WO2015152559A1 - Low refractive composition, preparation method therefor, and transparent conductive film - Google Patents

Abstract

Provided are: a low refractive composition containing an organopolysiloxane and inorganic particles having an average diameter of approximately 30-70 nm; a preparation method therefor; and a transparent conductive film.

Description

Low refractive composition, its preparation method, and transparent conductive film

A low refractive index composition, a manufacturing method thereof, and a transparent conductive film.

BACKGROUND Electronic devices such as smart phones, tablet PCs, ATMs, notebook computers, TVs, and the like having a touch screen function include a touch screen panel capable of inputting or manipulating information in response to a touch and a display device such as an LCD or an OLED.

In general, the touch screen panel may include a transparent conductive film to simultaneously implement transparency and electrical conductivity to exert a performance of responding by touch. For example, the touch screen panel includes an optical method, an ultrasonic method, a capacitive method, a resistive touch panel, and the like according to the method of position detection, and sequentially a transparent conductive film, for example, OCA (optically clear). It can be formed as a laminate of a multilayer structure including an adhesive (optically clear resin), an optical adhesive film such as OCR (Optically Clear Resin), a glass substrate or a transparent plastic substrate.

Such a transparent conductive film includes a base layer and a conductive layer including an electrode formed of a conductive material, for example, indium tin oxide (ITO), and is usually wound in a roll form or laminated with a plurality of films. Therefore, the transparent conductive films are stuck to each other, and there is a problem in that the performance of the transparent conductive film is degraded in the process of spreading the same to apply the same to the touch screen panel.

In addition, silver nanowires or the like can be used as a material for forming the electrode of the conductive layer. In the case of using such a material, the width or width of the electrode pattern can be used.

Relative to increase so as not to satisfy the index matching, the electrode pattern may be visible to the consumer using the product and the visibility may be degraded.

In one embodiment of the present invention, it provides a low refractive index composition that does not reduce the electrical conductivity while implementing excellent blocking prevention performance and excellent optical properties.

In another embodiment of the present invention, a method of preparing the low refractive index composition is provided.

In another embodiment of the present invention, including a low refractive index layer formed by the low refractive index composition, to provide a transparent conductive film that implements excellent anti-blocking performance, excellent optical properties and excellent electrical conductivity.

In one embodiment of the invention, there is provided a low refractive index composition comprising an organopolysiloxane (organopolysiloxane) and inorganic particles having an average diameter of about 30nm to about 70nm.

The inorganic particles may be included in an amount of about 0.5 parts by weight to about 20 parts by weight based on about 100 parts by weight of the organopolysiloxane.

The organopolysiloxane is an alkyl group of 1 to 18 carbon atoms, an alkoxy group of 1 to 18 carbon atoms, an ester group of 2 to 6 carbon atoms, an epoxy group of 2 to 12 carbon atoms, an alkenyl group of 2 to 12 carbon atoms, 6 carbon atoms It may include at least one functional group selected from the group consisting of 12 to 12 aromatic groups, 3 to 18 carbon atoms, acrylic group, glycidyl group, amine group, thiol group, halogen group and combinations thereof.

The organopolysiloxane may comprise a linear structure, a network structure, or both.

The organopolysiloxane may be formed by a sol-gel reaction of a composition comprising a silane compound of Formula 1 and a silane compound of Formula 2 below:

 [Formula 1]

R ¹ _x Si (OR ² ) _4-x

[Formula 2]

Si (OR ³ ) ₄

In Chemical Formula 1, R ¹ is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and having 6 to 12 carbon atoms Group, an acryl group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R ² and R ³ is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1, 2, or 3.

Before the sol-gel reaction, the inorganic particles may be further mixed and included in the composition.

The organopolysiloxane may have a weight average molecular weight of about 3,000 g / mol to about 55,000 g / mol.

The inorganic particles may include at least one particle selected from the group consisting of silica particles, alumina particles, zirconium oxide particles, titanium oxide particles, antimony oxide particles, and combinations thereof.

The low refractive index composition may not include or further include a substituted or unsubstituted monomolecular alkoxysilane compound.

In another embodiment of the present invention, it provides a transparent conductive film comprising a low refractive index layer formed by the low refractive index composition.

The low refractive layer may be formed with fine irregularities on the upper surface, the fine irregularities may be formed by the inorganic particles.

The low refractive layer may have a thickness of about 10 nm to about 50 nm.

The low refractive index layer may have a refractive index of about 1.40 to about 1.50.

The low refractive index layer may further include a high refractive index layer and a base layer sequentially, and may further include a conductive layer on top of the low refractive layer.

It may further include a hard coating layer in contact with one side or both sides of the base layer.

The transparent conductive film may have a light transmittance of about 85% or more and a haze of about 0.1% to about 0.8%.

