TWI634074B - Hollow-type aluminosilicate nanoparticle and preparation method thereof - Google Patents

Abstract

The invention relates to a hollow type aluminum silicate particle and a preparation method thereof, and the preparation method of the hollow type aluminum silicate particle comprises the following steps, which are composed of a microcapsule or a reverse micell of an organic polymer. a template core for reacting a decane compound and an aluminum precursor to form a core-shell particle forming an aluminum niobate shell; allowing the core-shell particle to react with an aqueous alkaline solution or an acidic aqueous solution to form micropores on the shell, and At the same time, the core is removed to form hollow type aluminum niobate particles; and the hydrothermal reaction is carried out in order to increase the density of the hollow type aluminum niobate particles.

The hollow type aluminum niobate particle of the present invention and the preparation method thereof form a negative charge during the formation of the composite oxide in the reaction of the aluminum precursor and the ceria precursor to form a shell, so that it is not necessary to further carry out the nuclear surface The treatment also forms a uniform shell, and under the high-density reaction, the shell is not damaged to form uniform hollow particles.

Description

Hollow type aluminum silicate particle and preparation method thereof

The present invention relates to a hollow type aluminum silicate particle and a preparation method thereof. In more detail, the hollow type aluminum silicate particle and the preparation method thereof can remove the organic polymer inside the shell without a high-temperature sintering process, thereby realizing Low cohesion, excellent dispersibility, and excellent density due to hydrothermal reaction.

Microparticles having a hollow form are generally used as materials for displays and lenses that require low reflection characteristics at a low refractive index, and can also be used as materials for heat insulating materials and drugs requiring hollow morphological characteristics and low refractive properties. Transmitter, low dielectric, etc.

In the prior art, in the preparation of hollow particles having a particle diameter of 0.03 to 380 Å, in particular, the prior art is used in the preparation of hollow cerium oxide particles in an aqueous solution of an acid ‧ alkali metal in the core (other than cerium oxide) After the active ceria is reacted to form a ceria shell, the core is removed without destroying the ceria shell.

Specifically, the above preparation method forms a template nucleus formed by an acid or a base such as zinc, iron oxide or aluminum ruthenate oxide. The template core particles form a ceria shell by using water glass or a decane polycondensation substance, and then dissolve the internal (nuclear) substance by a strong acid or a strong alkali. However, the above method is difficult to adjust the size of the core and the size of the shell, and requires a process such as ion exchange resin or ultrafiltration, which is not only complicated but also requires a lot of cost.

To this end, the following hollow type citrate particle preparation method has been proposed, that is, a core is formed using a polymer such as an epoxy polymer, and a nucleate shell is grown on the nucleus to remove a core (polymer) ). The particles prepared by the above method are more difficult to remove the polymer inside the shell by water or other solvent because of the dense structure of the ceria shell.

Therefore, a method for preparing hollow type cerium oxide by burning and removing the template polymer at a high temperature has been proposed. However, during the high-temperature combustion process, the hollow cerium oxide particles are agglomerated with each other, and it is difficult to re-disperse the prepared particles on the solution, and haze or transmittance is formed on the coating film when applied for optical use. Lower.

Further, a process for preparing hollow particles by using a template polymer as a core is added such as PVP (Poly Vinyl Pirrolidone), PAH (Polycyclic aromatic hydrocarbon), AIBN (PS core), and metal in order to uniformly form a substance constituting the shell on the surface of the core. A polymer electrolyte such as a salt exhibits a strong positive ion, but after the preparation of the hollow type cerium oxide, the positive ions remain and the surface treatment cannot be further performed, so that the solvent is not replaced and the dispersion is insufficient. .

Further, Korean Patent No. 1,461,203, in order to prepare a shell having micropores, adds a metal oxide to the niobate particles and dissolves the metal oxide in an alkali or an acid solution to pass through the microporous solution. The hollow particles are prepared by nucleating particles, and the micropores formed in the shell prevent the particles constituting the shell from being uniformly formed and the shell is damaged during the subsequent densification of the shell, and it is difficult to form high-density uniform hollow particles.

Therefore, there is an urgent need to develop a hollow type aluminum niobate particle which has micropores and which can easily remove the core and make the particles constituting the shell uniform, and a preparation method thereof.

Prior technical literature Patent literature

1. Japanese public patent 2011-042527

2. Japanese Open Patent 2010-131593

3. Korean Patent No. 1461203

A technical object to be achieved by the technical idea of the present invention is to provide a hollow type aluminum niobate particle which does not form an aluminum gallate shell on a core composed of an organic polymer. The organic polymer inside the shell is removed by a high-temperature sintering process to obtain low cohesion, excellent dispersibility, and excellent density due to hydrothermal reaction.

In particular, it is an object of the present invention to provide a high-density hollow type particle without damaging the shell particles by adjusting the content of aluminum forming micropores when the niobate shell particles are formed.

Moreover, another object of the present invention is to provide a method for preparing hollow type aluminum niobate particles, which forms a negative charge during the formation of a composite oxide by reacting an aluminum precursor and a ceria precursor to form a shell. Therefore, it is not necessary to further carry out nuclear surface treatment. A uniform shell is formed, and uniform hollow particles are not formed under the high-density reaction without causing damage to the shell.

