KR20150041581A - Nanocrystal polymer composites and processes for preparing the same - Google Patents

Abstract

The present invention relates to a semiconductor nanocrystal composition to provide a semiconductor nanocrystal-polymer composite having excellent brightness and stability. More specifically, provided is a semiconductor nanocrystal composition comprising: a semiconductor nanocrystal; an organic additive; and a polymerizable monomer, and showing haze of more than or equal to 40% after polymerization. Also, provided is a composite manufactured from the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a nanocrystalline polymer composite,

To a nanocrystal-polymer composite and a manufacturing method thereof.

Unlike a plasma display panel (PDP) or a field emission display (FED), which is an emission type display device, a liquid crystal display device (LCD) can not emit light itself, Is a light-receiving-type display device which is incident to form an image. Accordingly, the liquid crystal display device has a backlight unit that emits light on its backside.

In a backlight unit for a liquid crystal display device, a cold cathode fluorescent lamp (CCFL) is used as a light source. However, when such a cold-cathode fluorescent lamp is used as a light source, it is difficult to ensure the uniformity of luminance as the size of the liquid crystal display device becomes larger, and the color purity decreases.

In recent years, a backlight unit using three color LEDs as a light source has been developed. A backlight using such a three-color LED as a light source can reproduce a high color purity and can be applied to a high-quality display device. However, it is disadvantageous in that it is very expensive as compared with a backlight unit using a cold cathode fluorescent lamp as a light source. In order to overcome this disadvantage, a white LED which converts light emitted from a single color LED chip into white light and emits white light is being developed.

However, although such white LEDs can secure economical efficiency, they have a problem that their color purity and color reproducibility are lower than those of the three-color LEDs. In recent years, attempts have been made to use semiconductor nanocrystals as light-converting layer materials in LEDs in order to improve color reproducibility and color purity and to secure price competitiveness.

One embodiment is directed to a semiconductor nanocrystal composition capable of providing a semiconductor nanocrystal-polymer composite having both excellent brightness and stability.

Another embodiment is for a semiconductor nanocrystal-polymer composite that is both excellent in brightness and stability.

Another embodiment relates to a backlight unit for a liquid crystal display device having both excellent brightness and stability.

In one embodiment, the semiconductor nanocrystal composition comprises a semiconductor nanocrystal; Organic additives; And at least one polymerizable substance selected from polymerizable monomers, polymerizable oligomers, and combinations thereof, wherein the haze after polymerization is 40% or more.

The polymerizable component may comprise a polymerizable monomer and a polymerizable oligomer.

The semiconductor nanocrystals may comprise Group II-VI compounds, Group III-V compounds, Group IV-VI compounds, Group IV elements or compounds, or combinations thereof.

The II-VI group compound is selected from the group consisting of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS and mixtures thereof; A trivalent element selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, Small compounds; And a Group III-V compound selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, , GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb and mixtures thereof; A trivalent compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb and mixtures thereof; And a silicate compound selected from the group consisting of GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and mixtures thereof. And the IV-VI group compound is selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; A triple compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; And a silane compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof. The Group IV element or compound may be selected from the group consisting of Si, Ge, and combinations thereof matter; And these elemental compounds selected from the group consisting of SiC, SiGe, and mixtures thereof.

The semiconductor nanocrystals may have a core shell structure.

The semiconductor nanocrystals may have a quantum efficiency of 50% or more.

The semiconductor nanocrystals may have a half-width of 45 nm or less.

The semiconductor nanocrystals may have a surface organic content of less than 35 wt% based on the total weight of the semiconductor nanocrystals, including ligand compounds, solvents, or combinations thereof.

The semiconductor nanocrystals may be 20 wt% or less based on the total weight of the polymerizable component.

The organic additive may be an amine having at least one C8 to C30 alkyl or alkenyl group, a primary phosphine having at least one C8 to C30 alkyl or alkenyl group, a phosphor having at least one C8 to C30 alkyl or alkenyl group, Pin oxide, or a combination thereof.

The organic additive may be included in an amount of about 0.05 wt% to about 10 wt% based on the total weight of the polymerizable component.

The polymerizable monomer and the polymerizable oligomer may be a mixture of a first monomer having at least two thiol (SH) groups at the terminals and a second monomer having at least two carbon-carbon unsaturated bonds at the ends, an acrylate monomer, Based oligomer, a methacrylate-based monomer, a methacrylate-based oligomer, a urethane acrylate-based monomer, a urethane acrylate-based oligomer, an epoxy-based monomer, an epoxy-based oligomer, a silicon-based monomer or a silicone-based oligomer.

The first monomer having at least two thiol (SH) groups at the terminal may be represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

R ¹ is hydrogen; A substituted or unsubstituted C1 to C30 linear or branched alkyl group; A substituted or unsubstituted C6 to C30 aryl group; A substituted or unsubstituted C3 to C30 heteroaryl group; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted C3 to C30 heterocycloalkyl group; A substituted or unsubstituted C2 to C30 alkenyl group; A substituted or unsubstituted C2 to C30 alkynyl group; A substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring; A substituted or unsubstituted C3 to C30 heterocycloalkyl group having a double bond or a triple bond in the ring; A C3 to C30 alicyclic organic group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups; A C3 to C30 heterocycloalkyl group substituted with C2 to C30 alkenyl group or C2 to C30 alkynyl group; A hydroxy group; NH ₂ ; A substituted or unsubstituted C1 to C30 amine group (-NRR ', wherein R and R' are, independently of each other, hydrogen or a C1 to C30 linear or branched alkyl group); Isocyanate group; An isocyanurate group; (Meth) acrylate groups; halogen; -ROR 'wherein R is a substituted or unsubstituted C1 to C20 alkylene group and R' is hydrogen or a C1 to C20 linear or branched alkyl group; Acyl halide (-RC (= O) X wherein R is a substituted or unsubstituted alkylene group and X is halogen; -C (= O) OR 'wherein R' is hydrogen or a C1 to C20 linear or branched alkyl group; -CN; Or -C (= O) ONRR ', wherein R and R' are, independently from each other, hydrogen or a C1 to C20 linear or branched alkyl group,

L ₁ represents a single bond, a carbon atom, a substituted or unsubstituted C1 to C30 alkylene group, a substituted or unsubstituted C6 to C30 cycloalkylene group, a substituted or unsubstituted C6 to C30 cycloalkenylene group, a substituted Or an unsubstituted C6 to C30 arylene group or a substituted or unsubstituted C3 to C30 heteroarylene group,

Y ₁ is a single bond; A substituted or unsubstituted C1 to C30 alkylene group; A substituted or unsubstituted C2-C30 alkenylene group; At least one of the methylene (-CH ₂ -) is replaced by a sulfonyl (-S (═O) ₂ -), carbonyl (-C (═O) -), ether (-O-), sulfide (-S (= O) -), ester (-C (= O) O-), amide (-C (= O) NR-) wherein R is hydrogen or a C1 to C10 linear or branched alkyl group C30 alkylene group or a C2-C30 alkenylene group substituted with imine (-NR-), wherein R is hydrogen or a straight or branched alkyl group having from 1 to 10 carbon atoms, or a combination thereof,

m is an integer of 1 or more,

k1 is 0 or an integer of 1 or more, k2 is an integer of 1 or more,

the sum of m and k2 is 3 or more being an integer, m is no more than the atomic valence of Y _1, the sum of k1 and k2 is no more than the atomic valence of L _1.

The second monomer may be represented by the following general formula (2).

(2)

In Formula 2,

X is a C2 to C30 aliphatic organic group having a carbon-carbon unsaturated bond, a C6 to C30 aromatic organic group having a carbon-carbon double bond or a carbon-carbon triple bond, or a carbon-carbon double bond or a carbon- Is a C3 to C30 alicyclic organic group,

R ² is hydrogen; A substituted or unsubstituted C1 to C30 linear or branched alkyl group; A substituted or unsubstituted C6 to C30 aryl group; A substituted or unsubstituted C3 to C30 heteroaryl group; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted C3 to C30 heterocycloalkyl group; A substituted or unsubstituted C2 to C30 alkenyl group; A substituted or unsubstituted C2 to C30 alkynyl group; A substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring; A substituted or unsubstituted C3 to C30 heterocycloalkyl group having a double bond or a triple bond in the ring; A C3 to C30 alicyclic organic group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups; A C3 to C30 heterocycloalkyl group substituted with C2 to C30 alkenyl group or C2 to C30 alkynyl group; A hydroxy group; NH ₂ ; A substituted or unsubstituted C1 to C30 amine group (-NRR ', wherein R and R' are, independently of each other, hydrogen or a C1 to C30 linear or branched alkyl group); Isocyanate group; An isocyanurate group; (Meth) acryloxy group; halogen; -ROR 'wherein R is a substituted or unsubstituted C1 to C20 alkylene group and R' is hydrogen or a C1 to C20 linear or branched alkyl group; Acyl halide (-RC (= O) X wherein R is a substituted or unsubstituted alkylene group and X is halogen; -C (= O) OR 'wherein R' is hydrogen or a C1 to C20 linear or branched alkyl group; -CN; Or -C (= O) ONRR ', wherein R and R' are, independently from each other, hydrogen or a C1 to C20 linear or branched alkyl group,