In another embodiment of the present invention, preparing a raw material composition comprising a silane compound of Formula 1, a silane compound of Formula 2 and inorganic particles having an average diameter of about 30nm to about 70nm; And preparing a low refractive composition by performing a sol-gel reaction on the raw material composition. It provides a method for producing a low refractive index composition comprising:

[Formula 1]

R ¹ _x Si (OR ² ) _4-x

[Formula 2]

Si (OR ³ ) ₄

In Chemical Formula 1, R ¹ is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and having 6 to 12 carbon atoms Group, an acryl group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R ² and R ³ is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1, 2, or 3.

The raw material composition may be prepared by mixing the inorganic particles in an amount of about 0.5 parts by weight to about 20 parts by weight based on a total of about 100 parts by weight of the silane compound of Formula 1 and the silane compound of Formula 2.

During the sol-gel reaction, an organopolysiloxane may be formed by chemical reaction between the silane compounds.

The low refractive index composition may not reduce the electrical conductivity while implementing excellent blocking prevention performance and excellent optical properties.

1 is a schematic cross-sectional view showing two cross-sectional views of two examples, (a) and (b) of a transparent conductive film according to another embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In order to clearly describe the present invention, parts irrelevant to the description are omitted, and like reference numerals designate like elements throughout the specification.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. In the drawings, the thicknesses of layers and regions are exaggerated for clarity.

Hereinafter, any configuration is formed on the "top (or bottom)" of the substrate or "top (or bottom)" of the substrate means that any configuration is formed in contact with the top (or bottom) of the substrate. However, it is not limited to not including other configurations between the substrate and any configuration formed on (or under) the substrate.

Low refractive composition

In one embodiment of the invention, there is provided a low refractive index composition comprising an organopolysiloxane and inorganic particles having an average diameter of, for example, about 30 nm to about 70 nm. Specifically, the average diameter of the inorganic particles may be about 35nm to about 60nm.

In general, the transparent conductive film is wound in a roll form, or a plurality of films are stacked and distributed. As a result, the transparent conductive films adhere to each other and are transparent or conductive in the process of being unfolded or separated from each other for application to a touch screen panel. The performance of the film can be significantly reduced. Accordingly, in order to prevent adhesion between the transparent conductive films in the distribution process, by including the inorganic particles in the hard coating layer to form protrusions, it is possible to reduce the area of contact with each other to weaken the adhesion degree, thereby improving the performance of the transparent conductive film It exhibits anti-blocking performance that can be unfolded or peeled off without being degraded.

However, when inorganic particles are included in the hard coating composition including acrylic resin as the binder resin, the compatibility between the acrylic resin and the inorganic particles is low, and the physical properties such as specific gravity of the binder resin, surface energy, and the thickness of the hard coating layer are used. In consideration of this, in order to form protrusions on the hard coating layer, inorganic particles having a large average diameter must be included, so that the defect rate of the surface appearance during processing increases and the haze increases, thereby further deteriorating the optical properties and the electrical conductivity of the conductive layer. .

In addition, not only ITO, but also silver nanowires and the like may be used as a material for forming the electrode of the conductive layer. In the case of using such a material, the width or width of the electrode pattern is relatively increased so that the product does not satisfy the index matching property. The electrode pattern may be visually seen by the consumer to use, and thus index matching or visibility may be degraded.

Thus, in one embodiment, including inorganic particles in the low refractive index composition containing the organopolysiloxane, while improving compatibility between the components included in the low refractive index composition, the specific properties of the organopolysiloxane, such as surface energy and low refractive index Given the thickness of the layer, it is possible to reduce the average diameter of the inorganic particles required to achieve the antiblocking performance, that is, the antiblocking performance, to an appropriately small level.

Accordingly, the transparent conductive film including the low refractive index layer formed by the low refractive index composition exhibits excellent anti-blocking performance while in the coating process of the low refractive index composition, the defect rate of the surface appearance is reduced, and the refractive index and the haze are at an appropriate level. Is formed to have an advantage that can implement excellent index matching, excellent visibility and excellent optical properties. In addition, by reducing the average particle diameter of the inorganic particles to an appropriate level as described above, the annealing process involved in forming the conductive layer on the upper portion of the low refractive index layer may be more easily performed, thereby lowering the electrical resistance of the conductive layer. Therefore, excellent electrical conductivity can be achieved.

The low refractive index composition may include, for example, about 0.5 parts by weight to about 20 parts by weight, and specifically about 7 parts by weight to about 13 parts by weight, based on about 100 parts by weight of the organopolysiloxane. can do. By including in the above range it is possible to implement the excellent anti-blocking performance and low refractive index while maintaining the haze at an appropriate level to implement excellent optical properties and excellent visibility at the same time.

Specifically, when the inorganic particles are included in less than about 0.5 parts by weight, the antiblocking performance may not be sufficiently realized. When the inorganic particles are included in more than about 20 parts by weight, the electrical properties may be impaired after the conductive layer is formed. There is a problem that can be reduced.

