diameter even with fine particles of the same material due to the quantum size effect. A band fluorescence spectrum can be obtained. In the present embodiment, the outermost ligand of the quantum dot phosphor constituting the phosphor layer 13 is in contact with the adhesive gel layer 12a.

  Moreover, in this Embodiment, it is preferable that the wavelength conversion film 1 is provided with the adhesion gel layer 12b (2nd resin layer) formed so that the adhesion gel layer 12a and the fluorescent substance layer 13 might be covered. The adhesive gel layer 12b is formed over the upper portion and the side surface of the phosphor layer 13. The adhesive gel layer 12b is an adhesive layer made of a gel, and the same material as that of the lower adhesive gel layer 12a can be used. In the present embodiment, the pressure-sensitive adhesive gel layer 12b is made of an acrylic pressure-sensitive adhesive as with the pressure-sensitive adhesive gel layer 12a. By forming the adhesive gel layer 12b on the upper surface of the phosphor layer 13 in this way, the outermost ligand of the quantum dot phosphor constituting the phosphor layer 13 is also in contact with the adhesive gel layer 12b.

  Furthermore, in the wavelength conversion film 1, it is preferable to form the oxygen barrier layer 15 so as to cover the top and side surfaces of the adhesive gel layer 12b. The oxygen barrier layer 15 can use, for example, a silicon oxynitride film (SiON) as a transparent inorganic material, and is preferably formed with a thickness of 10 nm or more. The oxygen barrier layer 15 can also be made of a transparent resin containing an oxygen getter material.

  In the wavelength conversion film 1 according to the present embodiment, it is preferable to provide an adhesive 16 that adheres the support substrate 11 and the oxygen barrier layer 15. In the present embodiment, the adhesive 16 (adhesive layer) is formed so as to cover the side surface of the support substrate 11 and the side surface of the oxygen barrier layer 15. The adhesive 16 is preferably composed of an organic polymer material having at least an oxygen barrier property or a water vapor barrier property. For example, an epoxy adhesive can be used.

  As described above, according to the wavelength conversion film 1 according to the first embodiment of the present invention, the phosphor layer 13 made of the quantum dot phosphor (semiconductor fine particles) is directly formed on the surface of the adhesive gel layer 12a. In particular, in the present embodiment, the ligand constituting the outermost layer of the quantum dot phosphor of the phosphor layer 13 is in contact with the surface of the adhesive gel layer 12a. This eliminates the need for replacing the ligand that has been processed in order to disperse the quantum dot phosphor in a resin such as an acrylic resin or an epoxy resin, as in the prior art. For this reason, lack of substitution of the ligand can be eliminated and the detachment of the ligand can also be suppressed. Therefore, it is possible to realize a wavelength conversion film that can suppress a decrease in light emission efficiency of the quantum dot phosphor.

  Moreover, in this Embodiment, the fluorescent substance layer 13 which consists of quantum dot fluorescent substance (semiconductor microparticles | fine-particles) is also in contact with the adhesion gel layer 12b. Thereby, the fall of the luminous efficiency of quantum dot fluorescent substance can further be suppressed.

  In the present embodiment, the contact area between the adhesive gel layer 12 a and the support substrate 11 is configured to be larger than the contact area between the adhesive gel layer 12 a and the phosphor layer 13. Thereby, since all the quantum dot fluorescent substances which comprise the fluorescent substance layer 13 can be made to contact with the adhesion gel layer 12a, the fall of the luminous efficiency of quantum dot fluorescent substance can further be suppressed.

  In this embodiment, acrylic pressure-sensitive adhesives are used as the adhesive gel layers 12a and 12b. However, the present invention is not limited to this. Other examples of the adhesive gel layers 12a and 12b include urethane adhesives, rubber adhesives, silicone adhesives, polyester adhesives, polyamide adhesives, epoxy adhesives, vinyl alkyl ether adhesives, or A known pressure-sensitive adhesive such as a fluorine-based pressure-sensitive adhesive can be used.

Further, as described above, the oxygen barrier layer 15 can be made of a transparent inorganic material or a transparent organic material to which an oxygen getter material is added. In this embodiment, a silicon oxynitride film is used as the transparent inorganic material, but silicon oxide (SiO ₂ ), indium oxide added with tin (ITO), tin oxide added with antimony, or oxidation Zinc can also be used. On the other hand, when the oxygen barrier layer 15 is formed of a transparent organic material, for example, an acrylic resin, a silicone resin, an epoxy resin, a polyamide resin, a polyester resin, a vinyl alkyl ether resin using an electrodeposition technique, or Fluorine resin can be used. Further, when a transparent organic material is used, examples of an oxygen getter material that adsorbs oxygen therein include titanium oxide (TiO _x ), niobium oxide (NbO _x ), hafnium oxide (HfO _x ), and indium oxide. (In ₂ O _x ), tungsten oxide (WO _x ), tin oxide (SnO _x ), zinc oxide (ZnO _x ), zirconia oxide (ZrO _x ), magnesium oxide (MgO), antimony oxide ( It is preferable to add SbO _x ), zeolite (aluminosilicate), silver oxide (Ag ₂ O), or the like. In each composition formula, all are x> 0.

  In this embodiment, a transparent polyimide resin is used as the support substrate 11, but a non-conductive transparent resin film, a conductive transparent resin film, a conductive transparent metal film, a transparent glass substrate, a sapphire substrate, a GaN substrate, Alternatively, a SiC substrate may be used.

  In addition, examples of the configuration of the quantum dot phosphor in the phosphor layer 13 include a core type, a core / shell type, and a quantum well type, but any configuration can be applied in the present embodiment. .

  In addition, as a material of the core and shell constituting the quantum dot phosphor, for example, in the case of a II-VI group compound, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS , CdSeTe, CdSTe, ZnSeS, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnZe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnZeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, CdHgSeTe, CdHgSTe, HgZnSS , HgZnSeTe, HgZnSTe, and the like.

  In the case of III-V group compounds, GaN, GaP, GaAs, GaSb, AlN, AlGaN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, InGaN, GaNP, GANAS, GaNSb, GaPAs, GaPSb, AlNP. AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, InAlNSIn, InAlNP, InAlNSIn At least one of them.

  Next, a method for manufacturing the wavelength conversion film 1 according to the first embodiment of the present invention will be described below with reference to FIG.

  First, an adhesive gel layer 12a made of, for example, a resin sheet having an acrylic pressure-sensitive adhesive is attached as a first adhesive layer on the support substrate 11 made of, for example, a transparent polyimide resin film.

  Next, a mask in which only a region slightly smaller than the first adhesive gel layer 12a is opened and subjected to fluorine processing is disposed on the upper part of the first adhesive gel layer 12a. Thereafter, a phosphor comprising semiconductor fine particles having a particle diameter of 20 nm or less is applied by applying an organic solvent containing a quantum dot phosphor having an emission wavelength of 530 nm and a quantum dot phosphor having an emission wavelength of 620 nm by screen printing. Layer 13 is formed. At this time, the phosphor layer 13 made of semiconductor fine particles is in a state where the quantum dot phosphor is dispersed in an organic solvent. In the quantum dot phosphor, the core material is CdSe and the shell material is ZnS.

