KR20230074938A - Luminescent dye dispersion photocurable cholesteric liquid crystal composition and luminescent dye dispersion optical film comprising the same - Google Patents

Abstract

The present invention relates to a luminescent dye-dispersed photocurable cholesteric liquid crystal composition containing a photocurable resin that forms a cholesteric liquid crystalline phase, and an optical film capable of improving light conversion efficiency by manufacturing using the liquid crystal composition. According to the present invention, the optical film manufactured by using the luminescent dye-dispersed photocurable cholesteric liquid crystal composition can realize high color reproduction without using expensive quantum dots.

Description

Luminescent dye dispersion photocurable cholesteric liquid crystal composition and luminescent dye dispersion optical film comprising the same}

The present invention provides a photocurable cholesteric liquid crystal composition containing a photocurable resin forming a cholesteric liquid crystal phase and a light-emitting dye dispersion capable of improving light conversion efficiency, wavelength and half width characteristics by including the liquid crystal composition. It is about optical film.

As society entered the information age in earnest, the display field, which processes and displays a large amount of information, has developed rapidly. Various flat panel display devices such as a panel device (PDP), a field emission display device (FED), and an organic light emitting diode display device (OLED) have been developed and are in the spotlight. Recently, development of next-generation displays such as a quantum-dot light emitting diode display device (QDLED) and a micro light emitting diode display device (μ-LED) has been actively pursued.

A liquid crystal display is currently one of the most widely used flat panel displays. The liquid crystal display may include field generating electrodes including a pixel electrode and a common electrode, and a liquid crystal layer formed between them. An image can be displayed by applying a voltage to the field generating electrodes to generate an electric field in the liquid crystal layer, thereby determining the alignment of liquid crystal molecules in the liquid crystal layer and controlling the polarization of incident light.

The liquid crystal display device uses color filters to form colors. When light emitted from the backlight unit passes through the red color filter, the green color filter, and the blue color filter, each color filter reduces the amount of light by about 1/2. 3, the light efficiency may be low.

In order to compensate for this decrease in light efficiency and to implement high color reproducibility, research has recently been conducted to use quantum dots in display devices.

Quantum dots emit light as electrons in an unstable state descend from the conduction band to the valence band. Quantum dots generate strong fluorescence because they have a very large extinction coefficient and excellent quantum yield. In addition, since the emission wavelength is changed according to the size of the quantum dots, light in the entire visible light range can be obtained by adjusting the size of the quantum dots.

In particular, a photo luminescent liquid crystal display (PL-LCD) replaces a color filter used in a conventional liquid crystal display with a quantum dot color conversion layer (QD-CCL). It is a liquid crystal display device. PL-LCD can display color images using visible light generated when low-wavelength light, such as ultraviolet or blue light generated from a light source and controlled by a liquid crystal layer, is irradiated onto a color conversion layer (CCL). there is.

In addition, in next-generation displays such as Blue-OLED, QDLED, and μ-LED, the color conversion layer (CCL) is irradiated with visible light generated when active emission light in the low wavelength band, such as controlled ultraviolet or blue light, is irradiated. video can be displayed.

However, quantum dots are expensive and are easily damaged by moisture and/or oxygen, resulting in reduced luminous efficiency. Therefore, development of a low-cost, excellent color conversion composition and color conversion film that does not use quantum dots is required. The development of color conversion compositions and color conversion films using inexpensive molecular organic photoluminescent dyes (PL) has been attempted to replace expensive particulate quantum dots, but the light efficiency and wide range of organic photoluminescent (PL) dyes are unique. Due to the half width characteristic, the color reproducibility is low, and it is difficult to apply the color conversion film.

Korean Patent Publication No. 2008-0038703 Korean Patent Publication No. 2020-0049980

The present invention provides a light-emitting dye-dispersed photocurable cholesteric liquid crystal composition containing a photocurable resin that forms a cholesteric liquid crystal phase instead of using a conventional non-liquid crystalline photocurable resin, and the light conversion efficiency is improved by including the liquid crystal composition. It is intended to provide a luminescent dye dispersion optical film that can be improved.

In addition, since the present invention uses a photocurable resin that forms a cholesteric liquid crystal phase, high light conversion efficiency can be achieved without using light scattering particles, which are required in the prior art. It is intended to provide a light-emitting dye-dispersed photocurable cholesteric liquid crystal composition having excellent thin film formation processability.

In order to solve the above problems,

In one embodiment, the present invention comprises a cholesteric liquid crystal mixture consisting of a reactive liquid crystal monomer and a chiral dopant having a photoactive group; a luminescent dye dispersed in the cholesteric liquid crystal mixture; And, it provides a light-emitting dye-dispersed photocurable cholesteric liquid crystal composition comprising a photoinitiator.

The cholesteric liquid crystal mixture may be a material represented by Structural Formula 1 below:

[Structural Formula 1]

In Structural Formula 1,

R ₁ is P ₁ -(CH ₂ ) _m1 O-, P ₁ -(CH ₂ ) _m1 -, P ₁ -(CH ₂ ) _m1 COO- or P ₁ -(CH ₂ ) _m1 OOC-;

R ₂ is P ₂ -(CH ₂ ) _m2 O-, P ₂ -(CH ₂ ) _m2 -, P ₂ -(CH ₂ ) _m2 COO- or P ₂ -(CH ₂ ) _m2 OOC-;

wherein m1 and m2 are each independently an integer of 0 to 12;

P1 and P2 are each independently a hydrogen group, an acryl group, a methacryl group, an acryl amide group, or a methacryl amide group,

X ₁ and X ₂ are each independently a linking group connecting C _A , C _B and C _C , a single bond, a double bond (C=C), a triple bond (C≡-O-CO- or -CO-O- An ester group selected from -CO-, -O-, -CH ₂ -, -CH ₂ O-, -CF ₂ -, -CF ₂ O-, -CH ₂ CH ₂ -, -CH ₂ CH ₂ O- , -CF ₂ CH ₂ -, -CF ₂ CF ₂ -, -CO-C=C-, one linking group selected from -O-CO-C=C-,

n and m are each independently an integer from 0 to 2;

CA, CB, and Cc are each independently a cyclic group selected from aryl, heteroaryl, or C ₄ to C ₁₀ cycloalkyl groups, and a linear rigid-core group through the linking group X Forming a, one or more hydrogen atoms in each ring group may be unsubstituted or substituted with a C ₁ to C ₂ alkyl group, a C ₁ fluorinated carbon group or a halogen group,

The aryl group is a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, or a dibenzothiophene group (dibenzothiophenyl), the heteroaryl group is a pyridine group, a pyrimidine group, a pyrazine group, or a quinoline group, and the cycloalkyl group is a cyclobutane group ( cyclobutane, cyclohexane, bicyclic cyclohexane, bicyclic cyclopentane, or cholesterol, and heterocycloalkyl is tetrahydropyran group (tetrahydropyran), or dioxin group (dioxane).