L ₂ represents a single bond, a carbon atom, a substituted or unsubstituted C1 to C30 alkylene group, a substituted or unsubstituted C6 to C30 cycloalkylene group, a substituted or unsubstituted C6 to C30 cycloalkenylene group, An unsubstituted C6 to C30 arylene group, or a substituted or unsubstituted C3 to C30 heteroarylene group,

Y ₂ is a single bond; A substituted or unsubstituted C1 to C30 alkylene group; A substituted or unsubstituted C2-C30 alkenylene group; Or at least one of methylene (-CH ₂ -) is replaced by a sulfonyl (-S (═O) _2- ), carbonyl (-C (═O) -), ether (-O-), sulfide (-S (= O) -), ester (-C (= O) O-), amide (-C (= O) NR-) wherein R is hydrogen or a straight or branched C30 alkylene group or C2 to C30 alkenylene group substituted with imine (-NR-) (wherein R is hydrogen or a straight or branched alkyl group having from 1 to 10 carbon atoms) or a combination thereof, n is an integer of 1 or more,

k3 is 0 or an integer of 1 or more, k4 is an integer of 1 or more,

The sum of n and k4 is an integer greater than or equal to 3, n does not exceed the atomic number of Y ₂ , and the sum of k 3 and k ₄ does not exceed the atomic value of L ₂ .

The polymerizable monomer and the polymerizable oligomer may have hydrophilic residues.

In one embodiment, the semiconductor nanocrystalline composition does not include inorganic oxide particles.

In another embodiment, the semiconductor nanocrystal composition may further comprise an inorganic oxide. The inorganic oxide may be particles.

The inorganic oxide may be selected from silica, alumina, titania, zirconia, zinc oxide, and combinations thereof.

The inorganic oxide may be included in an amount of about 1% by weight or more based on the total weight of the composition.

The inorganic oxide may be included in an amount of up to about 20 wt%, e.g., up to about 15 wt%, based on the total weight of the composition.

In another embodiment, the semiconductor nanocrystal-polymer composite comprises a semiconductor nanocrystal; Organic additives; And a polymerization product of one or more polymerizable components selected from a polymerizable monomer and a polymerizable oligomer, wherein the haze value is 40% or more.

The semiconductor nanocrystals may comprise a Group II-VI compound, a Group III-V compound, a Group IV-VI compound, a Group IV compound, or a combination thereof.

The semiconductor nanocrystals may be semiconductor nanocrystals emitting green light or red light.

Wherein the organic additive is selected from the group consisting of an amine having at least one C8 to C30 alkyl or alkenyl group, a phosphine having at least one C8 to C30 alkyl or alkenyl group, a phosphine oxide substituted with at least one C8 to C30 alkyl group, Lt; / RTI >

The organic additive may be included in an amount of about 0.05 wt% to about 10 wt% based on the total weight of the polymerizable component.

The polymerizable monomer may be a mixture of a first monomer having at least two thiol (SH) groups at the ends thereof and a second monomer having at least two carbon-carbon unsaturated bonds at the ends thereof, an acrylate monomer, a methacrylate monomer, Based monomer, an epoxy-based monomer, a silicone-based monomer, or a combination thereof. The polymerizable oligomer may be at least one selected from the group consisting of an acrylate oligomer, a methacrylate oligomer, a urethane (meth) acrylate oligomer, Based oligomers, silicone-based oligomers, or combinations thereof.

In one embodiment, the semiconductor nanocrystal-polymer composite does not comprise inorganic oxide particles.

In another embodiment, the semiconductor nanocrystal-polymer composite may further comprise an inorganic oxide. The inorganic oxide may be in the form of particles.

The inorganic oxide may be selected from silica, alumina, titania, zirconia, zinc oxide, and combinations thereof. The inorganic oxide may comprise from about 1% to about 20% by weight, based on the total weight of the composite.

In one embodiment, the backlight unit for a liquid crystal display device comprises:

LED light source; And

And a light switching layer provided so as to be spaced apart from the LED light source so as to convert light incident from the LED light source into white light,

/ RTI >

The light conversion layer comprises the semiconductor nanocrystal-polymer complex described above,

The backlight unit may further include a light guide panel disposed between the LED light source and the light conversion layer.

The backlight unit may further include a diffusion plate on the light guide plate, and the light conversion layer may be disposed between the light guide plate and the diffusion plate or on the diffusion plate (opposite to the side where the light guide plate is located).

The light conversion layer may be a film of the above-mentioned semiconductor nanocrystal polymer composite; And at least one of a first polymer film and a second polymer film disposed on at least one side of the film, wherein the first polymer film and the second polymer film are made of a polyester, a cyclic olefin polymer, COP), a polymer obtained by polymerizing a first monomer having at least two thiol (SH) groups at the terminal thereof and a second monomer having at least two carbon-carbon unsaturated bonds at the terminal thereof, and a polymer selected from a combination thereof .

At least one of the first polymer film and the second polymer film may further include an inorganic oxide.

The first polymer film and the second polymer film may have irregularities on a surface not in contact with the light conversion layer.

In another embodiment, the liquid crystal display device further comprises:

LED light source;

A light diverting layer provided so as to be spaced apart from the LED light source and converting light incident from the LED light source into white light and emitting the light to the liquid crystal panel; And

And a liquid crystal panel for forming an image using light incident from the light conversion layer

The light conversion layer includes the above-described semiconductor nanocrystal-polymer composite.

The liquid crystal display device may further include a light guide plate positioned between the LED light source and the light conversion layer.

In the case of the aforementioned semiconductor nanocrystal composition and the complex of semiconductor nanocrystal-polymer, it can have improved stability with high luminance. By incorporating an organic additive in a semiconductor nanocrystal that has been synthesized in a colloidal state to remove excess organic matter, aggregation of nanocrystals in the semiconductor nanocrystal-polymer composite can be prevented, optical path length of the light source can be increased, High luminance can be achieved when applied. In addition, regardless of the method of synthesizing semiconductor nanocrystals, the type and amount of the organic material in the composite can be controlled and reproducibility can be secured.

FIG. 1 schematically illustrates a process for producing a semiconductor nanocrystal-polymer composite according to one embodiment.
2 schematically shows a sheet including a semiconductor nanocrystal-polymer composite film according to one embodiment.
Figure 3 shows the haze measurement results of semiconductor nanocrystal-composite films prepared by adding different kinds and amounts of organic additives.
Fig. 4 compares the brightness of a backlight unit (BLU) including a semiconductor nanocrystal-composite film prepared by adding different kinds and amounts of organic additives.
Figure 5 compares the brightness of BLUs comprising semiconductor nanocrystal-composite films prepared by adding different types and amounts of organic additives.
FIG. 6 is a graphical illustration of the change in luminance value in a BLU with semiconductor nanocrystal-composite film versus negative additive amount;
FIG. 7 shows the results of driving reliability evaluation of a backlight unit including a semiconductor nanocrystal-composite film prepared by adding different kinds and amounts of organic additives.
8 schematically shows a liquid crystal display device including a BLU according to one embodiment.
Fig. 9 schematically shows a liquid crystal display device including a BLU according to another embodiment.
10 shows the haze of the semiconductor nanocrystal polymer composite films of Comparative Example 4, Comparative Examples 5 and 9.
Fig. 11 shows the luminance of BLU including the semiconductor nanocrystal polymer composite film of Comparative Example 4, Comparative Example 5 and Example 9. Fig.
Figs. 12 and 13 show TGA and DTGA analysis results of the bare semiconductor nanocrystals (after the second centrifugation) prepared in Reference Example and compositions prepared by adding TOA thereto, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Thus, in some implementations, well-known techniques are not specifically described to avoid an undesirable interpretation of the present invention. Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise. Whenever a component is referred to as "including" an element throughout the specification, it is to be understood that the element may include other elements, not the exclusion of any other element, unless the context clearly dictates otherwise.

Also, singular forms include plural forms unless the context clearly dictates otherwise.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. Like parts are designated with like reference numerals throughout the specification.

Whenever a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle.

Refers to an alkyl group having from 1 to 30 carbon atoms, a C2 to C30 alkynyl group, a C6 to C30 aryl group, a C7 to C30 alkylaryl group, a C1 to C30 A C3 to C30 cycloalkenyl group, a C6 to C30 cycloalkynyl group, a C2 to C30 heteroaryl group, a C3 to C30 cycloalkyl group, a C3 to C15 cycloalkenyl group, a C6 to C30 cycloalkynyl group, a C2 to C30 heteroaryl group, (-F, -Cl, -Br or -I), a hydroxy group (-OH), a nitro group (-NO ₂ ), a cyano group (-CN), an amino group (NRR ' R 'is independently hydrogen or a C1 to C6 alkyl groups each other), azido (-N _3), an amidino group _{(-C (= NH) NH 2} ), hydrazino groups (-NHNH _2), hydride tank group ( = N (NH _2), aldehyde (-C (= O) H) , a carbamoyl group, a thiol group, an ester group (-C (= O) oR, where R is C1 to C6 alkyl group or a C6 to C12 aryl group) , Reubok group or its salt, a sulfonic acid group (-SO ₃ H) or a salt thereof, phosphate (-PO ₃ H ₂₎ or its salt (-PO ₃ (-SO ₃ M, where M are the organic or inorganic cation), MH or -PO ₃ M ₂ wherein M means substituted with a substituent selected from an organic or inorganic cation Im), and combinations thereof.

