KR20060125267A - Coating composition for thermoset type film and film prepared therefrom - Google Patents

Abstract

Provided are a coating composition for forming a thermosetting film which is excellent in transparency and is remarkably low in refractive index, a method for preparing thermosetting film by using the composition, and a thermosetting film prepared by the method. The coating composition comprises 60 wt% or more of a porous organic/inorganic hybrid nanoparticle; an organosiloxane-based thermosetting compound; and a solvent. Preferably the porous organic/inorganic hybrid nanoparticle has an average diameter of 5-30 nm and a C/Si maximum ratio of 0.65. The porous organic/inorganic hybrid nanoparticle is prepared by reacting a silane compound, a structure control agent, water and a solvent by hydrolysis and condensation to prepare a porous nanoparticle having an average diameter of 5-30 nm; and removing the structure control agent.

Description

Coating composition for thermosetting film formation and film prepared therefrom {COATING COMPOSITION FOR THERMOSET TYPE FILM AND FILM PREPARED THEREFROM}

1 is a graph showing the change in refractive index according to the nanoparticle content.

The present invention relates to a coating composition for forming a thermosetting film and a film prepared therefrom, and more particularly, to a porous silane compound having a particle size of a specific size for application to a low refractive film by using a structural control agent. After the formation, the structure control agent used for forming the pore was removed by a simple method prior to film formation, thereby making it possible to manufacture an ultra low refractive index film having a significantly low refractive index at a temperature lower than 120 ° C. The present invention relates to a coating composition for forming a thermosetting film suitable for use as a low refractive film or a low reflection film for use and a film prepared therefrom.

Generally, when observing visual information such as an object or a character through a transparent substrate or observing an image from a reflective layer through a transparent substrate of a mirror, the transparent substrate is reflected by an external appearance, making it difficult to see visual information inside. there was.

In particular, with the development of display technology in recent years, the interest in the anti-reflection function is increasing as the screen size is increased and the screen is required to be clearer. When the anti-reflection function is applied to the transparent substrate, the glare caused by external light is prevented. As a result, a clearer image can be obtained.

Conventional techniques for preventing reflection of the surface of a transparent substrate include a method of forming a transparent metal oxide layer on a transparent substrate by chemical or physical vapor deposition. The method is excellent in antireflection effect by reducing the reflection of light in a large area, but the deposition process shows insufficient productivity for mass production, and its use is gradually decreasing recently.

In addition, a method for producing an antireflection film using a coating liquid containing inorganic fine particles such as silica or inorganic fine particles, an antireflection film using a composition containing a fluorine-based low refractive organic material, a fluorine-based organic compound, a fluorine-based silane compound, etc. There is a way. However, the prior arts using the coating liquid or the fluorine resin containing the inorganic fine particles do not present a method for forming an ultra low refractive film having a refractive index of 1.4 or more and 1.36 or less. In particular, in the case of fluorine-based resins, there is an advantage that the refractive index may be lowered as the fluorine content is increased. There is a limit to lowering.

On the other hand, as a method of forming a low refractive or low reflection film, there is a method for producing a film using a siloxane-based thermosetting resin and a method for producing a film using a photocurable resin such as an acrylic resin, and in terms of film strength and low refractive index The silicon-based thermosetting process is more preferable than the photocuring process.

Recently, according to the needs of low dielectric materials in the semiconductor field, there are various methods of preparing an insulating film by introducing organic porogen or using a sol-gel process without using porogen. In order to improve dielectric properties, there is a problem in that a high temperature manufacturing process is used, and most compositions are not suitable for use in low refractive and anti-reflection films for displays.

Meanwhile, a porous particle was prepared by hydrolyzing and condensing silica using a structure controlling agent as a conventional method for preparing porous particles, and then treating the same at a high temperature of 400 to 500 ° C. or higher to remove the structure controlling agent. However, the prior art as described above had to be treated at a high temperature of 400 to 500 ° C. or higher, and the particles prepared after the heat treatment are also difficult to redistribute for producing the low refractive coating layer and have a large particle size, thereby preventing the obtaining of a transparent low refractive film. In addition, when the treatment is not performed at a high temperature of 400 to 500 ° C. or higher, there is a problem in that the refractive index is high when applied to a low refractive film which must be manufactured by a low temperature process such as a plastic substrate because the structural control agent is contained in the inorganic fine particles.