The compound represented by Structural Formula 1 may be one or more selected from the group consisting of compounds represented by Formulas 2 to 15 below:

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

The chiral dopant having a photoactive group may be at least one selected from the group consisting of compounds represented by Chemical Formulas 16 to 21 below:

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

The luminescent dye may be one or more selected from the group consisting of Formulas 22 to 27 below:

[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

The liquid crystal composition may be in a form in which a luminescent dye is dispersed in a one-dimensional photonic band gap structure after photocuring.

In addition, in one embodiment, the present invention provides a luminescent dye-dispersed optical film comprising the luminescent dye-dispersed photocurable cholesteric liquid crystal composition.

The light-emitting dye-dispersed optical film may include a thin film having a planar array structure or a focal conic array structure by photocuring the liquid crystal composition.

The luminescent dye-dispersed optical film may control a resonance emission wavelength of the luminescent dye by adjusting a one-dimensional photonic bandgap.

The luminescent dye-dispersed optical film may be one in which emission of the luminescent dye is circularly polarized by controlling a chiral photonic bandgap.

The light-emitting dye-dispersed optical film may include a thin film form obtained by photolithography or inkjet printing by converting the liquid crystal composition into photoresist (PR) or ink (Ink).

In addition, the present invention, in one embodiment, provides a color conversion technology-based information display device including the light-emitting dye dispersed optical film.

The luminescent dye-dispersed photocurable cholesteric liquid crystal composition according to the present invention uses a photocurable resin and a low-cost dye that form a photonic bandgap structure by a cholesteric liquid crystal phase instead of using a conventional non-liquid crystalline photocurable resin. By using, the optical film prepared using the light-emitting dye-dispersed photocurable cholesteric liquid crystal composition can realize a high color gamut without using expensive quantum dots, excellent light conversion efficiency, narrow half-width characteristics, light emission wavelength modulation and Circularly polarized light emission is possible.

In addition, the luminescent dye-dispersed photocurable cholesteric liquid crystal composition according to the present invention can achieve high light conversion efficiency without using a large amount of light scattering particles, which are essentially required in the prior art. Therefore, in manufacturing a color conversion optical film using photolithography and inkjet printing, it is possible to provide a dye-dispersed photocurable resin composition having excellent thin filming processability.

1 is a schematic diagram of a luminescent dye-dispersed color conversion optical film according to the present invention: (a) a color conversion optical film in which a dye is dispersed in a photoisotropic polymer matrix of the prior art, (b) a one-dimensional photonic band presented in the present invention An optical film in which dyes are dispersed in a polymer matrix having a gap (PBG) structure (planar array state) and (c) an optical film in which dyes are dispersed in a polymer matrix having a one-dimensional photonic bandgap (PBG) structure proposed in the present invention film (in the focal configuration).
2 is an optical micrograph and visible light transmission spectrum of optical films CLC20, CLC22, CLC24, CLC26, CLC28 and HDDA films prepared from the photocurable cholesteric liquid crystal composition according to the present invention.
Figure 3 is the photoluminescence of the dye-dispersed optical films CLC20, CLC22, CLC24, CLC26, CLC28 prepared from the photocurable cholesteric liquid crystal composition according to the present invention, and the nematic liquid crystal (MLC) and HDDA films to which no chiral dopant is added. spectrum (excitation light wavelength = 360 nm).
4 shows PBG characteristics and PL characteristics of an optical film made from a cholesteric liquid crystal mixture CLC25 composition according to the present invention.
5 shows PBG characteristics and PL characteristics according to circularly polarized light excitation of an optical film made from a cholesteric liquid crystal mixture CLC25 composition according to the present invention.
6 is a change in PL spectrum according to the wavelength of circularly polarized excitation light of an optical film made from a composition of cholesteric liquid crystal mixture CLC25 according to the present invention.
Figure 7 is the optical and spectroscopic characteristics of the luminescent dye and the optical film according to Example 2 of the present invention: (a) absorption and PL spectrum of the dye in ethanol solution, (b) dye dispersion CLC and HDDA under 365 nm ultraviolet irradiation Comparison of dye emission spectra in focal, planar configuration, and HDDA films of films and (c) photocurable CLC films.
Figure 8 is the spectroscopic characteristics of the luminescent dye and the optical film according to Example 2 of the present invention: (a) absorption characteristics and PBG characteristics of compositions A, B, and C, (b) PL of the dye according to the dye dispersion matrix Characteristic comparison.
9 shows absorption and PBG characteristics of a film according to Example 2 of the present invention and circular polarization dependent characteristics of an optical film according thereto: (a) absorption and PBG characteristics of a film (B), (b) circular polarization of an optical film PL characteristics.
Figure 10 is a spectroscopic characteristic of a luminescent dye and an optical film according to Example 3 of the present invention: (a) PBG characteristics of an optical film made from a photocurable cholesteric liquid crystal (CLC) composition, (b) dye dispersion matrix HDDA and comparison of PL characteristics of dyes according to CLC PBG.
11 is a light absorption and photoluminescence (PL) spectrum of a chloroform solution of a luminescent dye according to Example 4 of the present invention.
12 shows spectroscopic properties of a PBG film and a dye-dispersed optical film according to Example 4 of the present invention: (a) comparison of PBG properties of optical films prepared from photocurable cholesteric liquid crystal compositions CLC1 and CLC2, (b) Comparison of PL properties of dyes dispersed in PBG films of different properties.
13 shows spectroscopic characteristics of a PBG film and a dye-dispersed optical film according to Example 4 of the present invention: (a) PBG characteristics of an optical film prepared from a photocurable cholesteric liquid crystal composition CLC1, (b) the CLC1 PBG PL characteristics for left circular polarization (LCP) and right circular polarization (RCP) of a dye dispersed in a film.
Figure 14 is the optical and spectroscopic characteristics of the luminescent dye and the optical film according to Example 5 of the present invention: (a) absorption and PL spectrum of the dye in methanol solution, (b) dye dispersion CLC and HDDA under 365 nm UV irradiation Comparison of Dye Emission Spectra in Planar Configuration and HDDA Films of Film and (c) Photocured CLC Film.
15 shows spectroscopic characteristics of a PBG film and PL characteristics of a disperse dye according to Example 5 of the present invention: (a) transmission spectrum of the PBG film, (b) reflection spectrum of the PBG film, (c) left circular polarization (LCP) ) and changes in PL characteristics of dyes for right circular polarization (RCP) excitation light.