However, these problems are provided by way of example only, and the technical idea of the present invention should not be limited accordingly.

The present invention can achieve the above technical problems, and a method for preparing hollow type aluminosilicate particles according to the technical idea of the present invention includes the following steps in a microcapsule or a reverse micell from an organic polymer. Forming a template core on the decane compound and the aluminum precursor to form a core-shell particle forming an aluminum niobate shell; allowing the core-shell particle to react with an aqueous alkaline solution or an acidic aqueous solution to form a shell At the same time, the micropores are formed, and the core is removed to form hollow aluminum niobate particles; and the hydrothermal reaction is carried out in order to increase the density of the hollow aluminum niobate particles.

In a part of the embodiment of the invention, the aluminum gallate shell contains X moles of Si element and Y mole of Al element, and the above X/Y molar ratio is 7 to 15.

In some embodiments of the invention, the hydrothermal reaction step described above can be carried out at a temperature of from 160 to 230 °C.

In some embodiments of the present invention, the hollow type aluminum silicate nanoparticles may have an average particle size of 10 to 300 nm, and the shell thickness is 5 to 15 nm.

In some embodiments of the present invention, the organic polymer may be a copolymer or a block copolymer, and the copolymer or block copolymer comprises a selected from the group consisting of polyoxyethylene, polyoxyethylene glycol, and polyoxygen. Polyoxypropylene alkyl ether, polyoxypropylene Monoalkyl ether, polyoxypropylene alkyl, polyoxyethylene tallowamine, polyoxyethylene oleyl amine, polyoxyethylene stearyl amine, Polyoxyethylene lauryl amine, polyoxyethylene sorbitan ester, polyoxyethylene octyl ether, polyoxyethylene glyceryl ether, polyacrylic acid, polysulfonic acid, poly A polymer of a group consisting of polyacryl amine and triethylene amine.

In a part of the embodiment of the invention, the above decane compound is represented by the following Chemical Formula 1.

(In the above formula, R1, R2, R3 and R4 are each independently alkyl, alkoxy, phenyl, vinyl, halo group, epoxy group, glycidoxy group , amino or sulfur (mercapto group)

In some embodiments of the invention, the aluminum precursor may be an organic salt of aluminum or an aluminum alkoxide.

In some embodiments of the present invention, the alkaline aqueous solution may be sodium hydroxide, ammonium hydroxide, potassium hydroxide, hydroxy phosphate or a mixed solution thereof, and the acidic aqueous solution is hydrochloric acid, nitric acid, sulfuric acid, acetic acid or the like. mixture.

The present invention can achieve the above technical problems, and the composition for forming a film according to the technical idea of the present invention comprises the above hollow type aluminum niobate particles.

In some embodiments of the present invention, the hollow type aluminum silicate nanoparticles may have an average particle size of 10 to 300 nm, and the shell thickness is 5 to 15 nm.

An antireflection film according to the technical idea of the present invention which achieves the above technical problem includes a transparent film coated by the above-described composition for forming a film.

In some embodiments of the present invention, the antireflection film has a transmittance of at least 3%, a refractive index of 1.31 or less, a reflectance of 1.5 or less, and a Haze of 1 or less.

According to the technical idea of the present invention, the hollow type aluminum niobate particles form an aluminum citrate shell on a core composed of an organic polymer, and the organic polymer inside the shell is removed without undergoing a high-temperature sintering process, and the degree of aggregation is low and the dispersibility is excellent. High density by hydrothermal reaction.

Moreover, the method for preparing hollow type aluminum niobate particles according to the present invention forms a charge during the formation of the shell by reacting the aluminum precursor and the ceria precursor to form a composite oxide without further nuclear surface treatment. It is also possible to form a uniform shell, and to form a uniform hollow type particle without causing damage to the shell under high-density reaction.

The above effects of the present invention are provided by way of example only, and the scope of the present invention should not be limited by these effects.

1 is a conceptual diagram showing a method of preparing hollow type aluminum niobate particles according to the present invention.

2 is a TEM photograph of hollow type aluminum niobate particles prepared according to Examples and Comparative Examples of the present invention.

Fig. 3 is a TEM photograph of hollow type cerium oxide particles prepared and subjected to a high density reaction according to an example of the present invention and a comparative example.

Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The embodiments of the present invention are helpful for those skilled in the art to have a more complete understanding of the technical idea of the present invention. The following embodiments may be in various other forms and may not limit the scope of the technical idea of the present invention. In the examples below. Rather, these embodiments are capable of making the disclosure of the present invention more substantial and complete, and to facilitate the complete disclosure of the technical idea of the present invention to those skilled in the art. As indicated in the specification of the present invention, the term "and/or" includes any one of the listed items and all combinations of one or more items. The same symbol always represents the same element. Further, various elements in the drawings are schematically illustrated in the field. Therefore, the technical idea of the present invention is not limited to the relative size or spacing drawn in the drawings.

1 is a conceptual diagram showing a method of preparing hollow type aluminum niobate particles according to the present invention. The method for producing hollow type aluminum niobate particles according to the present invention comprises the steps of: preparing core-shell particles, forming a hollow type aluminum niobate particle, and performing a hydrothermal reaction.