Therefore, it is possible to manufacture a low refractive film that can be manufactured by a low temperature process by applying to a low refractive film, has a short curing time, and has low reflection properties and excellent thermosetting low reflection film. to be.

In order to solve the problems of the prior art as described above, the present invention after forming a porous (porous) by using a structural control agent in a silane compound having a particle size of a specific size in order to apply to a low refractive film, By removing the structural control agent used for a simple method prior to film formation, it is possible to produce a very low refractive index film having a very low refractive index at a temperature lower than 120 ° C, and to a low refractive film or a low reflection film for various uses including a display. It is an object to provide a coating composition for forming a thermosetting film suitable for use and a film prepared therefrom.

It is another object of the present invention to provide a coating composition for forming a thermosetting film and a film prepared therefrom, which is very simple in thermal curing, excellent in transparency, and excellent in basic properties to a low refractive film.

In order to achieve the above object, the present invention provides a coating composition for forming a thermosetting film,

a) porous organic / inorganic hybrid nanoparticles;

b) organosiloxane-based thermosetting compounds; And

c) solvent

It provides a coating composition for forming a thermosetting film comprising a.

In another aspect, the present invention provides a method for producing a thermosetting film, characterized in that the coating composition for forming a thermosetting film formed on the substrate and then cured.

The present invention also provides a thermosetting membrane prepared by the above method.

Hereinafter, the present invention will be described in detail.

The present inventors formed a porous layer of a silane compound having a particle size of a specific size for application to a low refractive film by using a structural control agent, and then a simple method before forming the film using the structural control agent used for forming the pore. As a result of applying the porous organic / inorganic hybrid nanoparticles prepared by removal to the thermosetting membrane-forming coating composition, it is possible not only to manufacture an ultra low refractive index film having a very low refractive index at a temperature lower than 120 ° C. Not only is it suitable for use as a low-refractive film or a low-reflective film of use, but also confirmed that the manufacturing process is very simple and excellent in film strength and transparency, to complete the present invention based on this.

The coating composition for forming a thermosetting film of the present invention is characterized in that it comprises a porous organic / inorganic hybrid nanoparticles, an organosiloxane-based thermosetting compound, and a solvent.

The porous organic / inorganic hybrid nanoparticles of a) used in the present invention preferably have a size of 5 to 30 nm, more preferably 5 to 20 nm. If the average particle diameter is less than 5 nm, there is a problem in that it is not effective to lower the refractive index by using the final porous organic / inorganic hybrid nanoparticles, and when the average particle diameter exceeds 30 nm, the final porous organic / inorganic hybrid nanoparticles or colloid dispersed therein The stability of the, the aggregation is easy to occur, the transparency of the particles are poor, there is a problem that the gel can be easily generated during the production of the particles.

Preferably, the porous organic / inorganic hybrid nanoparticles have a refractive index of 1.37, and more preferably, a maximum of 1.35, when the membrane is prepared after low temperature drying. When the refractive index exceeds 1.37, there is a problem in that the refractive index is limited by using porous particles in the membrane composition.

In addition, it is preferable that the porous organic / inorganic hybrid nanoparticles have a specific composition, and in particular, the porous organic / inorganic hybrid nanoparticles have a C / Si of up to 0.65 in terms of production of porous nanoparticles, stability of particles, and membrane strength. desirable. When the C / Si of the porous organic / inorganic hybrid nanoparticles is low, the dielectric constant rapidly increases due to the increase of the unreacted groups in the particles, and thus is not suitable as a low dielectric material. It is preferable that C / Si has a value below a certain value because it does not increase significantly and increases the strength of the particles.

The porous organic / inorganic hybrid nanoparticles of a) are hydrolyzed and condensed with (i) a silane compound, ii) a structural control agent, iii) water, and iii) a solvent, and have a pore having an average particle diameter of 5 to 30 nm. After forming into nanoparticles, the average particle diameter is prepared by removing the structural control agent from the porous nanoparticles having a diameter of 5 to 30 nm.

