KR20190115813A - a film with excellent transmittance - Google Patents

Abstract

The present invention relates to a transmittance enhancing film and a method of manufacturing the same. More specifically, the present invention relates to a method of manufacturing a transmittance enhancing film comprising a step of manufacturing a high refractive index coating layer on at least one side of the film; and manufacturing a low refractive coating layer on the high refractive coating layer, and to a transmittance enhancing film manufactured therefrom. The present invention can lower the reflectance of the film and increase the transmittance, and can provide a method for manufacturing a transmittance enhancing film excellent in adhesion, durability, water resistance, and thermal stability. In addition, by forming a high refractive index coating layer and a low refractive index coating layer on the film, the present invention can provide a transmittance enhancing film which is excellent in adhesion, durability, water resistance, and thermal stability and thus can be stably used for a long time in a solar cell, a polarizing plate, a liquid crystal display, and a lens, or the like.

Description

Transmittance Enhancement Film {a film with excellent transmittance}

The present invention relates to a transmittance improving film and a method of manufacturing the same, and more particularly, to prepare a high refractive index coating layer on at least one side of the film, and to prepare a low refractive index coating layer on the high refractive coating layer. It relates to a method and a transmittance improving film produced therefrom.

Optical films started later than general polymer films used for packaging materials, household goods, automobiles, etc., but the demand is continuously increasing as the development of LCD-related technologies and research into higher functionalization of films are in progress.

The optical film includes a viewing angle expanding film, an antireflection film, a compensation film, a brightness rising film, and the like, and a polyester film is most commonly used for such an optical film.

The polyester film has stable physical properties over a wide temperature range from low temperature to high temperature, excellent chemical resistance compared to other polymer resins, and good mechanical strength, surface properties, and uniformity of thickness. Since it has excellent applicability, it is widely applied to condensers, photographic films, labels, pressure-sensitive tapes, laminates, transfer tapes, polarizing plates, ceramic sheets, and the like.

In order for the polyester film to be used as an optical film, excellent light transmittance and low reflectance should be used. Various studies have been carried out, such as using an anti-reflection film to maximize such characteristics (Korean Patent Publication No. 10-2013- 0015935, Korean Patent Publication No. 10-2013-0021182, Korean Patent Registration No. 10-1205477).

However, the technique disclosed in the above document has a high refractive index and a high reflectance of the antireflection film, a decrease in the transmittance, and poor curing properties, and thus cannot be used stably for an optical film for a long time.

Korean Patent Publication No. 10-2013-0015935 Korean Patent Publication No. 10-2013-0021182 Korea Patent Registration No. 10-1205477

The present invention is to solve the problems of the prior art, it is possible to lower the reflectance of the film and increase the transmittance, and to provide a method for producing a transmittance improving film excellent in adhesion, durability, water resistance and thermal stability. .

In addition, the present invention by forming a high refractive coating layer and a low refractive coating layer on the film excellent in adhesion, durability, water resistance, thermal stability, transmittance, etc. to improve the transmittance film that can be used stably for solar cells, polarizing plates, liquid crystal display devices, lenses, etc. for a long time It aims to provide.

The present invention to achieve the above object (a) washing the film; (b) preparing a first mixture by mixing titanium dioxide nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent; (c) preparing a second mixture by mixing silica nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent; (d) coating and curing the first mixture on at least one side of the film to produce a high refractive coating layer; And (e) coating and curing the second mixture on the high refractive coating layer to produce a low refractive coating layer.

In one embodiment of the present invention, the step (b) is a step of preparing a first stirring mixture by mixing titanium dioxide nanoparticles, diameter 3-glycidoxypropyl trimethoxysilane and acid compound of 10 ~ 200nm ; Preparing a second agitator by mixing propylene glycol methyl ether and methanol to the first agitator; Preparing a third stirring material by mixing a catalyst with the second stirring material; Preparing a fourth stirring product by mixing butylglycidyl ether in the third stirring material; And mixing methanol with the fourth agitator to prepare a fifth agitator.

In one embodiment of the present invention, the weight ratio of propylene glycol methyl ether and methanol contained in the second stirring is characterized in that 20 to 50:80 to 50.

