KR102108373B1 - Light conversion film comprising a quantum dot layer, backlight units for display devices including the light conversion film, and method of manufacturing a quantum dot dispersion - Google Patents

Abstract

The present invention provides a light conversion film which includes a first transparent support layer formed on an upper surface of a quantum dot layer and a second transparent support layer formed on a lower surface thereof and has a thickness 120 to 400 μm, a backlight unit for a display device including the light conversion film, a display device, a composition for forming a quantum dot layer, and a method for manufacturing a particle dispersion solution. The quantum dot layer comprises, with respect to 100 wt% of the quantum dot layer, 0.4 to 2.0 wt% of quantum dot particles containing 5 or more to less than 35 wt% of cadmium; 0.05 to 0.75 wt% of cadmium-free quantum dot particles; 0.1 to 10 wt% of a scattering agent; and 75 to 98 wt% of a matrix material. The film has a cadmium content of 10 to 100 ppm. Therefore, the light conversion film can exhibit excellent luminance and color reproduction characteristics.

Description

Light conversion film comprising a quantum dot layer, backlight units for display devices including the light conversion film, and method of manufacturing a quantum dot dispersion}

The present invention relates to a light conversion film comprising a quantum dot layer, a backlight unit for a display device including the light conversion film, and a method of manufacturing a quantum dot dispersion.

Cadmium is a heavy metal material, and is also the main culprit of soil, water, and air pollution.It penetrates into the human body through various foods that lead to the food chain, such as grains, vegetables, meat, and seafood, as well as contaminated drinking water. It may be inhaled and remain in the human body. As such, heavy metals that have penetrated the human body through various paths cause respiratory loss, vomiting, fatigue, and helplessness, and when it is severe, it destroys bone tissue and paralyzes the muscles, causing itaitai disease, a terrible pollution, and killing life. Moreover, heavy metals have a strong residual property, and when they accumulate in the tissues of the body, there is fear that they cause various damages without being discharged outside the body. For this reason, in the EU's Restriction of Hazardous Substances Directive (RoHS), six items of lead, cadmium, mercury, hexavalent chromium, phthalate, and bromine-based flame retardants are used in electronics or electrical equipment. It is limited. These materials are suggested to be 0.1% (1000 ppm) based on the weight of each material, and cadmium is more strictly limited to 0.01% (100 ppm).

Quantum dots (Quantun Dot, QD) are semi-nano-semiconductor nano-sized particles having a quantum confinement effect, and exhibit excellent optical and electrical properties that a general semiconducting material does not have in a bulk state. . Quantum dots can emit light when stimulated with energy such as light, and the color of emitted light varies depending on the size of the particles. When such a quantum dot is utilized, a large-area high-resolution display having good color purity, excellent color reproducibility, and good video characteristics can be implemented, and thus many studies on quantum dots have been conducted.

For example, quantum dot particles based on cadmium are actually commercialized and applied as a light conversion film to a backlight unit (hereinafter referred to as BLU) of a liquid crystal display. However, among the quantum dot particles containing cadmium, the green emission quantum dot particles having a CdSe or CdS type core and having a maximum absorption wavelength of 515 nm to 535 nm typically include cadmium at 35 to 55%, and the particle size is relatively large and maximum The red emitting quantum dot particles having an absorption wavelength of 620 nm to 640 nm contain cadmium at 55 to 80%. When the cadmium content contained in the quantum dot is as high as described above, it is impossible to secure color purity and color reproducibility in the photo-conversion film for display by adjusting the cadmium content to an allowable range.

In order to solve the above problems, US20170250322A1 describes a method of securing a relatively small amount of cadmium quantum dot particles by coating a thick shell on a nanostructure having a core of CdSe. However, when a thick shell is formed, optical density decreases, quantum efficiency decreases, and particle size distribution of the quantum dots increases, resulting in relatively large full width at half-maxium (FWHM), so color purity and color reproducibility are low. Losing has a problem.

Indium phosphite (hereinafter referred to as InP) -based quantum dot particles, which have undergone many studies in recent years, are attracting attention due to their eco-friendly properties. However, the InP-based quantum dot particles have a half-width of 35 to 45 nm and a quantum efficiency of 70 to 85%, and CdSe or CdS-based quantum dot particles have a significantly reduced property compared to a half-width of 20 to 30 nm and a quantum efficiency of 85 to 95%, Moisture and oxygen are also vulnerable, so there is a limitation that it cannot be applied to a display, especially a light conversion film for a backlight unit of a liquid crystal display.

US Patent Publication No. US20170250322A1

The present invention has been devised to solve the above problems of the prior art,

It is an object of the present invention to provide a photoconversion film having a cadmium content of 100 ppm or less while exhibiting excellent luminance and color reproduction characteristics while securing the maximum advantage of quantum dot particles containing cadmium.

In addition, an object of the present invention is to provide a backlight unit and a display device for a display device having safety and excellent luminance and color reproduction characteristics by including the light conversion film.

In addition, an object of the present invention is to provide an efficient method for producing quantum dot particles and quantum dot particle dispersions containing cadmium used in the photoconversion film.

The present invention

A light conversion film having a thickness of 120 to 400μm, including a first transparent support layer formed on the upper surface of the quantum dot layer and a second transparent support layer formed on the lower surface,

The quantum dot layer, based on the total weight of the quantum dot layer, the quantum dot particles containing cadmium in an amount of 5 to less than 35% by weight 0.4 to 2.0% by weight; 0.05 to 0.75% by weight of quantum dot particles not containing cadmium; 0.1 to 10% by weight of a scattering agent; And 75 to 98% by weight of the matrix material.

It provides a photoconversion film having a cadmium content of 10 to 100 ppm of the film.

In addition, the present invention,

It provides a backlight unit for a display device including the light conversion film.

In addition, the present invention,

It provides a display device including the backlight unit.

In addition, the present invention

(a) 0.4 to 2% by weight of cadmium-containing quantum dot particles having a cadmium (Cd) content of 5 to less than 35% by weight;

(b) 0.05 to 0.75% by weight of cadmium-free quantum dot particles;

(c) 75 to 98% by weight of the matrix material; And

(d) 0.1 to 10% by weight of a scattering agent; containing

Provided is a composition for forming a quantum dot layer.

In addition, the present invention

(a) 0.1 to 4.5 moles of a cation precursor containing at least one selected from a group II element and a group III element that does not contain cadmium (Cd), and V with respect to 1 mole of a cation precursor containing cadmium (Cd), and V Reacting 0.5 to 6.0 moles of an anionic precursor comprising at least one member selected from group elements and group VI elements;

(b) separating and drying the particles produced in step (a) to produce quantum dot particles having a cadmium content of 5 to 35% by weight; And

(c) dispersing the quantum dot particles having a cadmium content of 5 to 35% by weight in a concentration of 1 to 20% by weight in a compound containing a solvent or a double bond;

It provides a method for producing a quantum dot particle dispersion comprising a.

The light conversion film of the present invention secures the advantage of quantum dot particles containing cadmium to the maximum, while exhibiting excellent luminance and color reproduction characteristics, and provides an effect of substantially controlling the cadmium content to 100 ppm or less.

In addition, the present invention provides a backlight unit and a display device for a display device having safety and excellent luminance and color reproduction characteristics by including the light conversion film.

In addition, the present invention provides an efficient method for producing quantum dot particles and quantum dot particle dispersions containing cadmium used in the photoconversion film.

1 is a diagram schematically showing the structure of a liquid crystal display device,
2 is a diagram schematically showing an embodiment of the light conversion film of the present invention.

The present invention

A light conversion film having a thickness of 120 to 400μm, including a first transparent support layer formed on the upper surface of the quantum dot layer and a second transparent support layer formed on the lower surface,

The quantum dot layer, based on the total weight of the quantum dot layer, the quantum dot particles containing cadmium in an amount of 5 to less than 35% by weight 0.4 to 2.0% by weight; 0.05 to 0.75% by weight of quantum dot particles not containing cadmium; 0.1 to 10% by weight of a scattering agent; And 75 to 98% by weight of the matrix material.

The film relates to a photoconversion film having a cadmium content of 10 to 100 ppm, more preferably 10 to 80 ppm, and even more preferably 10 to 60 ppm.

In the quantum dot particles containing the cadmium more than 5 to less than 35% by weight, when the cadmium content is less than 5% by weight, it is difficult to produce quantum dot particles exhibiting sufficient color reproducibility and color purity, cadmium content when more than 35% by weight This increases, which causes environmental problems, which is undesirable. The cadmium content is more preferably 10 to 30% by weight.

The quantum dot particles containing the cadmium more than 5 to less than 35% by weight has a maximum absorption wavelength of 525 to 540nm, the quantum dot particles not containing the cadmium has a maximum absorption wavelength of 625 to 640nm. When the quantum dot layer includes the quantum dot particles having the wavelength as described above, while minimizing the cadmium content, it is possible to obtain a green light conversion film having a high color reproducibility and color purity.

It is preferable that the quantum dot particles containing the cadmium in an amount of 5 to 35% by weight have a half width of 20 to 30 nm. When the half-value width of the quantum dot particles is less than 20 nm, there is an advantage in terms of color reproducibility and color purity, but it is technically difficult and it is preferable in that it is difficult to manufacture and the yield is reduced and the amount of waste solvent is rapidly increased to reduce economic efficiency. If not, if it exceeds 30nm, color reproduction and color purity may be lowered.

Further, it is preferable that the quantum dot particles not containing cadmium have a half-value width of 35 to 50 nm. If the half-value width of the quantum dot particles is less than 35nm, there is an advantage in terms of color reproducibility and color purity, but it is technically difficult to manufacture and it is preferable in that it is difficult to manufacture and the yield is reduced and the amount of waste solvent generated is rapidly increased to reduce economic efficiency. If not, if it exceeds 50nm may cause a problem that the color reproducibility and color purity is lowered.

