权利要求：
1. An electronic device, comprising:
a light source member configured to provide a first light;
a color conversion member disposed on the light source member and comprising a first conversion material that converts the first light into a second light and a second conversion material that converts the first light into a third light; and
a low-refractive index layer disposed on the light source member and disposed on at least one of upper and lower portions of the color conversion member,
wherein the low-refractive index layer comprises a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part, and a plurality of second voids defined by the matrix part,
wherein the plurality of hollow inorganic particles comprises a plurality of first voids and each first void is surrounded by a shell part,
wherein the first voids are unconnected from one another and the second voids are unconnected from one another, a total volume of the unconnected first voids is greater than a total volume of the unconnected second voids, and each second void is not surrounded by the shell part.
2. The electronic device of claim 1, wherein each of the hollow inorganic particles comprises a core part filled with air and the shell part surrounding the core part.
3. The electronic device of claim 2, wherein the shell part comprises at least one of SiO2, MgF2, or Fe3O4.
4. The electronic device of claim 1, wherein the second voids have sphere shapes and a mean diameter of about 1 nm to about 5 nm.
5. The electronic device of claim 1, wherein the hollow inorganic particles have sphere shapes and a mean diameter of about 20 nm to about 200 nm.
6. The electronic device of claim 1, wherein the matrix part comprises at least one of an acrylic-based polymer, a silicone-based polymer, a urethane-based polymer, or an imide-based polymer.
7. The electronic device of claim 1, wherein the low-refractive index layer has a transmittance of about 95% or more in a wavelength of about 400 nm to about 700 nm, and a refractive index of about 1.1 to about 1.5 in a wavelength of about 632 nm.
8. The electronic device of claim 1, wherein the first light is a blue light, the first conversion material is a first quantum dot that converts the blue light into a green light, and the second conversion material is a second quantum dot that converts the blue light into a red light.
9. The electronic device of claim 1, further comprising:
a display element disposed on the color conversion member.
10. The electronic device of claim 9, wherein the display element comprises a liquid crystal element.
11. The electronic device of claim 9, wherein the light source member comprises:
a guide panel; and
a light source disposed at one side of the guide panel,
wherein the low-refractive index layer is disposed between the guide panel and the color conversion member.
12. The electronic device of claim 11, wherein the low-refractive index layer is directly disposed on the guide panel.
13. The electronic device of claim 11, further comprising:
a barrier layer disposed on at least one of top and bottom surfaces of the color conversion member.
14. The electronic device of claim 1, wherein the color conversion member comprises a plurality of color conversion parts that are spaced apart from each other on a plane, wherein the color conversion parts comprise:
a first color conversion part comprising the first conversion material;
a second color conversion part comprising the second conversion material; and
a third color conversion part configured to transmit the first light.
15. The electronic device of claim 14, wherein the color conversion member further comprises a light blocking part disposed between the first to third color conversion parts spaced apart from each other.
16. The electronic device of claim 14, further comprising:
a reflection layer disposed on at least one of upper and lower portions of the color conversion parts,
wherein the reflection layer transmits the first light and reflects the second and third light.
17. The electronic device of claim 16, wherein the low-refractive index layer is disposed between the reflection layer and the color conversion parts and covers the color conversion parts.
18. The electronic device of claim 16, wherein the reflection layer is disposed between the low-refractive index layer and the color conversion parts and covers the color conversion parts.
19. The electronic device of claim 14, wherein the color conversion member further comprises a barrier layer disposed on at least one of upper and lower portions of the color conversion parts.
20. The electronic device of claim 19, wherein the barrier layer is disposed between the low-refractive index layer and the color conversion parts and covers the color conversion parts.
21. The electronic device of claim 14, wherein the color conversion member further comprises an optical filter layer configured to transmit at least one of the second and third light.
22. The electronic device of claim 21, wherein the optical filter layer comprises:
a first optical filter layer disposed on the first color conversion part; and
a second optical filter layer disposed on the second color conversion part.
23. The electronic device of claim 22, wherein the first optical filter layer transmits a green light, and the second optical filter layer transmits a red light.
24. The electronic device of claim 14, further comprising:
a first base substrate disposed on the light source member;
a second base substrate disposed on the light source member and facing the first base substrate; and
a liquid crystal layer disposed on the light source member between the first and second base substrates,
wherein the color conversion member is disposed between the liquid crystal layer and the second base substrate.
25. The electronic device of claim 24, wherein the low-refractive index layer is disposed between the liquid crystal layer and the color conversion member or between the color conversion member and the second base substrate.
26. The electronic device of claim 24, further comprising:
a first polarizing layer disposed between the light source member and the first base substrate or between the first base substrate and the liquid crystal layer; and
a second polarizing layer disposed between the liquid crystal layer and the second base substrate.