The silane compound of i) used for the production of the nanoparticles may be any silane compound composed of silicon, oxygen, carbon, and hydrogen, and in particular, a silane compound represented by the following Chemical Formula 1 or Chemical Formula 2 is preferably used. .

[Formula 1]

[Formula 2]

In Formula 1 or Formula 2,

R ¹ is a non-hydrolyzable functional group which is hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, preferably unsubstituted or substituted with fluorine. Linear or branched alkyl of 1 to 4 carbon atoms,

R ² and R ³ are each independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms.

The silane compound may be used alone or in a mixture of two components. It is preferable that the C / Si of the silane compound represented by the formula (2) is at most 0.65, more preferably 1 mole of the silane compound represented by the formula (1). It is preferable that C / Si is 0.5 or less. When the C / Si exceeds 0.65, there is a problem that it is difficult to manufacture stable particles of the final nanoparticles and the mechanical properties may be degraded.

As a structural control agent of ii) used in the preparation of the nanoparticles, it is possible to use a conventional structural control agent for controlling particle growth, and specifically, it is preferable to use a quaternary ammonium salt, more preferably tetra Alkyl ammonium hydroxides, such as methyl ammonium hydroxide, tetra ethyl ammonium hydroxide, tetra propyl ammonium hydroxide, or tetra butyl ammonium hydroxide, are used.

The alkyl ammonium hydroxide is a structural control agent and at the same time, it is not necessary to add a separate base catalyst in the preparation of the porous organic / inorganic hybrid nanoparticles of the present invention as a base catalyst, but if necessary to adjust the pH by adding a base catalyst By doing so, hydrolysis and condensation reactions can be carried out. At this time, usable base catalysts include ammonia water, organic amines and the like.

The structural control agent may be used by adjusting the amount of the structural control agent according to the type, reaction conditions, etc. of the structural control agent, in particular, it is preferably used in 0.05 to 0.25 moles, more preferably 0.06 to 0.15 moles per 1 mole of the silane compound. Will be. If the amount is less than 0.05, there is a problem that the gel may occur, if the amount exceeds 0.25 mole there is a problem that it is difficult to form a low refractive index film of less than 1.37 by using the grain growth is suppressed.

I) water used in the preparation of the nanoparticles is used for hydrolysis of the silane compound.

The water is preferably used in 0.5 to 10 moles, more preferably 1 to 5 moles per 1 mole of the hydrolyzable functional group of the silane compound. If the amount is less than 0.5 moles, sufficient hydrolysis and condensation reactions do not occur, and there is a problem that the low refractive properties and mechanical properties of the membrane may be lowered. If the amount exceeds 10 moles, gelation may occur during the hydrolysis and condensation reactions. It may be, the uniformity of the components in the reaction solution is lowered, there is a problem that is not preferable in terms of mass productivity.

The solvent of i) used in the preparation of the nanoparticles is not particularly limited as long as it does not interfere with the hydrolysis and condensation reactions. Specifically, an aliphatic hydrocarbon solvent, alcohol solvent, ether solvent, ester solvent , Or an amide solvent or the like can be used, and it is particularly preferable to use an alcohol solvent.

The solvent is preferably used in an amount of 0.5 to 20 moles with respect to 1 mole of the hydrolyzable functional group of the silane compound. When the amount is less than 0.5 moles, the reaction rate may increase and there is a risk of gelation. There is a problem that the rate is reduced, the particles may not have sufficient porosity after the reaction.

The silane compound and the structural control agent as described above are hydrolyzed and condensed under water and a solvent to form porous organic / inorganic hybrid nanoparticles.

Although the reaction conditions of the hydrolysis and condensation reaction is not particularly limited, it is particularly preferable to react for 1 to 40 hours with stirring at a temperature of 30 to 100 ℃. The reaction temperature may be maintained at a constant temperature during the reaction, or may be reacted while controlling the temperature intermittently or continuously.

As described above, the hydrolysis and condensation reaction may be carried out at normal pressure, and more preferably, when the reaction is carried out by pressing at a predetermined pressure or more, it is possible to produce porous particles having a lower refractive index. In general, it is preferable to seal and react the reactor at 5 to 70 ° C. or more above the boiling point of the reaction organic solvent. There is a problem that the pressure is not sufficiently applied when the temperature is reacted below 5 ℃, there is a problem in that the reaction pressure is high to stably grow the particles when the reaction at 70 ℃ or more.