Since the present invention can make various changes and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description.

However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In the present invention, the term "comprises" or "has" is intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

In the present invention, a cholesteric liquid crystal or a chiral nematic liquid crystal is induced by adding a chiral agent to a nematic liquid crystal and has a helical structure of a certain period. A cholesteric liquid crystal in a planar state in which the spiral axis is perpendicular to the substrate reflects the circularly polarized light component coincident with the twist direction of the spiral among the light incident parallel to the spiral axis, and the circularly polarized light component in the other direction is reflected. It means a liquid crystal having selective reflection characteristics that transmit.

The luminescent dye-dispersed photocurable cholesteric liquid crystal composition according to the present invention uses a photocurable resin that forms a cholesteric liquid crystal phase and a low-cost dye instead of a conventional non-liquid crystalline photocurable resin, thereby producing the liquid crystal composition. The included optical film can realize a high color gamut without using expensive quantum dots, and has excellent light conversion efficiency, narrow half-width characteristics, and emission wavelength modulation.

Hereinafter, the present invention will be described in detail.

The present invention is a cholesteric liquid crystal mixture consisting of a reactive liquid crystal monomer and a chiral dopant having a photoactive group; a luminescent dye dispersed in the cholesteric liquid crystal mixture; And, it provides a light-emitting dye-dispersed photocurable cholesteric liquid crystal composition comprising a photoinitiator.

The liquid crystal composition may include a photocurable composition that expresses a cholesteric liquid crystal phase instead of a non-liquid crystalline photocurable monomer used in the prior art. In addition, a low-cost luminescent dye may be included instead of the high-cost quantum dots.

The liquid crystal composition may be in a form in which a dye is dispersed in a one-dimensional photonic band gap structure after photocuring.

While the conventional photocurable resin composition using quantum dots has a photoisotropic structure, the light-emitting dye-dispersed photocurable cholesteric liquid crystal composition according to the present invention forms a one-dimensional photonic bandgap structure to increase luminous efficiency and improve luminous properties. can be modified and enhanced.

The cholesteric liquid crystal mixture composed of the reactive liquid crystal monomer and a chiral dopant having a photoactive group may be a material represented by Structural Formula 1 below:

[Structural Formula 1]

In Structural Formula 1,

R ₁ is P ₁ -(CH ₂ ) _m1 O-, P ₁ -(CH ₂ ) _m1 -, P ₁ -(CH ₂ ) _m1 COO- or P ₁ -(CH ₂ ) _m1 OOC-;

R ₂ is P ₂ -(CH ₂ ) _m2 O-, P ₂ -(CH ₂ ) _m2 -, P ₂ -(CH ₂ ) _m2 COO- or P ₂ -(CH ₂ ) _m2 OOC-;

wherein m1 and m2 are each independently an integer of 0 to 12;

P1 and P2 are each independently a hydrogen group, an acryl group, a methacryl group, an acryl amide group, or a methacryl amide group,

X ₁ and X ₂ are each independently a linking group connecting C _A , C _B and C _C , a single bond, a double bond (C=C), a triple bond (C≡-O-CO- or -CO-O- An ester group selected from -CO-, -O-, -CH ₂ -, -CH ₂ O-, -CF ₂ -, -CF ₂ O-, -CH ₂ CH ₂ -, -CH ₂ CH ₂ O- , -CF ₂ CH ₂ -, -CF ₂ CF ₂ -, -CO-C=C-, one linking group selected from -O-CO-C=C-,

n and m are each independently an integer from 0 to 2;

CA, CB, and Cc are each independently a cyclic group selected from aryl, heteroaryl, or C ₄ to C ₁₀ cycloalkyl groups, and a linear rigid-core group through the linking group X Forming a, one or more hydrogen atoms in each ring group may be unsubstituted or substituted with a C ₁ to C ₂ alkyl group, a C ₁ fluorinated carbon group or a halogen group,

The aryl group is a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, or a dibenzothiophene group (dibenzothiophenyl), the heteroaryl group is a pyridine group, a pyrimidine group, a pyrazine group, or a quinoline group, and the cycloalkyl group is a cyclobutane group ( cyclobutane, cyclohexane, bicyclic cyclohexane, bicyclic cyclopentane, or cholesterol, and heterocycloalkyl is tetrahydropyran group (tetrahydropyran), or dioxin group (dioxane).

The compound represented by Structural Formula 1 may be one or more selected from the group consisting of compounds represented by Formulas 2 to 15 below:

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

The chiral dopant having a photoactive group may be at least one selected from the group consisting of compounds represented by Chemical Formulas 16 to 21 below:

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

The luminescent dye may be at least one selected from the group consisting of Formulas 22 to 27 below, and may or may not contain a photopolymerizable group:

[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

The liquid crystal composition according to the present invention can be used as a low-cost, very excellent photoresist composition for color conversion and an ink composition for color conversion.

In addition, the present invention provides a luminescent dye-dispersed optical film comprising the luminescent dye-dispersed photocurable cholesteric liquid crystal composition.