27. The electronic device of claim 14, wherein the light source member comprises an organic electroluminescent element.
28. The electronic device of claim 27, wherein the color conversion member further comprises a dam part that partitions the color conversion parts from each other and is disposed between adjacent color conversion parts of the color conversion parts.
29. The electronic device of claim 27, wherein the color conversion member further comprises a color filter layer disposed on the color conversion parts, and the color filter layer comprises:
a plurality of filter parts configured to emit light having various colors; and
a light blocking part configured to partition the filter parts from each other and disposed between adjacent filter parts of the filter parts.
30. An electronic device, comprising:
a light source member configured to provide a first light;
a color conversion member disposed on the light source member and comprising a first conversion material that converts the first light into a second light and a second conversion material that converts the first light into a third light; and
a low-refractive index layer disposed on the light source member and disposed on at least one of upper and lower portions of the color conversion member,
wherein the low-refractive index layer comprises a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part and comprising a plurality of first voids, and a plurality of second voids defined by the matrix part,
wherein a mean diameter of the first voids is greater than a mean diameter of the second voids,
wherein the first voids are unconnected from one another and the second voids are unconnected from one another, each first void is surrounded by a shell part, and each second void is not surrounded by the shell part.
31. An electronic device, comprising:
a display element;
a guide panel disposed below the display element;
a light source member disposed adjacent to at least one surface of the guide panel;
a color conversion member disposed between the guide panel and the display element; and
a low-refractive index layer disposed between the guide panel and the color conversion member,
wherein the low-refractive index layer comprises a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part, and a plurality of second voids defined by the matrix part,
wherein the plurality of hollow inorganic particles comprises a plurality of first voids, and each first void is surrounded by a shell part,
wherein the first voids are unconnected from one another and the second voids are unconnected from one another, a total volume of the unconnected first voids is greater than a total volume of the unconnected second voids, and each second void is not surrounded by the shell part.
32. The electronic device of claim 31, wherein the light source member comprises a light emitting element configured to emit a blue light, and
the color conversion member comprises a green quantum dot excited by the blue light to emit a green light, and a red quantum dot excited by at least one of the blue light and the green light to emit a red light.
33. The electronic device of claim 31, wherein each of the hollow inorganic particles comprises a core part filled with air and the shell part defining the core part, and
a mean diameter of the core parts is greater than a mean diameter of the second voids.
发明内容：
[0005]Exemplary embodiments of the present inventive concept provide an electronic device including a low-refractive index layer which includes hollow inorganic particles and void parts, which may improve strength while providing good low-refractive properties.
[0006]Exemplary embodiments of the present inventive concept also provide an electronic device in which a low-refractive index layer having high strength is provided on a display member, which may improve reliability and optical characteristics.
[0007]According to an exemplary embodiment, an electronic device includes a light source member configured to provide a first light, a color conversion member disposed on the light source member and including a first conversion material that converts the first light into a second light and a second conversion material that converts the first light into a third light, and a low-refractive index layer disposed on the light source member and disposed on at least one of upper and lower portions of the color conversion member. The low-refractive index layer includes a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part, and a plurality of void parts defined by the matrix part.
[0008]In an exemplary embodiment, each of the hollow inorganic particles includes a core part filled with air and a shell part surrounding the core part.
[0009]In an exemplary embodiment, the shell part includes at least one of SiO2, MgF2, or Fe3O4.
[0010]In an exemplary embodiment, the void parts have sphere shapes and a mean diameter of about 1 nm to about 5 nm.
[0011]In an exemplary embodiment, the hollow inorganic particles have sphere shapes and a mean diameter of about 20 nm to about 200 nm.
[0012]In an exemplary embodiment, the matrix part includes at least one of an acrylic-based polymer, a silicone-based polymer, a urethane-based polymer, or an imide-based polymer.
[0013]In an exemplary embodiment, the low-refractive index layer has a transmittance of about 95% or more in a wavelength of about 400 nm to about 700 nm, and a refractive index of about 1.1 to about 1.5 in a wavelength of about 632 nm.
[0014]In an exemplary embodiment, the first light is a blue light, the first conversion material is a first quantum dot that converts the blue light into a green light, and the second conversion material is a second quantum dot that converts the blue light into a red light.
[0015]In an exemplary embodiment, the electronic device further includes a display element disposed on the color conversion member.
[0016]In an exemplary embodiment, the display element includes a liquid crystal element.
[0017]In an exemplary embodiment, the light source member includes a guide panel and a light source disposed at one side of the guide panel. The low-refractive index layer is disposed between the guide panel and the color conversion member.
[0018]In an exemplary embodiment, the low-refractive index layer is directly disposed on the guide panel.
[0019]In an exemplary embodiment, the electronic device further includes a barrier layer disposed on at least one of top and bottom surfaces of the color conversion member.
[0020]In an exemplary embodiment, the color conversion member includes a plurality of color conversion parts that are spaced apart from each other on a plane. The color conversion parts include a first color conversion part including the first conversion material, a second color conversion part including the second conversion material, and a third color conversion part configured to transmit the first light.