  Thereafter, the mask is removed and dried to evaporate the organic solvent. Thereby, the quantum dot phosphor is fixed in contact with the first adhesive gel layer 12a. At this time, the ligand constituting the outermost layer of the quantum dot phosphor is in contact with the surface of the adhesive gel layer 12a.

  Next, the phosphor layer 13 is covered with a second adhesive gel layer 12 b that is slightly larger than the area of the phosphor layer 13. As the adhesive gel layer 12b, a resin sheet having an acrylic adhesive was used.

  Next, a mask having an opening that is slightly larger than both the first adhesive gel layer 12 a and the second adhesive gel layer 12 b is disposed on the support substrate 11. Thereafter, an oxygen barrier layer 15 made of a silicon oxynitride film (SiON) is formed on the support substrate 11 so as to cover the second adhesive gel layer 12b using a sputtering apparatus. The oxygen barrier layer 15 is formed from the upper surface and the side surface of the second adhesive gel layer 12 b to the upper surface of the support substrate 11. The oxygen barrier layer 15 is formed with a film thickness of 10 nm or more.

  Then, the wavelength conversion film 1 can be produced by cutting into a predetermined size. In the case of bonding the support substrate 11 and the oxygen barrier layer 15 with the adhesive 16, for example, the adhesive 16 made of an epoxy adhesive is formed so as to cover the side surfaces of the support substrate 11 and the oxygen barrier layer 15, Then, cut into a predetermined size. In this manner, by bonding the support substrate 11 and the oxygen barrier layer 15 with the adhesive 16, it is possible to suppress peeling of the resin sheets (adhesive gel layers 12a and 12b) due to deterioration over time.

  In the wavelength conversion film 1 thus manufactured, the phosphor layer 13 made of quantum dot phosphors (semiconductor fine particles) is directly formed on the interface with the adhesive gel layers 12a and 12b. This eliminates the need for ligand replacement, which is necessary to disperse the quantum dot phosphor in the resin as in the conventional method. Thereby, lack of substitution of the ligand does not occur, and the detachment of the ligand can be suppressed. Therefore, it is possible to realize a wavelength conversion film that can suppress a decrease in light emission efficiency of the quantum dot phosphor.

(Second Embodiment)
Next, the wavelength conversion film 2 according to the second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view showing the configuration of the wavelength conversion film in the second embodiment of the present invention.

  As shown in FIG. 2, the wavelength conversion film 2 according to the present embodiment includes a phosphor layer 14 (second phosphor layer) and an adhesive gel in addition to the wavelength conversion film 1 according to the first embodiment. And a layer 12c (third resin layer). That is, in the wavelength conversion film 2, the phosphor layer 14 is formed on the phosphor layer 13, and the adhesive gel layer 12c is formed so as to cover the phosphor layer 14 and the adhesive gel layer 12b.

  The adhesive gel layer 12c is an adhesive layer made of gel like the adhesive gel layers 12a and 12b, and can be composed of, for example, an acrylic adhesive. The phosphor layer 14 is a semiconductor fine particle layer made of semiconductor fine particles, like the lower phosphor layer 13, and is composed of a quantum dot phosphor having a particle diameter of 20 nm or less. The oxygen barrier layer 15 is formed so as to cover the top and side surfaces of the uppermost adhesive gel layer 12c.

  The phosphor layer 13 in the present embodiment is different from the phosphor layer 13 in the first embodiment. That is, in the first embodiment, the phosphor layer 13 is composed of two types of quantum dot phosphors having different emission wavelengths, but in the present embodiment, the phosphor layer 13 and the phosphor layer 14 Are composed only of quantum dot phosphors each having a different emission wavelength. That is, the quantum dot phosphor (semiconductor fine particles) constituting the phosphor layer 13 and the quantum dot phosphor (semiconductor fine particles) constituting the phosphor layer 14 have different emission wavelengths.

  As described above, according to the wavelength conversion film 2 according to the second embodiment of the present invention, the phosphor layer 13 made of quantum dot phosphors (semiconductor fine particles) is directly formed at the interface between the adhesive gel layer 12a and the adhesive gel layer 12b. While being formed, a phosphor layer 14 made of quantum dot phosphor (semiconductor fine particles) is directly formed at the interface between the adhesive gel layer 12b and the adhesive gel layer 12c. That is, the ligand constituting the outermost layer of the quantum dot phosphor in the phosphor layers 13 and 14 is in contact with the surfaces of the adhesive gel layers 12a to 12c. Thereby, since it is not necessary to perform ligand substitution, insufficient substitution of the ligand can be eliminated, and the detachment of the ligand can also be suppressed. Therefore, it is possible to realize a wavelength conversion film that can suppress a decrease in light emission efficiency of the quantum dot phosphor.

  Further, according to the present embodiment, quantum dot phosphors having different emission wavelengths are divided into the phosphor layer 13 and the phosphor layer 14 for each emission wavelength. With this configuration, it is possible to realize a wavelength conversion film in which color unevenness is suppressed as compared with a phosphor layer in which quantum dot phosphors (semiconductor fine particles) having two different emission wavelengths are mixed.

  In this case, the magnitude relationship between the emission wavelengths of the phosphor layer 13 and the phosphor layer 14 may be set so that the phosphor layer 13 has a longer wavelength than the phosphor layer 14. The layer 13 may be set to have a shorter wavelength than the phosphor layer 14. When the phosphor layer 13 is set to have a longer wavelength than the phosphor layer 14 as in the former, high light emission efficiency can be expected because of less light reabsorption. On the other hand, when the phosphor layer 13 is set to have a shorter wavelength than the phosphor layer 14 as in the latter case, although reabsorption occurs, the Stokes loss with respect to the excitation wavelength can be reduced, so the efficiency due to heat generation. The decrease can be suppressed.

  Next, a method for manufacturing the wavelength conversion film 2 according to the second embodiment of the present invention will be described below with reference to FIG.

  First, an adhesive gel layer 12a made of, for example, a resin sheet having an acrylic pressure-sensitive adhesive is attached as a first adhesive layer on the support substrate 11 made of, for example, a transparent polyimide resin film.

  Next, a mask in which only a region slightly smaller than the first adhesive gel layer 12a is opened and subjected to fluorine processing is disposed on the upper part of the first adhesive gel layer 12a. Thereafter, by applying an organic solvent containing a quantum dot phosphor using, for example, a light emission wavelength of 620 nm, a core of CdSe, and a shell of ZnS by screen printing, the first phosphor layer has a particle size of 20 nm or less. A phosphor layer 13 made of semiconductor fine particles is formed. At this time, the phosphor layer 13 is in a state where the quantum dot phosphor is dispersed in an organic solvent.