The quantum dot particles containing the cadmium more than 5 to less than 35% by weight is characterized by green light emission, it is preferable that the average particle diameter is 2 to 4 nm. If the average particle diameter is outside the above range, it is not characterized by green light emission.

The cadmium-free quantum dot particles feature red light emission, and preferably have an average particle diameter of 5 to 7 nm. If the average particle diameter is outside the above range, red light emission is not characterized.

The quantum dot particles containing 5 to 35% by weight of the cadmium is based on 1 mol of cadmium, 0.1 to 4.5 mol, more preferably 0.2 or more selected from group II elements and group III elements other than cadmium. To 4 moles, and 0.5 to 6.0 moles, more preferably 1.0 to 5.0 moles, at least one selected from group V elements and group VI elements.

If at least one selected from a group II element and a group III element other than cadmium is less than the above-mentioned range, the cadmium content may increase, causing environmental problems, and when it exceeds the above range, the color reproduction rate of the quantum dot particles and The color purity cannot be guaranteed, and the quantum yield may be low.

When one or more selected from the group V element and the group VI element is included in the above-mentioned range, the storage stability of the quantum dot particles decreases, and there is a disadvantage that the quantum efficiency decreases over time, and exceeds the above-described range If the stability is guaranteed, the initial quantum efficiency decreases, and a half width increase may occur.

One or more selected from Group II elements and Group III elements other than the cadmium may be selected from the group consisting of zinc (Zn), mercury (Hg), indium (In), magnesium (Mg), and aluminum (Al). Among them, zinc (Zn) can be preferably used.

At least one selected from the group V elements and group VI elements is selected from the group consisting of phosphorus (P), arsenic (As), vaginal (N), sulfur (S), selenium (Se) and tellurium (Te). It may be selected, and among these, it may be preferable to be selected from sulfur (S) and selenium (Se).

The quantum dot particles that do not contain cadmium contained in the quantum dot layer are selected from group V elements and group VI elements based on one or more moles selected from group II elements and group III elements excluding cadmium (Cd). Species 0.2 to 4.0 moles.

When one or more selected from the group V element and the group VI element is included in the above-mentioned range, the storage stability of the quantum dot particles decreases, and there is a disadvantage that the quantum efficiency decreases over time, and exceeds the above-described range In this case, stability is guaranteed, but a problem may arise that initial quantum efficiency decreases and half width increases.

One or more selected from group II elements and group III elements other than the cadmium (Cd) may be selected from zinc (Zn) and indium (In), and one or more selected from the group V elements and group VI elements Silver may be selected from sulfur (S), selenium (Se), tellurium (Te) and phosphorus (P).

Particularly, one or more selected from group II elements and group III elements other than the cadmium (Cd) is indium (In), and one or more selected from group V elements and group VI elements is phosphorus (P). It can be preferably used.

The quantum dot layer may have a cadmium content of 400 to 3000 ppm, more preferably 500 to 2600 ppm.

The quantum dot layer may have a thickness of 20 to 100 μm, preferably 40 to 80 μm. When the thickness of the quantum dot layer is less than the above range, it is difficult to express color purity and color reproducibility, and when it exceeds the above range, the cadmium content increases, there may be a decrease in luminance, and there is a problem in that economic efficiency is deteriorated.

The light conversion film includes a first transparent support layer formed on the top surface of the quantum dot layer and a second transparent support layer formed on the bottom surface, and the thicknesses of the first transparent support layer and the second transparent support layer are each independently 50 to 150 μm, more preferably May be 80 to 125 μm, more preferably 80 to 100 μm. When the thickness of the first transparent support layer and the second transparent support layer is less than the thickness, the quantum dot layer may not be sufficiently protected, so the efficiency and color purity of the quantum dots may continuously decrease, and shrinkage may occur during the curing process required to form the quantum dot layer. The appearance of the film may be deteriorated, and if it exceeds the above range, the total transmittance may decrease to decrease the quantum dot efficiency of the quantum dot light conversion film, the total thickness of the liquid crystal display may increase, and the economical efficiency may deteriorate. have.

The light conversion film may have a luminance of 700 cd / m ² or more, preferably 730 cd / m ² or more, and more preferably 750 cd / m ² or more.

The photoconversion film may have a color reproduction rate of 100% or more, preferably 110% or more, and more preferably 115% or more.

The light conversion film of the present invention

A light conversion film having a thickness of 200 to 280 μm, including a first transparent support layer formed on an upper surface of a quantum dot layer and a second transparent support layer formed on a lower surface,

The quantum dot layer has a thickness of 40 to 80μm,

The thickness of the first transparent support layer and the second transparent support layer is independently 80 to 100 μm,

The film has a cadmium content of 10 to 60 ppm,

The film may have a luminance of 760 cd / m ² or more, and a color reproduction rate of 115% or more.

The matrix material may include at least one (meth) acrylate-based compound and at least one photoinitiator.

The (meth) acrylate-based compound is selected from the group consisting of (meth) acrylated monomers, urethane (meth) acrylate oligomers, polyester (meth) acrylate oligomers, and epoxy (meth) acrylate oligomers. One or more may be used.

The matrix material may further include a polythiol-based compound.

The content of the matrix material will be described in more detail below.

In addition, the present invention

It relates to a backlight unit for a display device comprising the light conversion film.

The backlight unit for the display device may include a light guide plate, a reflective plate disposed under the light guide plate, a plurality of light emitting elements disposed on one side of the light guide plate, a light conversion film disposed on the light guide plate, and a brightness enhancement film disposed on the light conversion film. Can be.

The light emitting device may be a blue light emitting diode.

The backlight unit for the display device will be described in more detail below.

In addition, the present invention

It relates to a display device including the display unit.

The display device is not particularly limited, but may be a liquid crystal display device. The display device will be described in more detail below.

In addition, the present invention

(a) 0.4 to 2% by weight of cadmium-containing quantum dot particles having a cadmium (Cd) content of 5 to less than 35% by weight;

(b) 0.05 to 0.75% by weight of cadmium-free quantum dot particles;

(c) 75 to 98% by weight of the matrix material; And

(d) 0.1 to 10% by weight of a scattering agent; containing

It relates to a composition for forming a quantum dot layer.

The contents of the invention constituting the composition for forming the quantum dot layer can be applied in all ranges where the contents of the quantum dot layer described above can be applied.

The matrix material may preferably include at least one (meth) acrylate-based compound, a polythiol-based compound, and at least one photoinitiator.

The matrix material may preferably include 30 to 70 parts by weight of a (meth) acrylate-based compound, 10 to 50 parts by weight of a polythiol-based compound, and 1 to 6 parts by weight of one or more photoinitiators.

The composition for forming the quantum dot layer may have a cadmium content of 400 to 3000 ppm, and more preferably 500 to 2,600 ppm.

The (meth) acrylate-based compounds include isobornyl (meth) acrylate, ethylhexyl (meth) acrylate, lauryl (meth) acrylate, octyldecyl (meth) acrylate, isooctyl (meth) acrylate, At least one member selected from the group consisting of trimethylcyclohexyl (meth) acrylate, isodecyl (meth) acrylate, stearic (meth) acrylate, and tricyclodecane dimethanol di (meth) acrylate may be used. Can be.

The (a) cadmium (Cd) content is more than 5 to less than 35% by weight contained quantum dot particles are green light-emitting particles, the maximum absorption wavelength is 525 to 540nm, the half-width is 20 to 30nm, the quantum yield is 90% To 99%, the (b) cadmium-free quantum dot particles are red light-emitting particles, the maximum absorption wavelength is 625 to 640 nm, the half width is 35 to 50 nm, and the quantum yield is more preferably 70% to 85% Can be used.

The composition for forming the quantum dot layer will be described in more detail below.

In addition, the present invention

(a) 0.1 to 4.5 moles of a cation precursor containing at least one selected from a group II element and a group III element that does not contain cadmium (Cd), and V with respect to 1 mole of a cation precursor containing cadmium (Cd), and V Reacting 0.5 to 6.0 moles of an anionic precursor comprising at least one member selected from group elements and group VI elements; And

(B) separating the particles produced in the step (a); relates to a method for producing quantum dot particles containing cadmium containing more than 5 to less than 35% by weight.

In addition, the present invention

(a) 0.1 to 4.5 moles of a cation precursor containing at least one selected from a group II element and a group III element that does not contain cadmium (Cd), and V with respect to 1 mole of a cation precursor containing cadmium (Cd), and V Reacting 0.5 to 6.0 moles of an anionic precursor comprising at least one member selected from group elements and group VI elements;

(b) separating and drying the particles produced in step (a) to produce quantum dot particles having a cadmium content of 5 to 35% by weight; And

(c) dispersing the quantum dot particles having a cadmium content of 5 to 35% by weight in a concentration of 1 to 20% by weight in a compound containing a solvent or a double bond;

It relates to a method for producing a quantum dot particle dispersion comprising a.

The cadmium content of the quantum dot particle dispersion is preferably 0.1 to 7.0% by weight.

The contents described below can be applied to the method of manufacturing the quantum dot particles and the method of manufacturing the dispersion of quantum dot particles.

The cation precursor containing cadmium (Cd) includes dimethyl cadmium, diethyl cadmium, cadmium oxide, cadmium carbonate, and cadmium acetate dihydrate. , Cadmium acetylacetonate, cadmium fluoride, c cadmium chloride, cadmium iodide, cadmium bromide, cadmium perchlorate, cadmium perchlorate, cadmium perchlorate One or more selected from the group consisting of cadmium phosphide, cadmium nitrate, cadmium sulfate, cadmium carboxylate, and cadmium oleate may be used. Can be.