[0021]In an exemplary embodiment, the color conversion member further includes a light blocking part disposed between the first to third color conversion parts spaced apart from each other.
[0022]In an exemplary embodiment, the electronic device further includes a reflection layer disposed on at least one of upper and lower portions of the color conversion parts. The reflection layer transmits the first light and reflects the second and third light.
[0023]In an exemplary embodiment, the low-refractive index layer is disposed between the reflection layer and the color conversion parts and covers the color conversion parts.
[0024]In an exemplary embodiment, the reflection layer is disposed between the low-refractive index layer and the color conversion parts and covers the color conversion parts.
[0025]In an exemplary embodiment, the color conversion member further includes a barrier layer disposed on at least one of upper and lower portions of the color conversion parts.
[0026]In an exemplary embodiment, the barrier layer is disposed between the low-refractive index layer and the color conversion parts and covers the color conversion parts.
[0027]In an exemplary embodiment, the color conversion member further includes an optical filter layer configured to transmit at least one of the second and third light.
[0028]In an exemplary embodiment, the optical filter layer includes a first optical filter layer disposed on the first color conversion part, and a second optical filter layer disposed on the second color conversion part.
[0029]In an exemplary embodiment, the first optical filter layer transmits a green light, and the second optical filter layer transmits a red light.
[0030]In an exemplary embodiment, the electronic device further includes a first base substrate disposed on the light source member, a second base substrate disposed on the light source member and facing the first base substrate, and a liquid crystal layer disposed on the light source member between the first and second base substrates. The color conversion member is disposed between the liquid crystal layer and the second base substrate.
[0031]In an exemplary embodiment, the low-refractive index layer is disposed between the liquid crystal layer and the color conversion member or between the color conversion member and the second base substrate.
[0032]In an exemplary embodiment, the electronic device further includes a first polarizing layer disposed between the light source member and the first base substrate or between the first base substrate and the liquid crystal layer, and a second polarizing layer disposed between the liquid crystal layer and the second base substrate.
[0033]In an exemplary embodiment, the light source member includes an organic electroluminescent element.
[0034]In an exemplary embodiment, the color conversion member further includes a dam part that partitions the color conversion parts from each other and is disposed between adjacent color conversion parts of the color conversion parts.
[0035]In an exemplary embodiment, the color conversion member further includes a color filter layer disposed on the color conversion parts. The color filter layer includes a plurality of filter parts configured to emit light having various colors, and a light blocking part configured to partition the filter parts from each other and disposed between adjacent filter parts of the filter parts.
[0036]According to an exemplary embodiment, an electronic device includes a light source member configured to provide a first light, a color conversion member disposed on the light source member and including a first conversion material that converts the first light into a second light and a second conversion material that converts the first light into a third light, and a low-refractive index layer disposed on the light source member and disposed on at least one of upper and lower portions of the color conversion member. The low-refractive index layer includes a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part and including a plurality of first voids, and a plurality of second voids defined by the matrix part. A mean diameter of the first voids is greater than a mean diameter of the second voids.
[0037]In an exemplary embodiment, the low-refractive index layer includes the plurality of first voids and the plurality of second voids. A first volume that is the sum of volumes of the first voids is greater than a second volume that is the sum of volumes of the second voids.
[0038]According to an exemplary embodiment, an electronic device includes a display element, a guide panel disposed below the display element, a light source member disposed adjacent to at least one surface of the guide panel, a color conversion member disposed between the guide panel and the display element, and a low-refractive index layer disposed between the guide panel and the color conversion member. The low-refractive index layer includes a matrix part, a plurality of hollow inorganic particles dispersed in the matrix part, and a plurality of void parts defined by the matrix part.
[0039]In an exemplary embodiment, the light source member includes a light emitting element configured to emit a blue light. The color conversion member includes a green quantum dot excited by the blue light to emit a green light, and a red quantum dot excited by at least one of the blue light and the green light to emit a red light.
[0040]In an exemplary embodiment, each of the hollow inorganic particles includes a core part filled with air and a shell part defining the core part, and a mean diameter of the core parts is greater than a mean diameter of the void parts.
具体实施方式：
[0063]Exemplary embodiments of the inventive concept will be described more fully hereinafter with reference to the accompanying drawings. Like reference numerals may refer to like elements throughout the accompanying drawings.
[0064]It will be understood that when a component, such as a film, a region, a layer, or an element, is referred to as being “on”, “connected to”, “coupled to”, or “adjacent to” another component, it can be directly on, connected, coupled, or adjacent to the other component, or intervening components may be present. It will also be understood that when a component is referred to as being “between” two components, it can be the only component between the two components, or one or more intervening components may also be present. It will also be understood that when a component is referred to as “covering” another component, it can be the only component covering the other component, or one or more intervening components may also be covering the other component.