  Thereafter, the mask is removed and dried to evaporate the organic solvent. Thereby, the quantum dot phosphor is fixed in contact with the first adhesive gel layer 12a. At this time, the ligand constituting the outermost layer of the quantum dot phosphor of the phosphor layer 13 is in contact with the surface of the adhesive gel layer 12a.

  Next, the phosphor layer 13 is covered with a second adhesive gel layer 12 b that is slightly larger than the area of the phosphor layer 13. As the adhesive gel layer 12b, a resin sheet having an acrylic adhesive was used.

  Next, a mask in which only a region slightly smaller than the second adhesive gel layer 12b is opened and subjected to fluorine processing is disposed on the upper part of the second adhesive gel layer 12b. After that, by applying an organic solvent containing a quantum dot phosphor using, for example, an emission wavelength of 530 nm, a core of CdSe, and a shell of ZnS by screen printing, a second phosphor layer having a particle size of 20 nm or less is used. A phosphor layer 14 made of semiconductor fine particles is formed. At this time, the phosphor layer 14 is in a state where the quantum dot phosphor is dispersed in the organic solvent.

  Thereafter, the mask is removed and dried to evaporate the organic solvent. Accordingly, the quantum dot phosphor is fixed in contact with the second adhesive gel layer 12b. At this time, the ligand constituting the outermost layer of the quantum dot phosphor of the phosphor layer 14 is in contact with the surface of the adhesive gel layer 12b.

  Next, the phosphor layer 14 is covered with a third adhesive gel layer 12 c that is slightly larger than the area of the phosphor layer 14. As the adhesive gel layer 12c, a resin sheet having an acrylic adhesive was used.

  Next, a mask having an opening that is slightly larger than any of the first to third adhesive gel layers 12 a to 12 c is disposed on the support substrate 11. Thereafter, an oxygen barrier layer 15 made of a silicon oxynitride film (SiON) is formed on the support substrate 11 so as to cover the third adhesive gel layer 12c using a sputtering apparatus. The oxygen barrier layer 15 is formed from the upper surface and side surface of the third adhesive gel layer 12 c to the upper surface of the support substrate 11. The oxygen barrier layer 15 is formed with a film thickness of 10 nm or more.

  Thereafter, the wavelength conversion film 2 can be manufactured by cutting into a predetermined size. When the support substrate 11 and the oxygen barrier layer 15 are bonded by the adhesive 16, for example, the adhesive 16 made of an epoxy adhesive is formed so as to cover the side surfaces of the support substrate 11 and the oxygen barrier layer 15, and thereafter And cut into a predetermined size. In this manner, by bonding the support substrate 11 and the oxygen barrier layer 15 with the adhesive 16, it is possible to suppress peeling of the resin sheets (adhesive gel layers 12a to 12c) due to deterioration over time.

  The wavelength conversion film 2 thus manufactured has phosphor layers 13 and 14 made of quantum dot phosphors (semiconductor fine particles) directly on the interface with the adhesive gel layers 12a and 12b and the interface with the adhesive gel layers 12b and 12c. Is formed. This eliminates the need for ligand replacement, which is necessary to disperse the quantum dot phosphor in the resin as in the conventional method. This eliminates the occurrence of insufficient ligand substitution and also suppresses ligand detachment. Therefore, it is possible to realize a wavelength conversion film that can suppress a decrease in light emission efficiency of the quantum dot phosphor. In the present embodiment, since the quantum dot phosphors constituting the phosphor layers 13 and 14 are divided into each layer for each emission wavelength, color unevenness is suppressed more than in the first embodiment. it can.

  In the present embodiment, the phosphor layer 13 is composed of a quantum dot phosphor having an emission wavelength of 620 nm, and the phosphor layer 14 is composed of a quantum dot phosphor having an emission wavelength of 530 nm. The body layer 13 may be composed of a quantum dot phosphor having an emission wavelength of 620 nm, and the phosphor layer 14 may be composed of a quantum dot phosphor having an emission wavelength of 530 nm. In this case, heat generation due to Stokes loss with respect to the excitation wavelength can be suppressed, and a decrease in light emission efficiency of the quantum dot phosphor can be further suppressed.

  Moreover, in this Embodiment, although the adhesion gel layers 12a-12c were comprised with the acrylic adhesive, the material enumerated in 1st Embodiment may be used. Similarly, the materials listed in the first embodiment may be used for the oxygen barrier layer 15 and the support substrate 11.

  Also in this embodiment, the configuration of the quantum dot phosphor may be any of a core type, a core / shell type, a quantum well type, etc., and the core and shell constituting the quantum dot phosphor. As the material, the materials listed in the first embodiment can be used.

(Third embodiment)
Next, a wavelength conversion film 3 according to a third embodiment of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view showing the configuration of the wavelength conversion film in the third embodiment of the present invention.

  As shown in FIG. 3, the wavelength conversion film 3 according to the present embodiment includes a support substrate 11, an adhesive gel layer 12a formed on the support substrate 11, and a fluorescence formed on the adhesive gel layer 12a. A body layer 13A.

  The support substrate 11 is a thin film-like transparent resin substrate, and can be formed of a resin film made of, for example, a transparent polyimide resin, as in the first embodiment. In addition, the adhesive gel layer 12a is an adhesive layer made of gel, and can be formed of, for example, an acrylic adhesive, as in the first embodiment.

  The phosphor layer 13A in the present embodiment includes a resin 13a and semiconductor fine particles 13b dispersed in the resin 13a. The semiconductor fine particles 13b are, for example, quantum dot phosphors having a particle size of 20 nm or less. In the present embodiment, the resin 13a or quantum dot is formed so that the polarity of the ligand constituting the outermost layer of the quantum dot phosphor, that is, the value of the dipole moment and the value of the dipole moment of the resin 13a are the same. The ligand of the phosphor is adjusted.

  Further, as in the first embodiment, the adhesive gel layer 12b is formed so as to cover the adhesive gel layer 12a and the phosphor layer 13A. Further, an oxygen barrier layer 15 made of a silicon oxide film is formed so as to cover the top and side surfaces of the adhesive gel layer 12b, and from an epoxy adhesive so as to cover the side surface of the support substrate 11 and the side surface of the oxygen barrier layer 15. An adhesive 16 is formed.

  In the present embodiment, the ligand constituting the outermost layer of the quantum dot phosphor in the phosphor layer 13A is, for example, tri-octylphosphine oxide (TOPO) used at the time of production, or , Tri-n-octylphosphine (TOP) is used. The portion where the hydrocarbon groups of these ligands are connected is nonpolar, and the dipole moment is zero. Therefore, the resin 13a in the phosphor layer 13A may be a nonpolar resin, and for example, a resin such as transparent polystyrene, transparent polypropylene, polyolefin, polymethylpentene, polytetrafluoroethylene, and polybutadiene may be used.