"Hetero" means one to four heteroatoms selected from N, O, S, Si and P in the ring unless otherwise defined below. The total member of the ring may be from 3 to 10. If multiple rings are present, each ring can be an aromatic ring, a saturated or partially saturated ring or multiple rings (fused rings, pendant rings, spiacyclic rings, or combinations thereof). The heterocycloalkyl group may be at least one non-aromatic ring containing a heteroatom, and the heteroaryl group may be at least one aromatic ring containing a heteroatom. Non-aromatic and / or carbocyclic rings may be present in the heteroaryl group if the at least one ring is an aromatic ring containing a heteroatom.

As used herein, an "alkylene group" is a straight or branched chain saturated or unsaturated aliphatic hydrocarbon group having two or more valances, optionally including one or more substituents. As used herein, the term "arylene group" refers to a functional group that optionally contains one or more substituents and has at least two bond valences formed by the removal of at least two hydrogens in one or more aromatic rings. &Quot; Aliphatic organic group " means a C1 to C30 linear or branched alkyl group, "aromatic organic group" means C6 to C30 aryl group or C2 to C30 heteroaryl group, A C3 to C30 cycloalkyl group, a C3 to C30 cycloalkenyl group, and a C3 to C30 cycloalkynyl group.

As used herein, the term " combination thereof "means a mixture, a laminate, a composite, an alloy, a blend, a reaction product, and the like of the composition.

In the present specification, (meth) acrylate means acrylate and / or methacrylate.

The semiconductor nanocrystal composition provided according to an embodiment of the present invention includes semiconductor nanocrystals; Organic additives; And at least one polymerizable component selected from polymerizable monomers, polymerizable oligomers, and combinations thereof, wherein the composition has a haze of at least 40% after polymerization.

The haze value may be a value measured for a polymer film made from the composition and having a thickness of 100 占 퐉 or less (e.g., 50 占 퐉 or less, or 20 占 퐉 or less). The haze value represents the ratio of light scattered in a direction other than a straight line with respect to the entire transmitted light. After the polymerization, the semiconductor nanocrystal composition may have a haze value of about 95% or less. In one embodiment, a polymer film having a thickness of 100 [mu] m made from the composition and having a haze value can range from 45% to 95%, as measured in the manner described in the Examples below.

In such a composition, the organic additive may be present in the composition independently from the semiconductor nanocrystal, without coordinating or surrounding the surface of the semiconductor nanocrystal (e.g., as opposed to a capping agent). The composition may exhibit a peak of the organic compound at a position different from a peak indicated by a thermogravimetric analysis of a capping agent (or a ligand compound) that coordinates or surrounds the surface of the semiconductor nanocrystal.

The polymerizable component may be one that can be photopolymerized. In the semiconductor nanocrystal composition, the polymerizable component may include a polymerizable monomer and a polymerizable oligomer.

The semiconductor nanocrystals may comprise Group II-VI compounds, Group III-V compounds, Group IV-VI compounds, Group IV elements or compounds, or combinations thereof.

The II-VI group compound is selected from the group consisting of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS and mixtures thereof; A trivalent element selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, Small compounds; And a silane compound selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and mixtures thereof. The III-V compound may be selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb and mixtures thereof. A trivalent compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb and mixtures thereof; And a silicate compound selected from the group consisting of GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and mixtures thereof. have. The IV-VI compound may be selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; A triple compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; And a silane compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof. The Group IV or compound is a monosource material selected from the group consisting of Si, Ge and combinations thereof; And these elemental compounds selected from the group consisting of SiC, SiGe, and mixtures thereof.

The elemental compound, the trivalent compound, or the photovoltaic compound may be present in the particle at a uniform concentration, or may be present in the same particle by dividing the concentration distribution into different states partially. One semiconductor nanocrystal may have a core / shell structure surrounding other semiconductor nanocrystals. The interface between the core and the shell may have a concentration gradient in which the concentration of the element existing in the core or shell becomes lower toward the center. In addition, the semiconductor nanocrystals may have a structure including one semiconductor nanocrystal core and a multi-layered shell surrounding the one semiconductor nanocrystal core. Wherein the multi-layered shell structure has a shell structure of two or more layers wherein each layer may have a single composition or alloy or concentration gradient.

In addition, the semiconductor nanocrystals may have a structure in which the material composition of the shell is larger than that of the core, so that the quantum confinement effect is effectively exhibited. In the case of constructing a multi-layered shell, the shell on the outer side of the core may have a larger energy band gap than the shell near the core, and the semiconductor nanocrystals may have an ultraviolet to infrared wavelength range.

Semiconductor nanocrystals may have a quantum efficiency of greater than about 50%, such as greater than about 70%, or greater than about 90%. The luminous efficiency of the device can be improved in the above range.

In addition, the half width of the emission wavelength spectrum of the semiconductor nanocrystal can be designed to be wide or narrow according to the application field, and the semiconductor nanocrystals can have a narrow spectrum in order to improve the color purity and color reproducibility in the display. The semiconductor nanocrystals may have a half-width of the emission wavelength spectrum of about 45 nm or less, for example, about 40 nm or less, or about 30 nm or less. The color purity and color reproducibility of the device can be improved in the above range.

The nanocrystals may have a particle size of about 1 nm to about 100 nm (the longest portion size if not spherical). For example, the nanocrystals may have a particle size of about 1 nm to about 20 nm (e.g., 1 nm to 10 nm) (the longest portion size if not spherical).

The shape of the nanocrystals is not particularly limited and is generally used in the art. For example, the nanocrystals may be in the form of spheres, pyramids, multi-arcs, cubic, elliptical, tetrahedral, octahedral, cylindrical, But are not limited to, a polygonal pillar-like shape, a conical shape, a columnar shape, a tubular shape, a helical shape, a funnel shape, a dendritic shape, Shaped < / RTI > Nanocrystals can be nanoparticles, nanotubes, nanowires, nanofibers, nanoplates, nanosheets, and the like.

In addition, the nanocrystals can be synthesized by any method and can be synthesized by, for example, the methods described below, but are not limited thereto.

In a non-limiting example, nanocrystalline semiconductor nanocrystals can be synthesized through a wet chemical process. In the chemical wet process, the precursor materials are reacted in an organic solvent to grow crystal grains. At this time, the organic solvent or the ligand compound is naturally coordinated to the surface of the semiconductor nanocrystals to control crystal growth. Since the organic solvent coordinated on the surface of the nanocrystal may affect the stability in the device, the excess organic substance not coordinated on the surface of the nanocrystals is poured into an excessive amount of non-solvent, and the obtained mixture is centrifuged It can be removed by a separation process. Specific examples of the non-solvent include acetone, ethanol, methanol, and the like, but are not limited thereto. The amount of organics coordinated to the surface of the nanocrystals after removing the excess organic material may be up to 35 wt%, e.g., up to 25 wt% of the weight of the nanocrystals. Such organic materials may include ligand compounds, organic solvents, or combinations thereof. The ligand compound is not particularly limited and may be any organic compound used as a ligand compound in a chemical wet process. For example, the ligand compound may be selected from the group consisting of RCOOH, RNH ₂ , R ₂ NH, R ₃ N, RSH, R ₃ PO, R ₃ P, ROH, RCOOR ', RCONH ₂ , RCONHR' OH) ₂ , R ₂ POOH wherein R, R ', R "are each independently a C1 to C24 alkyl group, a C2 to C24 alkenyl group or a C6 to C20 aryl group, or combinations thereof . Organic ligand compounds coordinate the surface of the prepared nanocrystals, which not only allows the nanocrystals to be well dispersed in the solution, but can also affect the luminescence and electrical properties. Specific examples of the organic ligand compound include thiols such as methanethiol, ethanethiol, propanethiol, butanethiol, pentanethiol, hexanethiol, octanethiol, dodecanethiol, hexadecanethiol, octadecanethiol and benzylthiol; An amine such as methane amine, ethane amine, propane amine, butane amine, pentane amine, hexane amine, octane amine, dodecane amine, hexadecyl amine, octadecyl amine, dimethyl amine, diethyl amine, dipropyl amine, ; Alcohols such as methanol, ethanol, propanol and butanol; An acid such as methane acid, ethane acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid or benzoic acid; Esters such as methyl acetate, ethyl acetate, methyl propionate, ethyl propionate and the like; Amides such as methyl acetamide, ethyl acetamide, methyl propionamide, ethyl propionamide and the like; Nitriles such as acetonitrile, propionitrile, butyronitrile and the like; Phosphines such as methylphosphine, ethylphosphine, propylphosphine, butylphosphine and pentylphosphine; Phosphine oxide compounds such as methylphosphine oxide, ethylphosphine oxide, propylphosphine oxide, and butylphosphine oxide; Diphenylphosphine, triphenylphosphine compound or an oxide compound thereof; Phosphonic acid, and the like, but are not limited thereto. The organic ligand compound may be used alone or in a mixture of two or more.

