KR100829344B1 - Method for preparing of photochromic dyes-polymer microparticles encapsulated inorganic matter - Google Patents

Abstract

The present invention relates to a method for preparing inorganic encapsulated photochromic dye-polymer integrated microparticles, and more particularly, to stabilized silica particles by using a pickering emulsion containing silica particles and a comonomer having high bonding strength with the silica particles. After preparing the photochromic dye-polymer integrated microparticles, the photochromic dye prepared by forming an inorganic layer on the surface of the photochromic dye-polymer integrated microparticles and the inorganic core covering the surface of the polymer core layer A method for producing photochromic dye-polymerized microparticles encapsulated with a layered inorganic material.

According to the present invention, there is an effect of providing photochromic dye-polymer-integrated microparticles encapsulated with minerals that improve photochromic speed and maintain stable properties against ultraviolet rays and free radicals and at the same time have excellent oxygen barrier properties.

Photochromic dyes, radical polymerization, miniemulsions, sol-gels, adsorption, pickering emulsions

Description

METHODS FOR PREPARING OF PHOTOCHROMIC DYES-POLYMER MICROPARTICLES ENCAPSULATED INORGANIC MATTER}

1 is an SEM image of photochromic dye-polymerized microparticles encapsulated with an inorganic material prepared according to one embodiment of the present invention.

Figure 2 is a diagram showing the structure of the photochromic dye-polymer integrated microparticles encapsulated with inorganic prepared according to the present invention.

The present invention relates to a method for preparing photochromic dye-polymerized microparticles encapsulated with minerals. More specifically, the present invention relates to a method for preparing photochromic dye-integrated microparticles. A method for producing encapsulated photochromic dye-polymer integrated microparticles.

Photochromic material absorbs light energy of a certain wavelength and changes its molecular structure. In this state, the color of the externally changed compound is changed. When the energy applied to this material is stopped, it reversibly returns to the previous molecular structure. Have.

When the photochromic material is composed of inorganic materials such as metal oxides, alkaline earth metals, mercury compounds, and transition metal compounds, it is very stable to external environments such as ultraviolet light, oxygen, and solvents, but it is difficult to utilize because the processing is very difficult. there was. On the other hand, organic photochromic dyes composed of benzopyrans, naphthopyrans, spiropyrans, spirooxazines, pulzimids, diarylethenes, and azo compounds are easily dissolved or powdered in a solvent, but are light or oxygen. It is unstable due to acid, organic solvent, etc. and has a problem of insufficient durability.

An example of commercializing such a photochromic dye is a photochromic spectacle lens. Under the bright sun, the lens is discolored by some wavelengths of sunlight (usually ultraviolet rays), absorbing certain wavelengths passing through the lens, blocking excess light, protecting the eyes, and returning to the original color indoors to brighten the view. I am equipped with a function to do it. As such, most products using photochromic need long durability to secure stability of dye to external exposure in order to maintain fast discoloration speed and product value.

The disadvantage of the photochromic dye is that the side reactions of the chemical molecular structure are destroyed by external environmental factors and the discoloration by light disappears as described above. It is known that the cause of such side reactions is an oxidation reaction by free radicals or oxygen, a hydrogen displacement reaction, a photochemical hydrogen displacement reaction by ultraviolet rays, or the like.

In order to suppress or delay such side reactions, various conventional methods have been proposed.

Firstly, stabilizers are mixed with photochromic dyes simultaneously. The photochromic dye is made into an application by applying a product in a form dispersed in a dispersion medium on a support or mixing the inside of the support. In order for the dispersed photochromic dye to react free radicals that cause side reactions before the photochromic dyes, a substance such as an antioxidant is added to the dispersion medium, or ultraviolet rays having high energy, which is one of the causes of the production of free radicals, It is a method of improving the stability of the photochromic dye by adding a UV absorber that absorbs and converts into a low energy. However, there is a problem that the above method does not prevent side reactions caused by oxygen or acid.

Second, the photochromic dye is physically blocked by free radicals and the like, and the photochromic dye is tightly wrapped using a polymer or the like.