  As described above, according to the wavelength conversion film 3 according to the third embodiment of the present invention, the polarity (dipole moment) of the ligand of the semiconductor fine particles 13b (quantum dot phosphor) in the phosphor layer 13A and the dipole of the resin 13a. The ligand of the resin 13a or the quantum dot phosphor is adjusted so that the moment becomes substantially the same value. As a result, since the polarity of the ligand bonded to the dangling bond of the quantum dot phosphor matches the polarity of the resin material that disperses the quantum dot phosphor, the ligand of the quantum dot phosphor is not sufficiently substituted. Or the separation of the ligand can be suppressed. Therefore, it can suppress that the luminous efficiency of quantum dot fluorescent substance falls.

  Examples of the resin used for the phosphor-containing resin in the white LED light source include a silicone resin, an acrylic resin, and an epoxy resin. These resins are materials having a dipole moment greater than zero. is there. For this reason, the dipole moment of the ligand constituting the outermost layer of the quantum dot phosphor may be the same as the polarity of the resin, that is, the dipole moment of the resin. Thereby, it is possible to suppress the separation of the ligand and the aggregation of the quantum dot phosphor caused by the difference in polarity between the ligand of the quantum dot phosphor and the resin, that is, the difference in the dipole moment.

  Next, a method for manufacturing the wavelength conversion film 3 according to the third embodiment of the present invention will be described below with reference to FIG.

  First, an adhesive gel layer 12a made of, for example, a resin sheet having an acrylic pressure-sensitive adhesive is pasted on the support substrate 11 made of, for example, a transparent polyimide resin film.

  Next, a mask in which only a region slightly smaller than the first adhesive gel layer 12a is opened and subjected to fluorine processing is disposed on the upper part of the first adhesive gel layer 12a. Thereafter, a resin 13a in which semiconductor fine particles 13b made of a quantum dot phosphor having an emission wavelength of 530 nm and semiconductor fine particles 13b made of a quantum dot phosphor having an emission wavelength of 620 nm are dispersed is applied by screen printing. Then, the phosphor layer 13A is formed. In the present embodiment, the semiconductor fine particles 13b are quantum dot phosphors having a particle size of 20 nm or less. For example, CdSe is used for the core, ZnS is used for the shell, and a nonpolar (dipole moment = 0 debye) ligand. TOPO was used. Moreover, polyolefin was used as the resin 13a.

  Thereafter, the mask is removed and dried to cure the resin 13a. Thereby, since the phosphor layer 13A is fixed in contact with the adhesive gel layer 12a, peeling from the film and the like can be suppressed.

  Next, the phosphor layer 13A is covered with a second adhesive gel layer 12b that is slightly larger than the area of the phosphor layer 13A.

  Next, a mask having an opening that is slightly larger than both of the adhesive gel layers 12 a and 12 b is disposed on the support substrate 11. Thereafter, an oxygen barrier layer 15 made of a silicon oxynitride film (SiON) is formed on the support substrate 11 so as to cover the second adhesive gel layer 12b using a sputtering apparatus. The oxygen barrier layer 15 is formed with a film thickness of 10 nm or more on the upper surface and side surfaces of the adhesive gel layer 12b.

  Thereafter, the wavelength conversion film 3 can be produced by cutting into a predetermined size. In the case of bonding the support substrate 11 and the oxygen barrier layer 15 with the adhesive 16, for example, the adhesive 16 made of an epoxy adhesive is formed so as to cover the side surfaces of the support substrate 11 and the oxygen barrier layer 15, Then, cut into a predetermined size. Thus, by peeling the resin sheet (adhesive gel layers 12a and 12b) due to deterioration over time, the support substrate 11 and the oxygen barrier layer 15 are bonded by the adhesive 16.

  In this embodiment, acrylic pressure-sensitive adhesives are used as the adhesive gel layers 12a and 12b. However, the materials listed in the first embodiment may be used. Similarly, the materials listed in the first embodiment may be used for the oxygen barrier layer 15 and the support substrate 11.

  Also in this embodiment, the configuration of the quantum dot phosphor that is the semiconductor fine particle 13b may be any of a core type, a core / shell type, a quantum well type, etc. The materials listed in the first embodiment can also be used as the materials.

  In the present embodiment, the semiconductor fine particles 13b made of a quantum dot phosphor having an emission wavelength of 530 nm and the semiconductor fine particles 13b made of a quantum dot phosphor having an emission wavelength of 620 nm are dispersed in a resin 13a to form one layer. Although the phosphor layer 13A is configured, the phosphor layer may be formed in two layers as in the second embodiment. In this case, the first phosphor layer is configured by dispersing only semiconductor fine particles made of 530 nm quantum dot phosphor in a resin, and the second phosphor layer is made only of semiconductor fine particles made of 620 nm quantum dot phosphor. Alternatively, the first phosphor layer may be formed by dispersing only semiconductor fine particles made of 620 nm quantum dot phosphors in the resin, and the second phosphor layer. Alternatively, only semiconductor fine particles made of a quantum dot phosphor of 530 nm may be dispersed in a resin.

  As described above, the configuration in the present embodiment can be applied to the first embodiment. That is, in the first embodiment, the phosphor layer is configured such that the quantum dot phosphor is contained in the resin, and the dipole moment of the ligand and the dipole moment of the resin constituting the outermost layer of the quantum dot phosphor Can be the same value.

(Fourth embodiment)
Next, a light emitting device according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a configuration of a light emitting device according to the fourth embodiment of the present invention.

  The light emitting device 20 according to the present embodiment is a light emitting device using the wavelength conversion film 1 according to the first embodiment, and as shown in FIG. 4, a package 21 having a recess (cavity), and a package The light emitting element 22 mounted in the recessed part of 21 and the wavelength conversion film 1 formed in the upper part of the package 21 are provided.

  The package 21 (LED package) is made of, for example, a white resin, and the inner surface of the recess has a reflecting surface inclined so as to reflect the light emitted from the light emitting element 22 in the light extraction direction (on the wavelength conversion film 1 side). It has become. The recesses of the package 21 are filled with a resin 23b in which the scattering material 23a is dispersed by potting. A lead frame 24 made of a conductor is embedded in the bottom surface of the recess of the package 21. A part of the lead frame 24 is exposed to the bottom surface in the recess of the package 21 and is electrically connected to the light emitting element 22 as a first electrode and a second electrode.

  The light emitting element 22 is mounted on the bottom surface of the recess of the package 21, and an LED chip can be used. Since the phosphor layer 13 of the wavelength conversion film 1 is composed of a quantum dot phosphor that emits light at 530 nm and a quantum dot phosphor that emits light at 620 nm, the light emitting element 22 is an LED chip having an emission wavelength of 380 nm to 480 nm. It is preferable to use it.

The scattering material 23a has a function of scattering light emitted from the light emitting element 22, and for example, light scattering fine particles made of white fine particles such as titanium dioxide (TiO ₂ ) can be used. Moreover, as the resin 23b, a transparent resin such as a silicone resin can be used.