In one embodiment of the present invention, the step (c) is a first composition by mixing silica nanoparticles, 10-glycidoxypropyltrimethoxysilane, methyltrimethoxysilane and acid compounds having a diameter of 10 ~ 200nm Preparing a; Preparing a second composition by mixing a catalyst with the first composition; Preparing a third composition by mixing butylglycidyl ether in the second composition; And mixing propylene glycol methyl ether and ethanol to the third composition to prepare a fourth composition.

In one embodiment of the present invention, the weight ratio of the 3-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane is characterized in that 40 to 60:60 to 40.

In another aspect, the present invention provides a transmittance improving film produced by the above production method.

The present invention is to solve the problems of the prior art, can lower the reflectance of the film and increase the transmittance, can provide a method for producing a transmittance improving film excellent in adhesion, durability, water resistance and thermal stability.

In addition, the present invention by forming a high refractive coating layer and a low refractive coating layer on the film excellent in adhesion, durability, water resistance, thermal stability, transmittance, etc. to improve the transmittance film that can be used stably for solar cells, polarizing plates, liquid crystal display devices, lenses, etc. for a long time Can provide.

Hereinafter, the present invention will be described in detail with reference to Examples. The terms, examples, etc. used in the present invention are merely illustrated to explain the present invention in more detail and to help those skilled in the art, and the scope of the present invention is not limited thereto.

Technical terms and scientific terms used in the present invention represent the meanings that are commonly understood by those of ordinary skill in the art unless otherwise defined.

The present invention comprises the steps of (a) washing the film; (b) preparing a first mixture by mixing titanium dioxide nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent; (c) preparing a second mixture by mixing silica nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent; (d) coating and curing the first mixture on at least one side of the film to produce a high refractive coating layer; And (e) coating and curing the second mixture on the high refractive coating layer to produce a low refractive coating layer.

The step (a) is to remove dust, oil, organic compounds, contaminants, etc. remaining in the film, it can be washed with demineralized water, alcohol, acidic or basic cleaning solution.

The film may be used without limitation a film, sheet or substrate such as polyester, such as polyethylene terephthalate, polyethylene naphthalate, polyamide, polycarbonate, polymethyl methacrylate, polystyrene.

In the step (b), the first mixture may be prepared by mixing titanium dioxide nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent.

The step (b) comprises the steps of preparing a first agitator by mixing titanium dioxide nanoparticles, 3-glycidoxypropyltrimethoxysilane and an acid compound having a diameter of 10 ~ 200nm; Preparing a second agitator by mixing propylene glycol methyl ether and methanol to the first agitator; Preparing a third stirring material by mixing a catalyst with the second stirring material; Preparing a fourth stirring product by mixing butylglycidyl ether in the third stirring material; And mixing methanol with the fourth stirring material to prepare a fifth stirring material.

In the present invention, the first stirring material may be prepared by mixing titanium dioxide nanoparticles having a diameter of 10 nm to 200 nm, a silane compound, and an acid compound.

Through this step, the alkoxy group of the silane compound is hydrolyzed to form a hydroxyl group. The hydroxyl group may be bonded to the surface of the titanium dioxide nanoparticles may be bonded to the silane compound on the surface of the nanoparticles.

The titanium dioxide nanoparticles have a diameter of 10 to 200 nm, preferably 10 to 60 nm. If the diameter is less than 10nm, the moisture barrier properties are lowered, and if it exceeds 200nm, it is impossible to form a uniform coating layer, so durability and weather resistance are lowered.

The silane compound has an organic functional group capable of binding to an organic compound and a hydrolyzable group capable of reacting with an inorganic substance, and the silane compound binds to the surface of titanium dioxide nanoparticles to provide properties such as water resistance, water barrier property, durability, and weather resistance. Indicates.

The content of the silane compound is preferably 20 to 50 parts by weight with respect to 100 parts by weight of nanoparticles, and when the content is less than 20 parts by weight, it is difficult to expect the improvement of adhesion. Properties, transmittance and durability deteriorate.

As the silane compound, an alkyl group-containing silane, an amino group-containing silane, an epoxy group-containing silane, an acrylate group-containing silane, an isocyanate group-containing silane, a fluorine group-containing silane, a vinyl group-containing silane, and the like can be used without limitation.