As an example, U.S. Patent No. 4,166,043 discloses polymer particles by dispersing a solution in which photochromic dyes are dissolved with methylene chloride together with polymethylmethacrylate in ethyl alcohol, or making cellulose acetate and photochromic dyes a common solvent, chloroform. Disclosed is a method of obtaining a particle by pulverizing a solid formed by dissolving in a solvent and then removing the solvent to obtain a particle, and sputtering the surface of the particle with silicon oxide or titanium oxide to block free radicals to increase the stability of the photochromic dye. Doing. However, this technique has the problem that only a good solubility material (typically, the solvent of the photochromic dye is very limited) can be used in a particular solvent, and the process is very complicated and the surface of the particle can not be tightly protected, and such as ultraviolet rays. There is a problem that there is a limit in the provision of stability to light.

U.S. Patent No. 5,017,225 discloses a method for encapsulating a photochromic dye using coacervation using gelatin. In particular, the stability of the photochromic dye can be improved by mixing the antioxidant and the ultraviolet absorber together in the microcapule, but the size of the microcapsules that can be obtained using this method is required to have a transparency of several μm. Its use is limited, and as time passes, compounds added for stabilization are separated from photochromic dyes by bleeding or blooming, thereby degrading stabilization efficiency.

In addition, PCT / FR2002 / 00116 and U. S. Patent No. 6,740, 699 encapsulate in an aqueous emulsion by minimization polymerization of acrylic, methacryl monomers and photochromic dyes, but together with olefinic compounds such as methylbutenol and cyclohexene. A method for producing a stable emulsion in which the concentration of the photochromic dye does not change for several months by mixing and polymerizing is disclosed. However, in the present invention, the monomer is limited to an acrylic monomer such as butyl acrylate, and the stabilizer may also be used only as an olefin stabilizer having a specific structure. It is expected that the concentration of is reduced, thereby accelerating side reactions that change the material.

On the other hand, various methods have been proposed as a method of wrapping the polymer particles with inorganic materials. However, since the affinity between organic materials such as polymers and silica is not so high, cationic polymer particles exhibiting cationic properties for enhancing affinity with silica precursors having negative charges, or organic materials as coupling agents with inorganic materials on the surface of polymer particles. There are several reports that treating a compound having a silicon atom bonded to it can increase affinity with inorganic substances such as silica.

Specifically, examples of the introduction of minerals using a polymer as a template include Chem. Commun. ((2003), p. 1010-1011) prepared particles having a functional group of -NH ₂ / -COOH or -NH ₂ when polystyrene particles of 0.1 to 1 탆 were prepared through emulsion-free emulsion polymerization. After that, the latex particles are placed in sodium silicate to precipitate silicic acid on the particle surface, and then converted into silica to wrap the polystyrene particle surface with silica.

합성법으로 SiO₂로 합성하면서 폴리비닐피롤리돈 위에 실리카 층이 형성되도록 유도하여 고분자 입자를 실리카로 감싸는 방법에 대하여 기재하고 있다. Langmuir ((2003), 19, p. 6693 to 6700) prepared polystyrene particles by emulsion-free emulsion polymerization, adsorbed polyvinylpyrrolidone on the surface of the polystyrene particles, and then silica of the polyvinylpyrrolidone. Tetraethoxysilane can be

A method of encapsulating a polymer particle in silica by inducing a silica layer to be formed on polyvinylpyrrolidone while synthesizing with SiO ₂ by a synthesis method is described.

합성법을 실시하는 방법에 대하여 기재하고 있다. 구체적으로, MPS로 처리된 입자는 입자 표면에 실라놀기가 형성되고, 그 실라놀기와 테트라에톡시실란으로부터 형성되는 실리실산 사이의 축합반응에 의해서 실리카가 형성되는 수정보완된

합성법으로 폴리스티렌 입자 주위를 실리카로 감싸는 방법에 대하여 기재하고 있다.In addition, Macromolecules ((2002), 35, p. 6185-6191), Macromolecules ((2001), 34, p.5737-5739), Chem. Mater. ((2002), 14, p. 1325 to 1331) prepared polystyrene particles having a surface treated with Si-OH using methoxypropyltrimethoxysilane (hereinafter referred to as MPS). With tetraethoxysilane

It describes about the method of performing a synthesis method. Specifically, the particles treated with MPS have silanol groups formed on the surface of the particles, and silica is formed by condensation reaction between silanol groups and silicic acid formed from tetraethoxysilane.