The precursor containing at least one selected from a group II element and a group III element not containing cadmium (Cd) may be added to the reaction at 0.1 to 4.5 moles, preferably 0.2 to 4.0 moles. If the amount of the cation precursor containing at least one selected from a group II element and a group III element that does not contain the cadmium (Cd) is less than the above-described range, the cadmium content becomes high, which may cause environmental problems. When the range is exceeded, the color reproducibility and color purity of the quantum dot particles cannot be guaranteed, and the quantum yield may be lowered.

The anionic precursor containing at least one selected from the group V elements and group VI elements may be added to the reaction at 0.5 to 6.0 mol, preferably 1.0 to 4.0 mol. When an anionic precursor containing at least one selected from the group V element and the group VI element is added below the above-described content, the storage stability of the quantum dot particles decreases, and a problem that the quantum efficiency decreases over time may occur. In addition, when added in excess of the above-mentioned content, stability is guaranteed, but a problem may arise that initial quantum efficiency decreases and half width increases.

The manufacturing method will be described in detail below.

<Display device>

Hereinafter, a liquid crystal display device will be described as an example.

1 is a diagram schematically showing the structure of a liquid crystal display device 1. The liquid crystal display device 1 includes a liquid crystal display panel 100, a pair of polarizing films 11 and 12 disposed one above and below the liquid crystal display panel 100, and a backlight unit 200.

The liquid crystal display panel 100 includes a lower display panel 13 and an upper display panel 14 and a liquid crystal layer 10 sandwiched between the two display panels 13 and 14. The lower display panel 13 may include a transparent substrate, a thin film transistor formed on a substrate through a thin film process, and switching voltage application to the pixel electrode, and a pixel electrode connected to the thin film transistor. The upper display panel 14 may include a transparent substrate, a light blocking layer and a color filter formed on the transparent substrate, a flattening film formed to cover the light blocking layer and the color filter, a common electrode formed to cover the flattening film, and the like. . The pixel electrode is formed at a position corresponding to each color filter.

The backlight unit 200 includes a light emitting device that emits blue light or ultraviolet light and a light conversion layer that converts blue light or ultraviolet light to white light, including quantum dots. The backlight unit 200 serves as a light source that supplies light to the liquid crystal display device.

The light supplied from the backlight unit 200 is linearly polarized by the lower polarizing film 11, and the phase of the linearly polarized light is selectively changed while passing through the liquid crystal layer 10. Light passing through the liquid crystal layer 10 passes through the color filter and is filtered with red, green, and blue light to reach the upper polarizing film 12, and the upper polarized light according to the degree of phase change in the liquid crystal layer 10 The amount of light passing through the film 12 varies. The amount of light passing through the upper polarizing film 12 can be controlled by adjusting the voltage applied to each pixel electrode, and thus independently controlling the amount of light of each of red, green and blue light passing through the upper polarizing film 12. Can be. The liquid crystal display device can display a color image through this process. At this time, the color gamut displayed by the liquid crystal display device is determined according to the color purity of the red light, green light, and blue light components of the white light supplied from the backlight unit 200. That is, since red light, green light, and blue light are extracted and used for display by filtering the white light supplied from the backlight unit 200 with the color filter, red light, green light, and blue light included in the white light supplied from the backlight unit 200 are included. The high color purity allows a variety of colors that can be displayed by the liquid crystal display device, so that a wide color gamut can be displayed.

The white light supplied from the backlight unit 200 includes a red light component, a green light component, and a blue light component. The color coordinates corresponding to each color component are extracted by passing the white light supplied from the backlight unit 200 through the red filter to extract the red component, passing the green filter to extract the green component, and passing the blue filter to extract the blue component. By drawing a triangle with the image positions as each vertex, the triangular color area defined above can be obtained. When the spectrum is measured while the liquid crystal display device is configured by combining the backlight unit 200 with the liquid crystal display panel 100, measurement can be performed using a color filter formed on the liquid crystal display panel 100.

The red spectrum of the liquid crystal display device is turned on and the remaining pixels are turned off to measure the red spectrum, the green pixels are turned on and the remaining pixels are turned off to measure the green spectrum, and only the blue pixels are turned on to measure the remaining pixels. A blue spectrum can be obtained. Alternatively, the spectrum of the white light emitted from the backlight unit 200 may be measured using a spectrometer, and the position on the color coordinate of each color component may be calculated using the peak wavelength and half-width of the measured spectrum. Here, since the blue light component is light emitted by the blue light emitting diode in general, it is determined according to the characteristics of the blue light emitting diode and there is little room for change. Therefore, there is an advantage that only the characteristics of the red light component and the green light component may be considered.

The backlight unit 200 includes a light guide plate 22, a reflector 20 disposed under the light guide plate 22, a light emitting element 21 disposed on one side of the light guide plate 22, and a light guide plate 22 disposed on the light guide plate 22. Light conversion film 23 may be included. In addition, a luminance enhancement film 24 and a reflective polarizing plate 25 may be included on the light conversion film 23. The light guide plate 22 serves to convert light (point light source) generated from the light emitting element 21 to the front surface of the backlight and convert it to a surface light source. The light guide plate 22 may selectively use a general type light guide plate having the same thickness or an inclination that gradually decreases in thickness in the opposite direction from the vicinity of the light emitting element 21, and the light guide plate 22 has a high transmittance and excellent heat resistance. For example, poly methyl methacrylate resin (PMMA), polycarbonate resin (PC), polyethylene telephthalate resin (PET), and the like may be selected and manufactured by melt extrusion. In addition, the reflective plate 20 disposed under the light guide plate 22 may serve to reflect light that deviates to the lower portion of the backlight from among the light emitted from the light emitting element 21 and raise it upward, thereby reducing light loss. As for the light emitting element 21, it is preferable to use a blue light emitting diode as mentioned above, and while the blue light emitting diode passes through the light conversion film 23, some of the light is converted into a red light component and a green light component. , Has the advantage of increasing the color purity. Light passing through the light conversion film 23 may pass through the luminance enhancement film 24 to increase luminance. The luminance-enhancing film 24 serves to collect light by forming a cured layer having a high refractive index in a prism shape on a transparent support layer, and may increase energy efficiency.

<Photo conversion film>

2 is a diagram schematically showing an embodiment of the light conversion film 23 of the present invention. In the present invention, the photo-conversion film 23 may be, for example, a quantum dot layer formed in the first transparent support layer 30 and the second transparent support layer 31, but is not limited thereto. The quantum dot layer 40 includes a matrix material 40 that is a curable material, quantum dot particles 41 containing 5 to less than 35 wt% cadmium, quantum dot particles 42 containing no cadmium, and a scattering agent 43. It is characterized by being prepared by curing a material composed of a mixture. The total thickness of the light conversion film 23 may be determined according to the thickness of the first transparent support layer, the second transparent support layer, and the quantum dot layer. It may be preferably 120 to 400 μm, more preferably 150 to 350 μm. If the thickness exceeds the above range, the thickness of the backlight unit may be limited, resulting in limitations in design design, and the overall brightness may be lowered from the transmittance. If it is less than the above range, durability may be deteriorated and the light conversion role may be difficult to maintain continuously. Deformation may occur due to heat generated in the backlight unit, and wrinkles may be recognized or distortion of the display screen may occur. Hereinafter, the components of the light conversion film of the present invention will be described.

(1) First transparent support layer and second transparent support layer

High transparency is required as the first transparent support layer and the second transparent support layer, and a film-shaped substrate having excellent heat resistance is used. The film-form substrate may include, for example, polyesters such as poly (meth) acrylate, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), and polyarylate; Polycarbonate, polyvinyl chloride, polyethylene, polypropylene, polystyrene, aliphatic or aromatic polyamides (e.g. nylon, aramid, etc.), polyetheretherketone, polysulfone, polyethersulfone, polyimide, polyamideimide, polyetherimide , A film containing a resin such as cyclic olefin polymer (COP), polyvinylidene chloride, but is not limited thereto.

In addition, as the first transparent support layer and the second transparent support layer, a film-type substrate having separate surface treatments may be used. Since nano-sized quantum dots are susceptible to external factors such as moisture or oxygen, they have a short lifespan, and passivation of the quantum dots surface to ensure the efficiency and color purity of the quantum dots when the quantum dot layer is applied to a light emitting diode or a quantum dot light conversion film It is important to keep the layer. Therefore, in addition to the first transparent support layer and the second transparent support layer, a barrier film (coating) for protecting the quantum dots of the quantum dot layer from the external environment (eg, moisture or oxygen) may be further formed. The barrier film (coating) may be, for example, a deposited metal oxide layer formed by sputtering or the like.

(2) quantum dot layer

In the present invention, the quantum dot layer, for example, after coating the composition for forming the quantum dot layer on at least one surface of the first transparent support layer or the second transparent support layer, and after laminating the first transparent support layer or the second transparent support layer, It may be prepared by curing by heat or ultraviolet rays, the composition for forming the quantum dot layer may include (A) to (D).

(A) Quantum dot particles containing at least 5 to less than 35% by weight of cadmium

(B) Cadmium-free quantum dot particles

(C) matrix material

(D) a scattering agent having a particle size of 0.01 to 10 μm

The composition for forming the quantum dot layer may be prepared by uniformly dispersing through a known mixing process. Mixing the compounds of (A) to (D) in a dispersion equipment equipped with an ITT (Intensive Type with Teeth) Dispersion Blade at a stirring speed of 100 to 1000 rpm, using a filter of 5 microns or less, preferably a filter of Teflon material To remove the macroparticles.