The step of preparing the core-shell particles is carried out by reacting a decane compound and an aluminum precursor on a template core composed of a microcapsule or a reverse micelle of an organic polymer to form a ruthenium. Core-shell particles of an aluminum acid shell.

The template core may be formed in the form of a microcell or a reverse micell in a solvent. The above micelle or reverse micell are prepared from an organic polymer. The organic polymer exhibits a hydrophobic and hydrophilic bidirectional functional group property, and the bidirectional functional group has a property of binding between functional groups exhibiting the same characteristics. Therefore, when a hydrophobic functional group is formed inside, a functional group opposite thereto is formed externally, that is, a hydrophilic functional group is formed externally, and when a hydrophilic functional group is formed inside, a hydrophobic functional group is formed externally to form a microshell. The functional group characteristics vary depending on factors such as the polarity of the solvent to be added at the time of preparing the micelle and the molecular weight of the functional group.

That is, the above-mentioned organic polymer forms uniform micelles or anti-micropore-like particles in a specific solvent, is easily dispersed in a solvent, and has a binding force with a decane compound forming a shell.

As the organic polymer, a polymer copolymer or a block copolymer can be used. The copolymer or block copolymer of the above polymer usually functions as a surfactant. In this case, the polymer may be specifically used, polyoxyethylene, polyoxyethylene glycol, polyoxypropylene alkyl ether, polyoxypropylene monoalkyl ether, polyoxypropylene alkyl, polyoxyethylene tallow amine, polyoxygen Vinyl oleylamine, polyoxyethylene octadecylamine, polyoxyethylene dodecylamine, polyoxyethylene sorbitol ether, polyoxyethylene octyl ether, polyoxyethylene glyceryl ether, polyacrylic acid, polysulfonic acid, polypropylene hydrazine Amine and triethylamine.

More specifically, a polymer copolymer or a block copolymer may be a polyoxyethylene-polyoxyethylene block copolymer or a selected from the group consisting of polyoxyethylene glycol, polyoxyethylene-polyoxypropylene alkyl ether, Polyoxyethylene-polyoxypropylene monoalkyl ether, polyoxyethylene-polyoxypropylene alkyl copolymer, polyoxyethylene tallow amine, polyoxyethylene oleylamine, polyoxyethylene octadecylamine, polyoxyethylene twelve One or more substances of a group consisting of a base amine, a polyoxyethylene sorbitol ether, a polyoxyethylene octyl ether, and a polyoxyethylene glyceryl ether, and the present invention can mix a polyacrylic acid and a polystyrene sulfonic acid in an organic polymer. use.

As described above, the organic polymer forms micelles or anti-microcells in the solvent. In this case, the present invention does not particularly limit the kind of the solvent, and can be selected depending on the characteristics of the organic polymer. Specifically, as the solvent, ethanol, glycol ester, ketone or a mixed solvent thereof can be used. The above alcohol may be methanol, ethyl alcohol or isopropanol, and the ethylene glycol ether may be methyl cellosolve or ethyl cellosolve, and the ketone may be methyl ethyl ketone. (methyl ethyl ketone) and methyl isobutyl ketone.

Further, the present invention does not particularly limit the content of the above organic polymer, and may be contained in an amount of 1 to 50 parts by weight based on 100 parts by weight of the solvent. It is easy to form a microcell or an anti-microcell in the above content range, and the dispersibility is also excellent.

The shell in the present invention is formed of a decane compound and an aluminum precursor, and specifically, a decane compound and an aluminum precursor are added to a solvent in which a core composed of a microcell or an antimicrocell of the organic polymer is formed.

The above decane compound can be easily combined with an organic polymer forming a template core. The combination can be carried out by the well-known Stober method (Werner, 1968) in the art, and the shell is prepared by a sol-gel process according to the above Stober method, and is hydrolyzed and polycondensed by passing through an acidic solution or an alkaline solution contained in a solvent. Synthetic way to make a stable shell.

The above decane compound can be represented by the following Chemical Formula 1.

Here, R1, R2, R3 and R4 may each independently be an alkyl group, an alkoxy group, a phenyl group, a vinyl group, a halogen group, an epoxy group, a glycidoxy group, an amino group or a thio group. Specifically, the decane compound can be used without limitation, such as alkoxy decane, chlorodecane, bromodecane, alkyl decane, etc., more specifically, tetramethoxy decane, tetraethoxy decane, or tetrakis. Propoxydecane, methyltrimethoxydecane, dimethyldimethoxydecane, phenyltrimethoxydecane, diphenyldimethoxydecane, methyltriethoxydecane, dimethyldiethyl Oxydecane, phenyltriethoxynonane, diphenylphosphonium ethoxy decane, isobutyl trimethoxy decane, vinyl trimethoxy decane, vinyl triethoxy decane, vinyl tris (β- Methoxyethoxy)decane, 3,3,3-trifluoropropyltrimethoxydecane, methyl-3,3,3-trifluoropropyldimethoxydecane, β-(3,4- Epoxycyclohexyl)ethyltrimethoxydecane, γ-glycidoxytripropyltrimethoxydecane, γ-glycidoxypropylmethyldiethoxydecane, γ-glycidoxy Base propyl Triethoxy decane, γ-methyl propylene methoxypropyl methyl dimethoxy decane, γ-methyl propylene methoxypropyl trimethoxy decane, γ-methyl propylene oxiranyl methyl di Oxydecane, γ-methacryloxypropyltriethoxydecane, N-β(aminoethyl)-γ-aminopropylmethyldimethoxydecane, N-β(aminoethyl)- γ-Aminopropyltrimethoxydecane, N-β(aminoethyl)-γ-aminopropyltriethoxydecane, γ-aminopropyltrimethoxydecane, γ-aminopropyltriethoxydecane , N-phenyl-γ-aminopropyltrimethoxydecane, γ-mercaptopropyltrimethoxydecane, allyloxypropyltrimethoxysilane, trimethylstanol, methyltrichloro Decane, methyldichlorodecane, dimethyldichlorodecane, trimethylchlorodecane, phenyltrichlorodecane, diphenyldichlorodecane, vinyltrichlorodecane, trimethylbromodecane and diethyloxane One or more compounds of the group formed.

