Fluorescent composition having low light diffusion and color deviation, and LED and device using same

Abstract

The present invention provides: a fluorescent light diffusion / low reflection coating composition in which fluorescent hollow particles and a silicone resin are mixed; and a substrate and a device using same. A fluorescent hollow particle + silicone resin structure composition according to the present invention can provide a light diffusion effect, prevent deterioration of optical properties, and impart optical properties (Blue, Red, and Green are all possible, and in particular, a Blue coating prevents deterioration of Blue properties).

Description

Fluorescent composition with low light diffusion and color deviation, and LED and device using the same

[0001] The present invention relates to a fluorescent light-diffusing / low-reflection composition, an LED and a device using the same, and a method for manufacturing the same.

[0002] LEDs have been actively developed since 1992 when Nakamura et al. of Nichia, Japan, successfully fused high-quality single-crystal GaN nitride semiconductors by applying a low-temperature GaN compound buffer layer. LEDs are semiconductor devices that convert electrical signals into light with a desired wavelength range and display them by utilizing the characteristics of compound semiconductors, which have a structure in which an n-type semiconductor crystal, in which the majority of carriers are electrons, and a p-type semiconductor crystal, in which the majority of carriers are holes, are joined together. Nitride semiconductors (GaN) have a band gap of 3.4 eV and are one of the most chemically stable semiconductors, and have the advantage of being environmentally friendly because they do not contain environmentally hazardous substances such as arsenic (As) and mercury (Hg).

[0003] Typically, lighting devices have a light source that emits light internally, and a diffusing means, such as a lens, is used to diffuse or focus the light emitted from the light source. For this purpose, the lens is typically made of glass or hardened plastic. Consequently, its self-weight increases, making the lighting device heavier. This, in turn, increases the supporting load of auxiliary facilities such as supports for installation, leading to higher installation costs. Furthermore, the nature of lighting devices requires a greater number of components, which in turn increases production costs and limits installation locations due to the increased load.

[0004] In the case of LED, a composition such as silicone resin + fluorescent material (green and red fluorescent material) + anti-sedimentation agent + diffusion agent is dotted on a blue chip and then heat-cured or UV-cured to produce a lens. However, the effect of the anti-sedimentation agent is minimal, so there is a problem of color deviation due to sedimentation of coarse fluorescent material, and the diffusion agent uses spherical particles of 0.3 to 2㎛ in size, so the light efficiency decreases as much as the diffusion effect occurs.

[0005] The purpose of the present invention is to produce a lens with low optical characteristics, light diffusion, and color deviation by mixing only fluorescent hollow particles and silicone resin.

[0006] The present invention is characterized by manufacturing a lens with excellent optical properties, light diffusion, and minimal color deviation by mixing only fluorescent hollow particles and silicone resin. Hollow silicas produced by the sol-gel method are used, and sol-gel silica is silica obtained through a solvent removal and drying process from a silica sol suspension produced by hydrolysis and condensation reaction of alkoxy silane in an organic solvent containing water using a catalyst, and is characterized by having a single spherical particle shape.

[0007] In the present invention, the hollow particle range is 0.03 to 3㎛, and the hollowness is characterized by 20 to 80%.

[0008] In addition, the material of the hollow particles is characterized by being hollow particles such as silica, MgF2, and polymer (PMMA, PS, PC).

[0009] The composition of the present invention comprises a step of manufacturing hollow particles manufactured by a sol-gel method; a step of structuring the manufactured hollow particles, a fluorescent substance (red, green), and a silicone resin.

[0010] The composition of the present invention comprises a fluorescent substance (red, green) + hollow particles + silicone resin, wherein the hollow particles are added in an amount of 0.01 to 3% of the total composition. In addition, the curing method is characterized by being thermal curing or UV curing.

[0011] The composition of the present invention is characterized by providing a light diffusion effect, preventing degradation of optical properties, and imparting optical properties (blue, red, and green are all possible, but blue coating in particular prevents degradation of blue properties). In addition, the composition of the present invention can replace OLED, LED, QD Film, and LCD light diffusion film.

[0012] We used silica manufactured in a sol-gel type that allows for size control of various silica particles while having a narrow particle size distribution, and it has the advantage of easy particle size control from 10 nm to 200 nm. In addition, the difference in charging depending on the environment was minimized by performing hydrophobic silane treatment such as PDMS, HMDS, DMDES, and OTES.