When the porous organic / inorganic hybrid nanoparticles are manufactured to a certain size by the hydrolysis and condensation reaction as described above, and then the porous organic / inorganic hybrid nanoparticles are dried at low temperature to remove water and solvents and to produce a membrane by only the particles themselves The particles are grown so that the refractive index is at most 1.37, preferably at most 1.35. After growing the porous organic / inorganic hybrid nanoparticles, the structural control agent used for growing the porous particles is removed to prepare a final porous organic / inorganic hybrid nanoparticle.

As the method for removing the structural control agent, it can be removed using a conventional method such as an ion exchange resin method, an ultrafiltration method, or washing with water.

In order to effectively lower the refractive index by using the porous nanoparticles of a) can be prepared as described above it is preferable to use a specific content or more. For example, the porous hybrid nanoparticles do not decrease linearly with the content in the film-forming composition, and the refractive index rapidly decreases above a certain amount.

In addition, the porous organic / inorganic hybrid nanoparticles may be replaced with a secondary solvent after removing specific solvents, water, and alcohols, or after solvent replacement, or by-products, if necessary, to replace the final porous organic / inorganic hybrid nanoparticles. It can manufacture.

The porous organic / inorganic hybrid nanoparticles prepared as described above are used in the coating composition without containing a structural control agent, wherein the porous organic / inorganic hybrid nanoparticles may be contained in the coating composition in the form of particles. It may be contained in the colloidal state dispersed in a solvent as needed. When such a coating composition is applied to a low refractive film, it is possible to apply to an ultra low refractive film manufactured at a low temperature of 120 ° C. or less.

The porous organic / inorganic hybrid nanoparticles of a), which can be prepared as described above, do not decrease linearly according to the content in the film-forming composition, and because the refractive index drops sharply above a certain amount, it is used in a specific amount with respect to the solid content of the coating composition. It is preferable to be.

Specifically, the content of the porous nanoparticles is preferably to use 60% by weight or more based on the solid content of the film-forming composition, more preferably to use 70% by weight or more, in this case the refractive index is sharply lowered to 1.37 or less Preferably, the ultra-low refractive film of 1.35 or less is possible.

The organosiloxane-based thermosetting compound of b) used in the present invention is not particularly limited as long as it has good adhesion to the substrate, excellent light resistance and moisture resistance, and good adhesion even when adhering with another layer. In particular, it is preferable to use an organosiloxane-based thermosetting compound in order to obtain a high film strength in the case of a low refractive film for display low reflection film is applied to a plastic substrate or film, and the film is cured in a short time at a low process temperature.

The organosiloxane-based thermosetting compound may be prepared by hydrolysis and condensation reaction of an organo silane compound alone or in mixture of two or more thereof under an acid or base catalyst. In particular, in the case of the low reflection use for display, it is more preferable to mix one or more types of the fluorosilane compounds, and to perform hydrolysis and condensation reaction for improvement of low refractive index, pollution resistance, etc.

Examples of the organo silane compound include tetraalkoxy silanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, or tetra-n-butoxysilane; Methyltrimethoxysilane, Methyltriethoxysilane, Methyltriphenoxysilane, Ethyltrimethoxysilane, Ethyltriethoxysilane, Ethyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxy Trialkoxysilanes such as silane, n-propyltriphenoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, or i-propyltriphenoxysilane; Dialkoxysilanes such as dimethyldimethoxysilane or dimethylethoxysilane; Glycidoxyalkylalkoxysilanes such as 3-glycidoxypropyltrimethoxysilane or 3-glycidoxypropyltriethoxysilane; Epoxyalkylalkoxy such as 5,6-epoxyhexyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, or 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane Silanes; Isocyanate alkylalkoxysilanes such as 3-isocyanatepropyltrimethoxysilane or 3-isocyanatepropyltriethoxysilane; Or fluoroalkylsilanes such as trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, or tridecafluorotetrahydrooctyltriethoxysilane.

In addition, the organosiloxane-based thermosetting compound may be a copolymer of fluorosilane and general silane.