In order to minimize the dispersion of particles and the amount of macroparticles in the composition for forming a quantum dot layer, a dispersant may be additionally added. Dispersants are commercially available dispersants, such as DisperBYK-111, DisperBYK-110, DisperBYK-161, DisperBYK-162, DisperBYK-170, DisperBYK-181, DisperBYK-2000, DisperBYK-2009, DisperBYK-2200, Evonik WET-250, WET-260, WET-270, WET-280 from BASF, Efka® PU 4010, Efka® PU 4015, Efka® PU 4046, Efka® PU 4050, Efka® PU 4055, Efka® PU 4063, Efka ® PU 4080, Efka® PX 4300, Efka® PX 4330, Efka® PX 4350, Efka® PX 4700 can be purchased and used in the group.

The quantum dot particles containing (A) cadmium used in the composition for forming the quantum dot layer in an amount of 5 to less than 35% by weight and (B) quantum dot particles not containing cadmium are 1 to 1 in the compound containing a solvent or a double bond. It is preferable to use by dispersing at 20% by weight. It is preferable that the quantum dot particles are obtained by a method of purification through precipitation using a non-solvent. However, if the particles are stored in a dry state, there is a problem in that the stability is lowered and the quantum yield is lowered. When the dried quantum dots are directly added to the composition for forming the quantum dot layer, quantum dot particles may be aggregated, so desired quantum yield or half width Since it is difficult to secure the problem, a problem arises when the amount of quantum dot particles is increased. In order to solve this problem, the present invention proposes that the dried quantum dot particles are dispersed in a solvent or a compound containing a double bond in an amount of 1 to 20% by weight and applied to the composition for storage and the quantum dot layer formation. Quantum dot particles used in the present invention may contain a saturated or unsaturated aliphatic compound containing an aliphatic alkyl on the surface (the alkyl is a straight chain or branched chain having the number of carbon atoms shown below), and a hydrophobic solvent to disperse it Or it is preferable to disperse in a compound containing a hydrophobic double bond. The hydrophobic solvent is preferably an aromatic hydrocarbon solvent such as benzene, toluene or xylene, an aliphatic hydrocarbon solvent such as hexane, heptane or octane. However, when the quantum dot particles dispersed in a solvent are mixed with the composition for forming the quantum dot layer, the composition for forming the quantum dot layer is cured only after removing the solvent through a process for removing a separate solvent, for example, a high temperature and reduced pressure distillation process. After the process, problems such as adhesion, appearance, and luminance of the light conversion film do not occur.

Therefore, in order to avoid the process of removing the solvent through a high-temperature reduced pressure distillation process, a compound capable of curing with the matrix layer is preferably a compound containing a hydrophobic double bond, for example, a hydrophobic (meth) acrylate system It is preferable to disperse the quantum dot particles using a compound.

Examples of the hydrophobic (meth) acrylate-based compounds include isobornyl (meth) acrylate, ethylhexyl (meth) acrylate, lauryl (meth) acrylate, octyldecyl (meth) acrylate, and isooctyl (meth) acrylic. At least one member selected from the group consisting of acrylate, trimethylcyclohexyl (meth) acrylate, isodecyl (meth) acrylate, stearic (meth) acrylate group, tricyclodecane dimethanol di (meth) acrylate, etc. It is good to disperse in.

Through the curing process of the composition for forming the quantum dot layer may form a quantum dot layer of 20 to 100μm, preferably 40 to 80μm thickness. The thickness of the quantum dot layer can be adjusted by the amount of the composition for forming the quantum dot layer, the viscosity of the composition for forming the quantum dot layer, the lamination pressure applied when laminating the first transparent support layer or the second transparent support layer.

(2-1) quantum dot particles

Quantum dots can include cores, shells, and ligands. The quantum dots may have a size of about 10 nm or more, for example, and may have a high quantum efficiency in proportion thereto.

The core may have a substantially spherical, three-dimensional shape at the center of the quantum dot, and may include at least one cation and at least one anion. The cation may include a group II element or a group III element, for example, cadmium (Cd), zinc (Zn), and indium (In). The anion may include a group V element or a group VI element, for example, sulfur (S), selenium (Se), tellurium (Te), and / or phosphorus (P). Accordingly, the core is a binary component core containing CdSe, CdTe, CdS, ZnSe, ZnTe, InP, ZnCdS, ZnSeTe, CdSeS, ZnCdSe, ZnCdTe, etc., or a ternary core containing ZnCdSeS, ZnCdSeTe, ZnCdSeTe, ZnCdSeTe It may be a four-component core containing.

Meanwhile, the core may exhibit various colors according to its composition ratio, that is, contents of the cation and / or the anion. Accordingly, the quantum dots may have various emission colors such as blue, red, and green. Typically, the quantum dot may be a blue quantum dot or a green quantum dot.

The shell may substantially wrap the surface of the core, and may include at least one cation and at least one anion. The cation may include, for example, group II elements such as zinc (Zn) and cadmium (Cd). The anion may include, for example, a group VI element such as sulfur (S), selenium (Se), and the like. The shell may be a bicomponent shell containing ZnS, ZnSe, or the like, or a ternary shell containing ZnCdS, ZnCdSe, or the like. The shell may have a layered gradient composition. That is, the shell may have different anion content and / or different cation content from its innermost layer to its outermost layer. For example, when the shell contains zinc (Zn), cadmium (Cd) and sulfur (S), the concentration of zinc (Zn) inside the shell may be substantially lowest in its innermost layer, and substantially in its outermost layer. Can be the highest. That is, the concentration of zinc (Zn) inside the first shell may increase substantially as it moves away from the core. The shell may have a constant composition, for example, the cation content and / or the anion content uniform from the innermost layer to the outermost layer. Meanwhile, the quantum dot may further include a second shell that substantially surrounds the shell surface. In this case, the size of the quantum dots can be further increased, in particular, the bond between electrons and holes inside the core can be further protected. In addition, accordingly, the quantum dot may have a higher quantum efficiency, and may continuously maintain it.

The ligand may include, for example, an organic functional group, and chemically bind to the shell surface by the organic functional group. However, it is not limited thereto. The ligand may be introduced to the surface of the quantum dot particle by a ligand exchange reaction of a compound containing a group II element used during the shell manufacturing process, and the structure of the organic functional group of the ligand is closely related to compatibility with the matrix resin. .

(2-2) Quantum dots containing cadmium in an amount of 5 to 35% by weight

The cadmium content of 5 to less than 35% by weight of quantum dots may be prepared using at least one cationic precursor and at least one anionic precursor.

The at least one cation precursor is 0.1 to 4.5 moles of a precursor containing at least one selected from a group II element and a group III element not containing cadmium (Cd), relative to 1 mole of a cation precursor containing cadmium (Cd). , Preferably 0.2 to 4.0 mol.

When the content of the cation precursor containing at least one selected from a group II element and a group III element not containing the cadmium (Cd) is used below the above range, the cadmium content becomes high, which may cause environmental problems. When used in excess of, the color reproducibility and color purity of the quantum dot particles cannot be guaranteed, and the quantum yield may be lowered.

One or more selected from the group II elements and group III elements may be selected from zinc (Zn), mercury (Hg), indium (In), magnesium (Mg), and aluminum (Al), for example, It may be desirable to use zinc (Zn) in terms of core production and core properties.

The cation precursor containing cadmium (Cd) includes dimethyl cadmium, diethyl cadmium, cadmium oxide, cadmium carbonate, and cadmium acetate dihydrate. , Cadmium acetylacetonate, cadmium fluoride, cadmium chloride, cadmium iodide, cadmium bromide, cadmium perchlorate, cadmium perchlorate And cadmium phosphide, cadmium nitrate, cadmium sulfate, cadmium carboxylate, and cadmium oleate, and one or more of these are selected. Can be used.

The cation precursor including at least one selected from a group II element and a group III element not containing cadmium (Cd) is zinc acetate, dimethylzinc, diethyl zinc, Zinc carboxylate, zinc acetylacetonate, zinc iodide, zinc bromide, zinc chloride, zinc fluoride, zinc Zinc carbonate, zinc cyanide, zinc nitrate, zinc oxide, zinc peroxide, zinc perchlorate, zinc sulfate , Zinc oleate, mercury iodide, mercury bromide, mercury fluoride, mercury cyanide, mercury nitrate, mercury Mercury perchlorate, mercury sulfate, mercury oxide, mercury carbonate, mercury carboxylate, aluminum phosphate, aluminum acetylacetonate ), Aluminum chloride, aluminum fluoride, aluminum oxide, aluminum nitrate, aluminum sulfate , Gallium acetylacetonate, gallium chloride, gallium fluoride, gallium oxide, gallium nitrate, gallium sulfate, gallium sulfate, indium chloride ( Indium chloride, indium oxide, indium nitrate, indium sulfate, indium acetate, indium carboxylate and precursor compounds based on these precursors One or more selected from the group consisting of can be used.

At least one selected from the group II element and the group III element may prepare a cation precursor through a ligand exchange reaction to form a suitable precursor. Compounds that can be used as the ligand include, for example, monovalent alkyl (carboxylic acid) carboxylic acid compounds, and the alkyl (alkyl) is a straight or branched chain having the number of carbon atoms shown below, saturated or unsaturated. It may be an aliphatic compound. The alkyl is alkyl having 5 to 25 carbon atoms, and more preferably, it may be alkyl having 10 to 20 carbon atoms. Specifically, one or more selected from the group consisting of lauric acid, palitic acid, trityl acid, mystic acid, steric acid, pentadecyl acid, and oleic acid may be used.

