Method for producing ultra-low refractive material and Anti-reflective coating solution using same

Abstract

The present invention provides: hollow magnesium fluoride particles characterized by being hollow particles having a magnesium fluoride coating film on the surface; a method for producing same; and an anti-reflective coating solution using same. The hollow magnesium fluoride particles according to the present invention have ultra-low refractive properties, and thus are highly suitable as an anti-reflective coating agent. An anti-reflective coating film formed using an anti-reflective coating agent according to the present invention is installed on an image display surface, such as a lens, a transparent plastic, a plastic film, or an image display device, and has a superb anti-reflective function.

Description

Method for manufacturing ultra-low refractive index materials and anti-reflection coating solution using the same

[0001] The present invention relates to ultra-low refractive index hollow particles.

[0002] The present invention relates to hollow magnesium fluoride (MgF2) particles and a method for producing the same, and more specifically, to low-refractive hollow magnesium fluoride particles that can be used as a coating agent for an anti-reflection film, a method for producing the same, and an anti-reflection coating solution using the same.

[0003] In general, the image display surface of image display devices such as lenses, transparent plastics, plastic films, cathode ray tubes, and liquid crystal displays is subjected to anti-reflection treatment to reduce reflection of external light such as sunlight or light and to increase light transmittance.

[0004] The present invention aims to solve the above-described problems and provide hollow magnesium fluoride particles exhibiting low refractive index characteristics and a method for producing the same.

[0005] And, the present invention aims to provide an anti-reflection coating solution using the hollow magnesium fluoride particles.

[0006] The present invention provides a hollow magnesium fluoride particle having a refractive index of 1.0 to 1.4 and a hollowness of 40% to 90%, characterized by having a magnesium fluoride coating film on the surface of the hollow particle.

[0007] The above hollow magnesium fluoride coating film is characterized in that the thickness is 1 to 30 nm, and the average diameter of the hollow is characterized in that the average diameter of the hollow is 20 to 300 nm.

[0008] Meanwhile, a silica coating film may be additionally included between the hollow body and the magnesium fluoride coating film.

[0009] The hollow magnesium fluoride particles of the present invention are:

[0010] A step of making a fine suspension core (template core) using a styrene monomer;

[0011] A step of adding ultrapure water to the above polystyrene suspension, stirring, and additionally adding ethanol to the reactor;

[0012] A step of mixing NH4F and ultrapure water and introducing them into the reactor;

[0013] A step of mixing MgCl2*6H2O and ultrapure water, putting them into a reactor, stirring, and maintaining them to form a MgF2 shell;

[0014] A step of filtering, washing and drying the aggregated particles in which the core shell is formed; and

[0015] It is characterized by being manufactured by a step of removing the core by calcining the above particles.

[0016] Meanwhile, a hollow nanoparticle having a refractive index of 1.0 to 1.4 and including a hollow core and multiple shells can be manufactured by a manufacturing method including: A) a step of forming a fine suspension core (template core) using a monomer; B) a step of forming a first shell using magnesium and an alkali salt; C) a step of forming a second shell using a silica precursor; and D) a step of forming a third shell using magnesium and an alkali salt; and E) a step of removing the fine suspension core (template core) by dissolving or calcining.

[0017] In the above manufacturing method, the fine suspension core (template core) is characterized by being a combination of one or two or more selected from the group consisting of polyester resin, styrene resin, acrylic resin, styrene-acrylic resin, polyolefin resin, polyamide resin, polyurethane resin, polycarbonate resin, and copolymers thereof.

[0018] In addition, the styrene resin is characterized by being a homopolymer or copolymer of styrene or a styrene substituent, such as polystyrene, polychlorostyrene, polyvinyltoluene, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyl toluene copolymer, styrene-vinylnaphthalene copolymer, etc., and in the case of a styrene-acrylic resin, it is characterized by being one or two or more polymers selected from the group consisting of styrene-methyl (meth)acrylate copolymer, styrene-ethyl (meth)acrylate copolymer, styrene-octyl (meth)acrylate copolymer, and styrene-phenyl (meth)acrylate copolymer.

[0019] Meanwhile, the magnesium raw material is characterized by being at least one selected from the group consisting of magnesium chloride, magnesium nitrate, magnesium sulfate, magnesium methoxide, magnesium ethoxide, and magnesium butoxide, and having a content of 0.1 mol to 1 mol.