The coating composition for forming a film of the present invention comprising the above components includes the solvent of c), and the solvent may uniformly disperse the porous organic / inorganic hybrid nanoparticles and is not particularly limited as long as the solvent has excellent coating properties. .

The solvent may be used by mixing two or more of the same as the solvent used in the preparation of the porous organic / inorganic hybrid nanoparticles of a), may be used by replacing other solvents with a poly solvent, and may be used by mixing two or more kinds Can be. In particular, the solvent may be an aliphatic hydrocarbon solvent, an alcohol solvent, an ether solvent, an ester solvent, an amide solvent, or the like, which may be used alone or in combination of two or more thereof.

Coating composition for film formation of the present invention containing the above components may further comprise an additive as necessary.

The type and amount of the additive is not particularly limited in a range that does not impair the film properties, specifically, may be used conductive inorganic particles, salts, conductive polymers and the like to improve the antistatic properties.

In another aspect, the present invention provides a method of manufacturing a thermosetting film prepared by applying a coating composition for forming a thermosetting film comprising the above components to a substrate and then curing, wherein the film has a refractive index of 1.37. Hereinafter, it can be manufactured with a low refractive film or a low reflection film of preferably 1.35 or less.

The substrate may be a conventional transparent substrate, and specifically, a plastic sheet such as glass, polycarbonate, acrylic resin, PET, or TAC, a plastic film, or a plastic lens ), Or a plastic panel can be used.

The method of applying the coating composition for thermosetting film formation of the present invention to the substrate as described above is not particularly limited, and may vary depending on the characteristics and the coating amount of the coating liquid, for example, roll coating, gravure coating, dip The coating, bar coating, spray coating, spin coating, or extrusion coating can be carried out by conventional methods.

The thermosetting film of the present invention prepared as described above may be used to form another film above and below the film in order to impart functionality, examples thereof include: an adhesive layer for imparting adhesion; Primer layer; Or a layer for imparting antistatic, abrasion resistance, fouling resistance, and the like; And the like, and functional additives may be added as necessary to impart functionality.

The thermosetting film of the present invention as described above may be various displays such as word processors, computers, televisions, or plasma display panels; A surface of the polarizing plate used in the liquid crystal display device; Optical lenses such as sunglasses lenses made of transparent plastics, eyeglass lenses with frequency, or finder lenses for cameras; A low reflection film on the surface of a cover of various instruments or a glass of an automobile or a train; Brightness enhancement film; Or an optical waveguide film.

The coating composition for forming a thermosetting film of the present invention as described above has a very simple manufacturing process by thermosetting, excellent transparency, low refractive index compared to the general thermosetting resin, low refractive index film of various uses including a display and Can be used as a low reflection film.

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

34 g of methyltrimethoxysilane (MTMS), 52 g of tetraethoxysilane (TEOS), and 161 g of ethanol (EtOH) were mixed and stirred at room temperature. 102 g of 10 wt% aqueous tetrapropyl ammonium hydroxide (TPAOH) diluted with 66 g of distilled water was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 80 ° C., and the transparent silicate was reacted at this temperature for 20 hours. The solution was prepared. The silicate solution was cooled to room temperature, cooled to 0 ° C. in an ice-bath, and 6.4 g of 65% by weight aqueous nitric acid solution (HNO ₃ ) was added thereto, followed by stirring for 30 minutes. The resulting solution was diluted with an ether solvent.

The diluted solution was washed with distilled water to remove the structural control agent, and solvent-substituted with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator (15% by weight) of porous organic / inorganic hybrid nanoparticles. 212 g of colloid with dispersed particles were prepared. In this case, the refractive index of the film dried using only the nanoparticles was 1.269.

Then, 45 g of methyltriethoxysilane, 52 g of tetraethoxysilane, and 147 g of propylene glycol methyl ether acetate were mixed and then stirred at room temperature. 160 g of distilled water in which 485 mg of 65% by weight of nitric acid solution was dissolved was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 60 ° C., and a transparent organosiloxane solution was prepared while reacting at this temperature for 20 hours. The organosiloxane solution was cooled to room temperature, and then solvent-substituted with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator to prepare 150 g of an organic siloxane coating solution of 20% by weight.