The ligand exchange reaction may include, for example, mixing and dissolving the group II and / or group III elements and the alkyl carboxylic acid compound (90 to 120 ° C.); Raising the temperature to proceed with the ligand exchange reaction (140 to 170 ° C); And removing by-products generated by the ligand exchange reaction with high vacuum.

The at least one anionic precursor may be an anionic precursor including at least one selected from a group V element and a group VI element. Specifically, the group V element may be, for example, phosphorus (P), arsenic (As) or nitrogen (N), and the group VI element may be, for example, sulfur (S), selenium (Se), or And tellurium (Te).

Examples of the group V cation precursor including the group V elements include alkyl phosphine, tristrialkylsilyl phosphine (tris), trisdialkylsilyl phosphine (tris) Dialkylamino phosphine (tris), arsenic oxide, arsenic chloride, arsenic sulfate, arsenic bromide, arsenic iodide (arsenic iodide), nitric oxide (nitric oxide), nitric acid (nitric acid), ammonium nitrate (ammonium nitrate), and the like.

In addition, group VI cationic precursors containing the group VI elements include sulfur, trioctylphosphine sulfide, trialkylphosphine sulfide, and trialkenylphosphine sulfide. ), Alkylamino sulfide, alkenylamino sulfide, alkylthiol, trioctylphosphine selenide, trialkylphosphine selenide, trialkylphosphine selenide Alkenylphosphine selenide, alkylamino selenide, alkenylamino selenide, trialkylphosphine telluride, trialkenylphosphine telluride, trialkenylphosphine One or more selected from the group consisting of telluride, alkylamino telluride, alkenylamino telluride, and precursor compounds based on the precursors may be used.

The cadmium-containing quantum dot in the present invention

(a) preparing a solution comprising a core comprising at least one cationic precursor and at least one anionic precursor;

(b) preparing a compound to be used for a shell comprising particles and an organic solvent comprising at least some of the elements constituting the cation precursor and the anion precursor included in the core; And

(c) forming a quantum dot particle by injecting a solution containing the prepared core into a solution containing a compound to be used in a hot shell.

More specifically, providing a first solution comprising at least one cation precursor and a second solution comprising at least one anion precursor; Mixing the first solution and the second solution to prepare a solution comprising a core; Preparing a solution containing a compound to be used for a shell containing particles and an organic solvent comprising at least some of the elements constituting the cation precursor and the anion precursor included in the core; Gradually heating the solution containing the compound to be used in the shell to 200 to 350 ° C; And injecting the solution containing the core into the solution containing the compound to be used for the heated shell within 0.1 to 5 minutes.

Hereinafter, each step will be described in more detail.

A first solution comprising at least one cationic precursor and a second solution comprising at least one anionic precursor are prepared. At this time, the first solution is at least two or more precursors, that is, one or more cationic precursors containing cadmium (Cd) among group II elements and one selected from group II elements and group III elements not containing cadmium (Cd). And one or more precursors including a species or more.

The first solution is 0.1 to 4.5 moles of a precursor containing at least one selected from a group II element and a group III element not containing the cadmium (Cd) with respect to 1 mole of the cation precursor containing the cadmium (Cd). , Preferably it is possible to control the cadmium (Cd) content in the quantum dot particles by using 0.2 to 4.0 mol. The first solution includes two or more cation precursors, including a cation precursor containing cadmium (Cd), and the second solution may also include two or more anion precursors, but is not limited thereto. In the cation precursor, at least one selected from a group II element and a group III element not containing cadmium (Cd), the group II element may be selected from zinc (Zn) and mercury (Hg), and the group III element May be selected from indium (In), magnesium (Mg) and aluminum (Al). In particular, zinc (Zn) may be preferably used as at least one selected from group II elements and group III elements.

The anion precursor may be a precursor containing at least one member selected from group V elements and group VI elements. Specifically, the group V element may be selected from phosphorus (P), arsenic (As), and vaginal (N), and the group VI element may be selected from sulfur (S), selenium (Se), and tellurium (Te). Can be selected.

The step of preparing the first solution may include mixing a first cation precursor, a second cation precursor, and saturated / unsaturated fatty acids to form an appropriate cation precursor, followed by heating; Removing by-products by vacuum; And performing a ligand exchange reaction.

In an embodiment of the practice of the present invention, in order to prepare a first solution comprising zinc oleate and cadmium oleate, mixing zinc acetate, cadmium oxide and oleic acid, and raising the temperature to 100 to 160 ° C; Performing a ligand exchange reaction at 140 to 180 ° C; The step of removing the low molecular weight acid generated by the ligand exchange reaction with high vacuum may be performed.

Next, a solution including a core is prepared by mixing the first solution and the second solution. Specifically, the reaction of the first solution including the cation precursor and the second solution including the anion precursor may be performed at 200 to 400 ° C. More preferably, the reaction can proceed at 250 to 350 ° C. The composition ratio of the first solution and the second solution in the mixed solution may be appropriately adjusted according to the emission wavelength of the final formed quantum dot. For example, the molar ratio of the first solution and the second solution may be 1: 4 to 4: 1, but is not limited thereto.

When preparing a mixed solution containing the core, an organic solvent may be used. As the organic solvent, one capable of mixing the cation precursor of the first solution and the anion precursor of the second solution is used. Examples of the organic solvent include a primary alkylamine having 6 to 22 carbon atoms such as hexadecylamine, a secondary alkylamine having 6 to 22 carbon atoms such as dioctylamine, and a tertiary alkylamine having 6 to 40 carbon atoms such as trioctylamine, Nitrogen-containing heterocyclic compounds such as pyridine, aliphatic hydrocarbons having 6 to 40 carbon atoms such as hexadecane, octadecane, octadecene, and squalane (alkanes, alkenes, alkynes, etc.), phenyldodecane, phenyltetradecane, phenyl hexa Aromatic hydrocarbons having 6 to 30 carbon atoms such as decane, phosphine substituted with alkyl groups having 6 to 22 carbon atoms such as trioctylphosphine, phosphine oxide substituted with alkyl groups having 6 to 22 carbon atoms such as trioctylphosphine oxide, phenyl Ether, benzyl ether, etc., may be any one of aromatic ethers having 12 to 22 carbon atoms and combinations thereof, but is not limited thereto.

The organic solvent is preferably a high boiling point solvent with little steam generation and a stable high boiling point, even after heating at 200 to 350 ° C. after undergoing a water removal process by reducing the pressure at about 100 to 150 ° C.

 Through the reaction, elements of a cation precursor and an anion precursor are combined to form a quantum dot having an alloy shape. In the method of manufacturing a quantum dot of the present invention, since at least one solution contains two or more precursors, and the second solution includes at least one precursor, a core of quantum dot particles including a total of three or more elements is formed. do. Quantum dots produced by the manufacturing method of the present invention may have a single core shape including three or more elements such as Zn-Cd-S, Zn-Cd-Se, and Zn-Cd-S-Se, but are not limited thereto. . At this time, depending on the amount of the precursor containing the Cd, optical density, half width, etc. may be changed. Finally, the resultant formed from the core is cooled and purified. Specifically, the resultant quantum dot formed through the reaction step is first cooled to room temperature, and then purified and washed to obtain a core of quantum dot particles of desired purity. Purification may include the step of separating the core of the quantum dot particles by adding a nonsolvent to the resulting product. The non-solvent is a polar solvent that is mixed with the organic solvent used in the reaction but cannot disperse quantum dots, acetone, ethanol, butanol, isopropanol, ethanediol, water, tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), di Ethyl ether, formaldehyde, and the like, but is not limited thereto. Further, purification may include separating quantum dots through a method such as centrifugation, precipitation, chromatography, or distillation.

The core alloy may secure sufficient stability without including a separate shell structure, but may also include a shell structure according to a use condition or a maximum emission spectrum determined by particle size. However, it is not essential.

A manufacturing method including a stepwise synthesis process may be used to form the core primarily to manufacture a quantum dot having a core-shell structure, and then to form a shell secondarily.

For the shell formation, a cation precursor and an anion precursor, which were used to construct the core, may be used at the same time. The cation precursor is preferably a compound that does not contain a cadmium (Cd) element. When a compound containing a cadmium (Cd) element is used, the cadmium (Cd) content of the quantum dot particles increases, and environmental problems may occur. As in the case of manufacturing the core, a group II element or group III element not containing cadmium (Cd), for example, zinc (Zn), mercury (Hg), indium (In), magnesium (Mg) or aluminum (Al) It is possible to use a precursor containing, but considering the properties of the quantum dot particles or manufacturing convenience, it is preferable to use a precursor containing zinc (Zn). The cation precursor may be prepared through a ligand exchange reaction in the same manner as when the core is prepared. Mixing the cation precursor and the saturated / unsaturated fatty acid and then raising the temperature and removing the by-product by vacuum, may further include a ligand exchange reaction.

The anion precursor may be a precursor including at least one member selected from group V elements and group VI elements in the same manner as the core production. Specifically, the group V element may be selected from phosphorus (P), arsenic (As) or nitrogen (N), and the group VI element may be selected from sulfur (S), selenium (Se), and tellurium (Te). Can be.

The cation precursor and the anion precursor may be simultaneously injected to form a shell structure in an alloy form, or may be separately added to impart a gradient to the shell, but is not limited thereto.

A ligand capable of improving compatibility with a matrix material may be introduced to the prepared core or core / shell structure quantum dot particle surface through a ligand exchange reaction, but the cationic precursor used in the preparation of the core and shell may be introduced. It is not an essential process as the ligand can bind to the surface of the quantum dot particle. This may be appropriately changed through a ligand exchange reaction depending on the matrix material, or a quantum dot particle may be prepared without a separate ligand exchange process after a shell process.