The inorganic particles may include, for example, at least one particle selected from the group consisting of silica particles, alumina particles, zirconium oxide particles, titanium oxide particles, antimony oxide particles, and combinations thereof.

Conventionally, inorganic particles in the form of powder were mixed with the composition for hard coating, thereby agglomeration or precipitating during the coating process, thereby preventing uniformity in blocking performance and low refractive index.

In one embodiment, the low refractive index composition may include inorganic particles in the form of a sol, that is, inorganic particles containing sol to improve the dispersibility, thereby achieving both the anti-blocking performance and low refractive index at a uniform level. Can be. That is, the inorganic particles may be dispersed in a dispersion medium and included in the form of a dispersion sol.

For example, the inorganic particles may be, for example, dispersed in a dispersion medium such as water or an organic solvent, and may be included in a colloidal phase in which solid content of the inorganic particles is about 5 wt% to about 40 wt%, but is not limited thereto. It doesn't happen. Organic solvents usable as the dispersion medium include alcohols such as methanol, isopropyl alcohol, IPA, ethylene glycol, butanol, etc .; Ketones such as methyl ethyl ketone and methyl iso butyl ketone (MIBK); Aromatic carbon hydrogens such as toluene and xylene; Amides such as dimethyl formamide, dimethyl acetamide and N-methyl pyrrolidone; Esters such as ethyl acetate, butyl acetate and γ-butyrolactone; Ethers such as tetrahydrofuran and 1,4-dioxane; Or mixtures thereof.

The inorganic particles may have an average diameter of, for example, about 30 nm to about 70 nm, and specifically about 35 nm to about 60 nm.

 The average diameter means the average value of the particle diameters measured for each particle. By having an average diameter within the above range, the protrusions are sufficiently formed in the low refractive layer, so that excellent blocking prevention performance can be realized, and even when a fine uneven shape is generated, excellent visibility can be realized without lowering the visibility during etching of the conductive layer. Since the electrical resistance is not generated in the layer and excellent electrical conductivity can be realized, the role of the undercoat layer under the conductive layer can be sufficiently performed.

Specifically, when the average diameter is less than about 30 nm, the particle size is too small to exhibit blocking prevention performance, and when the average diameter is greater than about 70 nm, the annealing process is essentially applied in the process of forming the conductive layer on the low refractive index layer. The average diameter of the inorganic particles is too large to interfere with the annealing process, thereby increasing the electrical resistance of the conductive layer, thereby lowering the electrical conductivity, thereby causing malfunction of the touch screen panel, and increasing the haze. There is a problem that physical properties are lowered. In addition, the adhesion to the high refractive index layer and the conductive layer laminated on both surfaces of the low refractive index layer can be further lowered.

In one embodiment, the low refractive index composition may include, for example, about 10% to about 80% by weight of the organopolysiloxane. By including a content within the above range can be formed at a low level of the refractive index can be easily formed a low refractive index layer.

The organopolysiloxane is an alkyl group of 1 to 18 carbon atoms, an alkoxy group of 1 to 18 carbon atoms, an ester group of 2 to 6 carbon atoms, an epoxy group of 2 to 12 carbon atoms, an alkenyl group of 2 to 12 carbon atoms, 6 carbon atoms It may include at least one functional group selected from the group consisting of 12 to 12 aromatic groups, 3 to 18 carbon atoms, acrylic group, glycidyl group, amine group, thiol group, halogen group and combinations thereof. By including the functional group, the chemical reaction can be easily carried out in various kinds of organic solvents, so that the processability and compatibility are excellent, and coating can be easily performed on various kinds of substrates, and excellent adhesion can be realized.

The aromatic group means a substituent in which all elements of the cyclic substituent have p-orbitals, and these p-orbitals form conjugation. As a specific example, a phenyl group, an aryl group, etc. are mentioned. Further, examples of the halogen group include -F, -Cl, -Br, -I and the like.

In addition, the organopolysiloxane may include a linear structure, a network structure, or both. That is, the organopolysiloxane may be formed in a linear structure by combining in a chain structure by a siloxane bond, that is, Si-O-Si bond, may be formed in a network structure by combining in a three-dimensional structure, including all It may be formed in a structure to. In addition, the network structure may include a structure partially opened by the functional group, and specifically, the structure of the network structure is partially broken by the functional group may include an open structure.

When the organopolysiloxane includes a linear structure, the solidification rate is low, so that excellent process stability can be realized, and when the coating is applied to the substrate, the flatness is more excellent. For example, indium tin oxide (ITO) when forming a conductive layer ) Crystallization can be facilitated to improve the electrical conductivity. On the other hand, when the organopolysiloxane includes a reticulated structure, due to its structural characteristics, excellent chemical resistance and excellent solvent resistance can be realized, and thus, acidic or basic used in an etching process or a washing process required for forming a conductive layer. Unaffected by chemicals, excellent stability can be achieved.