[0020] The fluoride raw material is at least one selected from the group consisting of sodium fluoride, potassium fluoride, ammonium fluoride, and hydrogen fluoride (hydrofluoric acid), and is characterized in that its content is 0.1 mol to 1 mol.

[0021] Meanwhile, the present invention is characterized by providing an anti-reflection coating solution including hollow magnesium fluoride particles having a refractive index of 1.0 to 1.4 and a hollowness of 40% to 90%, characterized by having a magnesium fluoride coating film on the surface of the hollow particles.

[0022] The hollow magnesium fluoride particles according to the present invention have low refractive index characteristics by implementing the original refractive index characteristics of magnesium fluoride, and thus exhibit low refractive index characteristics, making them very suitable as an antireflection coating agent.

[0023] An anti-reflection film formed using an anti-reflection film coating agent according to the present invention is installed on an image display surface such as a lens, transparent plastic, plastic film, or image display device, and has an excellent anti-reflection function.

[0024] Figure 1 is a cross-sectional view of hollow magnesium fluoride particles and multi-shell hollow spheres,

[0025] Figure 2 is an SEM photograph of hollow magnesium fluoride particles.

[0026] The present invention relates to a method for manufacturing a ceramic composite hollow body capable of improving antireflection properties by using a low-refractive-index material having an extremely low refractive index using hollow particles of 2 to 300 nm, and to a low-refractive-index coating composition manufactured thereby.

[0027]

[0028] 1. Manufacturing of hollow magnesium fluoride particles

[0029] 1) PS core particle synthesis

[0030] To manufacture low-refractive-index hollow particles, a spherical polystyrene suspension is first polymerized using a polystyrene monomer raw material.

[0031]

[0032] 2) Formation of SiO2 shell

[0033] Ultrapure water is added to the prepared polystyrene suspension and stirred for 10 minutes. Ethanol is then added to the reactor. After 30 minutes, NH4OH is added to the reactor, followed by TEOS for 1 hour. The internal temperature of the reactor is maintained at 35°C during the addition, and the reaction is continued for a final 24 hours.

[0034] In the present invention, examples of silica precursors that can be used include tetnammethylorthosilicate (TMOS), tetraethylorthosilicate (TEOS), 3-mercaptopropyltrimethoxysilane (MPTMS), phenyltrimethoxysilane (PTMS), vinyltrimethoxysilane (VTMS), methyltrimethoxysilane (MTMS), 3-aminopropyltrimethoxysilane (APTMS), 3-glycidyloxypropyltrimethoxysilane (GPTMS), (3-trimethoxysilyl)propyl methacrylate (TMSPMA), 3-mercaptopropyltrimethoxysilane (MPTMS), 3-(trimethoxysilyl)propylisocyanate (TMSPI), and the like, and a mixing ratio of two or more types can be appropriately selected depending on the structure and particle size of the silica particles.

[0035]

[0036] 3) MgF2 shell formation

[0037] Ultrapure water is added to the manufactured polystyrene suspension, stirred for 10 minutes, and ethanol is additionally added to the reactor.

[0038] A) Mix NH4F and ultrapure water using a 1000ml beaker.

[0039] B) Prepare by mixing MgCl2*6H2O and ultrapure water using a 1000ml beaker.

[0040] After adding ethanol, the prepared solution A) is added to the reactor 30 minutes later, and solution B) is added to the reactor for 1 hour and stirred and maintained.

[0041]

[0042] 4) Multi-shell formation

[0043] SiO2, MgF2 in PS@SiO2, PS@MgF2 particles obtained in 2) and 3) above Double and triple shell particles are manufactured by additional reaction. After synthesis of latex particles, SiO2 First coating, then second coating with MgF2 and additionally SiO2 A triple shell can be formed by applying a third coating.

[0044]

[0045] 5) Filter and Clean

[0046] After core-shell particles are manufactured, the pH is lowered to neutral using a diluted nitric acid solution. This causes particle agglomeration, facilitating particle recovery. The agglomerated particles are recovered through a filter and further cleaned using ultrapure water.

[0047]

[0048] 6) Drying

[0049] The cake recovered through the filter can be dried at 60℃*24 hours to obtain particles with a core-shell formed.