  The wavelength conversion film 1 is disposed on the upper portion of the package 21 so as to cover the opening of the concave portion of the package 21, and is formed with a size corresponding to the area of the upper surface region of the package 21. The configuration of the wavelength conversion film 1 is the same as that of the first embodiment, and the phosphor layer 13 is composed of a quantum dot phosphor. The package 21 and the wavelength conversion film 1 are bonded by an adhesive 16.

  As mentioned above, according to the light-emitting device 20 which concerns on the 4th Embodiment of this invention, since the scattering material 23a and the quantum dot fluorescent substance are isolate | separated inside and outside the package 21, quantum dot fluorescent substance and the scattering material 23a are separated. The occurrence of color unevenness due to the radiation angle can be suppressed without causing problems in the dispersion state.

  That is, conventionally, a resin in which quantum dot phosphors are dispersed is potted in the recesses of the package. However, this method has a problem that color unevenness occurs depending on the radiation angle. Therefore, it has been considered to suppress the occurrence of color unevenness due to the radiation angle by mixing the scattering material with the quantum dot phosphor together with the resin. However, in this case, since the particle size of the scattering material is 10 μm or more in diameter, the particle size of the quantum dot phosphor is 20 nm or less, so that the scattering material and the quantum dot phosphor are well dispersed in the resin. There was a problem of not being. In contrast, in the present embodiment, the scattering material 23 a is dispersed in the resin 23 b in the recess of the package 21, and the quantum dot phosphor is formed on the wavelength conversion film 1 outside the package 21. Thereby, since the scattering material 23a and the quantum dot phosphor are separated, the quantum dot phosphor and the scattering material 23a having different particle sizes are not mixed in the resin 23b. Therefore, it is possible to suppress the occurrence of uneven color due to the radiation angle without causing the problem that the scattering material and the quantum dot phosphor are not well dispersed in the resin.

  Next, a method for manufacturing the light emitting device 20 according to the fourth embodiment of the present invention will be described below with reference to FIG.

First, the light emitting element 22 made of an LED having an emission wavelength of 450 nm is mounted in the concave portion of the package 21, and then potted with titanium dioxide (TiO ₂ ) dispersed as a scattering material 23 a in a resin 23 b made of a silicone resin, The recesses of the package 21 are filled with the resin 23b in which the scattering material 23a is dispersed.

  Next, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 1 in a state before being bonded with the adhesive 16 is produced by the same method as in the first embodiment.

  Next, the wavelength conversion film 1 is disposed on the upper surface of the package 21, and the wavelength conversion film 1 and the package 21 are bonded by an adhesive 16 made of an epoxy adhesive. At this time, the side surfaces of the support substrate 11 and the oxygen barrier layer 15 are also bonded by the adhesive 16. Through the above steps, the light-emitting device 20 according to this embodiment can be manufactured.

In the present embodiment, titanium dioxide is used as the scattering material 23a, but the present invention is not limited to this. Examples of the scattering material 23a include niobium oxide (NbO _x ), hafnium oxide (HfO _x ), indium oxide (In ₂ O _x ), tungsten oxide (WO _x ), tin oxide (SnOx), and zinc oxide. (ZnOx), zirconia oxide (ZrOx), magnesium oxide (MgO), antimony oxide (SbO _x ), zeolite (aluminosilicate), silver oxide (Ag ₂ O), or the like may be used. In each composition formula, all are x> 0. Further, as the scattering material 23a, a phosphor having a large particle diameter such as YAG or SiAlON may be used instead of the light-reflecting fine particles. When the phosphor is used as the scattering material 23a in this way, the wavelength conversion film 1 emits light of 530 nm and 620 nm by the quantum dot phosphor, and the package 21 has a vicinity of 550 nm by the YAG or SiAlON scattering material 23a in the resin 23b. Therefore, color reproducibility can be improved.

(Modification 1 of the fourth embodiment)
Next, a light-emitting device 20A according to Modification 1 of the fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a configuration of a light emitting device in Modification 1 of the fourth embodiment of the present invention.

  In the fourth embodiment shown in FIG. 4 described above, the package type light emitting device is configured using the wavelength conversion film 1 shown in FIG. 1, but in this modification, the wavelength conversion film 2 shown in FIG. 2 is used. Thus, a package type light emitting device is formed. That is, the light emitting device 20A according to this modification differs from the light emitting device 20 shown in FIG. 4 only in the configuration of the wavelength conversion film.

  Specifically, as illustrated in FIG. 5, the light emitting device 20 </ b> A according to the present modification includes a package 21, a light emitting element 22 mounted in a recess of the package 21, and a wavelength conversion film 2 formed on the top of the package 21. With. A recess of the package 21 is filled with a resin 23b in which a scattering material 23a is dispersed. The wavelength conversion film 2 is disposed so as to cover the opening of the concave portion of the package 21, and is formed with a size corresponding to the area corresponding to the upper surface region of the package 21. The package 21 and the wavelength conversion film 2 are bonded by an adhesive 16.

  As described above, according to the light emitting device 20A according to the present modification, the wavelength conversion film having two phosphor layers is used, and the scattering material 23a and the quantum dot phosphor are separated inside and outside the package 21, The occurrence of color unevenness due to the radiation angle can be suppressed without causing a problem in the dispersion state of the quantum dot phosphor and the scattering material 23a.

  That is, conventionally, a resin in which quantum dot phosphors are dispersed is potted in the recesses of the package. However, this method has a problem that color unevenness occurs depending on the radiation angle. Therefore, it has been considered to suppress the occurrence of color unevenness due to the radiation angle by mixing a scattering material with a resin together with the quantum dot phosphor, or forming quantum dot phosphor layers having different wavelengths. However, in this case, since the particle size of the scattering material is 10 μm or more in diameter, the particle size of the quantum dot phosphor is 20 nm or less, so that the scattering material and the quantum dot phosphor are well dispersed in the resin. In the case where two phosphor layers are formed in the resin using, for example, two types of quantum dot phosphors, there is a problem in controlling the thickness of each layer in the resin. On the other hand, in this modification, a wavelength conversion film in which phosphor layers made of quantum dot phosphors (semiconductor fine particles) having two different emission wavelengths are separately provided is formed, and the scattering material 23a and the quantum of each layer are further formed. The dot phosphor is separated. Therefore, it is possible to suppress the occurrence of uneven color due to the radiation angle without causing the problem that the scattering material and the quantum dot phosphor are not well dispersed in the resin.

  Next, a method for manufacturing the light emitting device 20A according to this modification will be described below with reference to FIG.

First, the light emitting element 22 made of an LED having an emission wavelength of 450 nm is mounted in the concave portion of the package 21, and then titanium dioxide (TiO ₂ ) as a scattering material 23 a is dispersed in the resin 23 b made of silicone resin. And filling the recesses of the package 21 with the resin 23b in which the scattering material 23a is dispersed.

  Next, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 2 in a state before being bonded with the adhesive 16 is produced by the same method as in the second embodiment.