1 shows a schematic diagram of an optical film (luminescent dye-dispersed color conversion optical film) comprising a liquid crystal composition according to the present invention: (a) a color conversion optical film in which dyes are dispersed in a photoisotropic polymer matrix of the prior art, (b) ) Optical film in which dyes are dispersed in a polymer matrix having a one-dimensional photonic bandgap (PBG) structure proposed in the present invention (planar array state) and (c) one-dimensional photonic bandgap (PBG) proposed in the present invention An optical film in which dyes are dispersed in a structured polymer matrix (fochalconic arrangement).

Conventional optical films have been used by photopolymerizing a mixture of quantum dots (QDs), acrylic monomers, and light scattering particles (TiO2) to form a film. There is a problem that the fairness of thinning through this is greatly reduced.

Therefore, the present invention can provide an optical film capable of realizing a high color gamut without using expensive quantum dots (QDs), and can realize high light conversion efficiency without using light scattering particles, thereby greatly reducing manufacturing cost and thinning process. can be improved

The light-emitting dye-dispersed optical film may improve light conversion efficiency of the optical film by including a liquid crystal composition including a photocurable resin forming a cholesteric liquid crystal phase.

In addition, the present invention has the characteristic of being able to tune (tuning) the emission wavelength that does not appear in the conventional quantum dot film.

The light-emitting dye-dispersed optical film may include a thin film having a planar array structure or a focal conic array structure by photocuring the liquid crystal composition.

The light-emitting dye-dispersed optical film may include a thin film form obtained by photolithography or inkjet printing by converting the liquid crystal composition into photoresist (PR) or ink (Ink).

The liquid crystal composition forms a one-dimensional photonic band gap structure after photocuring, and may have a form in which a luminescent dye is dispersed therein, thereby increasing luminous efficiency by forming the one-dimensional photonic band gap structure. can

The luminescent dye-dispersed optical film may control a resonance emission wavelength of the luminescent dye by adjusting a one-dimensional photonic bandgap.

The luminescent dye-dispersed optical film may be one in which emission of the luminescent dye is circularly polarized by controlling a chiral photonic bandgap.

A resonance phenomenon may appear due to the photonic bandgap characteristics of the optical film, and thus, the emission wavelength may be tuned, and the emission wavelength and half width of the luminescent dye inherent in the luminescent dye may be controlled using the luminescence caused by the resonance phenomenon. can do. The optical film may cause light emission of the luminescent dye to be circularly polarized using a resonance phenomenon due to photonic bandgap characteristics.

The optical film may be obtained by modulating the wavelength of light emitted by the luminescent dye in the range of 400 nm to 700 nm using a photonic bandgap structure of the film, and the optical film may have an emission half width of 15 to 60 nm. can

In addition, since the optical film emits light by converting the light emission spectrum of a wide half-width of a conventional light-emitting dye into a resonance spectrum having a narrow half-width without using quantum dots, it is possible to realize a high color reproduction rate.

That is, the present invention uses a low-cost luminescent dye instead of a color conversion film (QDEF) and a color filter (QDCF) using QDs to provide an optical film capable of excellent light conversion efficiency, narrow half-width characteristics, and light emission wavelength modulation. .

In addition, the present invention provides a color conversion technology-based information display device including the light-emitting dye dispersion optical film.

Hereinafter, the present invention will be described in more detail through examples and the like according to the present invention, but the scope of the present invention is not limited by the examples presented below.

[Example]

Preparation Example 1: Preparation of photopolymerizable monomer and chiral dopant

The photopolymerizable liquid crystal monomer, chiral dopant, and luminescent dye used in this embodiment are shown in Table 1, Table 2, and Table 3, respectively.

Preparation Example 2: Preparation of luminescent dye-dispersed photocurable resin composition and optical film

Dye compositions dispersed in various photocurable resin media were prepared using the photoluminescent dyes shown in Table 3. The prepared composition was formed into an optical film and the emission characteristics of the dyes were compared in the following experimental examples.

A. Luminescent dye sample dispersed in an isotropic medium

After evenly dissolving 0.05 to 5.0 wt.% of dye in chloroform, methanol, or 1,6-hexanediol diacrylate (HDDA), it is injected between two glass substrates maintained at a distance of 10 μm, and the excitation wavelength Emission characteristics were observed according to (excitation wavelength).

In addition, in order to compare the luminescence intensity according to the filmed polymer dispersion medium, 0.05 to 5.0 wt% of the dye was dispersed in HDDA (hexanediol diacrylate), and then the liquid sample was injected between two glass substrates maintained at a distance of 10 μm. And it was cured with 350 ~ 400nm ultraviolet light to prepare a solid filmed sample.

B. Luminescent dye sample dispersed in the solidified cholesteric liquid crystal film

As shown in the following examples, a uniform cholesteric liquid crystal composition was prepared by mixing photopolymerizable liquid crystal molecules and a chiral dopant. After preparing a uniform composition by mixing a specific ratio of luminescent dye here, 1.0 wt% of a photoinitiator was added to complete a photocurable resin composition having a cholesteric liquid crystal phase. As a photoinitiator, Ciba's Irgacure 651 (2,2-Dimethoxy-2-phenylacetophenone) was used.

The pitch of the one-dimensional photonic band gap (PBG) according to the structure of the cholesteric liquid crystal phase was adjusted by changing the amount of the chiral dopant added.

The prepared photocurable composition is injected between two glass substrates maintained at a distance of 10 μm, and the cholesteric rotation axis is arranged perpendicular to the substrate (Planar arrangement) or the cholesteric helix is randomly arranged (focalconic arrangement). ) was irradiated with 350 to 400 nm ultraviolet light to form a solid film.

Experimental Example 1

A photocurable resin composition and an optical film forming a one-dimensional photonic bandgap of various pitches were prepared and their properties were evaluated. After preparing a nematic liquid crystal mixture by mixing the reactive liquid crystal compounds 1-1, 1-2, and 1-3 of Table 1 in (25:25:50) weight percent (wt.%), the nematic liquid crystal mixture CLC20, CLC22, CLC24, CLC26, and CLC28, which are cholesteric liquid crystal mixtures, were prepared by adding 20, 22, 24, 26, and 28 wt.% of chiral dopant S811 (Formula 2-2) in Table 2, respectively. After adding the dye DATB (0.1 wt%) and 1.0 wt.% of a photoinitiator of Chemical Formula 3-1 in Table 3 to each mixture, they were mixed uniformly. Using the prepared dye-dispersed photocurable resin composition, a solidified optical film was prepared as described above and its properties were evaluated.