It describes the method of wrapping around a polystyrene particle with silica by the synthesis method.

However, since the method for preparing the polymer core layer-inorganic outer layer particles as described above should use the polymer particles prepared by the emulsion polymerization method, it is impossible to include the photochromic dye in the polymer particles, and the photochromic dye is included. Even if the particles are used, there is a problem in the procedure that the inorganic secondary particles are produced in the step of wrapping the inorganic material. If the concentration of the polymer template is too high, the distance between the particles is close, so that the minerals are bonded to each other so that the whole system becomes one. There is a problem.

In order to solve the problems of the prior art as described above, the present invention provides a method for producing photochromic dye-polymer-integrated microparticles encapsulated with an inorganic material that improves photochromic performance, is stable to ultraviolet rays and free radicals, and has excellent oxygen barrier properties. It aims to provide.

It is another object of the present invention to provide an inorganic encapsulated photochromic dye-polymer-integrated microparticles prepared by the above production method.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention

a) preparing a Pickering mini-emulsion by mixing a monomer, silica nanoparticles, a comonomer having affinity with the silica nanoparticles, and a photochromic dye;

b) polymerizing the Pickering mini-emulsion to produce photochromic dye-polymer-integrated microparticles in which a photochromic dye is embedded in a polymer and stabilized with silica; And

c) forming an inorganic layer on the surface of the photochromic dye-polymer integrated microparticles;

It provides a method for producing a photochromic dye-polymer integrated microparticles encapsulated with an inorganic, characterized in that consisting of.

The present invention also provides a photochromic dye-polymer integrated microparticles encapsulated with an inorganic material prepared by the above production method.

Hereinafter, the present invention will be described in detail.

In order to ensure fast photochromic properties of the photochromic dye, the photochromic dye should be mixed with a material which is amorphous and has a free space in which the structure of the dye can be converted. Typical of such materials are amorphous polymeric materials. Therefore, the present inventors prepared a polymer core layer wrapped with an inorganic material on the surface of the polymer particles in which the photochromic dye is dispersed, and then formed an inorganic layer on the surface of the polymer core layer to encapsulate the inorganic particles in the photochromic dye-polymer integrated particles. As a result of the preparation, it was confirmed that it has fast photochromic properties and is stable to ultraviolet rays and free radicals and has excellent oxygen barrier property, and completed the present invention based on this.

The manufacturing method of the photochromic dye-polymer integrated microparticles | fine-particles encapsulated with the mineral of this invention is characterized by using the Pickering emulsion method in order to solve the stabilization problem of a photochromic dye.

Pickering emulsion is a phenomenon discovered by Pickering and refers to a form in which a liquid or solid emulsion is stabilized with minerals and dispersed as a fine particle in a liquid medium (J. Chem. Soc. Chem. Comm. (1907). , 91, p. 2001-2003).

In the present invention, by using the Pickering emulsion method to stabilize the mini-emulsion containing photochromic material with nano-silica particles and then polymerized to prepare a photochromic dye-containing polymer microparticles wrapped with an inorganic material first, the outside of the polymer microparticles The sol-gel method fills the empty space between the silica unit particles adsorbed on the surface with a sol-gel method to form an inorganic layer surrounding the photochromic dye-containing polymer microparticles so that the polymer containing the photochromic dye By removing the part which can come into contact with the photoresist, inorganic encapsulated photochromic dye-polymer-integrated microparticles can be prepared that can ultimately maintain photochromic speed and ensure stability to external oxygen.

According to the production method of the present invention using the pickering emulsion as described above, after preparing the particles having the outer wall of the silica having a dense structure around the photochromic dye-polymer integrated fine particles, the sol-gel method using alkoxy metal By filling the empty space between the silica particles on the surface of the fine particles, it is possible to produce a photochromic dye-polymer integrated microparticles wrapped with silica nanoparticles of step 1 and step 2.