The above aluminum precursor may be an organic salt of aluminum or an aluminum alkoxide. The aluminum precursor is used as a component forming a shell, and a part of the alkaline aqueous solution described later is eluted, and micropores are formed in the shell to easily elute the nuclear substance. The type of the aluminum precursor is not particularly limited in the present invention, and an organic salt of aluminum or aluminum alkoxide may be used.

The above aluminum gallate shell may contain X moles of Si element and Y mole of Al element, and the above X/Y molar ratio is 7 to 15. When the X/Y molar ratio is less than 7, the aluminum content is high and the core particles are easily eluted. However, since the micropores on the surface of the shell cannot form a complete hollow type, the strength of the particles is lowered, and high-density hollow particles cannot be prepared, and The aluminum which cannot be eluted on the shell particles causes an increase in the refractive index and cannot be applied to a member requiring a low refractive index. Acidic aqueous solution or alkaline water when the X/Y molar ratio exceeds 15 The aluminum content in the solution is small, and it is not only impossible to remove the aluminum on the surface of the shell particles, but also to completely remove the core particles, so that the refractive index is increased and the haze becomes large when the film is formed.

The step of forming the hollow type aluminum niobate particles causes the core-shell particles to react with the alkaline aqueous solution or the acidic aqueous solution to form micropores on the shell, and at the same time, the core is removed to form hollow type aluminum niobate particles.

The above-described decane compound and the aluminum precursor and the host material described above are combined to form a shell containing a composite precursor of aluminum oxide and cerium oxide, thereby preparing core-shell particles. The core shell particles prepared above are reacted with an aqueous alkaline solution or an acidic aqueous solution to remove a part of the aluminum oxide in the oxide of the composite component of aluminum and cerium oxide constituting the shell and form micropores on the shell.

In this case, the present invention does not particularly limit the kind of the alkaline aqueous solution or the acidic aqueous solution to be used. Specifically, the alkaline aqueous solution may be sodium hydroxide, ammonium hydroxide, potassium hydroxide, hydroxyphosphate or a mixed solution thereof, and is acidic. As the aqueous solution, hydrochloric acid, nitric acid, sulfuric acid, acetic acid or a mixed solution thereof can be used.

The micropores thus formed allow the organic polymer in a dissolved state to smoothly enter and exit, so that the organic polymer inside the shell can be removed by a simple washing step. The organic polymer (nuclear material) inside the shell is dissolved by the above washing, and the dissolved organic polymer can be discharged to the outside through the micropores of the shell previously formed by the alkaline aqueous solution or the acidic aqueous solution.

Here, as the solvent for washing, distilled water, alcohol, glycol, ethylene glycol ether or a mixed solvent thereof may be used. The above alcohol can Using methanol, ethyl alcohol and isopropanol, ethylene glycol, propylene glycol and xylene glycol can be used for glycol, and ethyl acesulfame and acesulfame can be used for ethylene glycol ether. Su.

The step of performing the hydrothermal reaction is a step of hydrothermally reacting the density of the hollow type aluminum niobate particles, and the microparticles having a hollow form are used as an optical coating agent. External organic matter is allowed to intrude into the cavity and it is also necessary to maintain scratch resistance and adhesion. For this reason, the formed shell cannot be formed with pores and is formed at a high density. For this reason, the density of the above hollow type aluminum niobate particles can be increased by a hydrothermal reaction.

The hydrothermal reaction step described above can be carried out at a temperature of from 160 to 250 ° C, and in particular, at a temperature of from 160 to 200 ° C. The above hydrothermal reaction step cannot obtain a desired high density at a low temperature of less than 160 ° C, and thus is difficult to be used as a material for physical physical properties and transmittance increase rate (ΔT%), refractive index, reflection, etc., which require scratch resistance. A display, a lens, and the like having a low reflection characteristic exhibited by a low refractive index such as Haze.