Nanoparticles containing cadmium having a cadmium content of 5 to less than 35% by weight prepared by the above method are preferably CdS / ZnS, CdSe / ZnSe, CdS / ZnSe, CdS / CdSe / ZnS, CdS / CdSe / ZnSe, CdSe / ZnS / ZnSe, CdS / ZnS / ZnSe, CdS / CdSe / ZnS / ZnSe alloy, but is not limited thereto.

The quantum dot particles containing cadmium may be nanoparticles having a maximum absorption wavelength at a green wavelength of 525 to 540 nm, a maximum half width of 20 to 30 nm, and a quantum yield of 90% to 99%. The quantum dot particles in the wavelength band are relatively small in size to reduce the amount of cadmium to a minimum, and the quantum dot particles in the wavelength band require a relatively large amount to be injected into the quantum dot particles, which is a low advantage of quantum dot particles containing cadmium. It has the advantage of being able to reflect the half width and high quantum yield as much as possible.

In the present invention, the quantum dot particles containing cadmium in an amount of 5 or more and less than 35% by weight are 0.4 to 2 parts by weight, preferably 0.6 to 1.5 parts by weight, and even more Preferably it is contained in 0.7 parts by weight to 1.0 parts by weight. If it is less than the above range, the color reproducibility and color purity are lowered, and if it is more than the above range, the cadmium (Cd) content is increased, and economic efficiency may be deteriorated.

(2-3) Cadmium-free quantum dot particles

The cadmium-free quantum dot particles may include at least one cation and at least one anion. The cation may include one or more selected from group II elements and group III elements other than cadmium (Cd), and may include, for example, zinc (Zn) and / or indium (In). The anion may include at least one selected from a group V element and a group VI element, and may include, for example, sulfur (S), selenium (Se), tellurium (Te), and / or phosphorus (P). It may be prepared in a similar manner to the method for producing cadmium-containing nanoparticles having a cadmium content of 5 or more and less than 35% by weight, except for a cation precursor containing cadmium atoms. The cadmium-free quantum dot particles are preferably InP / ZnS, InP / ZnSe, and InP / ZnS / ZnSe alloy-type quantum dot particles, but are not limited thereto.

The cadmium-free quantum dot particles may be nanoparticles having a photoluminescence spectrum having a maximum emission in a red wavelength range of 625 to 640 nm, a half width of 35 to 50 nm, and a quantum yield of 75 to 85%. Since the quantum dot particles in the wavelength band have a relatively large particle size, it is not preferable to use quantum dot particles containing cadmium because the amount of cadmium is relatively increased when manufactured in cadmium form. In addition, since the quantum dot particles in the wavelength band are input to the quantum dot layer in a relatively small amount, even when using quantum dot particles that do not contain cadmium, it is possible to minimize the problems of high half width and low quantum yield, which are disadvantages of such quantum dots.

The cadmium-free quantum dot particles are 0.05 to 0.75 parts by weight, preferably 0.10 parts by weight to 0.45 parts by weight, even more preferably 0.15 parts by weight to 0.35 parts by weight based on 100 parts by weight of the composition before curing of the entire quantum dot layer It is good to include. If it is less than the above range, the color gamut and color purity are lowered, and if it is more than the above range, the hardiness may be deteriorated.

(2-4) Matrix material

The matrix material is compatible with the core-shell structured quantum dot particles and can be used irrespective of a liquid composition. The matrix material may be included in an amount of 75 to 98% by weight, preferably 88 to 98% by weight, based on the total weight of the quantum dot layer.

The liquid composition is a resin that can be cured by ultraviolet or heat, and after curing is preferably a resin that can exist as a matrix of a solid quantum dot layer. In particular, if considering processability or process convenience, an ultraviolet curing composition may be preferable. The ultraviolet curing composition may include a (meth) acrylate-based compound, a photoinitiator, and an antioxidant in the molecule. In addition, a polythiol-based compound may be used to accelerate curing and reduce curing shrinkage.

The (meth) acrylate-based compound is selected from the group consisting of (meth) acrylated monomers, urethane (meth) acrylate oligomers, polyester (meth) acrylate oligomers, and epoxy (meth) acrylate oligomers, etc. 1 The species may be mentioned, but is not limited thereto, and any (meth) acrylate-based compound conventionally used in the art may be used without limitation.

 The (meth) acrylated monomer may be prepared by ester condensation reaction of an aliphatic alcohol and (meth) acrylic acid. It may be a monofunctional, bifunctional, trifunctional, tetrafunctional, pentafunctional or hexafunctional (meth) acrylate monomer depending on the number of the aliphatic alcohols. Representative examples include (meth) acrylic acid, ethylene glycol di (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate ester, isosorbide di (meth) acrylate, tris (2-hydroxyethyl) isocyanu Late tri (meth) acrylate and di (meth) acrylate, alkyl of acrylic or methacrylic acid (e.g. isobornyl, isodecyl, isobutyl, n-butyl, t-butyl, methyl, ethyl, tetrahydrofurfuryl , Cyclohexyl, n-hexyl, iso-octyl, 2-ethylhexyl, n-lauryl, octyl or decyl) ester, hydroxy alkyl (such as 2-hydroxyethyl and hydroxypropyl) ester (meth) acrylate, Phenoxyethyl (meth) acrylate, nonylphenol ethoxylate mono (meth) acrylate, 2-(-2-ethoxyethoxy) ethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, Butylene glycol di (meth) acrylate and tri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, ethoxylated and / or propoxylated hexanediol di (meth) acrylate, ethoxylated bisphenol A diacrylate, sorbitol di (meth) acrylate, glycerol tri (meth) acrylate and its ethoxylated and / or propoxylated derivatives, bisphenol A di (meth) acrylate and its ethoxylated and / or propoxylated Derivatives, tricyclodecanedi (meth) acrylate, tricyclodecanedimethanol di (meth) acrylate, pentaerythritol di (meth) acrylate and tri (meth) acrylate and tetra (meth) acrylate and ethoxy thereof Silylated and / or propoxylated derivatives, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol Di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethoxylated and / or propoxylated neopentyl glycol di ( Meth) acrylate, hexamethylene glycol di (meth) acrylate, 4,4'-bis (2-acryloyloxyethoxy Diphenylpropane, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate and its ethoxylated and / or propoxylated derivatives, dipentaerythritol tetra (meth) acrylate and penta (meth) ) Acrylates and hexa (meth) acrylates and their ethoxylated and / or propoxylated derivatives.

Further, the urethane (meth) acrylate generally has 2 to 15 (meth) acrylate functional groups. Urethane (meth) acrylates are generally capable of reacting with at least one polyisocyanate, at least one (meth) acrylate functional group containing one or more (usually one) reactive groups capable of reacting with isocyanate groups, and optionally with isocyanate groups. Obtained from the reaction of one or more compounds containing two or more reactive groups. Reactive groups capable of reacting with isocyanate groups are generally hydroxyl groups. Examples include Miramer®PU240, Miramer®PU256, Miramer®PU2100, Miramer®UA5095, Miramer®PU3200, Miramer®PU3210, Miramer®PU330, Miramer®PU340, Miramer®PU370, Miramer®PU3410, Miramer®PU664, Miramer®SC2100 , Miramer®SC2153, Miramer®SC2152 (more than Miwon Specialty Chemicals), EBECRYL®4883, EBECRYL®9384, EBECRYL®1290, EBECRYL 220® (more than Alex company), UV-3510TL, UV3000B, UV3310B, UV-7510B, Products such as UV-7600B and UV-1700B (above Nippon Kosei) can be purchased and used selectively.

In addition, the polyester (meth) acrylate can generally be obtained from an ester reaction with one or more polyols and one or more (meth) acrylic acids. It is preferable that acrylic acid and methacrylic acid are used alone or in combination. Suitable polyester (meth) acrylates include, for example, aliphatic or aromatic polyvalent polyols that are all esterified with (meth) acrylic acid and may contain residual hydroxyl functionality in the molecule, and characterize the product. An easy and suitable way for this is to measure its hydroxyl value (mgKOH / g). Suitable are the partial or total esterification products of (meth) acrylic acid and divalent to 6-valent polyols and mixtures thereof. Further, a reaction product of the polyol and ethylene oxide and / or propylene oxide or a mixture thereof as above, or a reaction product of the polyol and lactone and lactide as described above may be used. Examples include Miramer®PS420, Miramer®PS430, Miramer®PS460, Miramer®PS610 (above Miwon Specialty Chemicals), EBECRYL®870, EBECRYL®657, EBECRYL®450, EBECRYL® 800, EBECRYL®884, EBECRYL®885 , EBECRYL®810, EBECRYL® 830 (above Alex Corporation), etc. can be purchased and used selectively.

In addition, the epoxy (meth) acrylate is generally obtained from the reaction of at least one polyepoxy compound and at least one (meth) acrylic acid. It is preferred that acrylic acid and methacrylic acid are used alone or in combination. Examples of suitable epoxy (meth) acrylate oligomers are di (meth) acrylates of diglycidyl ethers of bisphenol A and variations thereof, such as EBECRYL® 3700 or EBECRYL® 600, EBECRYL® 3701, EBECRYL®3703 , EBECRYL® 3708, EBECRYL® 3720 and EBECRYL® 3639 (above Alex), Miramer®PE210, Miramer®PE2120A, Miramer®PE250 (above Miwon Specialty Chemical).