The manufacturing method of the photochromic dye-polymer integrated microparticles | fine-particles encapsulated with the mineral of this invention is demonstrated in detail as follows.

a) preparing a pickering mini emulsion

This step is to prepare a Pickering mini-emulsion by mixing monomers, silica nanoparticles, comonomers and photochromic dyes having affinity with the silica nanoparticles.

The Pickering mini-emulsion can be prepared by homogenizing a monomer, silica nanoparticles, comonomers, photochromic dyes, preparative water, initiators, photochromic dye stabilizers and deionized water and the pH adjusting buffer as needed.

As the monomer, a compound having an unsaturated double bond in which a polymerization reaction proceeds as a free radical may be used alone or in combination of two or more thereof.

The silica nanoparticles may be used having a particle size of 5 to 30 nm, it is preferable to use a dispersion of water by weight of silica solid content of 1 to 70%. The content of the silica nanoparticles may be included in an amount of 0.05 to 20 parts by weight based on 100 parts by weight of the monomer.

As the comonomer, a compound capable of free radical polymerization among materials having affinity with the silica nanoparticles may be used, and vinyl aromatic, aliphatic amines such as 4-vinylpyridine, vinyl imidazole, diallyl methylammonium chloride, or the like alone or It can mix and use 2 or more types. The content of the comonomer is preferably included in 0.1 to 100 parts by weight based on 100 parts by weight of the monomer.

The comonomer stabilizes the miniemulsion by making an electrostatic bond with the silica nanoparticles, and the bond is maintained even after the polymerization. In addition, the comonomer can control the discoloration rate of the photochromic dye through control of the glass transition temperature in addition to giving affinity with silica, it is possible to add two or more comonomers according to the purpose, the monomers mentioned above It can also be used as comonomer.

As the photochromic dye, benzopyran, naphthopyran, spiropyran, spiro oxazine, pulzimid, diarylethene or azo compound-based photochromic compound can be used. The photochromic dye may be included in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the monomer.

The hydrophobic agent (强 疏 水劑, ultrahydrophobe) is dissolved in water at 5 ℃ 10 ~ ⁶ g / kg or less at 25 ℃, carbon atoms of 12 to 20 aliphatic alcohols, acrylate consisting of alkyl groups of 12 to 20 carbon atoms, carbon number 12 to 20 alkyl mercaptans, organic substances, fluorinated alkanes, silicone oil compounds, natural oils or synthetic oils and the like may be used alone or in combination of two or more thereof. The content of the hydrophobic agent may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the monomer.

As the initiator, it is preferable to use an initiator that generates free radicals. Specifically, a redox initiator composed of a combination of a peroxide compound initiator, an azo compound initiator, or a redox compound may be used alone or in combination of two or more thereof. Can be used. The content of the initiator is preferably included in 0.01 to 0.3 parts by weight based on 100 parts by weight of the monomer.

The photochromic dye stabilizer may be a compound such as benzophenone-based, benzotriazole-based or hindered amine-based, the content is preferably included in 0.1 to 20 parts by weight based on 100 parts by weight of the monomer.

The deionized water is preferably included in 100 to 800 parts by weight based on 100 parts by weight of the monomer.

In addition, the pH control buffer that can be used as needed may be used a conventional buffer commonly used in the art such as phosphate, carbonate, etc., the content is contained in 0.01 to 5 parts by weight based on 100 parts by weight of monomer It is good to be.

Such components are uniformly mixed with a mechanical mixer (pre-emulsion) and then emulsified using a microfludizer, Gaulin homogenizer, ultrasonic homogenizer, etc. As homogenous as possible.

b) preparing photochromic dye-polymer fine particles

This step is to polymerize the pickering mini-emulsion of a) to produce photochromic dye-polymer integrated microparticles in which the photochromic dye is contained in the polymer and stabilized with silica.

The pickering mini-emulsion of step a) prepared by homogenization may be put into a polymerization reactor and polymerized at 50 to 100 ° C. to prepare spherical photochromic dye-polymer integrated microparticles.

c) forming an inorganic layer

This step is a step of forming an inorganic layer surrounding the photochromic dye-polymer integrated microparticles by completely filling the empty space between the silica particles surrounding the surface of the photochromic dye-polymer integrated microparticles of b).