The solvent is not particularly limited and may be any compound used as a solvent in a chemical wet process. For example, the solvent may be selected from C6 to C22 primary amines such as hexadecylamine; C6 to C22 secondary amines such as dioctylamine; C6 to C40 tertiary amines such as trioctylamine; Nitrogen-containing heterocyclic compounds such as pyridine; C6 to C40 aliphatic hydrocarbons (e.g., alkanes, alkenes, alkynes, etc.) such as hexadecane, octadecane, octadecene, squalane and the like; C6 to C30 aromatic hydrocarbons such as phenyldodecane, phenyltetradecane, and phenylhexadecane; Phosphine substituted with a C6 to C22 alkyl group such as trioctylphosphine; Phosphine oxides substituted with C6 to C22 alkyl groups such as trioctylphosphine oxide; But are not limited to, C12 to C22 aromatic ethers such as phenyl ether, benzyl ether, and combinations thereof.

The organic additive may be at least one selected from the group consisting of primary amines having C8 or higher (for example, C8-C30) alkyl or alkenyl groups such as octylamine, oleylamine and hexadecylamine, C8 or higher such as dioctylamine and didecylamine (For example, C8-C30) alkyl group or an alkenyl group having a C8 or higher (e.g., C8-C30) alkyl group such as trioctylamine or tridodecylamine; ), Primary phosphine substituted with an alkyl group of C8 or higher (e.g., C8-C30 or C8 to C22), dioctylphosphine or the like having at least one C8 or higher alkyl or alkenyl group (For example, C8-C30 or C8 to C22) alkyl group such as secondary phosphine or trioctylphosphine substituted with an alkyl group having C8 or more (for example, C8-C30 or C8 to C22) Phosphine oxide having at least one C8 or higher alkyl or alkenyl group (e.g., C8-C3 (For example, C8-C30 or C8 to C22) alkyl groups such as primary phosphine oxide substituted with an alkyl group having 0 or more than C8 (for example, C8 to C22), dioctylphosphine oxide and the like (E. G., C8-C30 or C8 to C22) alkyl groups such as secondary phosphine oxide, trioctylphosphine oxide, and the like, or a combination thereof.

The organic additive may be present in an amount of from about 0.05% to about 10% by weight, for example, from about 0.1% to about 10% by weight, based on the total weight of the polymerizable monomer (and optionally the polymerizable oligomer) About 6% by weight, or about 0.1% by weight to 5% by weight. The composition in which the organic additive is contained in the above-mentioned content can significantly improve haze and brightness while maintaining excellent mechanical / optical properties of the composite.

The polymerizable component may be a mixture of a first monomer having at least two thiol (SH) groups at the ends thereof and a second monomer having at least two carbon-carbon unsaturated bonds at the ends thereof, or a mixture of a (meth) acrylate monomer or oligomer, Urethane acrylate-based monomer or oligomer, epoxy-based monomer or oligomer, silicone-based monomer or oligomer.

The (meth) acrylate monomer may be at least one selected from the group consisting of isobornyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, benzyl (meth) acrylate, norbornyl (Meth) acrylate, n-hexyl (meth) acrylate, iso-octyl (meth) acrylate, butyl (meth) acrylate, adamantyl acrylate Acrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate,

The polymerizable oligomer is an oligomer having one or more, for example, two or more polymerizable functional groups (e.g., (meth) acrylate group, vinyl group, etc.). The polymerizable oligomer may be selected from the group consisting of urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, acrylic (meth) acrylate, polybutadiene (Meth) acrylate, melamine (meth) acrylate, and combinations thereof. The molecular weight of the polymerizable oligomer is not particularly limited and may be appropriately selected. For example, the molecular weight of the polymerizable oligomer may be 1,000 to 20,000 g / mol, such as 1,000 to 10,000 g / mol, but is not limited thereto. Such polymerizable oligomers can be synthesized by a known method or are commercially available.

The first monomer having at least two thiol (SH) groups at the terminal may be represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

R ¹ is hydrogen; A substituted or unsubstituted C1 to C30 linear or branched alkyl group; A substituted or unsubstituted C6 to C30 aryl group; A substituted or unsubstituted C3 to C30 heteroaryl group; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted C3 to C30 heterocycloalkyl group; A substituted or unsubstituted C2 to C30 alkenyl group; A substituted or unsubstituted C2 to C30 alkynyl group; A substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring; A substituted or unsubstituted C3 to C30 heterocycloalkyl group having a double bond or a triple bond in the ring; A C3 to C30 alicyclic organic group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups; A C3 to C30 heterocycloalkyl group substituted with C2 to C30 alkenyl group or C2 to C30 alkynyl group; A hydroxy group; NH ₂ ; A substituted or unsubstituted C1 to C30 amine group (-NRR ', where R and R' are, independently of each other, hydrogen or a C1 to C30 linear or branched alkyl group); Isocyanate group; An isocyanurate group; (Meth) acrylate groups; halogen; -ROR 'wherein R is a substituted or unsubstituted C1 to C20 alkylene group and R' is hydrogen or a C1 to C20 linear or branched alkyl group; Acyl halide (-RC (= O) X wherein R is a substituted or unsubstituted alkylene group and X is halogen; -C (= O) OR ', wherein R' is hydrogen or a C1 to C20 linear or branched alkyl group; -CN; Or -C (= O) ONRR ', wherein R and R' independently from each other are hydrogen or a C1 to C20 linear or branched alkyl group,

L ₁ represents a single bond, a carbon atom, a substituted or unsubstituted C1 to C30 alkylene group, a substituted or unsubstituted C3 to C30 (eg, C6 to C30) cycloalkylene group, a substituted or unsubstituted C3 to C30 C6 to C30), a substituted or unsubstituted C6 to C30 arylene group or a substituted or unsubstituted C3 to C30 heteroarylene group,

Y ₁ is a single bond; A substituted or unsubstituted C1 to C30 alkylene group; A substituted or unsubstituted C2-C30 alkenylene group; At least one of the methylene (-CH ₂ -) is replaced by a sulfonyl (-S (═O) ₂ -), carbonyl (-C (═O) -), ether (-O-), sulfide (-S (= O) -), ester (-C (= O) O-), amide (-C (= O) NR-) wherein R is hydrogen or a C1 to C10 linear or branched alkyl group C30 alkylene group or a C2-C30 alkenylene group substituted with imine (-NR-), wherein R is hydrogen or a straight or branched alkyl group having from 1 to 10 carbon atoms, or a combination thereof,

m is an integer of 1 or more,

k1 is 0 or an integer of 1 or more, k2 is an integer of 1 or more,

the sum of m and k2 is 3 or more being an integer, m is no more than the atomic valence of Y _1, the sum of k1 and k2 is no more than the atomic valence of L _1.

The second monomer may be represented by the following general formula (2).

(2)

In Formula 2,

X is a C2 to C30 aliphatic organic group having a carbon-carbon unsaturated bond, a C6 to C30 aromatic organic group having a carbon-carbon double bond or a carbon-carbon triple bond, or a carbon-carbon double bond or a carbon- Is a C3 to C30 alicyclic organic group,

R ² is hydrogen; A substituted or unsubstituted C1 to C30 linear or branched alkyl group; A substituted or unsubstituted C6 to C30 aryl group; A substituted or unsubstituted C3 to C30 heteroaryl group; A substituted or unsubstituted C3 to C30 cycloalkyl group; A substituted or unsubstituted C3 to C30 heterocycloalkyl group; A substituted or unsubstituted C2 to C30 alkenyl group; A substituted or unsubstituted C2 to C30 alkynyl group; A substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring; A substituted or unsubstituted C3 to C30 heterocycloalkyl group having a double bond or a triple bond in the ring; A C3 to C30 alicyclic organic group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups; A C3 to C30 heterocycloalkyl group substituted with C2 to C30 alkenyl group or C2 to C30 alkynyl group; A hydroxy group; NH ₂ ; A substituted or unsubstituted C1 to C30 amine group (-NRR ', where R and R' are, independently of each other, hydrogen or a C1 to C30 linear or branched alkyl group); Isocyanate group; An isocyanurate group; (Meth) acryloxy group; halogen; -ROR 'wherein R is a substituted or unsubstituted C1 to C20 alkylene group and R' is hydrogen or a C1 to C20 linear or branched alkyl group; Acyl halide (-RC (= O) X wherein R is a substituted or unsubstituted alkylene group and X is halogen; -C (= O) OR ', wherein R' is hydrogen or a C1 to C20 linear or branched alkyl group; -CN; Or -C (= O) ONRR ', wherein R and R' independently from each other are hydrogen or a C1 to C20 linear or branched alkyl group,

L ₂ represents a single bond, a carbon atom, a substituted or unsubstituted C1 to C30 alkylene group, a substituted or unsubstituted C3 to C30 (eg C6-C30) cycloalkylene group, a substituted or unsubstituted C3 to C30 C6-C30) cycloalkenylene group, a substituted or unsubstituted C6 to C30 arylene group or a substituted or unsubstituted C3 to C30 heteroarylene group,

Y ₂ is a single bond; A substituted or unsubstituted C1 to C30 alkylene group; A substituted or unsubstituted C2-C30 alkenylene group; Or at least one of methylene (-CH ₂ -) is replaced by a sulfonyl (-S (═O) _2- ), carbonyl (-C (═O) -), ether (-O-), sulfide (-S (= O) -), ester (-C (= O) O-), amide (-C (= O) NR-) wherein R is hydrogen or a straight or branched C30 alkylene group or C2 to C30 alkenylene group substituted with imine (-NR-) (wherein R is hydrogen or a straight or branched alkyl group having from 1 to 10 carbon atoms) or a combination thereof, n is an integer of 1 or more,

k3 is 0 or an integer of 1 or more, k4 is an integer of 1 or more,

The sum of n and k4 is an integer greater than or equal to 3, n does not exceed the atomic number of Y ₂ , and the sum of k 3 and k ₄ does not exceed the atomic value of L ₂ .