Examples of the alkyl group-containing silane include methyltrimethoxysilane, dimethyldimethoxysilane and octyltriethoxysilane.

Examples of the epoxy group-containing silanes include 2-glycidoxyethylmethyldimethoxysilane, 2-glycidoxyethylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2 -Glycidoxy ethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4- Epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, 3- (3,4-epoxycyclohexyl) propylmethyldimethoxysilane, 3- (3,4 -Epoxycyclohexyl) propylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (3, 4-epoxycyclohexyl) propyltrimethoxysilane, 3- (3,4-epoxycyclohexyl) propyltriethoxysilane, and the like.

As acrylate group containing silane, 3-methacryloxypropyl methyldimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl methyl diethoxysilane, 3-methacryloxypropyl triethoxysilane , 3-acryloxypropyltrimethoxysilane, methacryloxymethyltriethoxysilane, methacryloxymethyltrimethoxysilane and the like.

Examples of the fluorine group-containing silane include heptadecafluoro-1,1,2,2-tetradecyltrimethoxysilane, trifluoropropyltrimethoxysilane, tridecafluorooctyltrimethoxysilane and heptadecafluorodecyl Trimethoxysilane, heptadecafluorodecyltriisopropoxysilane, and the like.

In order to improve the water resistance, water barrier property, durability, weather resistance, transmittance and the like of the film, it is preferable to use an epoxy group-containing silane such as 3-glycidoxypropyltrimethoxysilane.

In addition, 3-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane may be used in a weight ratio of 40 to 60:60 to 40.

As the acid compound, hydrochloric acid, acetic acid, sulfuric acid, nitric acid, and the like may be used, and it is preferable to be used in the form of an aqueous solution. For example, 15% acetic acid aqueous solution can be used.

The content of the acid compound is preferably 10 to 20 parts by weight with respect to 100 parts by weight of the nanoparticles, when the content is less than 10 parts by weight, it is difficult to expect the improvement of adhesion, and when it exceeds 20 parts by weight, the transmittance and durability are lowered.

Propylene glycol methyl ether and methanol may be mixed with the first stirring material to prepare a second stirring material.

The propylene glycol methyl ether and methanol serve to adjust the viscosity of the composition and stabilize the composition.

In this case, the content of propylene glycol methyl ether is preferably 10 to 30 parts by weight based on 100 parts by weight of nanoparticles, and the content of methanol is preferably 20 to 50 parts by weight based on 100 parts by weight of nanoparticles.

In addition, the weight ratio of propylene glycol methyl ether and methanol is preferably 20 to 50:80 to 50. If the weight ratio is less than 20:80, the workability is lowered, and if the weight ratio exceeds 50:50, the transmittance and durability are lowered.

A third agitator may be prepared by mixing a catalyst with the second agitator.

As a catalyst, Organic metal salts, such as Cu, Fe, Co, Mn, Al, Ti, Zr, Ni, such as octylic acid, stearic acid, naphthenic acid, acetylacetonate; Metal alkoxides such as Ti, Sn, Bi, Zr, Al; Phenol compounds such as octylphenol and nonylphenol; Alcohols such as 1-butanol and 2-ethylhexanol; 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4- Imidazole derivatives such as methyl-imidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole can be used. For example, it is preferable to use aluminum acetylacetonate.

The content of the catalyst is preferably 1 to 5 parts by weight with respect to 100 parts by weight of nanoparticles, when the content is less than 1 part by weight, it is difficult to expect the improvement of adhesion, and when it exceeds 5 parts by weight, the transmittance and durability decrease.

By using a catalyst, the coating layer is easily formed at lower temperatures when the composition is coated on the film, and the coating layer has excellent heat resistance, thermal stability, and the like.

The fourth stirring material may be prepared by mixing the epoxy compound with the third stirring material.

The epoxy compound may be bonded to a silane compound bonded to the surface of the titanium dioxide nanoparticles or to a hydroxyl group formed on the surface of the titanium dioxide nanoparticles.