5 g of the colloid in which the porous organic / inorganic hybrid nanoparticles prepared above were dispersed and 1.25 g of the organic siloxane coating solution were mixed to prepare a coating solution for forming the final low refractive index film.

Example 2

In Example 1, using 27 g of methyltrimethoxysilane, 63 g of tetraethoxysilane, and 102 g of a 10% by weight tetrapropyl ammonium hydroxide aqueous solution diluted with 70.5 g of distilled water, and reacted at 60 ° C, Except that 5.1 g of 65% by weight aqueous nitric acid solution was used, 209 g of a colloid in which porous organic / inorganic hybrid nanoparticles were dispersed was prepared in the same manner as in Example 1. In this case, the refractive index of the film dried using only the nanoparticles was 1.288.

Next, 26 g of tridecafluoro-1,1,2,2-tetrahydro-octyl) triethoxysilane, 9 g of methyltrimethoxysilane, 42 g of tetraethoxysilane, And 97 g of ethanol were mixed and stirred at room temperature. An aqueous solution of 0.3 g of 65 wt% aqueous nitric acid solution diluted with 99 g of distilled water was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 60 ° C., and a transparent organosiloxane solution was prepared while reacting at this temperature for 20 hours. The organosiloxane solution was solvent-substituted with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator to prepare 233 g of 15 wt% of the organic siloxane coating solution.

4 g of the colloidal organic / inorganic hybrid nanoparticles prepared above and 2.67 g of an organic siloxane coating solution were mixed to prepare a coating solution for forming a final low refractive index film.

Example 3

104 g of tetraethoxysilane (TEOS) and 184 g of ethanol (EtOH) were mixed and stirred at room temperature. 61 g of 25% by weight aqueous tetrapropyl ammonium hydroxide solution (TPAOH) diluted with 98 g of distilled water was added to the mixture, and the mixture was sufficiently mixed. Then, the temperature was raised to 80 ° C. and the reaction was carried out at this temperature for 30 hours. Was prepared. After the silicate solution was cooled to room temperature, the temperature was lowered by an ice bath at 0 ° C., and 9.5 g of 65% by weight aqueous nitric acid solution (HNO ₃ ) was added thereto, followed by stirring for 30 minutes, and the resulting solution was diluted with water and an ethanol solvent.

The diluted solution was removed using a ultrafiltration membrane and solvent-substituted with ethanol to prepare 200 g of a colloid in which 15 wt% of porous organic / inorganic hybrid nanoparticles were dispersed. In this case, the refractive index of the film dried using only the nanoparticles was 1.295.

Next, 26 g of tridecafluoro-1,1,2,2-tetrahydro-octyl) triethoxysilane, 9 g of methyltrimethoxysilane, 42 g of tetraethoxysilane, And 97 g of ethanol were mixed and stirred at room temperature. An aqueous solution of 0.3 g of 65 wt% aqueous nitric acid solution diluted with 99 g of distilled water was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 60 ° C., and a transparent organosiloxane solution was prepared while reacting at this temperature for 20 hours. The organosiloxane solution was solvent-substituted with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator to prepare 233 g of 15 wt% of the organic siloxane coating solution.

4 g of the colloidal organic / inorganic hybrid nanoparticles prepared above and 2.67 g of an organic siloxane coating solution were mixed to prepare a coating solution for forming a final low refractive index film.

Comparative Example 1

45 g of methyltriethoxysilane, 52 g of tetraethoxysilane, and 147 g of propylene glycol methyl ether acetate were mixed and then stirred at room temperature. 160 g of distilled water solution in which 485 mg of 65% by weight of nitric acid solution was dissolved was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 60 ° C., and a transparent organosiloxane solution was prepared while reacting at this temperature for 20 hours. The organosiloxane solution was cooled to room temperature, and then solvent-substituted with propylene glycol methyl ether acetate using a rotary evaporator to prepare 159 g of a 20 wt% organosiloxane coating solution.