The inorganic layer may be prepared by stirring the photochromic dye-polymer integrated particles, alkoxy metal, ammonium base or hydrochloric acid and deionized water at room temperature, if necessary, wrapped with silica nanoparticles of step b). Hydrolyzed alkoxy metals produced from alkoxy metals have been reported to have a very high affinity with silica particles, which can be used to fill the void space between adsorbed silica particles.

The alkoxy metal is used in the synthesis to fill the empty space between the silica particles, and may be used an inorganic oxide consisting of Ti, Zr Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W and In. have. The alkoxy metal content may be included in an amount of 0.1 to 300 parts by weight based on 100 parts by weight of the photochromic dye-polymer integrated particles wrapped with the silica nanoparticles of step b).

The alkoxy metal may be temporarily added, continuously or partially injected in the presence of photochromic dye-polymer integrated microparticles, ammonium base or hydrochloric acid, deionized water and alcohol, in particular continuous or split injection to produce inorganic secondary particles. It is preferable in suppressing.

The amount of ammonium base or hydrochloric acid may be included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the photochromic dye-polymer integrated particles wrapped with the silica nanoparticles of step b).

In addition, the deionized water that can be used as necessary may be included in an amount of 0.1 to 500 parts by weight based on 100 parts by weight of the photochromic dye-polymer integrated particles wrapped with silica nanoparticles of step b).

As described above, minerals are formed on the surface of the photochromic dye-polymer-integrated microparticles so that the photochromic dye-polymer-integrated photochromic dye-polymers are encapsulated as the final inorganics in which the particulate core and the inorganic outer layer are integrated. The fine particles may then be further subjected to a hydrothermal reaction. Through this additional reaction step it is possible to compact the structure of the inorganic layer.

The hydrothermal reaction step is preferably carried out for 3 to 200 hours at 80 to 300 ℃, through this step to make the inorganic structure more dense can increase the degree of crosslinking.

The present invention provides an inorganic encapsulated photochromic dye-polymer integrated microparticles, which is produced by the above production method.

The photochromic dye-polymerized microparticles encapsulated with the inorganic material include a polymer core layer in which a photochromic dye is dispersed and an inorganic layer surrounding the polymer core layer, and have a structure as shown in FIG. 2. According to Figure 2, the inorganic color encapsulated photochromic dye-polymer integrated microparticles of the present invention is adsorbed silica nanoparticles on the surface of the polymer integrated microparticle core layer in which the photochromic dye is dispersed by the Pickering mini-emulsion method including silica nanoparticles To form photochromic dye-polymer-integrated microparticles stabilized with silica particles, and then form an inorganic layer by filling pores on the surface of the microparticles with alkoxy metal, wherein the polymer core layer and photopolymer dye are dispersed. The structure which consists of an inorganic layer which wraps the surface of a layer is shown.

In the inorganic encapsulated photochromic dye-polymer integrated microparticles, the average particle diameter is not particularly limited, and when used for transparent purposes, it is more effective that the average particle diameter is shorter than the wavelength of visible light within 50 nm.

It is preferable that the photochromic dye-polymer integrated microparticles | fine-particles encapsulated with the said inorganic layer are 20-100 nm in thickness of an inorganic layer. In the case of the thickness range is excellent in physical properties, there is an effect suitable for use in optical applications.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

EXAMPLE

Example 1

100 parts by weight of styrene, 20 parts by weight of 4-vinylpyridine, 0.05 parts by weight of initiator V65, 5.0 parts by weight of hexadecane, 0.1 part by weight of a benzotriazole stabilizer, photochromic dye (naphthoxazine, which appears blue when exposed to ultraviolet light) 5 After mixing the parts by weight, 3 parts by weight of the aqueous dispersion of silica nanoparticles charged with anion having a particle size of 22 nm and a solid content of 30% were dissolved in 300 parts by weight of deionized water, mixed in an aqueous solution, and then treated with an ultrasonic grinder for 5 minutes. After making the mullion, it was slowly stirred in a batch reactor and polymerized by heating at a reaction temperature of 60 to 90 ° C. for 5 hours.