The content of the epoxy compound is preferably 1 to 10 parts by weight with respect to 100 parts by weight of nanoparticles, when the content is less than 1 part by weight it is difficult to expect improved adhesion, when the content exceeds 10 parts by weight, the transmittance and durability is reduced.

Examples of the epoxy compound include butylglycidyl ether (BGE), trimethylolpropane triglycidyl ether (TMPTGE), ethylene glycol diglycidyl ether, triglycidyl ether, N, N, N ', N'-tetra Glycidyl ethylenediamine, glycerin diglycidyl ether, and the like can be used without limitation, and butylglycidyl ether is preferably used.

In addition, butyl glycidyl ether (BGE) and trimethylol propane triglycidyl ether (TMPTGE) can be used simultaneously as an epoxy compound, wherein the weight ratio of butyl glycidyl ether and trimethylol propane triglycidyl ether is 60 to 80: It is preferable that it is 40-20.

The fifth stirring may be prepared by mixing a solvent with the fourth stirring.

The solvent controls the viscosity of the composition, ethanol, propylene glycol methyl ether (PGME), methanol, propanol, isopropanol, butanol and the like can be used without limitation, methanol is preferably used.

The content of the solvent is preferably 500 to 1,000 parts by weight with respect to 100 parts by weight of nanoparticles, and when the content is less than 500 parts by weight, the workability is lowered, and when the content is more than 1,000 parts by weight, the transmittance and durability are lowered.

In the step (c), a second mixture may be prepared by mixing silica nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent.

Step (c) comprises preparing a first composition by mixing silica nanoparticles having a diameter of 10 to 200 nm, 3-glycidoxypropyltrimethoxysilane, methyltrimethoxysilane, and an acid compound; Preparing a second composition by mixing a catalyst with the first composition; Preparing a third composition by mixing butylglycidyl ether in the second composition; And preparing a fourth composition by mixing propylene glycol methyl ether and ethanol in the third composition.

In the present invention, the first composition may be prepared by mixing silica nanoparticles, a silane compound, and an acid compound having a diameter of 10 to 200 nm.

Through this step, the alkoxy group of the silane compound is hydrolyzed to form a hydroxyl group. The hydroxyl group may be bonded to the surface of the silica nanoparticles may be bonded to the silane compound on the surface of the nanoparticles.

The diameter of a silica nanoparticle is 10-200 nm, and it is preferable that it is 10-60 nm. If the diameter is less than 10nm, the moisture barrier properties are lowered, and if it exceeds 200nm, it is impossible to form a uniform coating layer, so durability and weather resistance are lowered.

The silane compound has an organic functional group capable of binding to an organic compound and a hydrolyzable group capable of reacting with an inorganic substance, and the silane compound binds to the surface of silica nanoparticles to provide properties such as water resistance, water barrier property, durability, and weather resistance. Indicates.

The content of the silane compound is preferably 40 to 80 parts by weight based on 100 parts by weight of nanoparticles, and when the content is less than 40 parts by weight, it is difficult to expect the improvement of adhesion. Properties, transmittance and durability deteriorate.

As the silane compound, an alkyl group-containing silane, an amino group-containing silane, an epoxy group-containing silane, an acrylate group-containing silane, an isocyanate group-containing silane, a fluorine group-containing silane, a vinyl group-containing silane, and the like can be used without limitation.

Examples of the alkyl group-containing silane include methyltrimethoxysilane, dimethyldimethoxysilane and octyltriethoxysilane.

Examples of the epoxy group-containing silanes include 2-glycidoxyethylmethyldimethoxysilane, 2-glycidoxyethylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2 -Glycidoxy ethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4- Epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, 3- (3,4-epoxycyclohexyl) propylmethyldimethoxysilane, 3- (3,4 -Epoxycyclohexyl) propylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (3, 4-epoxycyclohexyl) propyltrimethoxysilane, 3- (3,4-epoxycyclohexyl) propyltriethoxysilane, and the like.

As acrylate group containing silane, 3-methacryloxypropyl methyldimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl methyl diethoxysilane, 3-methacryloxypropyl triethoxysilane , 3-acryloxypropyltrimethoxysilane, methacryloxymethyltriethoxysilane, methacryloxymethyltrimethoxysilane and the like.