Comparative Example 2

34 g of methyltrimethoxysilane, 52 g of tetraethoxysilane, and 161 g of ethanol were mixed, followed by stirring at room temperature. 102 g of 10 wt% tetrapropyl ammonium hydroxide aqueous solution diluted with 66 g of distilled water was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 80 ° C., and a transparent silicate solution was prepared while reacting at this temperature for 20 hours. It was. The silicate solution was cooled to room temperature, cooled to 0 ° C. ice-bath, and 4.5 g of 65% by weight aqueous nitric acid solution (HNO ₃ ) was added thereto, followed by stirring for 30 minutes. The resulting solution was diluted with an ether solvent. After diluting the diluted solution with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator, 212 g of a silicate coating solution was prepared.

Comparative Example 3

3 g of the organic siloxane coating liquid prepared in Comparative Example 1 and 2.7 g of the silicate coating liquid prepared in Comparative Example 2 were mixed to prepare a final coating composition.

Comparative Example 4

26 g tridecafluoro-1,1,2,2-tetrahydro-octyl) triethoxysilane, 9 g methyltriethoxysilane, 42 g tetraethoxysilane, and ethanol 97 g was mixed and stirred at room temperature. 0.3 g of 65% by weight aqueous nitric acid solution (HNO ₃ ) diluted with 99 g of distilled water was added to the mixed solution, and the mixture was sufficiently mixed. Then, the temperature was raised to 60 ° C. and a reaction was performed at this temperature for 20 hours to prepare a transparent silicate solution. The silicate solution was solvent-substituted with propylene glycol methyl ether acetate (PGMEA) using a rotary evaporator, and then 233 g of 15 wt% of the organic siloxane coating solution was prepared.

Comparative Example 5

3 g of the colloid in which the porous organic / inorganic hybrid nanoparticles prepared in Example 1 were dispersed and 2.0 g of a propylene glycol methyl ether acetate solution in which 15 wt% of dipentaerythritolhexaacrylate (DPHA) was dissolved were mixed. Thereafter, 60 mg of 2,2-dimethoxy-2-phenyl-acetophenone was added to prepare a coating solution for forming a low refractive film.

Using the coating compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 5 as described above, the refractive index, film strength, and minimum reflectance were measured as follows, and the results are shown in Table 1 below.

A) Refractive index and intensity-spin coating the coating composition prepared in Examples 1 to 3 and Comparative Examples 1 to 5 on the silicon wafer, 90 seconds at 80 ℃, 1 hour at 100 ℃ Baked for and measured using an ellipsometer and nano indenter.

B) Minimum reflectance-After coating the coating composition prepared in Examples 1 to 3 and Comparative Examples 1 to 4 using a wire bar on the TAC film, and cured at 100 ℃ for 1 hour after the antireflection film The lowest reflectance in visible light was measured using a spectroscopic reflectance meter, and more than 2% was insufficient, 1.5 to 2% was normal, 1 to 1.5% was excellent, and less than 1% was very good. On the other hand, the low reflection characteristics of the low refractive film of Comparative Example 5 is coated and baked on the substrate and then exposed to an energy of 200 mJ / ㎠, and then baked for another 30 minutes at 100 ℃ after measuring the physical properties except It was carried out under the same conditions.

division Refractive index Film strength (GPa) Reflectance Example 1 1.345 1.02 Very good Example 2 1.360 1.35 Great Example 3 1.370 1.50 Great Comparative Example 1 1.420 1.61 Inadequate Comparative Example 2 1.289 0.53 Very good Comparative Example 3 1.430 1.25 Inadequate Comparative Example 4 1.410 1.45 Inadequate Comparative Example 5 1.453 0.50 Inadequate

Through the Table 1, the refractive index of the film prepared using the film-forming coating composition of Examples 1 to 3 according to the present invention shows a significantly lower refractive index compared to Comparative Examples 1 to 5 shows excellent low reflection characteristics In addition, it was confirmed that not only the film production at low temperature, but also the strength was relatively excellent.

In addition, the refractive index according to the nanoparticle content is measured and the results are shown in FIG. 1, and as shown in FIG. 1, more preferably, when the content of the nanoparticles is 60 wt% or more with respect to the total solid content of the coating composition for forming a film. In the case of 70% by weight or more, it was confirmed that the refractive index was significantly reduced. Therefore, it was found that the content of the nanoparticles contained in a specific amount or more is very preferable in terms of lowering the refractive index.