1.0 g of ammonia water (17%) was added to 20 g of the photochromic dye-polymer integrated fine particle solution stabilized with the silica, while stirring, 1 g of tetraethoxysilane was added over 12 hours to encapsulate it with a mineral having a dense structure. One photochromic dye-polymer integrated microparticle was prepared. SEM pictures of the prepared poly (styrene-co-4-vinylpyridine) particles wrapped with silica are shown in FIG. 1, and the physical properties thereof are shown in Table 1 below.

According to FIG. 1, it was confirmed that the inorganic layer was formed to tightly surround the surface of the polymer-integrated microparticles in which the photochromic dye was dispersed.

Example 2

100 parts by weight of styrene, 20 parts by weight of 4-vinylpyridine, 0.05 parts by weight of initiator V65, 5.0 parts by weight of hexadecane, 3 parts by weight of a benzotriazole stabilizer, photochromic dye (naphthoxazine, which appears blue when exposed to ultraviolet light) 5 After mixing parts by weight, 2 parts by weight of an aqueous dispersion of silica nanoparticles charged with anion having a particle size of 15 nm and a solid content of 30% was dissolved in 300 parts by weight of deionized water, mixed in an aqueous solution, and then treated with an ultrasonic grinder for 5 minutes to minimize the emulsion. After the preparation, it was slowly stirred in a batch reactor and heated at 60 to 90 ° C. for 5 hours to polymerize.

1.0 g of ammonia water (17%) was added to 20 g of the photochromic dye-polymer integrated microparticles solution stabilized with the silica, while stirring, 1 g of tetraethoxysilane was added over 12 hours to encapsulate it with a mineral having a dense structure. Poly (styrene-co-4-vinylpyridine) particles wrapped with silica, which is a photochromic dye-polymer integrated particulate, were prepared.

Example 3

100 parts by weight of methyl methacrylate, 20 parts by weight of 1-vinylimidazole, 0.05 parts by weight of initiator V65, 5.0 parts by weight of hexadecane, 0.1 parts by weight of a benzotriazole stabilizer, photochromic dye (a blue color when exposed to ultraviolet rays) Naphthooxazine) 5 parts by weight was mixed, and then 3 parts by weight of an aqueous solution of silica nanoparticles charged with anions having a particle size of 22 nm and a solid content of 30% were dissolved in 300 parts by weight of deionized water, mixed in an aqueous solution, and then After processing for a minute to form a mini emulsion, it was slowly stirred in a batch reactor, and polymerized by heating for 5 hours at a reaction temperature of 60 to 90 ℃.

1.0 g of hydrochloric acid (1M) was added to 20 g of the photochromic dye-polymer integrated microparticles solution stabilized with the silica, and stirred, while 1 g of tetraethoxysilane was added for 12 hours to encapsulate it with a mineral having a dense structure. Poly (methylmethacrylate-co-4-vinylimidazole) particles wrapped with silica as photochromic dye-polymer integrated microparticles were prepared.

Comparative Example 1

100 parts by weight of styrene, 10 parts by weight of 4-vinylpyridine, 0.05 parts by weight of initiator V65, 4.0 parts by weight of hexadecane, 0.1 part by weight of benzotriazole stabilizer, photochromic dye (naphthoxazine, which appears blue when exposed to ultraviolet light) 5 After mixing the parts by weight, 10 parts by weight of sodium lauryl sulfate was mixed with an aqueous solution dissolved in 300 parts by weight of deionized water, and then treated with an ultrasonic grinder for 5 minutes to form a mini emulsion, which was then slowly stirred in a batch reactor and then 60 to 90 degrees. The polymerization was carried out by heating at a reaction temperature of 5 ° C. for 5 hours to prepare photochromic dye-polymer integrated fine particles.