Examples of the fluorine group-containing silane include heptadecafluoro-1,1,2,2-tetradecyltrimethoxysilane, trifluoropropyltrimethoxysilane, tridecafluorooctyltrimethoxysilane and heptadecafluorodecyl Trimethoxysilane, heptadecafluorodecyltriisopropoxysilane, and the like.

In order to improve the water resistance, water barrier property, durability, weather resistance, and transmittance of the film, a mixed silane compound of an alkyl group-containing silane and an epoxy group-containing silane is preferably used, and the weight ratio of the epoxy group-containing silane and the alkyl group-containing silane is 40 to 60: It is preferable that it is 60-40.

For example, 3-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane may be used in a weight ratio of 40 to 60:60 to 40.

For example, alkyl group-containing silanes (methyltrimethoxysilane, dimethyldimethoxysilane and octyltriethoxysilane) and 3-glycidoxypropyltrimethoxysilane can be used as the silane coupling agent, wherein 3-glyci Doxypropyltrimethoxysilane and alkyl group-containing silane are used in a weight ratio of 40 to 60:60 to 40, and the weight ratio of methyltrimethoxysilane, dimethyldimethoxysilane and octyltriethoxysilane is 100: 10 to 200: 10 to It is preferable that it is 200.

As the acid compound, hydrochloric acid, acetic acid, sulfuric acid, nitric acid, and the like may be used, and it is preferable to be used in the form of an aqueous solution. For example, 15% acetic acid aqueous solution can be used.

The content of the acid compound is preferably 15 to 35 parts by weight with respect to 100 parts by weight of the nanoparticles, when the content is less than 15 parts by weight, it is difficult to expect the improvement of adhesion, and when it exceeds 35 parts by weight, the transmittance and durability are reduced.

The second composition may be prepared by mixing a catalyst with the first composition.

As a catalyst, Organic metal salts, such as Cu, Fe, Co, Mn, Al, Ti, Zr, Ni, such as octylic acid, stearic acid, naphthenic acid, acetylacetonate; Metal alkoxides such as Ti, Sn, Bi, Zr, Al; Phenol compounds such as octylphenol and nonylphenol; Alcohols such as 1-butanol and 2-ethylhexanol; 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4- Imidazole derivatives such as methyl-imidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole can be used. For example, it is preferable to use aluminum acetylacetonate.

The content of the catalyst is preferably 1 to 5 parts by weight with respect to 100 parts by weight of nanoparticles, when the content is less than 1 part by weight, it is difficult to expect the improvement of adhesion, and when it exceeds 5 parts by weight, the transmittance and durability decrease.

By using a catalyst, the coating layer is easily formed at lower temperatures when the composition is coated on the film, and the coating layer has excellent heat resistance, thermal stability, and the like.

The third composition may be prepared by mixing the epoxy compound with the second composition.

The epoxy compound may be bonded to the silane compound bonded to the surface of the silica nanoparticles or to a hydroxyl group formed on the surface of the silica nanoparticles.

The content of the epoxy compound is preferably 1 to 10 parts by weight with respect to 100 parts by weight of nanoparticles, when the content is less than 1 part by weight it is difficult to expect improved adhesion, when the content exceeds 10 parts by weight, the transmittance and durability is reduced.

Examples of the epoxy compound include butylglycidyl ether (BGE), trimethylolpropane triglycidyl ether (TMPTGE), ethylene glycol diglycidyl ether, triglycidyl ether, N, N, N ', N'-tetra Glycidyl ethylenediamine, glycerin diglycidyl ether, and the like can be used without limitation, and butylglycidyl ether is preferably used.

In addition, butyl glycidyl ether (BGE) and trimethylol propane triglycidyl ether (TMPTGE) may be used simultaneously as an epoxy compound, wherein the weight ratio of butyl glycidyl ether and trimethylol propane triglycidyl ether is 60 to 80: It is preferable that it is 40-20.

The fourth composition may be prepared by mixing a solvent with the third composition.

The solvent controls the viscosity of the composition, ethanol, propylene glycol methyl ether (PGME), methanol, propanol, isopropanol, butanol and the like can be used without limitation.