The photoinitiator may include at least one acylphosphine oxide-based photoinitiator and at least one photoinitiator other than acylphosphine oxide-based photoinitiator. The acylphosphine oxide-based photoinitiator is bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-tribenzoyldiphenylphosphine oxide, ethyl-2,4,6 -Triethylbenzoylphenylphosphinate, and the like. In addition, photoinitiators other than the acylphosphine oxide (Acylphosphine oxide) -based, for example, α-hydroxy alkylphenone (α-hydroxyalkylphenone), α-aminoalkylphenone (α-aminoalkylphenone), benzoin ether ( Benzoineether), α, α-dialkoxyacetophenone (α, α-Dialkoxyacetophenone), phenylglyoxylate (Phenylglyoxylate), and the like. The α-hydroxy alkylphenone (α-hydroxyalkylphenone), α-aminoalkylphenone (α-aminoalkylphenone), benzoinether (Benzoineether), α, α-dialkoxyacetophenone (α, α-Dialkoxyacetophenone) Examples of the photoinitiator include 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-1- [4- (2-hydroxyethoxy), α, α-dimethoxy-α-phenylacetophenone, 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone, methylbenzoylformate, oxy -Phenyl-acetic acid 2- [2 oxo-2 phenyl-acetoxy-ethoxy] -ethyl ester and oxy-phenyl-acetic acid 2- [2-hydroxy-ethoxy] -ethyl ester mixture, etc. 1 or more types are mentioned.

The polythiol-based compound is a compound having two or more thiol functional groups, and one having one ester functional group per thiol functional group may be preferably used. As a compound having one ester functional group per thiol functional group, for example, ethylene glycol dimercaptoacetate, trimethylolpropane trimercaptoacetate, pentaerythritol tetramercaptoacetate, dipentaerythritol hexamercaptoacetate, ethylene glycol Di (3-mercaptopropionate), trimethylolpropane tri (3-mercaptopropionate), dipentaerythritol hexa (3-mercaptopropionate), ethoxylated trimethylolpropane tri (3 -Mercaptopropionate), tris [2- (3-mercaptopropionyloxy) ethyl] isocyanurate, polycaprolactone tetra (3-mercaptopropionate), pentaerythritol tetrakis (3- Mertoptobutylate), 1,4-bis (3-mercaptobutyryloxy) butane, 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2, One or more selected from the group consisting of 4,6 (1H, 3H, 5H) -trione, and trimethylol propane tris (3-mercaptobutyrate), and the like can be used.

(2-5) Scattering agent

The scattering agent is included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the quantum dot layer to scatter light entering the quantum dot layer to increase the optical path, thereby increasing the light conversion rate by increasing the chance of the light contacting the quantum dot particles It plays a role. When the amount of the scattering agent is less than the above range, the scattering is low and the light conversion rate is not sufficient. If it exceeds the above range, haze is increased and the transmittance is lowered, so that sufficient brightness cannot be secured.

The scattering particles (E) are silica (Silica), alumina (Alumina), silicon (Silicon), alumina (Alumina), titanium dioxide (TiO ₂ ), zirconia (ZrO ₂ ), barium sulfate (Barium Sulfate), zinc oxide ( ZnO), poly methacrylate (Poly (methylmethacrylate), PMMA) and benzoguanamine (Benzoguanamine) may be one or more selected from the group consisting of polymers. Also, an average particle diameter of 0.01 to 10 nanometers can be preferably used.

In the present invention,% means '% by weight' unless otherwise specified. In addition, when the unit of the concentration, such as ppm, is not specifically determined, it means the 'w / w' concentration.

Hereinafter, the present invention will be described in detail through examples. However, these examples are only presented to explain the present invention more clearly, and are not intended to limit the scope of the present invention. The scope of the invention will be defined by the technical spirit of the claims below.

Synthesis Example 1: Synthesis of green light-emitting quantum dot particles (Cd-G1) containing cadmium

4 mmol of zinc acetate, 1 mmol of cadmium oxide and 10 ml of oleic acid, 15 ml of 1-octadecene (1-octadecene, 1-ODE), which was removed under reduced pressure at 120 ° C. for 30 minutes as a solvent, was placed in a reactor, argon The mixture was reacted at 160 ° C. for 2 hours in an atmosphere, and acetic acid, a by-product generated during the reaction, was removed at a reduced pressure of 10 ⁻² torr to include cadmium oleate (Cd-OA) and zinc oleate (Zn-OA) A first solution was prepared.

Separately, 0.5 mmol of selenium, 4 mmol of sulfur and 2 mmol of trioctylphosphine were placed in a reactor and reacted at 100 ° C. for 1 hour, thereby causing trioctylphosphine selenide (Se-TOP) and tri A second solution containing octylphosphine sulfide (sulfur trioctylphosphine sulfide, S-TOP) is prepared, and then the second solution is added to the prepared first solution, and a mixture of the first solution and the second solution is prepared. It heated up to 300 degreeC and reacted for 2 hours. Then, after cooling to room temperature and sedimentation with acetone, this was centrifuged using a complex solvent containing hexane and ethanol, and IBXA (Osaka Organic Chemical Company, Isobornyl Acrylate) was used to obtain a concentration of 10% using UV-VIS equipment. ) To obtain a dispersion of quantum dot particles in an alloy form composed of selenium-sulfur-zinc-cadmium.

At this time, the content of Cd measured by ICP-MS of the quantum dot particle dispersion at a concentration of 10% in Synthesis Example 1 was 7,495 ppm (7.5% by weight of cadmium particles alone by conversion), Quantaurus-QY of Hamamatsu ( The maximum absorption wavelength measured by C11347-11) was 531.5nm, the half width (FWHM) was 25nm, and the Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 90.5%.

Synthesis Example 2: Synthesis of green light-emitting quantum dot particles (Cd-G2) containing cadmium

It was prepared in the same manner as in Synthesis Example 1 except that 2 mmol of zinc acetate and 3 mmol of cadmium oxide were used.

At this time, the content of Cd measured by ICP-MS of the 10% concentration quantum dot particle dispersion of Synthesis Example 2 was 22,761 ppm (22.8% by weight of cadmium particles alone by conversion calculation), Quantaurus-QY of Hamamatsu Corporation ( The maximum absorption wavelength measured by C11347-11) was 530.5 nm, the half width (FWHM) was 23 nm, and the Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 93.9%.

Synthesis Example 3: Synthesis of green light emitting quantum dot particles (Cd-G3) containing cadmium

It was prepared in the same manner as in Synthesis Example 1 except that 1 mmol of zinc acetate and 4 mmol of cadmium oxide were used.

At this time, the content of Cd measured by ICP-MS of the 10% concentration quantum dot particle dispersion solution of Synthesis Example 3 was 31,645 ppm (31.6% by weight of cadmium particles alone by conversion calculation), and Quantaurus-QY of Hamamatsu Co., Ltd. The maximum absorption wavelength measured by C11347-11) was 530.0 nm, the half width (FWHM) was 21 nm, and the Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 96.8%.

Commercial product 1: Green light-emitting quantum dot particles with cadmium (Cd-G4)

Commercially available cadmium type green light-emitting particles (trade name: SQD-CG100H02, manufacturer: Uniam, IBXA 10% dispersion) were obtained and used. The content of Cd measured by ICP-MS of the 10% concentration of the quantum dot particle dispersion was 49,684 ppm (49.6% by weight of the particle alone cadmium by conversion calculation), measured by Hamamatsu's Quantaurus-QY (C11347-11). The maximum absorption wavelength was 522.8nm, the half width (FWHM) was 20nm, and the Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 97.6%.

Commercially available product 2: Red emitting quantum dot particles with cadmium (Cd-R1)

Commercially available cadmium-type red light-emitting particles (trade name: SQD-CR100H01, manufacturer: Uniam, IBXA 10% dispersion) were obtained and used. The Cd content measured by ICP-MS of the 10% concentration quantum dot particle dispersion was 67,982ppm (particles alone cadmium content 67.9% by weight as calculated), measured by Hamamatsu's Quantaurus-QY (C11347-11). The maximum absorption wavelength was 620.0 nm, the half width (FWHM) was 21 nm, and the Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 97.1%.

Commercially available product 3: Non-cadmium green light emitting quantum dot particles (InP-G1)

Commercially available non-cadmium-type green light-emitting particles (trade name: SQD-FG100H03, manufacturer Uniam, IBXA 10% dispersion) were obtained and used. The Cd content measured by ICP-MS of the 10% concentration quantum dot particle dispersion was ND (Not Detect), and the maximum absorption wavelength measured by Hamamatsu's Quantaurus-QY (C11347-11) was 534.0 nm, half-width ( FWHM) was 39nm, and Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 76.5%.

Commercial product 4: Non-cadmium red luminescent quantum dot particles (InP-R1)

Commercially available non-cadmium-type red light-emitting particles (trade name: SQD-FR100H07, manufacturer Uniam, IBXA 10% dispersion) were obtained and used. The content of Cd measured by ICP-MS of the 10% concentration quantum dot particle dispersion was ND (Not Detect), and the maximum absorption wavelength measured by Hamamatsu's Quantaurus-QY (C11347-11) was 620.0 nm, half-width ( FWHM) was 40 nm, and Quantum Yield (%, internal) measured by Oscar Electronics' QE-2000 was 75.5%.