The above hollow type aluminum niobate nanoparticles may have an average particle size of 10 to 300 nm, and the above shell thickness may be 5 to 15 nm. It is excellent in low refractive effect and transparency in the above particle range. In particular, the above hollow type aluminum silicate nanoparticles may have an average particle size of 10 to 100 nm. When the particle size exceeds 100 nm, coating and matrix lamination are opaque due to light scattering. When the particle size is less than 10 nm, it is difficult to expect a low refractive effect due to hollowness. Moreover, the hollow ratio of the hollow type aluminum niobate particles may be 50 to 95%. It is easy to remove the core when preparing the particles in the above range.

The above hollow type aluminum oxide-tellurate particles can contain silica and aluminum oxide in an amount of 0.1 to 30% by weight. In the above content range, the physical properties of the particles are excellent. Moreover, the above shell may form micropores. When particles are prepared through the above micropores, the nuclear material can be easily dissolved out of the shell and made into hollow particles.

The composition for forming a film according to the present invention comprises the above hollow type aluminum niobate particles. The present invention does not particularly limit the kinds of components constituting the above-mentioned composition for forming a film, and in addition to the hollow type aluminum oxide-tellurate particles prepared by the present invention, it is also possible to use those generally used in the art. The composition of the film forming composition.

The antireflection film according to the present invention comprises a transparent film coated by the above composition for forming a film. The hollow type aluminum niobate particles according to the present invention have excellent low reflectance characteristics, and thus can be easily used as a material of a film or the like. In particular, the antireflection film has a characteristic that the penetration increase rate is at least 3%, the refractive index is 1.31 or less, the reflectance is 1.5 or less, and the Haze is 1 or less. Therefore, the antireflection film can be used for a display panel requiring low refraction and high transparency. A coating material for an optical coating material or an AR (Anti-Refraction) material is applied to a BLU (Back Light Unit) material of a high-brightness LCD/PDP, a display polarizer and a prism sheet which require high efficiency.

The specific matters of the process of the present invention will be described below by way of examples and experimental examples.

1. Preparation of hollow aluminum silicate particles

1-1. Core-shell formation example based on aluminum addition amount

Example 1

Pour 0.086 g of PAA (polyacrylic acid), 0.043 g of PSS (polystyrene sulfonic acid) and 1.5 ml of ammonium hydroxide into a 500 ml three-neck round-bottom flask and add 30 ml of ethanol. A core template for hollow type. The above solution was shaken vigorously and 4 ml of 3% isopropyl alumina and 30 ml of ethanol containing TEOS (tetraethoxydecane) were added by a syringe pump to obtain spherical particles containing nuclei. This pellet was reacted with 5% sodium hydroxide, and washed and dried with distilled water and alcohol to obtain Example 1 of an aluminum niobate particle having a hollow form.

Example 2

Example 2 of the aluminum silicate having a hollow form was prepared in the same manner as in Example 1 except that 5 ml of 3% aluminum isopropoxide was used.

Example 3

Example 3 of the aluminum silicate having a hollow form was prepared in the same manner as in Example 1 except that 6 ml of 3% isopropyl alumina was used.

Comparative example 4

Comparative Example 1 of aluminum niobate having a hollow form was prepared in the same manner as in Example 1 except that 3 ml of 3% isopropyl alumina was used.

Comparative Example 5

Comparative Example 5 of aluminum niobate was prepared in the same manner as in Example 1 except that 1 ml of 3% isopropyl alumina was used.

Comparative Example 6

Comparative Example 6 of aluminum niobate particles was prepared in the same manner as in Example 1 except that 3% isopropyl alumina was not added.

Comparative Example 7

Comparative Example 7 of an aluminum niobate particle having a bead chain structure was prepared in the same manner as in Example 1 except that 7 ml of 3% isopropyl alumina was used.

Comparative Example 8

Comparative Example 8 of an aluminum niobate particle having a bead chain structure was prepared in the same manner as in Example 1 except that 10 ml of 3% isopropyl alumina was used.

Comparative Example 9

After preparing a core template in the same manner as in Example 1, the solution was surface-treated with PVP (Poly vinyl pyrrolidone), and 3 ml of 3% isopropyl alumina and 30 ml of ethanol containing TEOS (tetraethoxydecane) were added to obtain a core. Spherical particles. The particles were reacted with 5% sodium hydroxide, and washed and dried with distilled water and alcohol to obtain Comparative Example 9 of aluminum silicate particles having a hollow form.

1-2. Experimental results

Table 1 below shows the Si/Al ratio of the formed core-shell as a function of the amount of aluminum added. Table 2 shows the effect of the amount of aluminum added on the core-shell's hollowness maintenance and shell thickness. . 2 is a TEM photograph of hollow type cerium oxide particles prepared according to Examples and Comparative Examples of the present invention. (a) Example 1, (b) Comparative Example 4, (c) Comparative Example 5, (d) Comparative Example 6, (e) Comparative Example 8, (f) TEM photograph of Comparative Example 9. Transmission electron microscopy (TEM) used JEOL Model JEM-1200EX.

The amount of 3% isopropyl alumina added was 3 ml to 6 ml, and the aluminum silicates formed in Examples 1 to 3 and Comparative Examples 4 and 9 in which the Si/Al ratio was 7 to 16 had about 60 to 100 nm. The left and right particle diameters form a hollow form of fine particles having a shell thickness of 10 to 15 nm.