  Next, the wavelength conversion film 2 is disposed on the upper surface of the package 21, and the wavelength conversion film 2 and the package 21 are bonded by an adhesive 16 made of an epoxy adhesive. At this time, the side surfaces of the support substrate 11 and the oxygen barrier layer 15 are also bonded by the adhesive 16. As described above, the light emitting device 20A according to the present modification can be manufactured.

In this modification, titanium dioxide is used as the scattering material 23a. However, niobium oxide (NbO _x ), hafnium oxide (HfO _x ), indium oxide (In ₂ ), as in the fourth embodiment. O _x), tungsten oxide (WOx), tin oxide _(SnO x), zinc oxide _(ZnO x), zirconium oxide _(ZrO x), magnesium oxide (MgO), antimony oxide _(SbO x), Zeolite (aluminosilicate) or silver oxide (Ag ₂ O) may be used. As in the fourth embodiment, a phosphor having a large particle size such as YAG or SiAlON may be used as the scattering material 23a. When a phosphor is used as the scattering material 23a, the wavelength conversion film 2 emits light of 620 nm by the quantum dot phosphor in the first phosphor layer 13, and by the quantum dot phosphor in the second phosphor layer 14. The package 21 emits light at 530 nm, and the package 21 emits light near 550 nm by the YAG or SiAlON scattering material 23a in the resin 23b. Therefore, color reproducibility can be improved.

(Modification 2 of the fourth embodiment)
Next, a light-emitting device 20B according to Modification 2 of the fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional view showing a configuration of a light emitting device in Modification 2 of the fourth embodiment of the present invention.

  In the fourth embodiment shown in FIG. 4 described above, the package type light emitting device is configured using the wavelength conversion film 1 shown in FIG. 1, but in this modification, the wavelength conversion film 3 shown in FIG. 3 is used. Thus, a package type light emitting device is formed. That is, the light emitting device 20B according to this modification is different from the light emitting device 20 shown in FIG. 4 only in the configuration of the wavelength conversion film.

  Specifically, as illustrated in FIG. 6, the light emitting device 20 </ b> B according to the present modification includes a package 21, a light emitting element 22 mounted in a recess of the package 21, and a wavelength conversion film 3 formed on the top of the package 21. With. A recess of the package 21 is filled with a resin 23b in which a scattering material 23a is dispersed. The wavelength conversion film 3 is disposed so as to cover the opening of the concave portion of the package 21, and is formed with a size corresponding to the upper surface area of the package 21. The package 21 and the wavelength conversion film 2 are bonded by an adhesive 16.

  As described above, according to the light emitting device 20B according to the present modification, since the scattering material 23a and the quantum dot phosphor are separated inside and outside the package 21, there is a problem in the dispersion state of the quantum dot phosphor and the scattering material 23a. The generation of color unevenness due to the radiation angle can be suppressed without causing it.

  That is, conventionally, a resin in which quantum dot phosphors are dispersed is potted in the recesses of the package. However, this method has a problem that color unevenness occurs depending on the radiation angle. Therefore, it has been considered to suppress the occurrence of color unevenness due to the radiation angle by mixing a scattering material with a resin together with the quantum dot phosphor, or forming quantum dot phosphor layers having different wavelengths. However, in this case, since the particle size of the scattering material is 10 μm or more in diameter, the particle size of the quantum dot phosphor is 20 nm or less, so that the scattering material and the quantum dot phosphor are well dispersed in the resin. In the case where two phosphor layers are formed in the resin using, for example, two types of quantum dot phosphors, there is a problem in controlling the thickness of each layer in the resin. On the other hand, in this modification, the scattering material 23 a is dispersed in the resin 23 b in the recess of the package 21, and the quantum dot phosphor is formed on the wavelength conversion film 1 outside the package 21. Thereby, since the scattering material 23a and the quantum dot phosphor are separated, the quantum dot phosphor and the scattering material 23a having different particle sizes are not mixed in the resin 23b. Therefore, it is possible to suppress the occurrence of uneven color due to the radiation angle without causing the problem that the scattering material and the quantum dot phosphor are not well dispersed in the resin.

  Next, a method for manufacturing the light emitting device 20B according to this modification will be described below with reference to FIG.

First, the light emitting element 22 made of an LED having an emission wavelength of 450 nm is mounted in the concave portion of the package 21, and then titanium dioxide (TiO ₂ ) as a scattering material 23 a is dispersed in the resin 23 b made of silicone resin. And filling the recesses of the package 21 with the resin 23b in which the scattering material 23a is dispersed.

  Next, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 3 in a state before being bonded with the adhesive 16 is produced by the same method as in the third embodiment.

  Next, the wavelength conversion film 3 is disposed on the upper surface of the package 21, and the wavelength conversion film 3 and the package 21 are bonded with an adhesive 16 made of an epoxy resin agent. At this time, the side surfaces of the support substrate 11 and the oxygen barrier layer 15 are also bonded by the adhesive 16.

In this modification, titanium dioxide is used as the scattering material 23a. However, niobium oxide (NbO _x ), hafnium oxide (HfO _x ), indium oxide (In ₂ ), as in the fourth embodiment. O _x), tungsten oxide _(WO x), tin oxide _(SnO x), zinc oxide _(ZnO x), zirconium oxide _(ZrO x), magnesium oxide (MgO), antimony oxide _(SbO x) Zeolite (aluminosilicate) or silver oxide (Ag ₂ O) may be used. As in the fourth embodiment, a phosphor having a large particle size such as YAG or SiAlON may be used as the scattering material 23a. When a phosphor is used as the scattering material 23a, the wavelength conversion film 3 emits light of 530 nm and 620 nm by the semiconductor fine particles 13b (quantum dot phosphor) in the resin 13a. In the package 21, YAG or SiAlON in the resin 23b is emitted. Since the scattering material 23a emits light near 550 nm, color reproducibility can be improved.

(Fifth embodiment)
Next, illumination devices 30, 40, and 50 according to a fifth embodiment of the present invention will be described with reference to FIGS. 7, 8A, 8B, and 9. FIG. FIG. 7 is a partially cutaway side view showing the configuration of the first lighting device according to the fifth embodiment of the present invention. 8A and 8B are a partially cutaway side view and a top view showing the configuration of the second lighting device according to the fifth embodiment of the present invention. FIG. 9 is a partially cutaway side view and top view showing the configuration of the third lighting device according to the fifth embodiment of the present invention.

  As shown in FIGS. 7-9, the 1st-3rd illuminating devices 30,40,50 in this Embodiment are light bulb-shaped LED lamps, Comprising: The light bulb cover 31 (glove) and the light bulb housing | casing 32 And a base 33, a heat radiation member 34, and an LED light source (light emitting device).

  The light bulb cover 31 is a hemispherical glass transparent cover for radiating light emitted from the LED light source to the outside of the lamp. The light bulb cover 31 is subjected to a light diffusion process such as a ground glass process in order to diffuse the light emitted from the LED light source.