[0065]Herein, the term “directly disposed” may mean that there is no layer, film, region, plate, etc. between a portion of the layer, the film, the region, the plate, etc. and the other portion. For example, “directly disposed” may mean being disposed without using an additional member such as an adhesion member between two layers or two members.
[0066]It will be understood that the terms “first,”“second,”“third,” etc. are used herein to distinguish one element from another, and the elements are not limited by these terms. Thus, a “first” element in an exemplary embodiment may be described as a “second” element in another exemplary embodiment. Further, the terms of a singular form may include plural forms unless referred to the contrary.
[0067]Spatially relative terms, such as “beneath”, “below”, “lower”, “under”, “above”, “upper”, etc., may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” or “under” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary terms “below” and “under” can encompass both an orientation of above and below. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.
[0068]The terms “about” or “approximately” as used herein are inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations as understood by one of the ordinary skill in the art. Further, it is to be understood that while parameters may be described herein as having “about” a certain value, according to exemplary embodiments, the parameter may be exactly the certain value or approximately the certain value within a measurement error as would be understood by a person having ordinary skill in the art.
[0069]It should be understood that descriptions of features or aspects within each exemplary embodiment should typically be considered as available for other similar features or aspects in other exemplary embodiments, unless the context clearly indicates otherwise.
[0070]Hereinafter, a low-refractive index layer and an electronic device including the low-refractive index layer according to exemplary embodiments of the inventive concept will be described with reference to the accompanying drawings.
[0071]FIG. 1 is an exploded perspective view of an electronic device according to an exemplary embodiment of the inventive concept. FIG. 2 is an exploded perspective view of a display member according to an exemplary embodiment of the inventive concept. For example, FIG. 2 is an exploded perspective view of a display member DP provided in an electronic device DS of FIG. 1 according to an exemplary embodiment of the inventive concept.
[0072]The electronic device DS according to an exemplary embodiment may include various elements that are activated according to an electrical signal such as a display element, a touch element, or a detection element. The electronic device DS according to an exemplary embodiment may include a window member WP, a display member DP, and an accommodation member HAU.
[0073]The electronic device DS according to an exemplary embodiment may be a display device including a display element and providing an image. For example, the electronic device DS according to an exemplary embodiment may be a liquid crystal display device or an organic electroluminescence display device.
[0074]In FIG. 1 and the following drawings, a first directional axis DR1, a second directional axis DR2, and a third directional axis DR3 are illustrated. The directional axes described herein are relative concepts, and for convenience of description, a direction of the third directional axis DR3 may be defined as a direction in which an image is provided to a user. The first directional axis DR1 and the second directional axis DR2 may be perpendicular to each other. The third directional axis DR3 may be a normal direction with respect to a plane defined by the first direction DR1 and the second direction DR2. In FIG. 1, the plane defined by the first directional axis DR1 and the second directional axis DR2 may be a display surface on which an image is provided.
[0075]In the electronic device DS according to an exemplary embodiment, the window member WP may be disposed on the display member DP. The window member WP may be made of a material including, for example, glass, sapphire, or plastic. The window member WP may include a light transmitting area TA that transmits an image provided from the display member DP, and a light blocking area BA which is disposed adjacent to the light transmitting area TA and through which the image is not transmitted. The light transmitting area TA may be disposed in a central portion of the electronic device DS on the plane defined by the first and second directional axes DR1 and DR2. The light blocking area BA may be disposed in the periphery of the light transmitting area TA and have a frame shape surrounding the light transmitting area TA. However, the inventive concept is not limited thereto. For example, in an exemplary embodiment, the window member WP may include only the light transmitting area TA, and the light blocking area BA may be omitted. Also, in an exemplary embodiment, the light blocking area BA may be disposed on only at least one side of the light transmitting area TA instead of surrounding the light transmitting area TA.
[0076]Unlike FIG. 1, the window member WP may be omitted in the electronic device DS according to an exemplary embodiment.
[0077]In the electronic device DS according to an exemplary embodiment, the display member DP may be disposed below the window member WP. The display member DP may include a liquid crystal display element or an organic electroluminescence display element.
[0078]A surface of the display member DP, on which an image is displayed, is defined as a display surface on a plane. The display surface includes a display area DA in which an image is displayed on the display surface and a non-display area NDA in which an image is not displayed. The display area DA may be defined at a center of the display member DP on the plane to overlap the light transmitting part TA of the window member WP.
[0079]The accommodation member HAU may be disposed below the display member DP to accommodate the display member DP. The accommodation member HAU may be disposed to cover the display member DP so that a top surface that is the display surface of the display member DP is exposed. In an exemplary embodiment, the accommodation member HAU may cover a side surface and a bottom surface of the display member DP and expose the entire top surface of the display member DP. In an exemplary embodiment, the accommodation member HAU may cover a portion of the top surface in addition to the side surface and the bottom surface of the display member DP.