The degree of uniformity of the shell formed on the surface of the core varies depending on the amount of isopropylidene added. The hollow form is omitted when the addition step is omitted, and the amount of isopropyl alumina is increased to decrease the Si/Al ratio to below 7. At the time, although hollow type particles can be formed, a single dispersed particle cannot be prepared because the degree of aggregation between the particles is relatively serious.

2. High-density reaction of hollow aluminum citrate particles

2-1. Hydrothermal Synthesis of the Prepared Particles

Example 1_H180

After pouring 20 g of the particles of the above Example 1 and 80 g of distilled water, ultrasonic dispersion was carried out by an ultrasonic disperser for 1 hour to obtain an aqueous dispersion of aluminum niobate which was stably dispersed in water. The dispersion was poured into a 1 L hydrothermal reactor and subjected to a reaction at 180 ° C for 10 hours, followed by precipitation and drying to prepare hollow type aluminum niobate particles having an increased shell density.

Example 2_H180

Using the above Example 2 particles, hollow type aluminum niobate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Example 3_H180

Using the above Example 3 particles, hollow type aluminum niobate particles having an increased shell density were prepared in the same manner as in the above Example 1-H180.

Comparative Example 4_H180

Using the above Comparative Example 4 particles, aluminum gallate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 5_H180

Using the above Comparative Example 5 particles, aluminum silicate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 6_H180

Using the above Comparative Example 6 particles, aluminum silicate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 7_H180

Using the above Comparative Example 7 particles, aluminum silicate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 8_H180

Using the above Comparative Example 8 particles, aluminum silicate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 9_H180

Using the above Comparative Example 9 particles, hollow type aluminum niobate particles having an increased shell density were prepared in the same manner as in the above Example 1_H180.

Comparative Example 1_H150

A hollow type aluminum niobate particle having an increased shell density was prepared in the same manner as in the above Example 1_H180 except that the above-mentioned Example 1 particles were used and hydrothermal reaction was carried out at 150 °C.

Comparative Example 1_H130

A hollow type aluminum niobate particle having an increased shell density was prepared in the same manner as in the above Example 1_H180 except that the above-mentioned Example 1 particles were used and hydrothermal reaction was carried out at 130 °C.

Comparative Example 1_H100

In addition to the use of the above-mentioned Example 1 particles and hydrothermal reaction at 100 ° C, hollow type aluminum niobate particles having an increased shell density were prepared in the same manner as in the above Example 1 - H180.

Comparative Example 2_H150

A hollow type aluminum niobate particle having an increased shell density was prepared in the same manner as in the above Example 1_H180 except that the above Example 2 particles were used and hydrothermal reaction was carried out at 150 °C.

Comparative Example 3_H150

A hollow type aluminum niobate particle having an increased shell density was prepared in the same manner as in the above Example 1_H180 except that the above Example 3 particles were used and hydrothermal reaction was carried out at 150 °C.

2-2. Experimental results

Table 3 shows the change in shell density before and after the hydrothermal reaction of Examples 1-3. As shown in Table 3, the high density is carried out in accordance with the hydrothermal reaction.

Table 4 shows the results of examining the hollowness maintenance and the shell thickness after preparing the aluminum niobate particles having an increased shell density by hydrothermal reaction, and Fig. 3 is prepared and densified according to Examples and Comparative Examples of the present invention. TEM photograph of the reacted hollow type cerium oxide particles. (a) Example 1_H180, (b) Comparative Example 4_H180, (c) Comparative Example TEM photographs of 5_H180, (d) Comparative Example 6_H180, (e) Comparative Example 8_H180, and (f) Comparative Example 9_H180.

As shown in the experimental results of Table 4, the above-mentioned Example 1_H180 to Example 3_H180 in which the Si/Al ratio of the aluminum niobate shell was 7 to 15 and hydrothermally reacted at 180 ° C maintained a hollow type and had 8 to 10 nm. Shell thickness. Further, in Comparative Example 1_H150 to Comparative Example 3_H150 in which the aluminum silicate particles of Examples 1 to 3 were hydrothermally reacted at a low temperature of less than 180 ° C, all of them were maintained in a hollow shape and had a shell thickness of 8 to 10 nm.

However, Comparative Example 4 in which the Si/Al ratio of the above aluminum gallate shell was 15.9 was formed as a hollow type before the hydrothermal reaction, and a part of the hollow type was destroyed in the hydrothermal reaction. The degree of uniformity of the shell formed on the surface of the core varies depending on the amount of isopropyl alumina added, and the above aluminum silicate shell When the Si/Al ratio exceeds 15, the hollow type particles can be formed, but it is difficult to maintain the hollowness in the hydrothermal reaction.

3. Preparation of a low-reflection coating film from hollow aluminum silicate particles

3-1. Preparation of reflective coating liquid and coating film

Example 1_H180_3-1

The particles of the above Example 1_H180 were all replaced with ethanol and MIBK to prepare a 10% solid aluminum silicate MIBK dispersion. Adding acid-catalyzed Acryl Silane (KBM-503) hydrolyzate to the dispersion for surface treatment, adding pentaerythritol tetraacrylate (Cytec), photoinitiator using IRGACURE 184 (US) A photocurable coating liquid was prepared by the company. The prepared coating liquid was uniformly applied to the PET film by a layer bar coating method, and then ultraviolet-cured to form a transparent film.