The polymerizable monomer may be one having a hydrophilic moiety.

Examples of the first monomer of Formula 1 include monomers of Formula 1-1.

[Formula 1-1]

In Formula 1-1,

L _{1 '} is a carbon, a substituted or unsubstituted C6 to C30 arylene group, for example, a substituted or unsubstituted phenylene group; A substituted or unsubstituted C3 to C30 heteroarylene group such as a trioxotriazine group; A substituted or unsubstituted C3 to C30 cycloalkylene group; A substituted or unsubstituted C3 to C30 heterocycloalkylene group,

Y _a to Y _d each independently represent a substituted or unsubstituted C1 to C30 alkylene group; A substituted or unsubstituted C2-C30 alkenylene group; Or at least one of methylene (-CH ₂ -) is replaced by a sulfonyl (-S (═O) _2- ), carbonyl (-C (═O) -), ether (-O-), sulfide (-S (= O) -), ester (-C (= O) O-), amide (-C (= O) NR-) wherein R is hydrogen or a straight or branched C30 alkylene group or C2 to C30 alkenylene group substituted with imine (-NR-) (wherein R is hydrogen or a straight or branched alkyl group having from 1 to 10 carbon atoms) or a combination thereof,

R _a to R _d are R ¹ or SH in formula (1), and at least two of R _a to R _d are SH.

More specific examples of the first monomer of Formula 1 include the compounds represented by Formulas 1-2 to 1-5 below.

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

In Formula 2,

X is a C1 to C30 aliphatic organic group having a carbon-carbon double bond or a carbon-carbon triple bond, a C6 to C30 aromatic organic group having a carbon-carbon double bond or a carbon-carbon triple bond or a carbon- May be a C3 to C30 alicyclic organic group having a carbon-carbon triple bond. X is an acryloxy group; A methacryloxy group; C2 to C30 alkenyl groups; An alkynyl group of C2 to C30; A substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring; A substituted or unsubstituted C3 to C30 heterocycloalkyl group having a double bond or a triple bond in the ring; A C3 to C30 alicyclic organic group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups; Or a C3 to C30 heterocycloalkyl group substituted with C2 to C30 alkenyl groups or C2 to C30 alkynyl groups.

In the definition of X in the above formula (2), the alkenyl group may be selected from a vinyl group, an allyl group, a 2-butenyl group, or a combination thereof. The substituted or unsubstituted C3 to C30 alicyclic organic group having a double bond or a triple bond in the ring may be a norbornene group, a maleimide group, a nadimide group, a tetrahydrophthalimide group, . ≪ / RTI >

In the general formula (2), L ₂ represents a substituted or unsubstituted pyrrolidinyl group, a substituted or unsubstituted tetrahydrofuranyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted pyrimidyl group, a substituted or unsubstituted A substituted or unsubstituted thiazolyl group, a substituted or unsubstituted thiazolidinyl group, a substituted or unsubstituted thiazolidinyl group, a substituted or unsubstituted thiazolidinyl group, a substituted or unsubstituted thiazolyl group, a substituted or unsubstituted thiazolidinyl group,

Specific examples of the second monomer of Formula 2 include the following Formula 2-1 and Formula 2-2.

[Formula 2-1]

[Formula 2-2]

In Formulas (2-1) and (2-2), Z ₁ to Z ₃ each independently represent * -Y ₂ - (X) _n in Formula 2.

More specific examples include compounds represented by the following formulas (2-3) to (2-5).

[Formula 2-3]

[Chemical Formula 2-4]

[Chemical Formula 2-5]

The first monomer and the second monomer may be present such that the carbon-carbon unsaturated bond of the thiol group of the first monomer and the second monomer is in a molar ratio of 1: about 0.75 to 1: about 1.25. When the first and second monomers are used in the above range, a polymer having a high density network and having excellent mechanical strength and physical properties can be provided.

Wherein the polymer comprises a third monomer having one thiol group at the terminal; A fourth monomer having one carbon-carbon unsaturated bond at the terminal thereof; Or all of these may be further polymerized.

The third monomer is a compound wherein m and k2 are each 1 in Formula (1), and the fourth monomer is a compound in which n and k4 are each 1 in Formula (2).

The first monomer and the second monomer, and optionally the third monomer and / or the fourth monomer, may be polymerized in the presence of an initiator to promote the cross-linking reaction of the thiol group and the carbon-carbon unsaturated bond. The initiator may be selected from the group consisting of phospine oxide, alpha-amino ketone, phenylglyoxylate, monoacyl phosphine, benzyldimethyl-ketal, Hydroxyketone, and the like.

The first monomer and the second monomer can be polymerized (for example, cured) at a room temperature for a short time, so that a high-temperature process that can lower the stability of the luminescent particles can be omitted. In addition, the polymerization product forms a dense crosslinked structure and can effectively block external factors such as oxygen or water.

The semiconductor nanocrystal composition may include one or more additional components such as a flame retardant, a UV light stabilizer, a heat stabilizer, an antioxidant, a diffusing agent, or a combination thereof. The type / content of such additional component (s) may vary depending on the particular application. For example, each additional component may be present in an amount of from 0.005 to 5 wt%, based on the total weight of the semiconductor nanocrystal composition.

In another embodiment, the semiconductor nanocrystal-polymer composite comprises a semiconductor nanocrystal; Organic additives; And a polymerization product of a polymerizable monomer or a mixture of a polymerizable monomer and a polymerizable oligomer, and has a haze value of 40% or more. The semiconductor nanocrystal-polymer composite can be prepared by performing polymerization of a polymerizable monomer / oligomer (for example, by heat treatment or UV irradiation) from the above-described semiconductor nanocrystal composition. Therefore, the contents of semiconductor nanocrystals, organic additives, polymerizable monomers and polymerizable oligomers are as described above. Polymerization conditions of the polymerizable monomer / oligomer can be appropriately selected in consideration of the type of the monomer / oligomer used and are not particularly limited. When the polymerizable monomer / oligomer can be photopolymerized, the polymerization can be initiated by UV irradiation.

The amount of the semiconductor nanocrystals in the semiconductor nanocrystal composition or the semiconductor nanocrystal-polymer composite is not particularly limited and may be appropriately selected. For example, the amount of semiconductor nanocrystals may be at least 0.1 wt.%, Based on the weight of the semiconductor nanocrystal-composition or semiconductor nanocrystal-polymer composite, but is not limited thereto. The amount of the semiconductor nanocrystals may be 20 wt% or less based on the weight of the semiconductor nanocrystal composition or the semiconductor nanocrystal-polymer composite, but is not limited thereto.

1 schematically illustrates one non-limiting embodiment of the process for producing the semiconductor nanocrystal-polymer composite. Referring to FIG. 1, semiconductor nanocrystals (ie, QDs) having an organic content of 35 wt% or less are obtained by removing excess organic substances from semiconductor nanocrystals synthesized in a colloid state (hereinafter also referred to as QD or QD). The method for removing organic matter is as described above. Dispersing the nanocrystals in a dispersion solvent, mixing the organic additives with the polymerizable monomer, and curing the mixture. Specific examples of the dispersion solvent include, but are not limited to, chloroform, hexene, acrylate monomers, or combinations thereof.

The mixing method is not particularly limited and may be carried out in various ways such as dispersion, blending, stirring, sonication, sparging, milling, shaking, centrifugal circulating pump mixing, mixing, blade mixing, impact mixing, jet mixing, homogenization, co-sparing, high sheer mixing, Multipass mixing, and the like.