The coating composition for forming a thermosetting low refractive index film or a low reflection film according to the present invention is a very simple process by heat curing, excellent in transparency, it is possible to manufacture an ultra low refractive index film with a significantly lower refractive index than a general thermosetting resin display It can be used as a low-reflection film of various uses, including.

Although only described in detail with respect to the described embodiments of the present invention, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical spirit of the present invention, it is natural that such variations and modifications belong to the appended claims. .

Claims (17)

In the coating composition for thermosetting film formation, a) porous organic / inorganic hybrid nanoparticles; b) organosiloxane-based thermosetting compounds; And c) solvent Coating composition for thermosetting film formation comprising a. The method of claim 1, Coating composition for thermosetting film formation, characterized in that the average particle diameter of the porous organic / inorganic hybrid nanoparticles of a) is 5 to 30 nm, C / Si is up to 0.65. The method of claim 1, The coating composition of claim 1, wherein the porous organic / inorganic hybrid nanoparticles of a) are contained in at least 60% by weight based on the total solids of the coating composition for film formation. The method of claim 1, The porous organic / inorganic hybrid nanoparticles of a) are hydrolyzed and condensed with (i) a silane compound, ii) a structural control agent, iii) water, and iii) a solvent, and have a mean particle size of 5 to 30 nm. After the formation, the coating composition for forming a thermosetting film, characterized in that prepared by removing the structural control agent from the porous nanoparticles having an average particle diameter of 5 to 30 nm. The method of claim 4, wherein A coating composition for forming a thermosetting film, characterized in that the silane compound of (iii) is a silane compound represented by the following Chemical Formula 1 or Chemical Formula 2: [Formula 1]

[Formula 2]

In Formula 1 or Formula 2, R ¹ is a non-hydrolyzable functional group which is hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, R ² and R ³ are each independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms. The method of claim 4, wherein The structural control agent is at least one selected from alkyl ammonium hydroxides consisting of tetra methyl ammonium hydroxide, tetra ethyl ammonium hydroxide, tetra propyl alkyl ammonium hydroxide, and tetra butyl ammonium hydroxide. Coating composition for thermosetting film formation. The method of claim 4, wherein A coating composition for forming a thermosetting film, wherein the structural control agent is used in an amount of 0.05 to 0.25 mol based on 1 mol of the silane compound. The method of claim 4, wherein The coating composition for forming a thermosetting film, characterized in that the structural control agent is removed by ion exchange resin method, ultrafiltration, or washing with water. The method of claim 1, The coating composition for forming a thermosetting film, wherein the organosiloxane-based thermosetting compound of b) is prepared by hydrolysis and condensation of an organosilane compound under an acid or base catalyst. The method of claim 9, The organo silane compound is tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, methyltrimethoxysilane, methyltrie Methoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltriphenoxysilane , i-propyltrimethoxysilane, i-propyltriethoxysilane, i-propyltriphenoxysilane, dimethyldimethoxysilane, dimethylethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glyci Doxypropyltriethoxysilane, 5,6-epoxyhexyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxy Silane, 3-isocyanatepropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, triple Oro trimethoxysilane, trifluoromethyl propyltriethoxysilane the silane, and tri deca-fluoro-tetrahydro-octanoic tilt Rie least one selected characteristic that a heat-curable coating composition for film formation which are from the group consisting of silane. The method of claim 1, The coating composition for forming a thermosetting film, wherein the organosiloxane-based thermosetting compound of b) is a copolymer of fluorosilane and general silane. A method for producing a thermosetting film, characterized in that the coating composition for forming a thermosetting film according to claim 1 is applied to a substrate and then cured. The method of claim 12, Wherein said curing is carried out at a temperature of up to 200 ° C. A film produced by the method according to claim 12. The method of claim 14, And the film is a low refractive film or a low reflection film. The method of claim 15, The low refractive index film has a refractive index of 1.37 or less. The method of claim 15, The film is a surface of a polarizing plate used in a word processor, a computer, a television or a plasma display panel, a liquid crystal display device, a sunglasses lens, a spectacle lens with a camera, a finder lens for a camera, a cover of an instrument, a glass of a vehicle, a glass of a tank, A film characterized by being used as a brightness enhancement film or an optical waveguide film.

Images