Comparative Example 2

100 parts by weight of styrene, 0.05 parts by weight of initiator V65, 4.0 parts by weight of hexadecane, 0.1 parts by weight of benzotriazole-based stabilizer, 5 parts by weight of methoxypropyltrimethoxysilane, photochromic dye (nap which shows blue when exposed to ultraviolet rays After mixing 5 parts by weight of sodium lauryl sulfate, 10 parts by weight of sodium lauryl sulfate was mixed in an aqueous solution dissolved in 300 parts by weight of deionized water, and then treated with an ultrasonic grinder for 5 minutes to form a mini emulsion, which was then slowly stirred in a batch reactor. The polymerization was carried out by heating at a reaction temperature of 60 to 90 ° C. for 5 hours.

The obtained photochromic dye-polymer integrated particulate latex was centrifuged at 17000 RPM for 2 hours using a Hanil centrifuge MEGA17R to disperse the precipitated portion again in water. The centrifugation-re-dispersion process was repeated three times to obtain a photochromic dye-polymer integrated particulate latex from which the emulsifier was removed.

200 g of water, 20 g of ethyl alcohol, 2.5 g of ammonia water (17%) were added to 10 g of the photochromic dye-polymer-integrated particulate latex (17% solids) from which the emulsifier was removed, and 5 g of tetraethoxysilane was stirred. Charged over time to produce photochromic dye-polymer integrated microparticles.

The microparticles prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were spin-coated at 1000 rpm for 10 seconds on a transparent substrate, and then dried in an oven at 80 ° C. to prepare a transparent photochromic film having a thickness of 3 to 5 μm. It was. Then, the film was irradiated with 365 nm ultraviolet light (1.35 mW / cm ² ) for 5 minutes, and then immediately placed in a UV-vis detector to measure output light in decolorized and colored states, respectively, and the results are shown in Table 1 below. Indicated. ΔOD was calculated according to Equation 1 below.

[Equation 1]

OD = log (T% bleached / T% activated)

division Example Comparative example One 2 3 One 2 Solid content (%) 28 29 31 29 3 Initial △ OD _max 0.41 0.46 0.44 0.48 0.40 △ OD _max after 3 months left outdoors 0.37 0.40 0.40 0 0.31 Film thickness (㎛) 3.1 3.3 3.2 3.3 3.2 λ _max (nm) 618 618 619 618 619 t _1/2 (sec) 24 24 24 24 24

As shown in Table 1, a photochromic film prepared using the photochromic dye-polymer integrated microparticles encapsulated with the inorganic particles of Examples 1 to 3 prepared using a Pickering emulsion containing silica nanoparticles according to the present invention. In the case of compared with the photochromic dye-polymer integrated microparticles encapsulated with the inorganic material of Comparative Example 1 or Comparative Example 2 prepared without using the inorganic encapsulated Pickering emulsion it was confirmed that the stability over time in the outdoor conditions is very excellent. . In addition, the production of photochromic dye-polymer-integrated microparticles encapsulated with minerals in the state of high solid content was possible, and thus it was confirmed that the productivity was greatly improved.

As described above, the photochromic dye-polymerized microparticles encapsulated with the inorganic material prepared according to the present invention have an effect of improving photochromic performance, being stable to ultraviolet rays and free radicals, and having an excellent oxygen barrier property. In addition, it is possible to produce photochromic dye-polymerized microparticles encapsulated with an inorganic material even in a high solid content, thereby improving productivity.

Although described in detail above with reference to the specific embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention, and such variations and modifications belong to the appended claims. It is also natural.

Claims (17)