The content of the solvent is preferably 500 to 1,500 parts by weight based on 100 parts by weight of nanoparticles, and when the content is less than 500 parts by weight, the workability is lowered, and when the content is more than 1,500 parts by weight, the transmittance and durability are lowered.

In this invention, it is preferable to use ethanol and propylene glycol methyl ether simultaneously as a solvent.

In this case, the content of ethanol is preferably 600 to 1,400 parts by weight based on 100 parts by weight of nanoparticles, and the content of propylene glycol methyl ether is preferably 20 to 100 parts by weight based on 100 parts by weight of nanoparticles.

In the step (d), the high refractive index coating layer may be prepared by coating and curing the first mixture on at least one side of the film.

Step (d) may use a known coating method, bar coating, meniscus coating, spray coating, roll coating, spin coating, immersion coating may be used without limitation.

In the step (d), the first mixture is coated on the film, and then cured at 60 to 150 ° C. to form a high refractive coating layer.

At this time, the high refractive index means having a refractive index of 1.7 ~ 1.9.

In the step (e), the high refractive coating layer may be coated with the second mixture and cured to produce a low refractive coating layer.

The step (e) may use a known coating method, bar coating, meniscus coating, spray coating, roll coating, spin coating, immersion coating and the like may be used without limitation.

In the step (e), after coating the second mixture on the high refractive coating layer, it may be cured at 60 to 150 ° C. to form a low refractive coating layer.

In this case, the low refractive index means having a refractive index of 1.4 ~ 1.6.

The present invention also relates to a transmittance improving film produced by the above production method.

The film of the present invention can lower the reflectance and increase the transmittance, and exhibits excellent adhesive strength, durability, water resistance and thermal stability.

In addition, the present invention by forming a high refractive index coating layer and a low refractive coating layer on the film in order to be excellent in adhesion, durability, water resistance, thermal stability, transmittance, etc. can be used stably for a long time, such as solar cells, polarizing plates, liquid crystal display devices, lenses.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. The following examples are merely illustrated for the practice of the present invention, but the content of the present invention is not limited by the following examples.

(Example 1)

The polyethylene terephthalate film was washed with a detergent to remove dirt, oils, organic compounds, contaminants, etc. present in the film.

A first stirring product was prepared by mixing 100 parts by weight of titanium dioxide nanoparticles having a diameter of 50 nm, 30 parts by weight of 3-glycidoxypropyltrimethoxysilane, and 15 parts by weight of 15% acetic acid aqueous solution.

20 parts by weight of propylene glycol methyl ether and 30 parts by weight of methanol were mixed with the first mixture to prepare a second mixture.

3 parts by weight of aluminum acetylacetonate was mixed with the second agitator to prepare a third agitator.

5 parts by weight of butylglycidyl ether was mixed with the third stirring material to prepare a fourth stirring material.

800 parts by weight of methanol was mixed with the fourth stirring material to prepare a fifth stirring material.

A first composition was prepared by mixing 100 parts by weight of silica nanoparticles having a diameter of 50 nm, 30 parts by weight of 3-glycidoxypropyltrimethoxysilane, 30 parts by weight of methyltrimethoxysilane, and 20 parts by weight of 15% acetic acid aqueous solution.

3 parts by weight of aluminum acetylacetonate was mixed with the first composition to prepare a second composition.

The third composition was prepared by mixing 5 parts by weight of butylglycidyl ether in the second composition.

40 parts by weight of propylene glycol methyl ether and 1,000 parts by weight of ethanol were mixed with the third composition to prepare a fourth composition.

The fifth agitator was coated on the polyethylene terephthalate film with a bar coating, and cured at 100 ° C. to form a high refractive coating layer.

After applying the fourth composition to the high refractive coating layer by a bar coating, it was cured at 100 ° C to form a low refractive coating layer to prepare a transmittance improving film.

(Example 2)

A film was prepared in the same manner as in Example 1, except that 10 parts by weight of propylene glycol methyl ether and 50 parts by weight of methanol were mixed with the first stirring material to prepare a second stirring material.

(Example 3)

A film was prepared in the same manner as in Example 1, except that 30 parts by weight of propylene glycol methyl ether and 20 parts by weight of methanol were mixed with the first stirring material to prepare a second stirring material.