Cd-G1 Cd-G2 Cd-G3 Cd-G4 Cd-R1 InP-G1 InP-R1 Manufacturing method Synthesis Example 1 Synthesis Example 2 Synthesis Example 3 Commercial product 1 Commercial products 2 Commercial Products 3 Commercial Products 4 Cd content (%) 7.5 22.8 31.6 49.6 67.9 0.0 0.0 Maximum absorption wavelength (nm) 531.5 530.5 530.0 522.8 620.2 534.1 623.9 Half width (nm) 25 23 21 20 21 39 40 Quantum yield (%) 90.5 93.9 96.8 97.6 97.1 76.5 75.5

Preparation Example 1: Preparation of composition for quantum dot layer formation

M300 (Miwon Specialty Chemicals, trimethylpropane triacrylate) 30 parts by weight, IBXA (Osaka Yuki, isobornol acrylate) 20 parts by weight, PEMP (SC Organic Chemistry, Pentaerythritol tetrakis (3-mercapto) Propionate)) 30 parts by weight, zinc oxide (SINE Chemicals FINEX 30, average particle diameter 35 nm) 6 parts by weight, 1-hydroxy-cyclohexyl-phenyl-ketone (IGcure 184) 2 parts by weight, 2,4 , 6-Tribenzoyldiphenylphosphine oxide (I.M. Darocure TPO) 2 parts by weight, Synthesis Examples 1 to 3, commercial products 1, and commercial products 2 8 parts by weight of each green light emitting quantum dot particle dispersion, commercial products 2 and commercial products 5 2 parts by weight of each red light-emitting quantum dot particle dispersion is administered in a combination according to Table 2 below, followed by high-speed stirring at a speed of 500 rpm in a dispersion equipment equipped with an ITT (Intensive Type with Teeth) Dispersion Blade, followed by pressurization with a 1um Teflon filter. After filtering and depressurizing for 30 minutes, air bubbles in the resin were completely removed to prepare a composition for forming a quantum dot layer.

Preparation Example 2: Preparation of light conversion film containing quantum dot layer

The first transparent support layer was coated with a composition for forming each quantum dot layer prepared in Preparation Example 1 using a micro-bar, and the second transparent support layer was laminated on the second transparent support layer using a rubber roll so as not to cause bubbles to undergo ultraviolet curing. Did. At this time, the UV curing device was a Litzen UV curing machine (UVMH1001) equipped with a metal halide lamp, and the amount of light in the UVA region measured using EIT's UV Puck II was 1500 mJ. At this time, the thickness of the green light-emitting quantum dot particles and red light-emitting quantum dot particles, the first transparent support layer, the second transparent support layer and the quantum dot layer are shown in Examples and Comparative Examples in Table 2 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 First transparent mechanism
(Material / Thickness μm) PET /
100 PET /
100 PET /
100 PET /
80 PET /
50 PET /
125 PET /
100 PET /
100 PET /
50 Second transparent base (material / thickness μm) PET /
100 PET /
100 PET /
100 PET /
80 PET /
50 PET /
125 PET /
100 PET /
100 PET /
50 Green emitting particles Cd-G1 Cd-G2 Cd-G3 Cd-G3 Cd-G3 Cd-G3 InP-G1 Cd-G4 Cd-G3 Red emitting particles InP-R1 InP-R1 InP-R1 InP-R1 InP-R1 InP-R1 InP-R1 Cd-R1 InP-R1 Cadmium content of quantum dot composition
(ppm) 592 1822 2533 2533 2533 2533 0 5335 2533 Quantum dot layer thickness (μm) 80 80 80 40 80 100 80 100 125

Experimental Example: Characterization of light conversion sheet

(1) Optical characteristics

Cut the quantum dot film to fit the size of A4, attach it to the center of the backlight of the Samsung Electronics SUHD TV JS6500 model, apply power, and measure the luminance and color reproducibility at 13 points using a luminance meter (CS-2000, Minolta). The average value is shown in Table 3 below.

(2) Cadmium content

After cutting the quantum dot film to 10 Ⅹ 10cm, the cadmium content was measured using ICP-MS, and the measured cadmium content was 100 times, and the cadmium content is shown in Table 3 below.

Example
One Example
2 Example
3 Example
4 Example
5 Example
6 Comparative example
One Comparative example
2 Comparative example
3 Luminance (cd / m ² ) 761 796 776 771 821 768 650 899 862 Color gamut (%) 117.5 125.3 137.4 120.6 137.4 129.4 107.4 147.2 140.1 (ppm) 12 42 57 20 98 74 N.D 154 176

1: liquid crystal display device 10: liquid crystal
11: lower polarizing film 12: upper polarizing film
13: lower display panel 14: upper display panel
20: reflector 21: light-emitting element
22: light guide plate 23: light conversion film
24: luminance enhancement film 25: reflective polarizing plate
30: first transparent support layer 31: second transparent support layer
40: matrix material 41: cadmium-containing quantum dot particles
42: quantum dot particles not containing cadmium 43: scattering agent
100: liquid crystal display panel, 200: backlight unit

Claims (12)

(a) 0.1 to 4.5 moles of a cation precursor containing at least one selected from a group II element and a group III element that does not contain cadmium (Cd), and V with respect to 1 mole of a cation precursor containing cadmium (Cd), and V Reacting 0.5 to 6.0 moles of an anionic precursor comprising at least one member selected from group elements and group VI elements;
(b) separating and drying the particles produced in step (a) to produce quantum dot particles having a cadmium content of less than 5 to 35% by weight; And
(c) dispersing the quantum dot particles having a cadmium content of less than 5 to 35% by weight in a concentration of 1 to 20% by weight in a compound containing a solvent or a double bond;
Method of producing a quantum dot particle dispersion comprising a. According to claim 1,
Method for producing a quantum dot particle dispersion, characterized in that the cadmium content of the quantum dot particle dispersion is 0.1 to 7.0% by weight. According to claim 1,
The cation precursor containing cadmium (Cd) is dimethyl cadmium, diethyl cadmium, cadmium oxide, cadmium carbonate, cadmium acetate dihydrate, Cadmium acetylacetonate, cadmium fluoride, c admium chloride, cadmium iodide, cadmium bromide, cadmium perchlorate, cadmium perchlorate One or more selected from the group consisting of cadmium phosphide, cadmium nitrate, cadmium sulfate, cadmium carboxylate, and cadmium oleate;
The cation precursor containing at least one selected from a group II element and a group III element not containing cadmium (Cd) is zinc acetate, dimethylzinc, diethyl zinc, zinc Zinc carboxylate, zinc acetylacetonate, zinc iodide, zinc bromide, zinc chloride, zinc fluoride, zinc carbonate (zinc carbonate), zinc cyanide, zinc nitrate, zinc oxide, zinc peroxide, zinc perchlorate, zinc sulfate, And it is at least one selected from the group consisting of zinc oleate (zinc oleate);
The anionic precursors including at least one selected from the group V elements and group VI elements include alkyl phosphine, tristrialkylsilyl phosphine (tris), and trisdialkylsilyl phosphine. (dialkylsilyl phosphine)), tris (dialkylamino phosphine), arsenic oxide, arsenic chloride, arsenic sulfate, arsenic bromide ), Acetic iodide, nitric oxide, nitric acid, ammonium nitrate, sulfur, trioctylphosphine sulfide ), Trialkylphosphine sulfide, trilkenylphosphine sulfide, alkylamino sulfide, alkenylyl sulfide, alkylthiol, trioctylphosphine Sulfur trioctylphosphine selenide, trialkylphosphine selenide, trialkenylphosphine selenide, alkylamino selenide, alkenylamino selenide , Trialkylphosphine telluride, trialkenylphosphine telluride, alkylamino telluride, and alkenylamino telluride (alkenylamino telluride) method for producing a quantum dot particle dispersion, characterized in that at least one member selected from the group consisting of. According to claim 1,
The cation precursor containing cadmium (Cd) and at least one selected from group II elements and group III elements not containing cadmium (Cd) are alkylcars by ligand exchange reaction with respect to the primary precursor. Method for producing a dispersion of quantum dot particles, characterized in that it is a secondary precursor prepared by binding a carboxylic acid ligand. The method of claim 4,
The alkylcarboxylic acid ligand used in the ligand exchange reaction is a straight or branched chain, saturated or unsaturated aliphatic alkylcarboxylic acid having 5 to 25 carbon atoms. The method of claim 5,
The straight or branched chain, saturated or unsaturated aliphatic alkyl carboxylic acid having 5 to 25 carbon atoms is at least one selected from the group consisting of lauric acid, palitic acid, trityl acid, mystic acid, steric acid, pentadecyllic acid, and oleic acid. Method of producing a quantum dot particle dispersion, characterized in that. According to claim 1,
Quantum dot particles containing cadmium (Cd) content of 5 to less than 35% by weight prepared by the above manufacturing method has a maximum absorption wavelength of 525 to 540 nm, a half width of 20 to 30 nm, and a quantum yield of 90% to 99%. Method for producing a dispersion of quantum dots particles, characterized in that. According to claim 1,
The cadmium content is 5 or more to less than 35% by weight of the quantum dot particles are half-width width of 20 to 30nm method for producing a dispersion of quantum dot particles. The method of claim 8,
The method for producing a quantum dot particle dispersion liquid, characterized in that the average particle diameter of the quantum dot particles containing the cadmium 5 or more to less than 35% by weight is 2.0 to 4.0 nm. According to claim 1,
The cadmium (Cd) does not contain a group II element or a group III element selected from the group consisting of zinc (Zn), mercury (Hg), indium (In), magnesium (Mg) and aluminum (Al) Is selected from,
At least one selected from the group V elements and group VI elements is selected from the group consisting of phosphorus (P), arsenic (As), vaginal (N), sulfur (S), selenium (Se) and tellurium (Te). Method of producing a quantum dot particle dispersion, characterized in that. The method of claim 10,
Method for producing a quantum dot particle dispersion, characterized in that at least one selected from a group II element and a group III element not containing the cadmium (Cd) is zinc (Zn). The method of claim 10,
The method for producing a quantum dot particle dispersion liquid, characterized in that at least one selected from the group V element and group VI element is selected from sulfur (S) and selenium (Se).

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