The organopolysiloxane may have a weight average molecular weight of about 3,000 g / mol to about 55,000 g / mol. By having a weight average molecular weight within the above range is advantageous in terms of thickness control when forming the low refractive layer, it is possible to easily implement the effect of maintaining a uniform surface roughness.

The organopolysiloxane may be formed by a sol-gel reaction of a raw material composition comprising a silane compound of Formula 1 and a silane compound of Formula 2 below:

[Formula 1]

R ¹ _x Si (OR ² ) _4-x

[Formula 2]

Si (OR ³ ) ₄

In Chemical Formula 1, R ¹ is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and having 6 to 12 carbon atoms Group, an acryl group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R ² and R ³ is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1, 2, or 3.

The aromatic group means a substituent in which all elements of the cyclic substituent have p-orbitals, and these p-orbitals form conjugation. As a specific example, a phenyl group, an aryl group, etc. are mentioned. Further, examples of the halogen group include -F, -Cl, -Br, -I and the like.

In the sol-gel reaction, for example, precursor molecules such as a silane compound may undergo a hydrolysis reaction, a condensation reaction, a dehydration condensation reaction, a hydrolysis-polycondensation reaction, and the like to crosslink with a linear structure or a three-dimensional network structure. It may mean a reaction to form.

The organopolysiloxane may be formed by chemical reaction between the silane compounds during the sol-gel reaction of the raw material composition. For example, the silane compounds of Formula 1 may react with each other, or the silane compounds of Formula 2 may react with each other, or the silane compound of Formula 1 and the silane compound of Formula 2 may react with each other, or a combination thereof. The organopolysiloxane may be formed by reacting in a form.

The chemical reaction may include, for example, at least one selected from the group consisting of a hydrolysis reaction, a condensation reaction, a dehydration condensation reaction, a hydrolysis-polycondensation reaction, and a combination thereof. Silane bonds, that is, Si-O-Si bonds, may be formed between the silane compound of Formula 1, the silane compound of Formula 2, or both, and thus the organopolysiloxane may be formed.

For example, the silane compound of Formula 1 may be trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimeth Methoxysilane, n-propyltriethoxysilane, isobutyltriethoxysilane, cyclohexyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyl tri Methoxysilane allyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, trichloromethylsilane, trichlorochloromethyl silane, trichloro dichloromethyl silane, tetrachloro Silane, dimethoxydimethyl silane, triacetoxy vinylsilane, trichlorooctadecylsilane trichlorooctylsilane, acryloxypropyl trimethoxy silane, acryloxypropyl trie Cysilane, methacryloxypropyl trimethoxy silane, methacryloxypropyl triethoxy silane, methacryloxymethyl trimethoxy silane, methacryloxymethyl triethoxy silane, methacryloxymethyl methyl dimethoxy silane, methacryl Oxymethyl methyl diethoxy silane, methacryloxypropyl methyl dimethoxy silane, methacryloxypropyl methyl diethoxy silane, methacryloxypropyl dimethyl methoxy silane, methacryloxypropyl dimethyl ethoxy silane, epoxycyclohexylethyl trimethoxy Silane, glycidylpropyl trimethoxy silane, glycidylpropyl methyl diethoxy silane, glycidylpropyl triethoxy silane, stearyl trimethoxy silane, aminoethyl trimethoxy silane, aminopropyl Trimethoxy silane, aminoethyl triethoxy silane, aminopropyl triethoxy silane, triethoxysilyl di At least one selected from the group comprising methyl butylidene propyl amine, phenyl aminopropyl trimethoxy silane, and combinations thereof.

The silane compound represented by Formula 2 is tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxy And at least one selected from the group comprising silanes, and combinations thereof.

In one embodiment, the weight ratio of the silane compound of Formula 1 to the silane compound of Formula 2 included in the raw material composition may be about 1: 5 to about 1:99. By including in a weight ratio within the above range it is possible to appropriately adjust the content of the organic portion and the inorganic portion contained in the organopolysiloxane to implement excellent index matching, excellent adhesion and oxidation resistance. Specifically, if the ratio is less than about 1: 5, the organic portion may be so large that the coating may be damaged by the basic chemicals available in the washing process, thereby changing the index matching. Too much of the coating's flexibility can be degraded, resulting in reduced adhesion and oxidation.

The raw material composition may include, for example, about 1 wt% to about 19 wt% of the silane compound of Formula 1, but is not limited thereto.