[0080]Referring to FIG. 2, the electronic device DS according to an exemplary embodiment may include a low-refractive index layer LRL. The electronic device DS according to an exemplary embodiment may include a light source member LP, a color conversion member CCP disposed on the light source member LP, and the low-refractive index layer LRL disposed between the light source member LP and the color conversion member CCP according to an exemplary embodiment. The low-refractive index layer LRL provided in the electronic device DS according to an exemplary embodiment may be a layer that converts a path of light. For example, the low-refractive index layer LRL may function to extract light in relation to the adjacent layer or member.
[0081]The display member DP according to an exemplary embodiment, which is provided in the electronic device DS according to an exemplary embodiment, may include the light source member LP and a display element DD. The display member DP may include the color conversion member CCP disposed on the light source member LP, and the low-refractive index layer LRL disposed between the light source member LP and the color conversion member CCP.
[0082]In an exemplary embodiment, the low-refractive index layer LRL may be disposed on the light source member LP and may be disposed on at least one of upper and lower portions of the color conversion member CCP. In an exemplary embodiment, the low-refractive index layer LRL may be disposed directly on the guide panel GP. For example, the low-refractive index layer LRL may make direct contact with the guide panel GP.
[0083]The light source member LP may include a light source unit LU and a guide panel GP. The light source unit LU may provide first light. The light source unit LU may include a circuit board PB and a light emitting element LD disposed on the circuit board PB. The light source unit LU may also be referred to herein as a light source. In an exemplary embodiment, the light source unit LU is disposed at one side of the guide panel GP.
[0084]The circuit board PB may provide power to the mounted light emitting element LD. For example, the circuit board PB may provide a dimming signal and a driving voltage to the mounted light emitting element LD. The circuit board PB may include at least one insulation layer and at least one circuit layer. For example, the circuit board PB may be a metal core printed circuit board (MCPCB).
[0085]A plurality of light emitting elements LD may be disposed on the circuit board PB. The light emitting elements LD may emit light in response to a voltage supplied from the circuit board PB. Each of the light emitting elements may include a light emitting diode having a structure in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are sequentially laminated and emit light through recombination of electrons and holes when a driving voltage is applied.
[0086]In an exemplary embodiment, the plurality of light emitting elements LD may have light having the same wavelength range. In contrast, in an exemplary embodiment, the light source unit LU may include a plurality of light emitting elements LD that emit light having wavelength ranges different from each other. In an exemplary embodiment, the light emitting element LD may emit first light having a central wavelength in a wavelength range of about 440 nm to about 460 nm. In an exemplary embodiment, the light emitting element LD may emit blue light.
[0087]The light source member LP may include the guide panel GP. The light source unit LU may be disposed on at least one side of the guide panel GP. The first light emitted from the light source unit LU may be incident to at least one side of the guide panel GP. Then, the first light may be guided in the guide panel GP and provided to the display element DD. For example, the blue light emitted from the light source unit LU may be incident to the guide panel GP and transmitted to the color conversion member CCP. Thereafter, the light that is converted in wavelength may be provided from the color conversion member CCP to the display element DD.
[0088]In the exemplary embodiment of FIG. 2, although one side of the guide panel GP, which is adjacent to the light source unit LU, has a cross-section that is gradually inclined to one side surface of the guide panel GP, which is adjacent to the light source unit LU, the inventive concept is not limited thereto.
[0089]The guide panel GP may be made of a material having high light transmittance in a visible right region. For example, the guide panel GP may be glass. Alternatively, the guide panel GP may be made of a transparent polymer resin such as polymethyl methacrylate (PMMA). In an exemplary embodiment, the guide panel GP may have a refractive index of about 1.4 to about 1.55.
[0090]The light emitted from the light emitting element LD may be incident to the guide panel GP. An emission pattern part CP may be further disposed on a bottom surface of the guide panel GP. The emission pattern part CP may be disposed on the bottom surface of the guide panel GP and have a shape that convexly protrudes to the accommodation member HAU. For example, the emission pattern part CP may have a lens shape that is convex to the accommodation member HAU. However, the inventive concept is not limited thereto.
[0091]The emission pattern part CP may be made of a material having a refractive index different from that of the guide panel GP. The emission pattern part CP may transmit the light incident from the light source unit LU to one side surface of the guide panel GP to the other side surface of the guide panel GP, or change a direction of the incident light so that the light incident toward the bottom surface of the guide panel GP is transmitted toward the emission surface, which is a top surface of the guide panel GP. The emission pattern part CP may change a path of the light provided to the bottom surface of the guide panel GP to allow the light to be emitted to the display element DD.
[0092]In the display member DP according to an exemplary embodiment, the low-refractive index layer LRL may be disposed on the light source member LP. The low-refractive index layer LRL may be disposed on the guide panel GP.