Example 2_H180_3-1

Using the particles of the above Example 2_H180, a transparent film was formed in the same manner as in the above Example 1_H180_3-1.

Example 3_H180_3-1

Using the particles of the above Example 3-H180, a transparent film was formed in the same manner as in the above Example 1_H180_3-1.

Comparative Example 4_H180_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the particles of Comparative Example 4_H180 described above.

Comparative Example 5_H180_3-1

A transparent film was formed by the same method as the above Example 1_H180_3-1 using the particles of Comparative Example 5_H200 described above.

Comparative Example 6_H180_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the particles of Comparative Example 6-H180 described above.

Comparative Example 7_H180_3-1

A transparent film was formed by the same method as the above Example 1_H180_3-1 using the particles of Comparative Example 7_H180 described above.

Comparative Example 8_H180_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the particles of Comparative Example 8_H180 described above.

Comparative Example 9_H180_3-1

A transparent film was formed by the same method as the above Example 1_H180_3-1 by the above-mentioned particles of Comparative Example 9-H180.

Comparative Example 1_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the particles of the particles of Example 1 described above.

Comparative Example 1_H150_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the above Comparative Example 1_H150 particles.

Comparative Example 1_H130_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the above Comparative Example 1_H130 particles.

Comparative Example 1_H100_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the above Comparative Example 1_H100 particles.

Comparative Example 2_H150_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the above Comparative Example 2_H150 particles.

Comparative Example 3_H150_3-1

A transparent film was formed in the same manner as in the above Example 1_H180_3-1 by using the above Comparative Example 3_H150 particles.

3-2. Experimental evaluation method

I. Rate increase rate (ΔT%), the total light transmittance (380 to 1100 nm) of the coated film was measured to measure the difference in transmittance compared to the film (PET film). The transmittance analyzer uses Jasco's J-570 product.

II. In terms of refractive index, the coating liquid is applied to the tantalum wafer and subjected to a hardening process, and the refractive index is obtained by spectral ellipsometry using Ellipso Technology's ellipsometry (200~). 1100 nm) Analysis values were evaluated.

III. In terms of reflectance evaluation, a black film was attached to the back surface of the coating film in order to prevent further reflection of light.

For the analysis of IV. Haze, the coated film was analyzed using an integrating sphere of Jasco's J-570.

V. For the evaluation of adhesion, a 10x10 groove was formed on the coated surface, and a tape was attached, and then the coated surface was peeled off to evaluate whether the coated surface was peeled off, and no peeling was evaluated as ◎, and less than 10 were detached. It was rated as △, and most of the shedding was rated as x.

VI. In terms of scratch resistance evaluation, steel wool (#0000) was scraped back and forth 10 times with 150 g back and forth, and those with less than 5 scratch marks were rated as ◎, and those with less than 20 were rated as △, 20 The above is rated as X.

3-3. Experimental results

Table 5 lists the results of evaluating the transmittance increase rate (ΔT%), refractive index, reflectance, Haze, adhesion, and scratch resistance after forming a transparent film using aluminum niobate particles.

As shown in the experimental results of Table 5, a part of the hollow type or the shell fracture occurred in the comparative example 4_H180_3-1 to the comparative example 5_H180_3-1 in which the Si/Al ratio of the aluminum niobate shell was 15 or more, and the Si/Al ratio. The comparative example 6_H180_3-1 of 7 or less to the comparative example 8_H180_3-1 exhibited a spherical or amorphous microparticle morphology and a part of hollow type or shell failure, amorphous microparticle morphology, etc. after hydrothermal reaction, and the hollow type dioxide was not maintained. The morphology of the crucible causes the transmittance increase rate (ΔT%), the refractive index, the reflectance, and the Haze evaluation result to be not excellent.

As for Comparative Example 1_3-1 in which no hydrothermal synthesis reaction was carried out, and in comparison with Example 1_H180 in which the same hollow type aluminum niobate particles were used and hydrothermal reaction was carried out at 180 ° C, the transmittance increase rate (ΔT%), The refractive index, reflectance, Haze's evaluation, adhesion, and scratch resistance were all unsatisfactory.

In order to use fine particles having a hollow form as an optical coating agent, external organic substances are not allowed to enter the cavities and it is necessary to maintain scratch resistance and adhesion. Therefore, no pore formation can be formed on the formed shell. It must also be formed at a high density.

As for Comparative Example 1_3-1 in which the hydrothermal synthesis reaction was not carried out, sufficient density was not formed and all the unsatisfactory results were obtained in all the evaluations. Further, Comparative Example 1_H150_3-1 to Comparative Example 3_H150_3-1 in which the hydrothermal reaction was carried out at a low temperature of 150 ° C or lower did not form a sufficient density, and a result similar to Comparative Example 1_3-1 was obtained.

Comparative Example 9_H180_3-1 is an experimental example in which a polymer electrolyte of PVP (Poly Vinyl Pirrolidone) was added and then subjected to surface treatment, and a polymer electrolyte was added to have a strong positive ion to maintain a hollow state, but a hollow type of cerium oxide was prepared. Since the post-ion ions remain and the surface treatment or the like cannot be further performed, the solvent is not replaced and the transparent film is not formed when the solvent is replaced and the binder is added.