By using semiconductor nanocrystals as color-down converting materials for LEDs, superior color purity can be obtained compared to existing phosphors. The quantum efficiency of the theoretical QD is 100% and the half-width of 45 nm or less is possible, and the color purity is high. Therefore, it is expected that the color reproducibility is improved when applied to the light emitting device compared with the conventional inorganic phosphor. However, the conventional inorganic phosphor is a particle having a micron size, whereas a QD having a nanometer size has a short life span. However, when QD is applied to a light emitting device, it is necessary to secure a lifetime of about 30,000 hours or more to develop a device that can be practically applied. In particular, when applying colloidal QDs to LEDs, it is important to preserve the passivation layer of the QD surface to maintain their efficiency and color reproducibility by maintaining their high efficiency and color purity . Currently, when dispensing a light emitting material to an LED chip, a method of simply mixing an encapsulation material with a light emitting material in powder form or using a dispersant to improve dispersion characteristics is applied. However, the colloidal state of QD is apt to cause aggregation due to low compatibility between silicone used as an encapsulant and organic matters on the surface of the QD, Efficiency reduction occurs. In addition, the amount of organic matters remaining depends on the conditions of synthesis and the degree of purification of QD, so that it is difficult to achieve reproducibility in forming a composite with a polymer. Particularly, when a large amount of organic matter is removed, the ligand compound on the surface of the QD is also removed, and the degradation of the QD and the passivation layer progresses rapidly during long-term driving. To solve these problems, it is necessary to control the kind and amount of organic substances in the formation of a polymer composite. In addition, when the QD-polymer composite is used to down-convert the light of the LED primary light source, the transmission of the primary light source may be restricted or the QD reabsorption There is a problem of luminance reduction.

The semiconductor nanocrystal composition or the semiconductor nanocrystal-polymer composite prepared from the semiconductor nanocrystal composition according to an embodiment can solve the problems of the above-described conventional techniques and achieve high luminance and improved level of stability at the same time. While not intending to be bound by any particular theory, it is believed that the organic additive added to the composition or composite can protect the QD surface to enhance stability to air and moisture and prevent photooxidation. In addition, the organic additive can increase the haze of the composite (e.g., in sheet or film form) without affecting the light transmittance, thereby increasing the optical path length of the primary light source can do. Further, unlike the inorganic oxide particles, the organic additive can provide a composite (film) exhibiting a high haze and a luminance without adversely affecting the light transmittance without substantially affecting the polymerization reaction for producing the composite. Therefore, a high brightness display device can be realized by using such a composite.

As described above, such a semiconductor nanocrystal-polymer composite can be prepared by dispersing the QD in a colloidal state and removing the excess organic matter in an organic solvent or mixing it with an organic additive and a monomer in a powder state, (After removal of the solvent, if necessary), for example, by curing (e.g., UV curing). Alternatively, the QD surface synthesized in a colloidal form can be substituted with a polymer having a chemical structure similar to that of the ligand compound used in synthesis, and then a stable form of the QD-polymer complex can be formed in the above-described manner.

In a non-limiting example, as shown in FIG. 2, various protective films (e.g., barrier layers), such as silica, titania, or the like, may be formed on the prepared semiconductor nanocrystal- Alumina or the like may be coated or laminated to increase the stability.

In another embodiment, the backlight unit for a liquid crystal display device comprises:

LED light source; And

And a light switching layer provided so as to be spaced apart from the LED light source so as to convert light incident from the LED light source into white light,

 / RTI >

The light conversion layer includes the above-described semiconductor nanocrystal-polymer composite. The backlight unit may further include a light guide panel disposed between the LED light source and the light switching layer. The details of the semiconductor nanocrystal-polymer composite are as described above. Hereinafter, a backlight unit and a liquid crystal display device including the same according to an embodiment will be described with reference to the drawings.

8 is a schematic view of a liquid crystal display device 10 including a backlight unit according to one embodiment

Referring to FIG. 8, the liquid crystal display device 10 includes a backlight unit 100 and a liquid crystal panel 500 that forms an image of a predetermined color using white light emitted from the backlight unit 100.

The backlight unit 100 includes a light emitting diode (LED) light source 110, a light converting layer 130 for converting the light emitted from the LED light source 110 into white light, And a light guide plate 120 for guiding the light emitted from the LED light source 110 to the light switching layer 130. Here, the LED light source 110 is composed of a plurality of LED chips emitting light of a predetermined wavelength. The LED light source 110 may be an LED light source emitting blue light or an LED light source emitting ultraviolet light.

A reflector (not shown) may be further disposed on the lower surface of the light guide plate 120.

The light conversion layer 130 is spaced apart from the LED light source 110 by a predetermined distance so that the light emitted from the LED light source 110 is converted into white light and emitted to the liquid crystal panel 500.

The light conversion layer 130 includes the above-described semiconductor nanocrystal-polymer composite. Details of the semiconductor nanocrystal-polymer composite are as described above.

The backlight unit 100 may further include a diffusion plate on the light guide plate 120. The light conversion layer 130 may be disposed between the light guide plate and the diffusion plate or on a diffusion plate opposite to the light guide plate . Materials and structures of the LED light source 110, the light guide plate, the diffusion plate, and the liquid crystal panel are known and commercially available, and are not particularly limited.

The semiconductor nanocrystal-polymer composite included in the light conversion layer 130 may be formed into a film. The film can be manufactured in various thicknesses and shapes by using a mold or by casting.

When the light emitted from the LED light source 110 passes through the light conversion layer 130 including the semiconductor nanocrystal-polymer composite, white light mixed with blue light, green light, and red light can be obtained. When the composition and the size of the semiconductor nanocrystals constituting the light conversion layer 130 are changed, blue light, green light and red light can be controlled at desired ratios, and accordingly white light capable of realizing excellent color reproducibility and color purity can be obtained. . The color coordinates of such white light may have a Cx value in the CIE 1931 color space of about 0.24 to 0.56 and a Cy value in the range of about 0.24 to 0.42.

Meanwhile, the light conversion layer 130 may be formed of a plurality of layers. In this case, the plurality of layers may be arranged to have an emission wavelength of a lower energy toward the LED light source 110. For example, if the LED light source 110 is a blue LED light source, the light conversion layer 130 may be composed of a red light conversion layer and a green light conversion layer that are sequentially stacked in a direction away from the LED light source 110 .

Although not shown in FIG. 8, a diffusion plate, a prism sheet, a microlens sheet, and a brightness enhancement film (for example, a double brightness enhancement film (DBEF)) are formed on the light conversion layer 130 At least one film may be further positioned. The light conversion layer 130 may be formed of at least two films selected from a light guide plate, a diffusion plate, a prism sheet, a micro lens sheet, and a brightness enhancement film (for example, double brightness enhancement film (DBEF) As shown in FIG.

9 schematically shows a liquid crystal display device 20 including a backlight unit 102 according to another embodiment.

9, the light conversion layer 132 may include at least one of the first polymeric film 133 and the second polymeric film 135 on at least one side of the semiconductor nanocrystal- . The second polymer film 135 located below the film 131 may serve as a barrier for preventing the semiconductor nanocrystals from deteriorating from the LED light source 110.

The first polymer film 133 and the second polymer film 135 may be made of a material selected from the group consisting of polyester, a cyclic olefin polymer (COP), a first monomer having at least two thiol (SH) - a polymer obtained by polymerizing a second monomer having at least two carbon unsaturated bonds, and a polymer selected from a combination thereof. Examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. The cyclic olefin polymer means a polymer obtained by polymerizing a chain olefin compound such as ethene and a cyclic olefin monomer such as norbornene or tetracyclododecene. The polymer obtained by polymerizing the first monomer having at least two thiol (SH) groups at the terminal and the second monomer having at least two carbon-carbon unsaturated bonds at the terminal is the same as described above.

At least one of the first polymer film 133 and the second polymer film 135 may further include an inorganic oxide. The inorganic oxide may be selected from silica, alumina, titania, zirconia, and combinations thereof. These inorganic oxides can act as light diffusing materials . The inorganic oxide may be coated on the surfaces of the first polymer film 133 and the second polymer film 135 to a thickness of about 10 to 100 nm.

The first polymer film 133 may have irregularities of a predetermined size on a surface not contacting the film 131 including the semiconductor nanocrystals and the matrix polymer. The second polymer film 135 may also have irregularities of a certain size on a surface not contacting the film 131 including the semiconductor nanocrystals and the matrix polymer. The first polymer film 133 and the second polymer film 135 having the concavities and convexities formed on the surface thereof may diffuse light emitted from the LED light source 110. Therefore, the liquid crystal display device can omit a diffusion plate or a prism sheet existing on the light guide plate 120. However, it goes without saying that another diffuser plate or prism sheet may be further disposed on the light guide plate 120 according to another embodiment of the present invention.

Although not shown in FIG. 9, a diffusion plate, a prism sheet, a microlens sheet, and a brightness enhancement film (for example, double brightness enhancement film (DBEF)) are formed on the light conversion layer 132 At least one film may be further positioned. The light conversion layer 132 may be formed between at least two films selected from a light guide plate, a diffusion plate, a prism sheet, a micro lens sheet, and a brightness enhancement film (for example, a double brightness enhancement film (DBEF) As shown in FIG.