In one embodiment, the inorganic particles may be further mixed in the composition before the sol-gel reaction. When the inorganic particles are further mixed with the composition in which the organopolysiloxane is already formed, the dispersibility may be reduced. Thus, the low refractive index composition is the inorganic particles between the organopolysiloxane which is a result of the reaction between the silane compounds of the formula (1) by a sol-gel reaction of the composition containing both the silane compound of the formula (1) and the inorganic particles Can be effectively dispersed, thereby achieving a more uniform level of anti-blocking performance, low refractive index and optical properties.

In general, when the conductive layer is formed on the low refractive layer, the conductive layer film formation is performed by, for example, a sputtering method under vacuum conditions.

Under the vacuum conditions, when the low refractive index composition contains the monomolecular alkoxysilane compound, the monomolecular alkoxysilane compound, which is a volatile organic compound (VOC), is discharged from the low refractive index layer formed therefrom, thereby conducting the conductive. The layer formation may interfere with the annealing process, thereby increasing the electrical resistance of the conductive layer, thereby lowering the electrical conductivity. In addition, under high temperature and high humidity conditions, the migration phenomenon of the monomolecular alkoxysilane compound may occur in the low refractive layer, and the haze may be increased to decrease the surface properties, thereby reducing optical properties and electrical conductivity. have.

Thus, in one embodiment, the low refractive index composition may not include or further include a substituted or unsubstituted monomolecular alkoxysilane compound. Specifically, it may not include a substituted or unsubstituted single-molecule alkoxysilane compound, and thus, when forming a conductive layer, the mono-molecular alkoxysilane compound, which is a volatile organic compound, is not discharged, and thus an annealing process may be easily performed, thereby providing excellent electrical The conductivity can be implemented, and at the same time, it can prevent the transition phenomenon at high temperature and high humidity conditions, thereby maintaining the haze and surface properties to implement excellent reliability.

As used herein, unless otherwise defined, a "substituted" halogen atom (F, Cl, Br, or I), hydroxy group, nitro group, cyano group, amino group, carboxyl group, alkyl group having 1 to 30 carbon atoms; Cycloalkyl groups having 3 to 30 carbon atoms; Aryl groups having 6 to 30 carbon atoms; Or an alkoxy group having 1 to 30 carbon atoms. The alkyl group may be straight or branched.

The monomolecular alkoxysilane compound is meant to include all kinds known in the art, for example, may include at least one selected from the kind of silane compound of Formula 1, but is not limited thereto.

The low refractive index composition may further include at least one selected from the group consisting of an acid catalyst, water, an organic solvent, and a combination thereof.

As the acid catalyst, for example, an inorganic acid or an organic acid may be used, and specifically, nitric acid, hydrochloric acid, sulfuric acid, acetic acid, or the like may be used.

The organic solvent may be, for example, alcohols such as methanol, isopropyl alcohol, IPA, ethylene glycol, butanol, etc .; Ketones such as methyl ethyl ketone and methyl iso butyl ketone (MIBK); Esters such as ethyl acetate, butyl acetate and γ-butyrolactone; Ethers such as tetrahydrofuran and 1,4-dioxane; And at least one selected from the group consisting of a combination thereof.

Transparent conductive film

In another embodiment of the present invention, it provides a transparent conductive film comprising a low refractive index layer formed by the low refractive index composition. The low refractive index composition is as described above in one embodiment, the low refractive index layer is provided with anti-blocking performance may serve as an anti-blocking low refractive layer.

Accordingly, the transparent conductive film including the low refractive index layer provides excellent blocking prevention performance, while in the coating process of the low refractive index composition, defect rate of the surface appearance is reduced, refractive index and haze are formed at an appropriate level, and excellent index matching is achieved. There is an advantage that can implement the properties, excellent visibility and excellent optical properties. In addition, by reducing the average particle diameter of the inorganic particles to an appropriate level as described above, the annealing process involved in forming the conductive layer on the upper portion of the low refractive index layer may be more easily performed, thereby lowering the electrical resistance of the conductive layer. Therefore, excellent electrical conductivity can be achieved.

For example, the low refractive index layer may be formed by applying the low refractive index composition to the upper portion of the high refractive index layer, which may be included in the lower portion, as described below, and then performing a thermosetting reaction. Application of the low refractive index composition may be, for example, gravure coating, slot die coating, spin coating, spray coating, bar coating, dip coating, or the like. It is not limited to this

In addition, the thermosetting reaction may be performed by heat treatment at a temperature of about 100 ℃ to about 170 ℃, but is not limited thereto.

In addition, the aging process may be further performed after the thermosetting reaction, and the aging process may be performed according to conditions and methods known in the art.

The low refractive index layer may have fine unevenness formed on an upper surface thereof, and the fine unevenness may be formed by the inorganic particles. For example, a portion of the inorganic particles may protrude from the surface of the low refractive index layer to cause the fine unevenness. In some embodiments, other portions of the inorganic particles may be present in a state buried in the low refractive layer. In addition, the average diameter of the inorganic particles may be larger than the thickness of the low refractive layer, thereby forming the fine irregularities more easily.