On the contrary, a transparent film formed of the aluminum niobate particles of Example 1_H180_3-1 to Example 3_H200_3-1 in which the Si/Al ratio of the above aluminum gallate shell was 7 to 15 and hydrothermal reaction was carried out at 180 °C. Then, the transmittance increase rate (ΔT%) was 3% or more, the refractive index was 1.31 or less, the reflectance was 1.5 or less, Haze was 1 or less, and the adhesion and scratch resistance were all excellent.

As described above, the antireflection film of the present invention conforms to the characteristics required for the display material, and thus can be used for display panels requiring low refraction and high penetration, optical coating materials, and AR (Anti-Refraction) materials. A coating layer, a BLU (Back light unit) material for a high-brightness LCD/PDP, a display polarizer and a prism sheet which require high efficiency.

According to the hollow type aluminum niobate particle of the present invention, after forming an aluminum niobate shell on a core composed of an organic polymer, the organic polymer inside the shell is removed without undergoing a high-temperature sintering process, and low cohesion, excellent dispersibility, and water are obtained. Excellent density due to thermal reaction.

Moreover, the method for preparing hollow type aluminum niobate particles according to the present invention forms a negative charge during the formation of the composite oxide in the reaction of the aluminum precursor and the ceria precursor to form a shell without further nuclear preparation. The surface treatment can also form a uniform shell, and under the high-density reaction, the shell is not damaged to form uniform hollow particles.

The technical idea of the present invention described above is not limited to the foregoing embodiments and the drawings, and those skilled in the art having the technical idea of the present invention know that various substitutions and modifications can be implemented without departing from the technical idea of the present invention. And modify.

Claims (12)

A method for preparing hollow type aluminum niobate particles, comprising the steps of: reacting a decane compound and an aluminum precursor on a template core composed of a micronucleus or a reverse micel of an organic polymer; Producing core-shell particles forming an aluminosilicate shell; reacting the core-shell particles with an aqueous alkaline solution or an acidic aqueous solution to form micropores on the shell, and simultaneously removing the core to form a hollow type Aluminosilicate particles; and a hydrothermal reaction for increasing the density of the hollow type aluminum niobate particles; wherein the aluminum gallate shell contains X moles of Si element and Y mole of Al element, and the X/Y molar ratio is 7 to 15. The method for producing hollow type aluminum niobate particles according to claim 1, wherein the hydrothermal reaction step is carried out at a temperature of from 160 to 200 °C. The method for producing hollow type aluminum niobate particles according to claim 1, wherein the hollow type aluminum niobate nanoparticles have an average particle size of 10 to 300 nm, and the shell thickness is 5 to 15 nm. The method for producing hollow type aluminum niobate particles according to claim 1, wherein the organic polymer is a copolymer or a block copolymer, and the copolymer or block copolymer comprises a selected from the group consisting of polyoxyethylene and poly Oxyethylene glycol, polyoxypropylene alkyl ether, polyoxypropylene monoalkyl ether, polyoxypropylene alkyl, Polyoxyethylene tallow amine, polyoxyethylene oleylamine, polyoxyethylene octadecylamine, polyoxyethylene dodecylamine, polyoxyethylene sorbitol ether, polyoxyethylene octyl ether, polyoxyethylene glyceryl ether, polyacrylic acid A polymer of a group consisting of polysulfonic acid, polyacrylamide, and triethylamine. The method for producing hollow type aluminum niobate particles according to claim 1, wherein the decane compound is represented by the following Chemical Formula 1, (In the above formula, R1, R2, R3 and R4 are each independently an alkyl group, an alkoxy group, a phenyl group, a vinyl group, a halogen group, an epoxy group, a glycidoxy group, an amino group or a thio group). The method for producing hollow type aluminum niobate particles according to claim 1, wherein the aluminum precursor is an organic salt of aluminum or aluminum alkoxide. The method for preparing hollow type aluminum niobate particles according to claim 1, wherein the alkaline aqueous solution is sodium hydroxide, ammonium hydroxide, potassium hydroxide, hydroxyphosphate or a mixed solution thereof. The above acidic aqueous solution is hydrochloric acid, nitric acid, sulfuric acid, acetic acid or a mixed solution thereof. A hollow type aluminum silicate particle prepared by the preparation method described in claim 1 and comprising: a hollow core; and a shell containing cerium oxide and aluminum oxide, wherein the aluminum silicate shell comprises Si The element X mole and the Al element Y mole, and the X/Y molar ratio is 7 to 15. The hollow type aluminum niobate particles according to claim 8, wherein the hollow type aluminum niobate nanoparticles have an average particle size of 10 to 300 nm, and the shell thickness is 5 to 15 nm. A composition for forming a film, comprising the hollow type aluminum niobate particles according to item 8 of the patent application. An antireflection film comprising a transparent film coated with a composition for forming a film as described in claim 10 of the patent application. The antireflection film according to claim 11, wherein the antireflection film has a transmittance of at least 3%, a refractive index of 1.31 or less, a reflectance of 1.5 or less, and a Haze of 1 or less.