  The light bulb casing 32 is a metal cylindrical heat sink (heat radiator) having two openings in the vertical direction. The light bulb casing 32 can be made of, for example, an aluminum alloy material, and the surface thereof is anodized. In addition, a lighting circuit for lighting the LED light source is housed in the bulb housing 32. The lighting circuit is composed of a rectifying diode bridge, a smoothing capacitor, etc., and converts AC power received from the base 33 into DC power and supplies it to the LED light source.

  The base 33 is a power receiving unit for receiving AC power through two contact points. The electric power received by the base 33 is input to the lighting circuit via a lead wire (not shown). For the base 33, for example, E26 type or E17 type can be used.

  The heat radiating member 34 is a heat radiating member for conducting heat generated from the LED light source to the bulb housing 32 and a light source mounting member for arranging the LED light source. The heat radiating member 34 is a disc-shaped substrate made of alumina, for example, and is attached to the opening on the light bulb cover 31 side of the light bulb casing 32.

  As shown in FIG. 7, in the first lighting device 30, one or a plurality of light emitting devices 20 shown in FIG. 4 are mounted as LED light sources on the heat dissipation member 34. The cover 31 is sealed.

  As described above, according to the configuration of the first lighting device 30, the LED light source (light emitting device 20) is mounted on the heat radiating member 34. Therefore, the quantum dot phosphor is heated by the heat generated by the light emitting element 22 (LED). It can suppress that luminous efficiency falls. In FIG. 7, instead of the light emitting device 20 shown in FIG. 4, the light emitting device 20A shown in FIG. 5 or the light emitting device 20B shown in FIG. 6 may be used as the LED light source.

  8A and 8B, in the second lighting device 40, the wavelength conversion film is separated from the package on which the light emitting element is mounted, and the wavelength conversion film is formed on the opening surface of the bulb cover 31. . Specifically, four light emitting devices 20 in a state where the wavelength conversion film 1 in FIG. 4 is not formed as LED light sources are mounted on the heat radiating member 34. Further, the wavelength conversion film 1 having the configuration shown in FIG. 1 is formed so as to cover the opening portion of the light bulb cover 31. The light bulb cover 31 and the wavelength conversion film 1 are sealed with a sealing adhesive 35.

  As described above, according to the configuration of the second lighting device 40, the package 21 on which the light emitting element 22 (LED) is mounted is mounted on the heat radiating member 34. It can suppress that the luminous efficiency of a body falls. 8A and 8B, the wavelength conversion film 2 shown in FIG. 2 or the wavelength conversion film 3 shown in FIG. 3 may be used instead of the wavelength conversion film 1 shown in FIG.

  As shown in FIG. 9, in the third lighting device 50, the wavelength conversion film is separated from the package on which the light emitting element is mounted, and the wavelength conversion film is formed on the inner surface of the bulb cover 31. Specifically, four light emitting devices 20 in a state where the wavelength conversion film 1 in FIG. 4 is not formed as LED light sources are mounted on the heat radiating member 34 as in the second lighting device 40. Further, each film in the wavelength conversion film 1 shown in FIG. 1 is laminated on the inner surface of the light bulb cover 31 according to the inner surface shape. From the inner surface of the light bulb cover 31, the adhesive gel layer 12a, the phosphor layer 13, the adhesive A gel layer 12b and an oxygen barrier layer 15 are formed. In FIG. 9, the light bulb cover 31 functions as a support substrate for the wavelength conversion film.

  As described above, according to the configuration of the third lighting device 50, color unevenness due to the radiation angle can be suppressed, and the wavelength conversion film formed on the inner surface of the bulb cover 31 is the light emitting element 22 that is a heating element. Since it is sufficiently separated from (LED) and separated, it is possible to suppress the light emission efficiency of the quantum dot phosphor from being reduced by the heat generation of the light emitting element 22. In addition, in FIG. 9, as a wavelength conversion film | membrane LED light source, instead of the component of the wavelength conversion film 1 shown in FIG. 1, the structure of the wavelength conversion film 2 shown in FIG. 3 or the component of the wavelength conversion film 2 shown in FIG. A laminated film may be formed using elements.

  In the first illumination device 30, the second illumination device 40, and the third illumination device 50, it is preferable to fill the bulb cover 31 with nitrogen and enclose the bulb cover 31 when sealing with the bulb cover 31. By filling the bulb cover 31 with nitrogen, in addition to the effects of oxygen barrier properties and water vapor barrier properties due to the oxygen barrier layer, it is possible to realize long-term reliability of the wavelength conversion film.

Moreover, in the 1st-3rd illuminating devices 30, 40, and 50, the number of the light emitting elements 22 may be one, or plural. The light bulb cover 31 is not made of frosted glass, but is made of titanium dioxide (TiO _x ), niobium oxide (NbO _x ), hafnium oxide (HfO _x ), indium oxide (In ₂ O _x ), Tungsten oxide (WO _x ), tin oxide (SnO _x ), zinc oxide (ZnO _x ), zirconia oxide (ZrO _x ), magnesium oxide (MgO), antimony oxide (SbO _x ), zeolite (aluminosilicate) Acid) or a resin made of plastic containing a scattering material made of silver oxide (Ag ₂ O). In this case, as the resin material of the light bulb cover 31, for example, an acrylic resin, an epoxy resin, a fluorine resin, a polyamide resin, a polyester resin, or a vinyl alkyl ether resin can be used.

  Next, each manufacturing method of the 1st-3rd illuminating device 30,40,50 which concerns on this Embodiment is demonstrated below with reference to FIGS.

First, as shown in FIG. 7, for the first lighting device 30, first, the light emitting device 20 is manufactured by the same method as in the fourth embodiment. Specifically, a light emitting element 22 made of an LED having a light emission wavelength of 450 nm is mounted in a recess of the package 21, and then titanium dioxide (TiO ₂ ) as a scattering material 23a is dispersed in a resin 23b made of silicone resin. 21 is potted, and the concave portion of the package 21 is filled with a resin 23b in which the scattering material 23a is dispersed. Thereafter, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 1 in a state before being bonded with the adhesive 16 is produced by the same method as in the first embodiment. Thereafter, the wavelength conversion film 3 is disposed on the upper surface of the package 21, and the wavelength conversion film 1 and the package 21 are bonded together with an adhesive 16 made of an epoxy resin agent.

  Next, the light emitting device 20 including the wavelength conversion film 1 is mounted on the heat dissipation member 34 made of alumina provided on the upper portion of the bulb housing 32, for example, one element. Thereafter, the bulb cover 31 and the bulb housing 32 are sealed with a sealing adhesive 35 made of an epoxy adhesive in a nitrogen atmosphere. Thereby, the 1st lighting device 30 is producible.