The white light emitted from the backlight units 100 and 102 is incident on the liquid crystal panel 500 side. The liquid crystal panel 500 forms an image of a predetermined color using the white light incident from the backlight units 100 and 102. Here, the liquid crystal panel 500 may have a structure in which a first polarizer 501, a liquid crystal layer 502, a second polarizer 503, and a color filter 504 are sequentially disposed. The white light emitted from the backlight units 100 and 102 is transmitted through the first polarizing plate 501, the liquid crystal layer 502 and the second polarizing plate 503 and the thus transmitted white light is incident on the color filter 504 Thereby forming an image of a predetermined color.

In another embodiment, the liquid crystal display device further comprises:

LED light source;

A light diverting layer provided so as to be spaced apart from the LED light source and converting light incident from the LED light source into white light and emitting the light to the liquid crystal panel;

And

And a liquid crystal panel for forming an image using light incident from the light conversion layer

The light conversion layer includes the above-described semiconductor nanocrystal-polymer composite. The liquid crystal display device may further include a light guide plate positioned between the LED light source and the light conversion layer. The liquid crystal panel is not particularly limited and may include any liquid crystal panel known or commercially available. The details of the liquid crystal display device are as described above.

Hereinafter, specific embodiments of the present invention will be described. It should be noted, however, that the embodiments described below are only intended to illustrate or explain the invention in detail, and the scope of the invention should not be limited thereby.

[ Example ]

Reference Example : Bare semiconductor nanocrystal manufacturing

(1) 0.2 mmol of indium acetate, 0.6 mmol of palmitic acid and 10 mL of 1-octadecene are placed in a reactor and heated to 120 ° C under vacuum. After 1 hour, the atmosphere in the reactor is converted to nitrogen. After heating to 280 ° C, a mixed solution of 0.1 mmol of tris (trimethylsilyl) phosphine (TMS3P) and 0.5 mL of trioctylphosphine is rapidly injected and reacted for 20 minutes. Acetone is added to the reaction solution which is quickly cooled to room temperature, and the precipitate obtained by centrifugation is dispersed in toluene. The obtained InP semiconductor nanocrystals exhibit a first absorption maximum wavelength of 420 to 600 nm.

0.3 mmol (0.056 g) of zinc acetate, 0.6 mmol (0.189 g) of oleic acid and 10 mL of trioctylamine are placed in a reaction flask and vacuum-treated at 120 ° C. for 10 minutes. After replacing the inside of the reaction flask with N ₂ , the temperature is raised to 220 ° C. The toluene dispersion (OD: 0.15) and the S / TOP (0.6 mmol) of the InP semiconductor nanocrystals prepared above were placed in the reaction flask, heated to 280 ° C and reacted for 30 minutes. After completion of the reaction, the reaction solution is rapidly cooled to room temperature to obtain a reactant containing InP / ZnS semiconductor nanocrystals.

(2) Extra ethanol is added to the reactant containing the InP / ZnS semiconductor nanocrystals and centrifuged to remove excess organic substances present in the semiconductor nanocrystal reactant. After centrifugation, discard the supernatant, dissolve the precipitate again in hexane, add excess ethanol, and centrifuge again. The centrifuged sediment is dried and dispersed in chloroform, and the UV-vis absorption spectrum is measured.

(3) The precipitate obtained after centrifugation in (2) is subjected to thermogravimetric analysis (TGA) analysis by raising the temperature to 600 ° C. at a rate of 10 ° C./min under N ₂ atmosphere. The results of thermogravimetric analysis of precipitates after two centrifugations are shown in FIG. 12 and FIG. From the results shown in Figs. 12 and 13, it is confirmed that the amount of organic matter is about 60 wt% based on the weight of the whole sediment after one centrifugation, and the amount of organic matter remaining after centrifugation twice is about 20 wt%.

(4) The composition is prepared by adding 30 grams of trioctylamine to the precipitate obtained by secondary centrifugation in (2). Subjected to the temperature was raised to 10 ℃ / min rate TGA (Thermogravimetric analysis, TGA) analysis of the composition prepared under N ₂ atmosphere to 600 ℃ and The results are shown in Figs.

12 and 13, it is confirmed that the trioctylamine added to the precipitate decomposes at a different temperature from the organic matter remaining in the precipitate (for example, the ligand compound or solvent coordinated to the nanocrystalline particles).

compare Manufacturing example  1 to 3 and Manufacturing example  1 to 2: Preparation of semiconductor nanocrystal compositions

0.89 g of pentaerythritol tetrakis (3-mercaptopropionate): 4T, 1,3,5-triallyl-1,3,5-triazine-2,4,6- 0.61 g of 3, 5-triallyl-1,3,5-trizaine-2,4,6-trione (TTT) and 0.03 g of irgacure 754 are mixed to prepare a monomer mixture. The monomer mixture is defoamed in vacuo.

An organic additive was added to the semiconductor nanocrystalline chloroform dispersion [concentration: (absorption at 449 nm) X (volume of QD solution (mL)) = 3.75] prepared in Reference Example as shown in the following Table 1 2 and 3, Production Examples 1 and 2) to obtain a mixed solution. The semiconductor nanocrystal solution is prepared as it is (Comparative Preparation Example 1) or the above-mentioned mixed solution, mixed with the monomer mixture (1.5 g) prepared above and vortexed to obtain a semiconductor nanocrystal composition as shown in Table 1 below . The obtained composition was vacuum-dried at room temperature for 1 hour to remove chloroform contained in the composition.

Sample Types of organic additives Amount of organic additive (based on total weight of monomer mixture) Comparative Preparation Example 1 None (X) - Comparative Production Example 2 ODE (octadecene) 0.5 wt% Comparative Production Example 3 TEA (triethylamine) 2.5 wt% Production Example 1 TOA (trioctylamine) 0.1 wt% Production Example 2 TOP (trioctylphosphine) 2.5 wt%

Example  1 to 2 and Comparative Example  1 to 3

1 g of each of the semiconductor nanocrystal compositions obtained in Comparative Production Examples 1 to 3 and Production Examples 1 and 2 was drop cast on a PET film on which a barrier was sputtered. The barrier is SiOx (0 < x < 2, I-component Co., Ltd.). The composition was covered with a PET film and cured by UV for 4 minutes (light intensity: 100 mW / cm ² ) to obtain a semiconductor nanocrystal-polymer composite film having the structure shown in Fig.

Using a spectrophotometer (Konica Minolta, CM-3600d), the haze of a semiconductor nanocrystal-polymer composite film prepared by the following method is measured:

First, when the light is irradiated into the integrating sphere and all the light is collected, the light amount (T1) is measured. When the light is transmitted through the straight line, the amount of light (T2) is measured. Then, the semiconductor nanocrystal-polymer composite film is placed at the entrance of the integrating sphere, light is irradiated into the integrating sphere, and the light amount (T3) when all the light is collected and the black plate placed in the linear direction of the incident light, The light amount T4 when the light is excluded is measured (T4 / T3 - T2 / T1) and X 100 (%) is expressed as haze.

The semiconductor nanocrystal-polymer composite film was inserted between a light guide plate of a 60-inch TV having a blue LED having a peak wavelength of 449 nm and an optical film (i.e., a prism sheet, a micro lens sheet, and a brightness enhancement film) Measure the luminance (relative luminance) with a spectroradiometer (Konica minolta, CS-2000) in front of about 30 cm. The brightness is a relative value to a reference semiconductor nanocrystal-polymer composite film (reference film).

The haze and luminance measurement results are shown in Table 2 below and in FIG. 3 and FIG.

Sample Haze (%) Relative luminance of film (%) Comparative Example 1 21.0 40 Comparative Example 2 19.2 33 Comparative Example 3 28.4 45 Example 1 50.2 94 Example 2 93.3 94

It is confirmed that the scattering increases and the haze value increases significantly (200% or more, more preferably 400% or more) and the luminance increases remarkably (200% or more) in Examples 1 and 2.

Manufacturing example  3 to Manufacturing example  6: Preparation of semiconductor nanocrystal compositions II

0.37% by weight of oleylamine (Production Example 3), 0.18% by weight of octylamine (Production Example 4), 0.34% by weight of dioctylamine (Preparation Example 5) and 0.34% by weight of trioctylphosphine oxide 6) was used in an amount of 2.5% by weight, a semiconductor nanocrystal composition was prepared in the same manner as in Production Example 1.

Example  3 to 6

A semiconductor nanocrystal-polymer composite film was prepared in the same manner as in Example 1 except that the semiconductor nanocrystal compositions of Production Examples 3 to 6 were used, and the luminance was measured for each film. The results are shown in Fig. 5 and Table 3.

Organic additive (content) Hayes  Value (%) Brightness (%) Example  3 Oleylamine (0.37 wt%) 64.7 76 Example  4 Octylamine (0.18 wt) 74.9 79 Example  5 Dioctylamine (0.34 wt) - 84 Example  6 Trioctylphosphine oxide (2.5 wt%) 87.8 84

5 and Table 3 confirm that the luminance of the semiconductor nanocrystal-polymer composite film produced by the addition of the organic additive can be improved by about two times or more.