[0050]

[0051] 7) Plasticity

[0052] When core-shell particles are formed and fired at 850°C for 4 hours to remove the core, hollow particles can be obtained. To minimize the rate of latex decomposition, the heat treatment was performed at a heating rate of 0.5 to 1°C / min.

[0053]

[0054] 8) Surface treatment

[0055] A silane compound having organic functional groups can be used as a coupling agent for surface treatment. It is preferable to select the silane compound that has excellent compatibility with the hollow particles, and for example, it may include at least one functional group selected from the group consisting of vinyl, epoxy, styryl, methacryloxy, acryloxy, amino, ureide, mercapto, and isocyanate, but is not limited thereto. It is preferable that the silane compound is an amino silane compound.

[0056] The silane coupling agent can be hydrolyzed before being applied to the ceramic. The hydrolysis can be performed using water or a solvent containing a hydroxyl group, preferably alcohol or ethanol for stability. The hydrolysis time is preferably at least 1 hour, and preferably 1 to 3 hours.

[0057] The above surface treatment can be performed using either a dry or wet method. Preferably, the wet method is used to enhance process efficiency. Surface treatment can be performed using both dry and wet methods, with 0.5-10 wt% of the powder (filler) added.

[0058]

[0059] 9) Dispersion

[0060] To disperse the surface-treated hollow particles in a solvent, preliminary dispersion was performed first, and dispersion was performed using a high-pressure homogenizer. The solvents used were mainly PGMEA and MIBK, and dispersion in silicone resins was also possible.

[0061]

[0062] Hereinafter, the present invention will be described in more detail through examples.

[0063] [Example 1] Synthesis of 170 nm particle size

[0064] (1) Add 1290 g of ultrapure water to a 2L double jacket reactor and stir at 250 rpm.

[0065] (2) Increase the temperature of the reactor to 80℃.

[0066] (3) When the temperature of the reactant reaches 80℃, add 0.29g of Initiator (KPS) + 150g of ultrapure water solution. After adding 80g of styrene, maintain the solution for 2 hours to produce particles with a particle size of 170nm.

[0067]

[0068] [Example 2] Synthesis of 130 nm particle size

[0069] (1) Add 1290 g of ultrapure water to a 2L double jacket reactor and stir at 250 rpm.

[0070] (2) Increase the temperature of the reactor to 80℃.

[0071] (3) When the temperature of the reactant reaches 80℃, add 0.14g of Initiator (KPS) + 150g of ultrapure water solution. After adding 7.0g of styrene, maintain for 2 hours to produce particles with a particle size of 130nm.

[0072]

[0073]

[0074] [Example 3] Hollow MgF2 manufacturing

[0075] (1) 316.8 g of the manufactured styrene 130 nm nanoparticles are weighed and placed in a 5 L reactor.

[0076] (2) (1) Add 2883.2 g of ultrapure water to the reactor and stir for 10 minutes.

[0077] (3) (1) Add 576 g of ethanol to the reactor and stir for 10 minutes.

[0078] (4) Mix 1.125 g of NH4F and 500 g of ultrapure water using a 1000 ml beaker.

[0079] (5) Mix 3.25 g of MgCl2*6H2O and 500 g of ultrapure water using a 1000 ml beaker.

[0080] (6) The prepared NH4F solution and MgCl2 solution are sequentially added to the reactor and the internal temperature of the reactor is maintained at 35℃ for 1 hour.

[0081]

[0082] [Example 4] Hollow SiO2 production

[0083] (1) 316.8 g of the manufactured styrene 130 nm nanoparticles are weighed and placed in a 5 L reactor.

[0084] (2) (1) Add 2883.2 g of ultrapure water to the reactor and stir for 10 minutes.

[0085] (3) (1) Add 576 g of ethanol to the reactor and stir for 10 minutes.

[0086] (4) TEOS is added to the reactor, and NH4OH is added continuously. Simultaneously with the addition, the internal temperature of the reactor is maintained at 35℃ for 1 hour.

[0087]

[0088] [Example 5] Manufacturing of multi-shell hollow spheres

[0089] (1) 316.8 g of manufactured styrene nanoparticles (130 nm) are placed in a 5 L reactor.