That is, the fine concavo-convex shape may be formed by inorganic particles having an average diameter of about 30 nm to about 70 nm when the low refractive index composition is applied, and specifically, when the low refractive index composition is applied to the base layer, the inorganic particles Since the average diameter of the larger than the thickness of the low refractive index layer is protruded, the fine concave-convex shape can be formed more easily, and thus the low refractive layer can implement a better blocking prevention performance.

The low refractive layer may have a thickness of about 10 nm to about 50 nm. When the thickness of the low refractive index layer is less than about 10 nm, there is a fear of visibility deterioration due to optical interference, and when the thickness of the low refractive index layer is greater than about 50 nm, the transmittance is too low so that optical properties may be degraded. It can achieve excellent visibility and excellent optical properties by maintaining high light transmittance and low haze while satisfying the properties.

In addition, the refractive index of the low refractive index layer may be about 1.40 to about 1.50. By having a low level of refractive index within the above range, both the visibility and optical properties of the transparent conductive film together with the high refractive index layer can be adjusted to an excellent level.

1 schematically shows each cross section of two examples, (a) and (b), of a transparent conductive film according to another embodiment of the present invention.

The transparent conductive film may further include a high refractive index layer and a base layer sequentially below the low refractive layer, and may further include a conductive layer on the low refractive layer. Specifically, referring to FIG. 1A, a high refractive layer, the low refractive layer, and a conductive layer may be sequentially included on one surface of the base layer.

The high refractive index layer serves to improve insulation properties and transmittance between the substrate layer and the conductive layer. The high refractive layer may be formed of a material including an inorganic material, an organic material, or both. In the inorganic material is in, for example, SiO _2, MgF _2, and the like _{Al 2 O 3, NaF, Na} 3 AlF 6, LiF, CaF 2, BaF 2, LaF 3, CeF 3, wherein the organic material is, for example , Melamine resins, alkyd resins, urethane resins, acrylic resins, siloxane based polymers, organosilane condensates and the like can be used.

For example, the high refractive layer may be formed using a coating method known in the art, such as thermal curing, photocuring, spraying, sputtering, etc. after coating according to the type of the material.

In addition, for example, the thickness of the high refractive layer may be about 15nm to about 100nm. By maintaining the thickness of the high refractive layer can be improved excellent transmittance and visibility, it is possible to reduce the occurrence of cracks and curl (Curl) due to the stress.

Also, for example, the refractive index of the high refractive layer may be about 1.65 to about 1.8. By having a high level of refractive index within the above range it is possible to control both the visibility and optical properties of the transparent conductive film with an excellent level with the low refractive index layer.

The base layer is a transparent base layer, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), polypropylene (PP), polyvinyl chloride (PVC), polyethylene (PE), polymethyl methacrylate (PMMA), ethylene vinyl alcohol (EVA), polyvinyl alcohol (PVA) and combinations thereof may be formed of a material comprising at least one selected from the group consisting of However, it is not limited thereto.

In addition, the substrate layer may be a film of a single layer or a multi-layer structure, the total thickness of the substrate layer may be, for example, about 20㎛ to about 500㎛.

The conductive layer may include, for example, indium tin oxide (ITO), zinc oxide (ZnO), zinc tin oxide (ZTO), fluorine-doped tin oxide (FTO), It may include at least one selected from the group consisting of silver nanowires (Al-doped ZnO, AZO), and combinations thereof.

The conductive layer may have a thickness of about 5 nm to about 50 nm, and by maintaining the thickness of the conductive layer in the range, excellent optical properties may be realized without excessively increasing the total thickness of the transparent conductive film.

It may further include a hard coating layer in contact with one side or both sides of the base layer, accordingly the refractive index is properly adjusted while supporting and protecting the low refractive index layer and the high refractive index layer to improve the hardness of the transparent conductive film Phenomenon such as light interference may occur, and the index matching may be more easily satisfied.

The hard coating layer may be formed by photocuring a hard coating layer composition including, for example, at least one selected from the group consisting of an ultraviolet curable resin, nano inorganic particles having an average diameter of about 1 nm to about 30 nm, a photopolymerization initiator, and a combination thereof. The nano-inorganic particles having an average diameter of about 1 nm to about 30 nm may be embedded in the hard coating layer to improve surface hardness, but hardly prevent blocking performance. Specifically, in order to provide the anti-blocking performance to the hard coating layer, the average diameter of the inorganic particles should be about 1 μm or more. In the case of including the inorganic particles having a large average diameter as described above, the surface appearance defects may occur while coating the haze. It may increase too much to deteriorate the optical properties, and when it is produced continuously in the manufacturing process, it may be difficult to have uniform physical properties for each product.