[0093]FIG. 3 is a cross-sectional view of the low-refractive index layer according to an exemplary embodiment of the inventive concept. FIG. 4 is a flowchart illustrating a method of manufacturing the low-refractive index layer according to an exemplary embodiment of the inventive concept. FIGS. 5A to 5C are views illustrating processes in a method of manufacturing a low-refractive index layer according to an exemplary embodiment of the inventive concept.
[0094]FIG. 3 is a cross-sectional view of the low-refractive index layer LRL according to an exemplary embodiment of the inventive concept. Referring to FIG. 3, the low-refractive index layer LRL may include a matrix part MX, hollow inorganic particles HP, and void parts VD. As shown in FIG. 3, the low-refractive index layer LRL may include a plurality of hollow inorganic particles HP and a plurality of void parts VD.
[0095]The plurality of hollow inorganic particles HP may be spread throughout the matrix part MX, and the plurality of void parts VD may be defined by the matrix parts MX. For example, the void parts may correspond to portions that are not filled with the matrix part MX.
[0096]The matrix part MX may include a polymer material. The matrix part MX may include at least one of an acrylic-based polymer, a silicone-based polymer, a urethane-based polymer, or an imide-based polymer. For example, the matrix part MX may include one of polymeric materials selected from acrylic-based polymers, silicone-based polymers, urethane-based polymers, and imide-based polymers, or a combination of a plurality of polymer materials. Also, the matrix part MX may include at least one of a siloxane polymer, a silsesquioxane polymer, an acrylic-based polymer substituted with a fluorine atom, a silicone-based polymer substituted with a fluorine atom, a urethane-based polymer substituted with a fluorine atom, or an imide polymer substituted with the fluorine atom.
[0097]The matrix part MX may be made of, for example, an acrylic-based resin, a silicone-based resin, a urethane-based resin, or an imide-based resin. The matrix part MX may be formed by solidifying a polymer resin such as, for example, an acrylic-based resin, a silicone-based resin, a urethane-based resin, or an imide-based resin in a high temperature process or an ultraviolet treatment process.
[0098]In an exemplary embodiment, each of the hollow inorganic particles HP included in the low-refractive index layer LRL may have a core shell shape. In an exemplary embodiment, each of the hollow inorganic particles HP may have a sphere shape. Each of the hollow inorganic particles HP may include a core part CR and a shell part SL surrounding the core part CR. The core part CR may be defined by the shell part SL. For example, the shell part SL may surround the core part CR, and the core part CR may be defined by the inner wall of the shell part SL. In an exemplary embodiment, an entirety of an inner space of the shell part SL defined by the inner wall of the shell part SL may correspond to the core part CR. The shell part SL may be a layer made of an inorganic material. The shell part SL may include at least one of, for example, SiO2, MgF2, and Fe3O4. For example, in the low-refractive index layer LRL according to an exemplary embodiment, the hollow inorganic particle HP may be hollow silica.
[0099]The shell part SL in each hollow inorganic particle HP may include an inorganic layer defining the core part CR and made of at least one of, for example, SiO2, MgF2, and Fe3O4, and an organic layer surrounding an outer surface of the inorganic layer. The organic layer may serve to enhance the dispersibility of the hollow inorganic particles HP in the matrix part MX. For example, the organic layer may be disposed on an outer surface of the shell part SL to allow the hollow inorganic particles HP to be uniformly dispersed in the matrix part MX without agglomerating the hollow inorganic particles HP.
[0100]The core part CR of the hollow inorganic particles HP may be filled with air. However, the inventive concept is not limited thereto. For example, in an exemplary embodiment, the core part CR may be filled with a liquid or a gas having low refractive characteristics. In an exemplary embodiment, the core part CR may be a void defined by the shell part SL.
[0101]In an exemplary embodiment, the hollow inorganic particles HP may have the sphere shape. Also, a cross-section of each hollow inorganic particle HP may have a circular shape. The hollow inorganic particles HP may have a mean diameter of about 20 nm to about 200 nm. Referring to FIG. 3, a diameter DHP of the hollow inorganic particle HP may represent a diameter up to the outermost portion of the shell part SL. In an exemplary embodiment, the hollow inorganic particles HP included in the low-refractive index layer LRL may have a mean diameter of about 20 nm to about 200 nm, which results in an improved/optimized thickness and refractive index value of the low-refractive index layer LRL.
[0102]In the hollow inorganic particles HP, the shell part SL may have a thickness DSL of about 7 nm to about 10 nm. The shell part SL may have a thickness DSL of about 7 nm to about 10 nm to maintain strength of the hollow inorganic particles HP while increasing/maximizing a volume of the core part CR.
[0103]In the hollow inorganic particles HP, the core part CR may be filled with air, or a low-refractive index material may be included in the core part CR to control the refractive index of the low-refractive index layer LRL. For example, the hollow inorganic particle HP may have a refractive index of about 1.0 to about 1.3.