[0090] (2) Add 2883.2 g of ultrapure water to the reactor and stir for 10 minutes.

[0091] (3) Add 576 g of ethanol to the reactor and stir for 10 minutes.

[0092] (4) TEOS is added to the reactor, and NH4OH is continuously added. Simultaneously with the addition, the internal temperature of the reactor is maintained at 35°C for 1 hour.

[0093] A) Mix 1.125 g of NH4F and 500 g of ultrapure water using a 1000 ml beaker.

[0094] B) Mix 3.25g of MgCl2*6H2O and 500g of ultrapure water using a 1000ml beaker.

[0095] (5) When 1 hour has passed since the reaction of (4), the prepared NH4F solution and MgCl2 solution are sequentially added to the reactor and maintained at 35°C for 1 hour.

[0096] (6) When the retention time is over, filter.

[0097] (7) Dry the recovered cake at 60℃ for 24 hours.

[0098] (8) Fire at 850℃ for 4 hours.

Claims

1. Hollow magnesium fluoride particles having a refractive index of 1.0 to 1.4 and a hollowness of 40% to 90%, characterized by having a magnesium fluoride coating film on the surface of the hollow particles.

2. Hollow magnesium fluoride particles according to claim 1, characterized in that the thickness of the magnesium fluoride coating film is 1 to 30 nm.

3. A hollow magnesium fluoride particle characterized in that, in the first paragraph, a silica coating film is additionally included between the hollow particle and the magnesium fluoride coating film.

4. Hollow magnesium fluoride particles according to claim 1, characterized in that the average diameter of the hollow particles is 20 to 300 nm.

5. Step of making a fine suspension core (template core) using a styrene monomer; A step of adding ultrapure water to the above polystyrene suspension, stirring, and additionally adding ethanol to the reactor; A step of mixing NH4F and ultrapure water and introducing them into the reactor; A step of mixing MgCl2*6H2O and ultrapure water, putting them into a reactor, stirring, and maintaining them to form a MgF2 shell; A step of filtering, washing and drying the aggregated particles in which the core shell is formed; and A hollow magnesium fluoride particle comprising a step of calcining the particle to remove the core. 6.A) Step of making a micro suspension core (template core) using a monomer; B) Step of forming a first shell using magnesium and alkali salt; C) forming a second shell using a silica precursor; and D) forming a third shell using magnesium and alkali salts; and E) A method for producing hollow nanoparticles having a refractive index of 1.0 to 1.4, including a hollow core and multiple shells, comprising a step of removing the fine suspension core (template core) by dissolving or calcining.

7. In the 6th paragraph, the micro suspension core (template core) is characterized in that it is a combination of one or two or more selected from the group consisting of polyester resin, styrene resin, acrylic resin, styrene-acrylic resin, polyolefin resin, polyamide resin, polyurethane resin, polycarbonate resin and copolymers thereof.

8. In the 7th paragraph, the styrene resin is a homopolymer or copolymer of styrene or a styrene substitutent, such as polystyrene, polychlorostyrene, polyvinyltoluene, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyl toluene copolymer, styrene-vinylnaphthalene copolymer, etc., and in the case of a styrene-acrylic resin, a manufacturing method in which one or two or more polymers are selected from the group consisting of styrene-methyl (meth)acrylate copolymer, styrene-ethyl (meth)acrylate copolymer, styrene-octyl (meth)acrylate copolymer, and styrene-phenyl (meth)acrylate copolymer.

9. A method for producing hollow magnesium fluoride particles, characterized in that in paragraph 6, the magnesium raw material is at least one selected from the group consisting of magnesium chloride, magnesium nitrate, magnesium sulfate, magnesium methoxide, magnesium ethoxide, and magnesium butoxide, and the content thereof is 0.1 mol to 1 mol.

10. A method for producing hollow magnesium fluoride particles, characterized in that in paragraph 6, the fluoride raw material is at least one selected from the group consisting of sodium fluoride, potassium fluoride, ammonium fluoride, and hydrogen fluoride (hydrofluoric acid), and the content thereof is 0.1 mol to 1 mol.

11. An anti-reflection coating solution comprising hollow magnesium fluoride particles having a refractive index of 1.0 to 1.4 and a hollowness of 40% to 90%, characterized by having a magnesium fluoride coating film on the surface of the hollow particles.

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