The hard coating layer may have a thickness of about 900 nm to about 2000 nm. If the thickness of the hard coating layer is less than about 900nm can not implement the surface hardness of the transparent conductive film to a sufficient level, the durability may be low, if the hard coating layer is greater than about 2000nm there is a fear that the hard coating layer curling (Curling), the range By having a thickness of the curling can be prevented while implementing an excellent surface hardness.

The writing rate of the hard coat layer may be about 1.45 to about 1.7, but is not limited thereto.

In another embodiment, the light transmittance of the transparent conductive film may be about 85% or more, and the haze may be about 0.1% to about 0.8%, and specifically, the light transmittance may be about 87% to about 92%. By having light transmittance and haze in the above range it is possible to implement excellent optical properties while implementing the index matching. In the present specification, the light transmittance and the haze mean a value measured based on, for example, a transparent conductive film having a thickness of about 100 μm.

In another embodiment of the present invention, preparing a raw material composition comprising a silane compound of Formula 1, a silane compound of Formula 2 and inorganic particles having an average diameter of 30nm to 70nm; Proceeding with the sol-gel reaction with respect to the raw material composition to produce a low refractive index composition provides a method for producing a low refractive index composition comprising:

[Formula 1]

R ¹ _x Si (OR ² ) _4-x

[Formula 2]

Si (OR ³ ) ₄

In Formula 1, R 1 is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and an aromatic group having 6 to 12 carbon atoms , An acrylic group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R2 and R3 is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1 , 2, or 3. That is, the low refractive index composition described above in one embodiment may be prepared by the preparation method, and the silane compound of Formula 1 and the silane compound of Formula 2 are the same as described above in one embodiment.

For example, the raw material composition may be prepared by mixing the inorganic particles in an amount of about 0.5 parts by weight to about 20 parts by weight based on 100 parts by weight of the total of the silane compound of Formula 1 and the silane compound of Formula 2, and specifically, May comprise about 7 parts by weight to about 13 parts by weight.

In addition, the raw material composition may be prepared by further mixing at least one selected from the group consisting of an acid catalyst, water, an organic solvent, and a combination thereof, and the acid catalyst and the organic solvent are as described above in one embodiment.

During the sol-gel reaction, the silane compounds may be chemically reacted with each other to form an organopolysiloxane, and the organopolysiloxane and the chemical reaction are the same as described above in one embodiment.

In addition, the total content of the sum of the content of each of the silane compound of Formula 1 and the silane compound of Formula 2 included in the raw material composition such that the low refractive index composition comprises about 10% to about 80% by weight of the organopolysiloxane Can be adjusted.

For example, the raw material composition may be prepared such that a weight ratio of the silane compound of Formula 1 to the silane compound of Formula 2 is about 1: 5 to about 1:99. By mixing in a weight ratio within the above range it is possible to appropriately adjust the content of the organic portion and the inorganic portion included in the formed organopolysiloxane can implement excellent index matching, excellent adhesion and oxidation resistance. Specifically, if the ratio is less than about 1: 5, the organic portion may be so large that the coating may be damaged by the basic chemicals available in the washing process, thereby changing the index matching. Too much of the coating's flexibility can be degraded, resulting in reduced adhesion and oxidation.

The raw material composition may be prepared such that the silane compound of Formula 1 is included, for example, in about 1% by weight to about 19% by weight, but is not limited thereto.

In the preparation method, for example, the sol-gel reaction may be performed by stirring at a temperature of about 20 ° C. to about 60 ° C. for about 8 hours to about 48 hours, but is not limited thereto. By stirring under the temperature and time conditions within the above range, chemical reactions such as hydrolysis reaction, condensation reaction and the like sufficiently proceed to form the organopolysiloxane more easily.

In addition, after the completion of the sol-gel reaction, the organic solvent may be appropriately mixed and diluted with the low refractive index composition according to the purpose and use of the invention within the scope of the present invention. The organic solvent is as described above in one embodiment.

The following presents specific embodiments of the present invention. However, the embodiments described below are merely for illustrating or explaining the present invention in detail, and thus the present invention is not limited thereto.

<Production example>

Preparation Example 1-1. Low refractive composition

1% by weight of trimethoxy (methyl) silane and 15% by weight of tetra-ethoxyorthosilicate (TEOS), silica particle dispersion sol (ILC, MEK-ST-up), water, ethanol and 1M with an average diameter of 50 nm Nitric acid was mixed to prepare a raw material composition, and the raw material composition included 10 parts by weight of the silica particles based on 100 parts by weight of the total of the trimethoxy (methyl) silane and the tetra-ethoxy orthosilicate (TEOS).

Subsequently, the raw material composition was stirred at 40 ° C. for 24 hours to proceed with a sol-gel reaction to prepare a low refractive composition, and the trimethoxy (methyl) silane and the tetra-ethoxy orthosilicate in the low refractive composition Organopolysiloxanes were formed by chemical reaction between silane compounds consisting of (TEOS).