Optical micrographs and visible light transmission characteristics of the optical film are shown in FIG. 2 . The purple to red images on the top represent the selective reflection color of each optical film. It can be seen that the visible light transmission spectrum at the bottom also spectroscopically well represents the selective reflection region of the manufactured optical film. This indicates that the pitch of the one-dimensional photonic bandgap (PBG) according to the structure of the cholesteric liquid crystal phase can be adjusted by changing the addition amount of the chiral dopant, and as the addition amount of the chiral dopant increases, the selective reflection wavelength It can be seen that this shifts to a short wavelength. That is, the pitch of the one-dimensional photonic band gap (PBG) formed in the optical film changes in the direction of decreasing.

FIG. 3 shows a spectrum (PL Spectrum) of light emitted when the same concentration of the luminescent dye BPC3 is dispersed in different media. The wavelength of excitation light was 360 nm. While PL intensity is weak in the conventional photoisotropic polymer medium and achiral nematic liquid crystal medium, the light emission of an optical film using a photocurable polymer as a matrix made from a cholesteric liquid crystal phase containing a chiral dopant It can be seen that the intensity has increased significantly. It can be seen that there is a difference in light emission intensity according to the content of the chiral dopant, that is, the pitch of the one-dimensional photonic band gap (PBG). Therefore, it can be seen that the luminescence intensity of the dye depends on the PBG structure, and exhibits very excellent luminescence characteristics compared to conventional photoisotropic media without a PBG structure.

FIG. 4 shows the characteristics of an optical film made from a CLC25 composition prepared by using 25 weight percent of a chiral dopant in the cholesteric liquid crystal mixture as compared to that of an achiral nematic liquid crystal film. The wavelength of excitation light was 360 nm. In the case of the dye-dispersed CLC film, it was found that the PL intensity was remarkably improved compared to the LC film containing no chiral dopant. Therefore, it can be seen that the PBG structure induced by the addition of a chiral dopant plays an important role in improving the PL characteristics.

5 shows polarization-dependent characteristics of excitation light of an optical film made from a CLC25 composition prepared by using 25 weight percent of a chiral dopant in the cholesteric liquid crystal mixture. As the excitation light, Left Circularly Polarized (LCP) or Right Circularly Polarized (RCP) circular polarization with a wavelength of 360 nm was used. As shown in FIG. 5, when the polarization of the excitation light was the same as the polarization state of the selectively reflected light of the CLC25 film, stronger emission characteristics were exhibited (Ext with LCP, FIG. 5). On the other hand, when the polarization of the excitation light was opposite to the polarization state of the selectively reflected light of the CLC25 film, relatively weak emission characteristics were exhibited (Ext with RCP, FIG. 5). In addition, it was confirmed that the circular polarization characteristics of PL were the same as in FIG. 5 by using the left circular polarizer and the right circular polarizer as analyzers. In addition, the emission half-maximum width (FWHM) is ~35 nm, which is significantly reduced compared to unpolarized excitation and emission half-maximum widths (FWHM = 55-60 nm). Therefore, the dye-dispersed optical film prepared from the cholesteric liquid crystal mixture has polarization dependence, and when circularly polarized excitation light is used, a light emission spectrum in a circularly polarized state can be obtained, and a PL spectrum with a small half-width can be obtained. color purity can be improved. This is a unique phenomenon that has not been seen in conventional color conversion films, and is a phenomenon that occurs because the PBG structure formed by the cholesteric liquid crystal phase has optical chirality.

6 shows a change in the PL spectrum according to the wavelength of circularly polarized excitation light of an optical film made from a cholesteric liquid crystal mixture CLC25 composition. As shown in FIG. 6 , it can be seen that as the wavelength of the excitation light decreases from 360 nm to 330 nm, the full width at half maximum (FWHM) of the PL spectrum decreases from -36 nm to -19 nm. This is a significantly reduced value compared to the dye-specific luminescence half-width realized by the conventional method, and is new, which has not been implemented in the conventional color conversion film technology. Therefore, by manufacturing an optical film having a one-dimensional chiral PBG structure using the photopolymerizable cholesteric liquid crystal mixture, the color gamut of the color conversion film can be improved by significantly reducing the light emission half width.

Experimental Example 2

A photocurable resin composition and a dye-dispersed optical film forming a one-dimensional photonic bandgap of various pitches were prepared and their properties were evaluated. After preparing a nematic liquid crystal mixture by mixing the reactive liquid crystal compounds 1-1 and 1-4 of Table 1 in (50:50) weight percent (wt.%), the chiral liquid crystal mixture of Table 2 is prepared. Each cholesteric liquid crystal mixture was prepared by adding 16.0, 16.8, and 19.0 wt.% of dopant S811 (Formula 2-2). After adding the dye PM 597 (0.05 wt%) and 1.0 wt.% of a photoinitiator of Chemical Formula 3-3 in Table 3 to each mixture, they were uniformly mixed to prepare photocurable resin compositions A, B, and C. Using the prepared dye-dispersed photocurable resin composition, a solidified optical film was prepared as described above and its properties were evaluated.

7 shows the optical and spectroscopic properties of luminescent dyes and dye-dispersed optical films. Figure 7 (a) shows the absorption and PL spectrum of the dye PM 597 in an ethanol solution, and Figure 7 (b) shows the optical film in which the dye at the same concentration was dispersed in a polymer CLC film or a polymer HDDA film, respectively, under 365 nm UV irradiation. This is an observed picture. From this, the dye-dispersed CLC optical film (CLC, left) having a PBG structure provided by the present invention has a significantly higher luminous intensity (PL) than the conventional dye-dispersed optical film (HDDA, right) in which dye is dispersed in a photoisotropic polymer. intensity) can be seen.