a) mixing a monomer, silica nanoparticles, a comonomer having affinity with the silica nanoparticles, and a photochromic dye to prepare a Pickering mini emulsion; b) polymerizing the Pickering mini-emulsion to produce photochromic dye-polymer-integrated microparticles in which a photochromic dye is embedded in a polymer and stabilized with silica; And c) forming an inorganic layer on the surface of the photochromic dye-polymer integrated microparticles; Method for producing a photochromic dye-polymer integrated microparticles encapsulated with an inorganic, characterized in that consisting of. The method of claim 1, Pickering mini-emulsion of step a) is homogenized by mixing monomer, silica nanoparticles, comonomers, photochromic dye, hydrophobic agent, photochromic dye stabilizer, initiator and deionized water and buffer for pH adjustment as needed A process for producing an inorganic encapsulated photochromic dye-polymer integrated microparticle, which is prepared. The method of claim 2, The silica nanoparticles are dispersed in water, and the weight ratio of silica solids is 1 to 70%, characterized in that the production of inorganic encapsulated photochromic dye-polymer integrated microparticles. The method of claim 2, The silica nanoparticles have a particle size of 5 to 30 nm, characterized in that the production of inorganic encapsulated photochromic dye-polymer integrated microparticles. The method of claim 2, The comonomer is a compound capable of free radical polymerization having affinity with the silica nanoparticles, and is selected from the group consisting of 4-vinylpyridine, vinyl imidazole, and diallyl methylammonium chloride, the content of which is 100 weights of monomers. A method for producing an inorganic encapsulated photochromic dye-polymer integrated microparticles, characterized in that it is included in an amount of 0.1 to 100 parts by weight relative to the part. The method of claim 2, The photochromic dye is at least one selected from the group consisting of benzopyrans, naphthopyrans, spiropyrans, spirooxazines, pulzimids, diarylethenes and azo compound-based photochromic compounds, the content of which is 100 monomers. A method for producing an inorganic encapsulated photochromic dye-polymer integrated microparticles, characterized in that it is contained in an amount of 0.1 to 20 parts by weight relative to parts by weight. The method of claim 2, The hydrophobic agent (强 疏 水劑, ultrahydrophobe) is a compound that is soluble in water at 25 ° C. below 5 × 10 ⁻⁶ g / kg, and its content is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the monomer. A method for producing photochromic dye-polymer integrated microparticles encapsulated with an inorganic substance. The method of claim 2, The initiator is at least one selected from the group consisting of a peroxide-based compound initiator, an azo-based compound initiator and a redox-based initiator, encapsulated in minerals, characterized in that the content is contained in 0.01 to 0.3 parts by weight based on 100 parts by weight of the monomer. A method for producing a photochromic dye-polymer integrated microparticles. The method of claim 2, The photochromic dye stabilizer is selected from the group consisting of benzophenone-based, benzotriazole-based, and hindered amine-based inorganic minerals, characterized in that the content is contained in 0.1 to 20 parts by weight based on 100 parts by weight of the monomer. Method for producing encapsulated photochromic dye-polymer integrated microparticles. The method of claim 2, The deionized water is 100 to 800 parts by weight based on 100 parts by weight of monomers, characterized in that the production of inorganic encapsulated photochromic dye-polymer integrated microparticles. The method of claim 2, The pH control buffer is a method for producing an inorganic encapsulated photochromic dye-polymer integrated microparticles, characterized in that it comprises 0.01 to 5 parts by weight with respect to 100 parts by weight of the monomer. The method of claim 1, The inorganic layer of step c) reacts with photochromic dye-polymer integrated particles, alkoxy metal and ammonium base or hydrochloric acid and deionized water, if necessary, at room temperature, reacted with silica nanoparticles prepared in step b). A process for producing an inorganic encapsulated photochromic dye-polymer integrated microparticle, which is prepared. The method of claim 12, The alkoxy metal is at least one selected from the group consisting of Ti, Zr Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W and In, the content of which is wrapped with silica nanoparticles of step b) A method for producing inorganic encapsulated photochromic dye-polymer-integrated microparticles, comprising 0.1 to 300 parts by weight with respect to 100 parts by weight of deep photochromic dye-polymer integrated particles. The method of claim 12, The alkoxy metal is a method of producing an inorganic encapsulated photochromic dye-polymer integrated microparticles, characterized in that the continuous injection, temporary injection or partial injection. The method of claim 1, And c) hydrothermally reacting at 80 to 200 ° C. for 3 to 200 hours after step c). It is prepared by the manufacturing method of any one of claims 1 to 15 a) a polymer core layer in which a photochromic dye is dispersed and b) an inorganic layer surrounding the surface of the polymer core layer Photochromic dye-polymer integrated microparticles | fine-particles encapsulated with the mineral characterized by including the. The method of claim 16, An inorganic encapsulated photochromic dye-polymer-integrated microparticles, characterized in that the inorganic layer has a thickness of 20 to 100 nm.

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