Example  7: Change of luminance according to addition amount of organic additive

Except that a semiconductor nanocrystal composition containing trioctylamine (TOA) or trioctylphosphine (TOP) as shown in Table 4 below was used, respectively, in the same manner as in Example 1 or Example 2 A semiconductor nanocrystal-polymer composite film is prepared, and haze and luminance are measured for each of the produced films. The results are shown in Fig. 6 and Table 4.

Organic additive (content) Hayes  Value (%) Brightness (%) Example  7 TOA 0.5 wt% 50.9 88 TOA 2.5 wt% 94.5 91 TOA 5 wt% 95.5 91 TOP 1 wt% 90.6 69 TOP 5 wt% 95.0 88

From the results of FIG. 6 and Table 4, it is confirmed that the haze value and the luminance of the film are increased by the addition of the organic substance.

Example  8: Reliability evaluation

The excess organic material removal process was carried out once or twice and the semiconductor nanocrystals were used, and 0.5 wt% of trioctylamine (TOA), 5 wt% of trioctylphosphine (TOP), 10 wt% of trioctylphosphine (TOP) %, The reliability was tested for driving the backlight unit in the following manner: &lt; tb &gt; &lt; TABLE &gt;

The semiconductor nanocrystal-polymer composite film was inserted between a light guide plate of a 40-inch TV equipped with a blue LED having a peak wavelength of 449 nm and an optical film (prism sheet, microlens, brightness enhancement film) The luminance is measured with a spectro radometer (Konica minolta, CS-2000). In a 50 degree high temperature drive chamber, the brightness is measured over time to compare the change in brightness.

The results are shown in Fig. From Fig. 7, it is confirmed that the semiconductor nanocrystal-polymer composite film of the embodiment has excellent stability (as well as high luminance).

compare Manufacturing example  4 to 5 and Manufacturing example  7: Fabrication of semiconductor nanocrystal composition

30 parts by weight of lauryl methacrylate (monomer), 36 parts by weight of tricyclodecane dimethanol diacrylate (monomer), 4 parts by weight of trimethylol propane triacrylate (monomer) And 20 parts by weight of an epoxy diacrylate oligomer (manufactured by Satomer, oligomer) were mixed to obtain a monomer / oligomer mixture, and 1-hydroxy-cyclohexyl- phenyl-ketone) and 1 part by weight of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide to prepare a final mixture. The final mixture is degassed in vacuo.

In the same manner as described in the Reference Example, the semiconductor nanocrystals are centrifuged once. The toluene dispersion of the obtained semiconductor nanocrystals (concentration: (absorption at 449 nm) X (volume of QD solution (mL)) = 3.75) is again mixed with an excess of ethanol and centrifuged. The separated semiconductor nanocrystals were dispersed in 10 parts by weight of lauryl methacrylate (monomer), and then additives were added as shown in the following Table 5 (Comparative Preparation Example 5, Production Example 7) . The semiconductor nanocrystalline chloroform dispersion prepared in Reference Example was prepared as a mixture solution (Comparative Preparation Example 4) or as described above, and the resulting mixture was put into a final mixture containing 90 parts by weight of the monomer (oligomer) mixture, followed by vortexing, To obtain a nanocrystal composition.

Sample additive The amount of additive (per 100 parts by weight of total monomer and oligomer) Comparative Production Example 4 none - Comparative Preparation Example 5 Silica (purchased from Sigma-Aldrich) # 748161) 5 parts by weight Production Example 7 TOP (trioctylphosphine) 5 parts by weight

Example 9 and Comparative Examples 4 and 5 :

A semiconductor nanocrystal-polymer composite film was produced in the same manner as in Example 1, except that the semiconductor nanocrystal compositions of Production Example 7 and Comparative Production Examples 4 and 5 were used, and haze and luminance were measured for each film . The results are shown in Fig. 10 and Fig.

10 and 11, the film of Example 9 containing trioctylphosphine as an additive includes the film of Comparative Example 4 containing no additive and silica (having a difference in refractive index (RI) from epoxy resin) (81%) while having a much higher haze value (61.4%) than that of the film of Comparative Example 5, which has a significantly improved luminance value.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, And falls within the scope of the invention.

Claims (23)

Semiconductor nanocrystals; Organic additives; A semiconductor nanocrystal composition comprising at least one polymerizable substance selected from polymerizable monomers, polymerizable oligomers, and combinations thereof, wherein the semiconductor nanocrystal composition exhibits a haze of at least 40% after polymerization. The method according to claim 1,
Wherein the polymerizable component comprises a polymerizable monomer and a polymerizable oligomer. The method according to claim 1,
Wherein the semiconductor nanocrystals comprise Group II-VI compounds, Group III-V compounds, Group IV-VI compounds, Group IV elements or compounds, or combinations thereof. The method according to claim 1,
Wherein the semiconductor nanocrystals have a core shell structure. The method according to claim 1,
Wherein the semiconductor nanocrystals have a quantum efficiency of 50% or more. The method according to claim 1,
Wherein the semiconductor nanocrystals have a half-width of 45 nm or less. The method according to claim 1,
Wherein the semiconductor nanocrystals have a content of an organic substance surrounding the surface of the nanocrystals including a ligand compound, a solvent, or both, of 35% by weight or less based on the total weight of the semiconductor nanocrystals. The method according to claim 1,
The organic additive may include an amine having at least one C8 to C30 alkyl or alkenyl group, a phosphine having at least one C8 to C30 alkyl or alkenyl group, a phosphine oxide having at least one C8 to C30 alkyl or alkenyl group, Or a combination thereof. The method according to claim 1,
Wherein the organic additive comprises from 0.05% to 10% by weight, based on the total weight of the polymerizable component. The method according to claim 1,
The polymerizable monomer may be a mixture of a first monomer having at least two thiol (SH) groups at the ends thereof and a second monomer having at least two carbon-carbon unsaturated bonds at the ends thereof, an acrylate monomer, a methacrylate monomer, Urethane (meth) acrylate-based monomer, epoxy-based monomer, silicone-based monomer, or a combination thereof,
Wherein the polymerizable oligomer comprises an acrylate oligomer, a methacrylate oligomer, a urethane acrylate oligomer, an epoxy oligomer, a silicone oligomer, or a combination thereof. The method according to claim 1,
Wherein the semiconductor nanocrystal composition further comprises an inorganic oxide selected from silica, alumina, titania, zirconia, zinc oxide, and combinations thereof. Semiconductor nanocrystals; Organic additives; And a polymer of at least one polymerization component selected from a polymerizable monomer and a polymerizable oligomer, wherein the semiconductor nanocrystalline-polymer complex has a haze value of 40% or more. 13. The method of claim 12,
The composite is a film-like semiconductor nanocrystal-polymer composite. 13. The method of claim 12,
Wherein the semiconductor nanocrystals comprise Group II-VI compounds, Group III-V compounds, Group IV-VI compounds, Group IV elements or compounds, or combinations thereof. 13. The method of claim 12,
Wherein the semiconductor nanocrystals emit green light or red light. 13. The method of claim 12,
Further comprising an inorganic oxide selected from silica, alumina, titania, zirconia, zinc oxide, and combinations thereof. 13. The method of claim 12,
The organic additive may include an amine having at least one C8 to C30 alkyl or alkenyl group, a phosphine having at least one C8 to C30 alkyl or alkenyl group, a phosphine oxide having at least one C8 to C30 alkyl or alkenyl group, A combination thereof, a semiconductor nanocrystal-polymer composite. 13. The method of claim 12,
Wherein the organic additive is contained in an amount of 0.05% by weight to 10% by weight based on the total weight of the polymerizable monomer or the polymerizable monomer and the polymerizable oligomer. 13. The method of claim 12,
The polymerizable monomer may be a mixture of a first monomer having at least two thiol (SH) groups at the ends thereof and a second monomer having at least two carbon-carbon unsaturated bonds at the ends thereof, an acrylate monomer, a methacrylate monomer, Urethane (meth) acrylate monomers, epoxy-based monomers, silicone-based monomers, or combinations thereof,
The polymerizable oligomer may be an acrylate oligomer, a methacrylate oligomer, a urethane (meth) acrylate oligomer, an epoxy oligomer, a silicone oligomer, or a combination thereof. LED light source;
And a light switching layer provided so as to be spaced apart from the LED light source so as to convert light incident from the LED light source into white light,
Wherein the light conversion layer comprises the semiconductor nanocrystal-polymer composite of claim 12. 12. A backlight unit for a liquid crystal display device, comprising: 21. The method of claim 20,
Wherein the light conversion layer comprises: a film of the semiconductor nanocrystal-polymer composite; And at least one of a first polymer film and a second polymer film positioned on at least one side of the film,
Wherein the first polymer film and the second polymer film are made of a polyester, a cyclic olefin polymer (COP), a first monomer having at least two thiol (SH) groups at the terminal, and a second monomer having at least two carbon- And the second polymer comprises a polymer selected from the group consisting of a polymer obtained by polymerizing a second monomer and a polymer selected from a combination thereof. 22. The method of claim 21,
Wherein at least one of the first polymer film and the second polymer film further comprises an inorganic oxide. 22. The method of claim 21,
Wherein at least one of the first polymer film and the second polymer film has irregularities on a surface not in contact with the light conversion layer.

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