FIG. 7(c) is a PL of a dye-dispersed CLC optical film prepared by photopolymerizing a photocurable CLC composition in a focal conic arrangement state and a planar arrangement state, respectively, and a conventional dye-dispersed optical film manufactured using a photoisotropic resin (HDDA). It is shown by comparing the characteristics. As shown in the comparative graph of FIG. 7(c), it can be seen that the dye-dispersed CLC optical film exhibits significantly improved photoluminescence intensity compared to the conventional dye-dispersed optical film. In addition, the dye-dispersed CLC optical film exhibits a characteristic in which the full width at half maximum is reduced by ~20% compared to the conventional HDDA optical film. In addition, in the case of the dye-dispersed CLC optical films of different arrangements, it can be seen that the films in the focal conic arrangement exhibit about twice as strong PL characteristics as the films in the planar arrangement.

8 shows spectroscopic characteristics of three types of CLC films and dye-dispersed optical films according to Example 2. The absorption characteristics and PBG characteristics of CLC films A, B, and C prepared from compositions A, B, and C are shown in FIG. 8(a). The PL characteristics of the PM 597 dye dispersed in the same ratio in each CLC film were compared with those of the conventional optical film (dye-dispersed HDDA film) and shown in FIG. 8(b). Through this, it can be seen that in the case of the CLC film, as in the above example, all three types exhibit much stronger PL than the conventional HDDA film. In addition, it can be seen that the spectroscopic characteristics of the dye-dispersed optical film vary greatly depending on the pitch of the PBG structure (that is, the component ratio of the chiral dopant) even in the case of a CLC film composed of the same components. In the case of Example 2, the PL characteristics of the dye-dispersed CLC optical film (composition B) containing 16.8 wt.% of the chiral dopant S811 (Formula 2-2) were the best.

Figure 9 (a) shows the dye absorption and PBG characteristics of the dye-dispersed CLC film according to the photocurable composition B of Example 2, and Figure 9 (b) shows the circularly polarized light PL characteristics of the dye-dispersed optical film according to this. As shown in FIG. 9(b), it can be seen that left or right circular polarized light with a full width at half maximum (FWHM) of 44.3 nm is emitted according to the polarization of the excitation light. This is ~33% reduced compared to the half width of 65.7 nm according to the conventional film, indicating that the emission half width of the dye can be reduced using the CLC film of the PBG structure provided in the present invention. Therefore, since the dye-dispersed CLC optical film provided in the present invention can induce PL with a narrow half-width by using inexpensive dyes instead of expensive quantum dots, it can be usefully used as a color conversion film for improving color reproducibility.

Experimental Example 3

A photocurable resin composition forming a one-dimensional photonic band gap of a specific pitch was prepared, and the characteristics of the dye-dispersed optical film made therefrom were evaluated. After preparing a nematic liquid crystal mixture by mixing the reactive liquid crystal compounds 1-1, 1-5, and 1-6 of Table 1 in a weight percent (wt.%) ratio of (50:25:25), the nematic liquid crystal mixture A cholesteric liquid crystal mixture having a specific PBG pitch was prepared by adding 23.0 wt.% of chiral dopant S811 (Formula 2-2) of Table 2 to the above. A photocurable resin composition was prepared by adding AMA (0.5 wt%) of the chemical formula 3-3 and 1.0 wt.% of a photoinitiator to the mixture thus prepared, and then mixing them uniformly. Using the prepared dye-dispersed photocurable resin composition, a solidified optical film was prepared as described above and its properties were evaluated.

10 shows a comparison between the spectroscopic characteristics of the luminescent dye and the CLC film according to Example 3 and the PL characteristics of the dye-dispersed CLC optical film and the dye-dispersed HDDA optical film prepared using the same. As shown in FIG. 10 (b), it can be seen that the CLC optical film having the PBG structure exhibits significantly stronger PL than the conventional HDDA optical film. Therefore, the dye-dispersed CLC optical film of the present invention can be usefully utilized to improve the color conversion efficiency of a color conversion film using a dye.

Experimental Example 4

A photocurable resin composition and an optical film forming a one-dimensional photonic bandgap of various pitches were prepared and their properties were evaluated. After preparing a nematic liquid crystal mixture by mixing the reactive liquid crystal compounds 1-1, 1-7, 1-8, and 1-9 of Table 1 in a weight percent (wt.%) of (30:30:30:10) , Two kinds of cholesteric liquid crystal mixtures CLC1 and CLC2 having different PBG pitches were prepared by adding 19.5 and 23.0 wt.% of chiral dopant S811 (Formula 2-2) of Table 2 to the nematic liquid crystal mixture, respectively. A photocurable resin composition was prepared by adding the dye BPC3 (0.5 wt%) of Chemical Formula 3-2 and 1.0 wt.% of a photoinitiator to each mixture and then mixing them uniformly. Using the prepared dye-dispersed photocurable resin composition, a solidified optical film was prepared as described above and its properties were evaluated.

11 shows light absorption and photoluminescence (PL) spectra of the luminescent dye according to Example 4 in a chloroform solution state. BPC3 dye shows a photoluminescence (PL) spectrum with an emission peak of 396.5 nm and an emission half-width of 50.8 nm in a chloroform solution.

12 shows a comparison of PBG characteristics of optical films prepared from the photocurable cholesteric liquid crystal compositions CLC1 and CLC2 and PL characteristics of dyes dispersed in PBG films having different characteristics. The PBG film exhibits a visible light spectrum with selective reflection peaks of 440 nm and 528 nm, respectively (FIG. 12a). The PL spectrum of the BPC3 dyes dispersed in the CLC1 and CLC2 films showed a photoluminescence peak of 396.5 nm and a full width at half maximum of 50.1 nm, but showed a large difference in photoluminescence intensity (FIG. 12b). Through this, in the case of a CLC film, even if it is a CLC film composed of the same components as in the above example, it can be seen that the spectroscopic characteristics of the dye-dispersed optical film vary greatly depending on the pitch of the PBG structure (ie, the component ratio of the chiral dopant). there is. In this example, the CLC1 film having PBG characteristics of 440 nm exhibited superior PL characteristics than the CLC2 film.