[0013] To produce multi-color light emission such as red, green, blue, yellow, and orange, carbon dots were doped with nitrogen or acid-treated, and inorganic nano metal oxide particles with sizes ranging from several nm to several tens of nm were brought into proximity to increase electron mobility, thereby producing various multi-color light-emitting phosphors under UV light.

[0014] The above complex is characterized in that carbon dots having a diameter of 2 to 10 nm are bonded to the surface of carbon quantum dots by providing hydroxyl and carbxyl groups so that they can form clusters with inorganic nanoparticles having a diameter of 2 to 50 nm, and by controlling electrostatic attraction or repulsion and hydrogen bonding with the inorganic nanoparticles.

[0015] In addition, the complex is characterized by exhibiting red, green, blue, yellow, and orange fluorescence characteristics depending on the content of carbon dots, the content of nitrogen, and the type and size of inorganic nanoparticles when irradiated with 365 nm UV.

[0016] Meanwhile, in the above complex, the carbon dot comprises polysaccharides such as biomass-based cellulose, hemicellulose, and lignin, monosaccharides or disaccharides such as glucose, sucrose, and xylose, and acids such as citric acid, and is characterized in that it is manufactured through a hydrothermal reaction in water using these raw materials as they are or after acid treatment. Biomass-based materials may be selected from the group consisting of pulp materials such as UNP (unbleached kraft pulp), BKP (bleached kraft pulp), and TMP (thermo mechanical pulp), recycled paper materials such as ONP (old news paper), OCC (old corrugated container), OMP (old magazine printing matters), MOP (mixed office paper), and milk cartons, and food-based recycled materials such as starch or citric acid, such as rice bran, coffee grounds, and fruit juice.

[0017] In order to increase the fluorescence intensity and express multi-color, the inorganic nanoparticles used for hybrid are spherical particles of 2 to 50 nm, such as Europium, SiO2, TiO2, ZnO, Fe2O3, CuO, MgO, Mg(OH)2, Al2O3, Nd2O3, Ce2O3, Er2O3, Dy2O. It is characterized by comprising one or more components selected from the group such as .

[0018] Hollow silica-organic ligand structures, or hollow silica-carbon dot structures, possess tunable optical properties with excitation emission and are highly attractive due to their high photochemical and colloidal stability, excellent biocompatibility, easy-to-use fabrication process, and low raw material cost. As mentioned above, they are composed solely of C, N, and O, making them completely metal-free and eco-friendly materials for safe, advanced applications. In addition to their use in surface treatment of substrates, these materials have been extensively studied in a wide range of applications, including optoelectronics, light-emitting diodes, chemical and biosensing, bioimaging, drug delivery, photo- and electrocatalysis, latent fingerprint detection, and anti-counterfeiting.

[0019] The composition of the present invention, which mixes only the fluorescent hollow particles of the present invention + silicone resin, can provide a light diffusion effect, prevent deterioration of optical properties, and impart optical properties (blue, red, and green are all possible, but blue coating in particular prevents deterioration of blue properties).

[0020] The present invention relates to a light diffusion / low-reflection composition and a substrate or optical element using the same, and more particularly, to a low-reflection optical film and an optical element using the same, which can maximize the display image effect by obtaining high anti-glareness without lowering the high-definition display image quality and reducing the reflectance of the surface by applying a low-reflection coating treatment to an anti-glare film on which a light diffusion coating layer is applied using hollow silica particles, and at the same time. In addition, the composition of the present invention can replace OLED, LED, QD Film, and LCD light diffusion Film.

[0021] Figure 1 is a schematic diagram of a lens to which the composition of the present invention is applied.

[0022] Figure 2 is a schematic diagram of a typical diffusion film.

[0023] To facilitate understanding of the present invention, preferred examples are presented below. However, the following examples are provided solely to facilitate understanding of the invention and are not intended to limit the scope of the present invention.

[0024]

[0025] Example

[0026] 1. Preparation of hollow silica particles

[0027] Disperse 40 g of wet cake silica in water. Dissolve 15 g of CTAB in water to make a solution. Add the silica dispersed in water to the CTAB solution and stir for 30 minutes to coat the silica with CTAB. Meanwhile, dissolve 170 g of Na2CO3 in water to make a solution. Add the Na2CO3 solution to the CTAB-coated silica. Stir for 6 hours while maintaining the reaction temperature at 50°C. Once stirring is complete, filter the supernatant and separate the slurry. Disperse the separated slurry in water. Add the Na2CO3 solution to the dispersed slurry. Stir for 2 hours while maintaining the reaction temperature at 50°C. Once stirring is complete, filter the supernatant, wash with UP, and dry at 60°C. Once drying is complete, calcinate at 800°C for 4 hours.