As for the second lighting device 40, as shown in FIGS. 8A and 8B, first, the light emitting element 22 made of LED having an emission wavelength of 450 nm is mounted in the recess of the package 21, and then the resin made of silicone resin. A material in which titanium dioxide (TiO ₂ ) is dispersed as a scattering material 23 a in 23 b is potted in a recess of the package 21, and a resin 23 b in which the scattering material 23 a is dispersed is filled in the recess of the package 21. Thereafter, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 1 in a state before being bonded with the adhesive 16 is produced by the same method as in the first embodiment. Next, the wavelength conversion film 1 having the configuration shown in FIG. 1 is formed in the opening of the light bulb housing 32, and then the light bulb cover 31 and the wavelength conversion film 1 are sealed with an epoxy adhesive. Glue and seal with 35. Thereby, the 2nd illuminating device 40 can be produced.

As for the third lighting device 50, as shown in FIG. 9, first, the light emitting element 22 made of LED having a light emission wavelength of 450 nm is mounted in the recess of the package 21, and then scattered in the resin 23b made of silicone resin. A material 23 a in which titanium dioxide (TiO ₂ ) is dispersed is potted in the recess of the package 21, and the recess of the package 21 is filled with a resin 23 b in which the scattering material 23 a is dispersed. Thereafter, the resin 23b is cured by heating at 160 ° C. Thereafter, the wavelength conversion film 1 is produced by the same method as in the first embodiment using the light bulb cover 31 as a support substrate. Finally, the light bulb cover 31 on which the wavelength conversion film 1 is formed and the light bulb casing 32 are bonded and sealed with a sealing adhesive 35 made of an epoxy adhesive. Thereby, the 3rd illuminating device 50 can be produced.

  In the present embodiment, when the light bulb cover 31 and the light bulb casing 32 are bonded, air may be used as the sealing gas. However, in order to ensure longer-term reliability, as described above. It is preferable to enclose nitrogen gas.

  As described above, the wavelength conversion film, the light emitting device, and the lighting device according to the present invention have been described based on the embodiment and the modification. However, the present invention is not limited to the above embodiment and the modification.

  For example, in the above embodiment, the LED is exemplified as the light emitting element 22, but a light emitting element such as a semiconductor laser, an organic EL (Electro Luminescence), or an inorganic EL may be used.

  Moreover, in said embodiment, although blue LED whose light emission wavelength is 450 nm was used as the light emitting element 22, it is not restricted to this. Further, the combination of the emission color of the light emitting element 22 and the fluorescence color of the quantum dot phosphor of the phosphor layer is not limited to the above embodiment. For example, white light may be emitted by a blue LED that emits blue light and a quantum dot phosphor that emits yellow light when excited by blue light. Alternatively, white light is emitted by an ultraviolet LED that emits ultraviolet light having a shorter wavelength than that of a blue LED and a quantum dot phosphor that is excited mainly by ultraviolet light and emits blue light, red light, and green light, respectively. You may comprise. Thereby, a light emitting device and a lighting device with high color rendering properties can be realized.

  In addition, the present invention includes various modifications made by those skilled in the art without departing from the scope of the present invention. Moreover, you may combine each component in several embodiment arbitrarily in the range which does not deviate from the meaning of invention.

  According to the present invention, it is possible to suppress a decrease in light emission efficiency of the quantum dot phosphor caused by lack of ligand substitution of the quantum dot phosphor, which is a semiconductor fine particle, and loss of the ligand due to dissolution in the resin. It is useful as a wavelength conversion film, and can be widely used in electronic devices such as light-emitting devices, illumination devices, and displays provided with the wavelength conversion film.

1, 2, 3 Wavelength conversion film 11 Support substrate 12a, 12b, 12c Adhesive gel layer 13, 13A, 14 Phosphor layer 13a, 23b, 65b Resin 13b Semiconductor fine particle 15 Oxygen barrier layer 16 Adhesive 20, 20A, 20B, 60 Light emitting device 21 Package 22 Light emitting element 23a Scattering material 30 First lighting device 31 Light bulb cover 32 Light bulb housing 33 Base 34 Heat radiation member 35 Sealing adhesive 40 Second lighting device 50 Third lighting device 65 Sealing resin 65a Quantum dot phosphor 110 Quantum dot phosphor 111 Semiconductor fine particle 112a Core 112b Shell 113 Ligand 120 Container 130 Lid 140 Toluene (medium to be dispersed)

Claims (13)

A support substrate; a first resin layer formed on the support substrate; and a first phosphor layer formed on the first resin layer;
The first resin layer is an adhesive layer made of gel,
The first phosphor layer is made of a quantum dot phosphor,
The wavelength conversion film in which the ligand constituting the outermost layer of the quantum dot phosphor is in contact with the adhesive layer. The wavelength conversion film according to claim 1, wherein an area where the first resin layer is in contact with the support substrate is larger than an area where the first resin layer is in contact with the first phosphor layer. And a second resin layer formed on the first phosphor layer,
The wavelength conversion film according to claim 1, wherein the second resin layer is an adhesive layer made of gel. The first phosphor layer includes a quantum dot phosphor having a first emission wavelength and a quantum dot phosphor having a second emission wavelength different from the first emission wavelength. 2. The wavelength conversion film according to item 1. Furthermore, an oxygen barrier layer formed to cover the second resin layer is provided,
The wavelength conversion film according to claim 4, wherein the oxygen barrier layer is made of a transparent resin containing an oxygen getter material or a transparent inorganic material. Furthermore, an adhesive layer for bonding the support substrate and the oxygen barrier layer is provided,
The wavelength conversion film according to claim 5, wherein the adhesive layer is an adhesive made of an organic polymer material having at least an oxygen barrier property or a water vapor barrier property. And a second phosphor layer formed on the second resin layer,
The second phosphor layer is made of a quantum dot phosphor,
The wavelength conversion film according to claim 3, wherein a ligand constituting the outermost layer of the quantum dot phosphor constituting the second phosphor layer is in contact with the adhesive layer constituting the second resin layer. . Furthermore, a third resin layer formed on the second phosphor layer is provided,
The wavelength conversion film according to claim 7, wherein the third resin layer is an adhesive layer made of gel. The first phosphor layer is composed of a quantum dot phosphor having a first emission wavelength,
The wavelength conversion film according to claim 7, wherein the second phosphor layer is made of a quantum dot phosphor having a second emission wavelength different from the first emission wavelength. The first phosphor layer is made of a resin containing the quantum dot phosphor,
The wavelength conversion film according to claim 1, wherein a dipole moment of a ligand constituting the outermost layer of the quantum dot phosphor and a dipole moment of the resin have the same value. A support substrate; a first resin layer formed on the support substrate; and a first phosphor layer formed on the first resin layer;
The first phosphor layer is composed of a resin and a quantum dot phosphor,
The wavelength conversion film, wherein a dipole moment of a ligand constituting the outermost layer of the quantum dot phosphor and a dipole moment of the resin are the same value. A package having a recess;
A light emitting device mounted in the recess;
The wavelength conversion film according to any one of claims 1 to 11 formed on the package,
The light emitted from the light emitting element is wavelength-converted by the wavelength conversion film. A light emitting element;
The wavelength conversion film according to any one of claims 1 to 11,
The light emitted from the light emitting element is wavelength-converted by the wavelength conversion film.

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