13 shows the spectroscopic characteristics of the PBG film and the dye-dispersed optical film according to Example 4. 13(a) shows the PBG characteristics of an optical film prepared from the photocurable cholesteric liquid crystal composition CLC1, and FIG. 13(b) shows the left circular polarization (LCP) and right circular polarization (RCP) of the dye dispersed in the CLC1 PBG film. The PL characteristics for each are shown. In this case, three types of unique phenomena differentiated from conventional dye-dispersed optical films can be found.

First, the dyes dispersed in the CLC1 PBG film have different PL characteristics depending on the left circular polarization (LCP) or right circular polarization (RCP) state of the excitation light. That is, when the polarization state of the excitation light is the same as the chirality (handedness) of the optically active CLC (ie, PBG), significantly stronger circularly polarized PL is emitted compared to the opposite case. At this time, the emitted light is circularly polarized. In the case of this embodiment, since the CLC PBG has a left-handed helix structure, as shown in FIG. 13(b), the left-handed polarization PL intensity for the LCP excitation light is strong. Conversely, the emission intensity of the right circularly polarized PL for the right circularly polarized excitation light is weak. Therefore, a specific circularly polarized PL can be induced using the circularly polarized excitation light.

Second, it can be seen that the emission wavelength is modulated. The ~396.5 nm photoluminescence peak inherent to the dye (Fig. 11b) was significantly shifted to 420 nm by the PBG CLC film (Fig. 13b). This is a unique phenomenon not found in conventional dye-dispersed optical films. This movement of the emission wavelength moves to a wavelength corresponding to the edge of PBG (ie, stopband, corresponding to 420 nm in the case of FIG. 13A), indicating that PL of a specific wavelength can be induced by adjusting the pitch of the PBG structure. That is, it means that the light emission wavelength can be controlled by using a polymer matrix containing a dye, which is very useful for the development of a color conversion optical film.

Third, the PL half width is very narrow, so the color purity is high. The dye-specific emission half-maximum width (FWHM) shown in FIG. 11(b) is about ~50.8 nm, but the emission half-maximum width of the dye-dispersed CLC optical film in FIG. 13(b) is only ~25.0 nm. This result is a value in which the dye-specific luminescence half width is reduced by about 50% by the optical film provided by the present invention, and corresponds to a value that is very difficult to achieve in a color conversion film using a dye. This means that the light emission half-width can be controlled using a polymer matrix containing the dye, rather than the dye-specific half-width, which means that it is very useful for the development of a high-purity color conversion optical film.

The three kinds of peculiar phenomena are very peculiar things not found in conventional color conversion optical films, and they originate from the one-dimensional PBG structure of cholesteric liquid crystal. In particular, it is caused by the resonance phenomenon of the optically active PBG structure according to the optical activity of CLC, and it enables modulation of PL wavelength by resonance, emission of circularly polarized PL, and emission of high-purity PL with a very small half width, thereby dye-dispersive color conversion. It can be used very usefully to improve the properties of the film.

Experimental Example 5

A photocurable resin composition and an optical film forming a one-dimensional photonic bandgap of various pitches were prepared and their properties were evaluated. After preparing a nematic liquid crystal mixture by mixing the reactive liquid crystal compounds 1-1, 1-7, 1-8, and 1-9 of Table 1 in a weight percent (wt.%) of (30:30:30:10) , 6 types of cholesteric liquid crystals having different PBG pitches by adding 19.8, 20.5, 22.0, 23.5, 24.5, and 25.5 wt.% of chiral dopant S811 (Formula 2-2) in Table 2 to the nematic liquid crystal mixture, respectively. A mixture was prepared. A photocurable resin composition was prepared by adding DCM (0.5 wt%) and 1.0 wt.% of a photoinitiator of Formula 3-5 of Table 3 to each mixture and then mixing them uniformly. Using the prepared dye-dispersed photocurable resin composition, a solidified optical film was prepared as described above and its properties were evaluated.

14 shows the optical and spectroscopic characteristics of the luminescent dye and the optical film according to Experimental Example 5. Figure 14 (a) shows the absorption and PL spectrum of the dye DCM in methanol solution, and Figure 14 (b) shows the optical film in which the same concentration of dye is dispersed in a photocurable CLC film or a photocurable HDDA film, respectively, irradiated with 365 nm ultraviolet rays. This is a picture taken from below. From this, the dye-dispersed CLC optical film (CLC, left) having a PBG structure provided by the present invention has a significantly higher luminous intensity (PL) than the conventional dye-dispersed optical film (HDDA, right) in which dye is dispersed in a photoisotropic polymer. intensity) can be seen.

14(c) shows a comparison between PL characteristics of a dye-dispersed CLC optical film prepared by photopolymerizing a photocurable CLC composition in a planar arrangement state and a conventional dye-dispersed optical film manufactured using a photoisotropic resin (HDDA). will be. As shown in the comparison graph of FIG. 14(c), it can be seen that the dye-dispersed CLC optical film exhibits significantly improved photoluminescence intensity compared to the conventional dye-dispersed optical film. In addition, the photoluminescence half-width was ~72.3 nm, which was reduced by about 18% compared to the DCM-specific half-width ~88.5 nm.

15 shows spectroscopic characteristics and PL characteristics of the dye-dispersed optical film according to Example 5. 15(a) is a light transmission spectrum of a dye-dispersed CLC film, 15(b) is a visible light reflection spectrum of a dye-dispersed CLC film, and 15(c) is a dye for left circularly polarized (LCP) and right circularly polarized (RCP) excitation light. It shows the PL characteristic change of each.

627 nm of the photoemission wavelength unique to the dye DCM (FIG. 14a) is indicated by a green line, and the stopband of the PBG CLC structure of 454 nm is indicated by a red line in FIG. 15(a), respectively. The visible light spectrum in FIG. 15(a) is due to the overlapping of dye absorption and selective reflection bands of CLC. Therefore, in order to find out the exact location of the selective reflection band of the CLC film, that is, PBG, the reflection spectrum of the CLC film was measured, which is shown in FIG. 15(b). Accordingly, the stopband (~454 nm) of the CLC film is indicated by a red dotted line.