[0028]

[0029] 2. Preparation of nano-hollow silica-organicligand structures

[0030] Organic ligand was dissolved in water at 1% and dispersed at 90°C for 1 hour with high-speed stirring (1000 rpm). The dispersed organic ligand was added to 10 nm silica sol at 1% of the silica solid content and stirred for 30 minutes to proceed with the reaction. The organic ligand reacted on the silica surface, and it was confirmed that the dispersion was maintained in a stable state due to electrostatic repulsion even after long-term standing due to the carboxyl group of the organic ligand.

[0031] The fluorescence characteristics of this nano hollow silica-organic ligand structure sol with good dispersibility were confirmed at UV 365 nm, and it exhibited blue luminescence characteristics as shown in Fig. 2.

[0032] The above structure was treated with one or more hydrophobic silanes, PDMS, HMDS, OTES, and DMDES, and then dried at 90°C for 24 hours. The dried structure was milled again to produce a final powder.

[0033]

[0034] 3. Preparation of carbon dot-nano hollow silica particles

[0035] 1) Manufacturing method through continuous process

[0036] During the above sol-gel silica manufacturing process, carbon dots were added to ensure uniform distribution of carbon dots within the silica. 1 mol of distilled water and 0.2 mol of NH3 were stirred at 300 rpm for 10 minutes. The mixture was heated to 48°C and 0.2 mol of TEOS was added dropwise. Carbon dots were added immediately after adding TEOS and aged for 2.5 hours before collecting samples.

[0037]

[0038] 2) Manufacturing method through two-step reaction

[0039] The two-step reaction method first produces nanoparticle silica using a sol-gel process and then proposes a method of bonding carbon dots onto the silica surface. First, 100 nm silica was produced using the above-mentioned nano-silica production method, and the silica solution was treated with N-2(aminoethyl)-3-aminoprophyl trimethoxy silane. The surface charge of the silica solution was confirmed to change positively from -30 mV to +20 mV when measuring the zeta potential by amino silane treatment. To the positively changed silica surface, 3% of negatively charged CD was added based on silica solid. After adding CD, the zeta potential was measured to be -10 to +5 mV. The final solution was centrifuged to remove the supernatant, and the remaining particles were dried at 100°C for 2 hours.

[0040]

[0041] 4. Preparation of fluorescent polymerization substrate

[0042] In addition to the method of manufacturing by coagulating the above silica-organic ligand structure or carbon dot inside the substrate, the method of manufacturing by treating the outer surface of the substrate is as follows.

[0043] The composition of the present invention comprises a step of manufacturing hollow particles manufactured by a sol-gel method; a step of structuring the manufactured hollow particles, a fluorescent substance (red, green), and a silicone resin.

[0044] The composition of the present invention comprises a fluorescent substance (red, green) + hollow particles + silicone resin, wherein the hollow particles are added in an amount of 0.01 to 3% of the total composition. The coating layer is cured by thermal curing or UV curing.

[0045] The composition of the present invention is characterized by providing a light diffusion effect, preventing degradation of optical properties, and imparting optical properties (blue, red, and green are all possible, but blue coating in particular prevents degradation of blue properties). In addition, the composition of the present invention can replace OLED, LED, QD Film, and LCD light diffusion film.

[0046]

[0047] Fluorescent Silica 100nm Fluorescent Silica 50nm Fluorescent Silica 10nm Fluorescent Characteristics Fluorescent Color Example 11○Blue Example 22○+Blue Example 31○Blue Example 42○+Blue Example 51○Blue Example 62○+Blue Comparative Example 7000XBlue

[0048] Method for coating the surface of a substrate with fluorescent silica

Claims

1. A fluorescent light-diffusion / low-reflection coating composition mixing fluorescent hollow particles and silicone resin.

2. A composition characterized in that, in the first paragraph, the hollow particles are included in the composition at 0.01 to 3%.

3. A composition according to claim 1, characterized in that the hollow particles are at least one selected from silica, MgF2, PMMA, PS, and PC.

4. A composition characterized in that the hollow particles in the first paragraph have a particle diameter of 0.03 to 3 ㎛ and a porosity of 20 to 80%.

5. An LED and device to which the composition of any one of claims 1 to 4 is applied.

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