[0104]In an exemplary embodiment, the low-refractive index layer LRL may include a plurality of void parts VD. The void parts VD may be portions defined by the matrix part MX. The matrix part MX may be filled into the void parts VD. Thus, each of the void parts VD may be empty. For example, each void part VD may be an empty space defined to be surrounded by the matrix part MX. Each void part VD may be a portion that is filled with air. Each void part VD filled with the air may be a portion at which the refractive index of the low-refractive index layer LRL is reduced.
[0105]Each void part VD may be a space having a sphere shape. Referring to FIG. 3, each of the void parts VD may have a mean diameter DVD of about 1 nm to about 5 nm. In an exemplary embodiment, the low-refractive index layer LRL may include the void parts VD and the hollow inorganic particles HP, and thus, may have high durability while maintaining a low refractive index value.
[0106]In the low-refractive index layer LRL according to an exemplary embodiment, each void part VD defined by the matrix part MX may be an open pore, and each core part CR defined by the shell part SL may be a closed pore.
[0107]The void part VD corresponding to the open pore may be a portion that is not filled with the matrix part MX, and a boundary of the void part VD may be defined by the matrix part MX. Here, in an exemplary embodiment, a separate boundary material for dividing the void part VD and the matrix part MX is not provided. Also, in comparison, the core part CR corresponding to the closed pore may be an inner space of the hollow inorganic particle HP defined by the shell part SL.
[0108]In the low-refractive index layer LRL including the hollow inorganic particles HP and the void parts VD according to an exemplary embodiment, the core part CR that is the pore provided by the hollow inorganic particle HP may be defined as a first void, and the void part VD may be defined as a second void. For example, the low-refractive index layer LRL according to an exemplary embodiment may include the hollow inorganic particles HP having the first void and the void parts VD having the second void.
[0109]In an exemplary embodiment, each of the first void and the second void may have the sphere shape. In an exemplary embodiment, the first voids may have a mean diameter greater than that of the second voids. Referring to FIG. 3, the first void may have a diameter corresponding to a diameter DCR of the core part CR, and the second void may have a diameter corresponding to a diameter DVD of the void part VD. The diameter DCR of the hollow inorganic particle HP may represent a diameter up to the innermost portion of the shell part SL.
[0110]In the low-refractive index layer LRL according to an exemplary embodiment, the total volume of the plurality of first voids may be greater than that of the plurality of second voids. For example, a first volume that is the sum of the volumes of the first voids may be greater than that a second volume that is the sum of the volumes of the second voids. Thus, in an exemplary embodiment, the total volume of the first voids provided by all of the hollow inorganic particles HP may be greater than the total volume of the second voids provided by all of the void parts VD.
[0111]The low-refractive index layer LRL according to an exemplary embodiment may include all of the first voids corresponding to the closed pore defined by the shell part SL and the second voids corresponding to the void part VD defined by the matrix part MX.
[0112]In the low-refractive index layer LRL according to an exemplary embodiment, the void part VD may be made of a pore induction material (e.g., porogen). The low-refractive index layer LRL according to an exemplary embodiment may be formed by mixing a polymer resin, the pore induction material, and the hollow inorganic particles HP, and then by solidifying the polymer resin through a heat treatment process or ultra violet (UV) treatment process at a high temperature.
[0113]FIG. 4 is a flowchart illustrating a method of manufacturing the low-refractive index layer LRL according to an exemplary embodiment of the inventive concept. The method of manufacturing the low-refractive index layer LRL may include a process of mixing a polymer resin and a pore induction material to manufacture a preliminary coating solution (S100), a process of mixing a hollow inorganic particle into the preliminary coating solution to manufacture a coating solution (S200), and a process of performing heat treatment after applying the coating solution (S300).
[0114]The process of manufacturing the preliminary coating solution (S100) may be a process of mixing the polymer resin forming a matrix part MX with a pore induction material forming a void part VD. The preliminary coating solution may be a solution in which the polymer resin and the pore induction material are blended, or a solution in which the polymer resin and the pore induction material are polymerized in the form of a copolymer.
[0115]The polymer resin may include at least one of, for example, an acrylic-based polymer, a silicone-based polymer, a urethane-based polymer, or an imide-based polymer. For example, the polymer resin may include one of polymeric materials selected from acrylic-based polymers, silicone-based polymers, urethane-based polymers, and imide-based polymers, or a combination of a plurality of polymer materials. The polymer resin may include at least one of, for example, a siloxane polymer, a silsesquioxane polymer, an acrylic-based polymer substituted with a fluorine atom, a silicone-based polymer substituted with a fluorine atom, a urethane-based polymer substituted with a fluorine atom, or an imide polymer substituted with the fluorine atom. For example, the siloxane polymer may include organically modified silicate or a polymer to which a silane-based monomer is condensed.