As shown in FIG. 15(c), the dye-dispersed CLC optical film according to this embodiment exhibits the three kinds of peculiar phenomena described in Example 4 due to the resonance phenomenon according to the optically active PBG structure of the cholesteric liquid crystal. can be found This is differentiated from conventional dye-dispersed optical films, and PL wavelength modulation, circularly polarized light emission, and half-width reduction phenomena that do not appear in conventional dye-dispersed optical films can be found.

627 nm of the DCM dye's own photoemission wavelength (FIG. 14a) shifts to a shorter wavelength to 454 nm corresponding to the stopband of PBG due to the PBG characteristics and resonance of the CLC film. The dye-dispersed CLC optical film can emit circularly polarized light according to the polarization state of excitation light, and the optical film according to the present embodiment emits left circularly polarized light. In addition, the half-width at half maximum of the emitted circularly polarized PL is ~31.2 nm, which is about 65% reduced compared to the full width at half maximum of DCM-specific ~88.5 nm.

The above three kinds of phenomena as in Experimental Example 4 are very peculiar not found in conventional color conversion optical films, and they originate from the one-dimensional PBG structure of cholesteric liquid crystal. In particular, it is caused by the resonance phenomenon of the optically active PBG structure according to the optical activity of CLC, and it enables modulation of PL wavelength by resonance, emission of circularly polarized PL, and high color purity PL emission with a very small half width. Therefore, in the present invention, since the PL characteristics of the disperse dye can be adjusted by controlling the PBG structure of the CLC film, which is a dispersion medium of the dye, it provides a very useful means for improving the properties of the dye-dispersed color conversion film.

Claims (12)

a cholesteric liquid crystal mixture consisting of a reactive liquid crystal monomer and a chiral dopant having a photoactive group;
a luminescent dye dispersed in the cholesteric liquid crystal mixture; and,
A photocurable cholesteric liquid crystal composition comprising a photoinitiator dispersed in a luminescent dye.
According to claim 1,
The cholesteric liquid crystal mixture is a luminescent dye-dispersed photocurable cholesteric liquid crystal composition, characterized in that the material represented by the following structural formula (1):
[Structural Formula 1]

In Structural Formula 1,
R ₁ is P ₁ -(CH ₂ ) _m1 O-, P ₁ -(CH ₂ ) _m1 -, P ₁ -(CH ₂ ) _m1 COO- or P ₁ -(CH ₂ ) _m1 OOC-;
R ₂ is P ₂ -(CH ₂ ) _m2 O-, P ₂ -(CH ₂ ) _m2 -, P ₂ -(CH ₂ ) _m2 COO- or P ₂ -(CH ₂ ) _m2 OOC-;
wherein m1 and m2 are each independently an integer of 0 to 12;
P1 and P2 are each independently a hydrogen group, an acryl group, a methacryl group, an acryl amide group, or a methacryl amide group,
X ₁ and X ₂ are each independently a linking group connecting C _A , C _B and C _C , a single bond, a double bond (C=C), a triple bond (C≡-O-CO- or -CO-O- An ester group selected from -CO-, -O-, -CH ₂ -, -CH ₂ O-, -CF ₂ -, -CF ₂ O-, -CH ₂ CH ₂ -, -CH ₂ CH ₂ O- , -CF ₂ CH ₂ -, -CF ₂ CF ₂ -, -CO-C=C-, one linking group selected from -O-CO-C=C-,
n and m are each independently an integer from 0 to 2;
CA, CB, and Cc are each independently a cyclic group selected from aryl, heteroaryl, or C ₄ to C ₁₀ cycloalkyl groups, and a linear rigid-core group through the linking group X Forming a, one or more hydrogen atoms in each ring group may be unsubstituted or substituted with a C ₁ to C ₂ alkyl group, a C ₁ fluorinated carbon group or a halogen group,
The aryl group is a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a carbazolyl group, or a dibenzothiophene group (dibenzothiophenyl), the heteroaryl group is a pyridine group, a pyrimidine group, a pyrazine group, or a quinoline group, and the cycloalkyl group is a cyclobutane group ( cyclobutane, cyclohexane, bicyclic cyclohexane, bicyclic cyclopentane, or cholesterol, and heterocycloalkyl is tetrahydropyran group (tetrahydropyran), or dioxin group (dioxane).
According to claim 2,
A light-emitting dye-dispersed photocurable cholesteric liquid crystal composition, characterized in that the compound represented by Structural Formula 1 is at least one selected from the group consisting of compounds represented by Formulas 2 to 15:
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

According to claim 1,
The photoactive dye-dispersed photocurable cholesteric liquid crystal composition, characterized in that the chiral dopant having a photoactive group is at least one selected from the group consisting of compounds represented by the following formulas 16 to 21:
[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

According to claim 1,
The light-emitting dye-dispersed photocurable cholesteric liquid crystal composition, characterized in that the light-emitting dye is at least one selected from the group consisting of Formulas 22 to 27:
[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

According to claim 1,
The liquid crystal composition is a luminescent dye-dispersed photocurable cholesteric liquid crystal composition, characterized in that the luminescent dye is dispersed in a one-dimensional photonic band gap structure after photocuring.
A luminescent dye-dispersed optical film comprising the luminescent dye-dispersed photocurable cholesteric liquid crystal composition according to any one of claims 1 to 6.
According to claim 7,
A light-emitting dye dispersion optical film comprising a thin film form of a planar array structure or a focal conic array structure by photocuring the liquid crystal composition.
According to claim 7,
The luminescent dye-dispersed optical film is a luminescent dye-dispersed optical film, characterized in that for controlling the resonance emission wavelength of the luminescent dye by adjusting the one-dimensional photonic bandgap.
According to claim 7,
The luminescent dye-dispersed optical film is a luminescent dye-dispersed optical film, characterized in that the light emission of the luminescent dye is circularly polarized by adjusting the chiral photonic bandgap.
According to claim 7,
A light emitting dye dispersion optical film comprising a thin film form obtained by photolithography or inkjet printing by converting the liquid crystal composition into photoresist (PR) or ink (Ink).
An information display device based on color conversion technology comprising the luminescent dye-dispersed optical film of claim 7.

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