(Example 4)

A film was prepared in the same manner as in Example 1, except that the first composition was prepared using 20 parts by weight of 3-glycidoxypropyltrimethoxysilane and 40 parts by weight of methyltrimethoxysilane.

(Example 5)

A film was prepared in the same manner as in Example 1, except that the first composition was prepared using 40 parts by weight of 3-glycidoxypropyltrimethoxysilane and 20 parts by weight of methyltrimethoxysilane.

(Example 6)

A film was prepared in the same manner as in Example 1, except that 0.5 part by weight of butylglycidyl ether was mixed with the second composition to prepare a third composition.

(Example 7)

A film was manufactured in the same manner as in Example 1, except that 15 parts by weight of butylglycidyl ether was mixed with the second composition to prepare a third composition.

(Comparative Example 1)

A film was prepared in the same manner as in Example 1, except that butylglycidyl ether was not used to prepare the fourth stirring material.

(Comparative Example 2)

A film was prepared in the same manner as in Example 1, except that butylglycidyl ether was not used in the preparation of the third composition.

(reflectivity)

The adapter MPC 2200 was mounted on the spectrophotometer UV 2450 to measure the specular reflectance at an emission angle of 5 ° at an incident angle of 5 ° in a wavelength region of 380 to 780 nm, and an average reflectance of 450 to 650 nm was calculated.

Transmittance

Total light transmittance was measured using the transmittance meter (HM-150) according to ASTM D 1003.

Reflectance and transmittance of the films prepared from the Examples and Comparative Examples were measured and the results are shown in Table 1 below.

division Example Comparative example One 2 3 4 5 6 7 One 2 reflectivity(%) 4.4 5.7 5.8 5.1 5.2 5.0 5.1 6.3 6.6 Transmittance (%) 92.6 91.6 91.2 91.1 91.2 91.5 91.0 88.5 88.9

From the results of Table 1, Examples 1 to 7 it can be seen that the reflectance of the film is low and the transmittance is increased. In particular, Example 1 is the most excellent in the said characteristic.

On the other hand, it can be seen that Comparative Examples 1 and 2 are inferior in reflectance and transmittance as compared with Examples 1 to 7.

Claims (6)

(a) washing the film;
(b) preparing a first mixture by mixing titanium dioxide nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent;
(c) preparing a second mixture by mixing silica nanoparticles having a diameter of 10 to 200 nm, a silane compound, an acid compound, a catalyst, an epoxy compound, and a solvent;
(d) coating and curing the first mixture on at least one side of the film to produce a high refractive coating layer; And
(e) coating the second mixture on the high refractive coating layer and hardening to produce a low refractive coating layer.
The method of claim 1,
Step (b)
Preparing a first stirring material by mixing titanium dioxide nanoparticles having a diameter of 10 to 200 nm, 3-glycidoxypropyltrimethoxysilane, and an acid compound;
Preparing a second agitator by mixing propylene glycol methyl ether and methanol to the first agitator;
Mixing a catalyst with the second agitator to prepare a third agitator;
Preparing a fourth stirring product by mixing butylglycidyl ether in the third stirring material; And
Mixing methanol with the fourth stirring material to produce a fifth stirring material.
The method of claim 2,
The weight ratio of propylene glycol methyl ether and methanol contained in the second stirring product is 20 to 50: 80 to 50, the method for producing a transmittance improving film, characterized in that.
The method of claim 1,
Step (c) is
Preparing a first composition by mixing silica nanoparticles having a diameter of 10 to 200 nm, 3-glycidoxypropyltrimethoxysilane, methyltrimethoxysilane, and an acid compound;
Preparing a second composition by mixing a catalyst with the first composition;
Preparing a third composition by mixing butylglycidyl ether in the second composition; And
Method for producing a transmittance improving film, comprising the step of preparing a fourth composition by mixing propylene glycol methyl ether and ethanol in the third composition.
The method of claim 4, wherein
The weight ratio of the 3-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane is 40 to 60:60 to 40, the method for producing a transmittance improving film, characterized in that.
The transmittance improvement film manufactured by the manufacturing method of any one of Claims 1-5.