[0116]The pore induction material included in the preliminary coating solution may be either linear type or dendrimer type.
[0117]For example, the linear type pore induction material may be a single molecule of hydrocarbon which may be represented by a chemical structure
[0118]
(x, y, and n are each independently an integer of 1 or more), branched poly(p-xylene), linear poly(p-phenylene), linear polybutadiene, branched polyethylene, polycarbonates, polyamideimide, polyphthalamide, polymethylstyrene, etc.
[0119]The dendrimer-type pore induction material may include a core portion and a branch portion bonded to the core portion so as to be connected in a regular branch structure and having a shape that is diffused to the outside. The core portion of the dendrimer-type pore induction material may be, for example, cyclosiloxane, cyclodextrin, bezene, etc. In the dendrimer type pore induction material, a hydrocarbon group which is represented by a chemical structure
[0120]
may be applied to the branch portion.
[0121]For example, when the polymer resin and the pore induction material are provided in the blended state in the preliminary coating solution, the polymer resin and the pore induction material may be in the mixed state without any chemical bonding.
[0122]For example, when the preliminary coating solution is provided in the polymerized state in the form of the copolymer in the preliminary coating solution, at least one of the above-described pore induction materials may be graft-polymerized to at least one of the above-described polymer resin materials. When the polymer resin and the pore induction material are provided in the polymerized state in the form of the copolymer, the pore induction material may be polymerized in the form of a bridge connecting the polymer resin materials to each other. When graft-polymerized, the plurality of pore induction materials which are bonded to the polymer resin by side chains may be the same or different from each other. When polymerized in the form of the bridge, the plurality of pore induction materials connecting the polymer resin materials to each other may be the same or different from each other.
[0123]In the following chemical structures, A-1 and A-2 represent cases in which a siloxane polymer is used as the polymer resin, and the pore induction material is graft-polymerized.
[0124]
[0125]The following chemical structures B-1 and B-2 represent cases in which a siloxane polymer is used as the polymer resin, and the pore induction material is polymerized in the form of the bridge between the siloxane polymers.
[0126]
[0127]The chemical structures A-1, A-2, B-1, and B-2 represent cases in which the polymer resin and the pore induction material are polymerized to be provided as the preliminary coating solution. In the chemical structures A-1, A-2, B-1, and B-2, PG, PG1, and PG2 represent the pore induction materials, respectively.
[0128]Referring to FIG. 4, in the method of manufacturing the low-refractive index layer, after the process of manufacturing the preliminary coating solution (S100) is performed, the process of mixing the hollow inorganic particle into the preliminary coating solution to manufacture the coating solution (S200) may be performed. For example, the polymer resin, the pore induction material, and the hollow inorganic particle may be included in the coating solution.
[0129]In an exemplary embodiment, unlike FIG. 4, the process of manufacturing the preliminary coating solution (S100) and the process of manufacturing the coating solution (S200) may be performed in the same process. For example, the polymer resin, the pore induction material, and the hollow inorganic particle may be mixed with each other in the same process and provided as the coating solution. For example, in an exemplary embodiment, the process of manufacturing the preliminary coating solution (S100) and the process of manufacturing the coating solution (S200) may be performed in the same process at substantially the same time.
[0130]For example, in the coating solution, the pore induction material may be included in an amount of about 1 wt % to about 20 wt %, and the hollow inorganic particle may be included in an amount of about 10 wt % to about 60 wt % on the basis of 100 wt % of the polymer resin.
[0131]When the content of pore induction material exceeds about 20 wt %, a ratio of the void parts in the low-reflective index manufactured from the coating solution according to an exemplary embodiment may be relatively high to deteriorate strength of the low-refractive index layer. Also, since the pore induction material is included in the coating solution at a content of about 1 wt % or more, the void part made of the pore induction material may be introduced into the low-refractive index layer to appropriately maintain the content of hollow inorganic particles so that the low-refractive index layer manufactured thereafter has a low refractive index. For example, since the pore induction material together with the hollow inorganic particles are used to maintain the low refractive index of the low-refractive index layer, the void part made of the pore induction material may be provided in the low-refractive index layer to partially reduce the content of hollow inorganic particles, thereby reducing manufacturing costs.
[0132]When the content of hollow inorganic particles in the coating solution on the basis of the polymer resin is less than about 10 wt %, the refractive index value of the low-refractive index layer manufactured from the coating solution may not be maintained to be low. Also, when the content of hollow inorganic particles on the basis of the polymer resin exceeds about 60 wt %, a haze value of the low-refractive index layer manufactured from the coating solution may increase.
[0133]Referring to FIG. 4, in the method of manufacturing the low-refractive index layer according to an exemplary embodiment, after the process of manufacturing the coating solution (S200) is performed, a process of applying the coating solution to thermally treat the applied coating solution (S300) may be performed. The applicati