Specifically, the low refractive index composition included 30% by weight of the organopolysiloxane, and included 10 parts by weight of the silica particles based on 100 parts by weight of the organopolysiloxane.

Preparation Example 1-2. Low refractive composition (average diameter 30nm silica particle dispersion sol is used)

A low refractive index composition was prepared in the same manner as in Preparation Example 1-1, except that an average diameter of 30 nm silica particle dispersion sol (ILC, MEK-ST) was used.

Preparation Example 1-3. Low refractive composition (average diameter 70nm silica particle dispersion sol is used)

A low refractive index composition was prepared in the same manner as in Preparation Example 1-1, except that an average diameter of 70 nm silica particle dispersion sol (ILC, IPAST-up) was used.

Preparation Example 1-4. Low refractive composition (average diameter 20nm silica particle dispersion sol is used)

A low refractive index composition was prepared in the same manner as in Preparation Example 1-1, except that silica particle dispersion sol having a mean diameter of 20 nm (ILC, IPAST) was used.

Preparation Example 1-5. Low refractive composition (average diameter 200nm silica particle dispersion sol is used)

A low refractive index composition was prepared in the same manner as in Preparation Example 1-1, except that silica particle dispersion sol (ILSIN, MEK20) having an average diameter of 200 nm was used.

Preparation Example 1-6. Low refractive composition (does not mix silica particles)

A low refractive index composition was prepared in the same manner as in Preparation Example 1-1, except that silica particles were not mixed.

Preparation Example 2 High Refractive Composition

36 parts by weight of an ultraviolet curable acrylate (trade name HX-920UV, Kyoeisha), 60 parts by weight of high refractive nanoparticles (ZrO2 nanoparticles), and 4 parts by weight of a photopolymerization initiator (trade name Irgacure-184, BASF) based on 100 parts by weight of total solids And diluted with diluent solvent methyl ethyl ketone (MEK) to prepare a high refractive index composition (refractive index 1.68) of 5% solids.

Preparation Example 3 Composition for Hard Coating

20 parts by weight of dipentaerythritol hexaacrylate, 60 parts by weight of ultraviolet curable acrylate (trade name HX-920UV, Kyoeisha), 15 parts by weight of silica fine particles (trade name XBA-ST, Ilsan Chemical), and photopolymerization initiator based on 100 parts by weight of total solids 5 parts by weight of Irgacure-184 (Ciba) was mixed and diluted with a diluting solvent methyl ethyl ketone (MEK) to prepare a composition for hard coating (refractive index 1.50) having a solid content of 45%.

<Examples and Comparative Examples>

Example 1

The hard coating layer composition of Preparation Example 3 was coated on a 50 μm PET film using a Meyer bar to have a dry film thickness of 1.5 μm, and cured by irradiating 300mJ UV light with 180W high pressure mercury or the like to include a hard coating layer on the cross section. The film was produced.

Then, using the high refractive index composition prepared in Preparation Example 2 on the top of the hard coating layer was applied so that the dry film thickness is 50nm, and cured by irradiation with ultraviolet light of 300mJ with 180W high-pressure mercury lamp to form a high refractive index layer.

Subsequently, using a low refractive index composition prepared in Preparation Example 1-1 on the high refractive layer to apply a dry film thickness of 20nm, and cured for 1 minute in 150 ℃ oven to form a low refractive layer. Next, indium tin oxide was deposited on the low refractive layer by using an ITO target of indium: tin = 95: 5, and then subjected to an annealing process by applying an annealing process at 150 ° C. for 1 hour. The transparent conductive film was produced by forming a layer (ITO layer).

Example 2

A transparent conductive film was prepared in the same manner as in Example 1, except that the low refractive layer was formed using the low refractive composition of Preparation Example 1-2.

Example 3

A transparent conductive film was prepared in the same manner as in Example 1 except that the low refractive layer was formed using the low refractive composition of Preparation Example 1-3.

Comparative Example 1

A transparent conductive film was prepared in the same manner as in Example 1, except that the low refractive layer was formed using the low refractive composition of Preparation Example 1-4.

Comparative Example 2

A transparent conductive film was prepared in the same manner as in Example 1, except that the low refractive layer was formed using the low refractive composition of Preparation Example 1-5.

Comparative Example 3

A transparent conductive film was prepared in the same manner as in Example 1 except that the low refractive layer was formed using the low refractive composition of Preparation Example 1-6.

Experimental Example

The physical properties of each of the transparent conductive films according to Examples 1-3 and Comparative Examples 1-3 and each of the low refractive layers included therein were evaluated and listed in Table 1 below.

(Blocking prevention performance)

Measuring method: After cutting the transparent conductive film of each of the Examples and Comparative Examples to the size of 10cm x 10cm (width X length) to prepare 10 specimens, and then laminated the 10 specimens, the film of the 10-layer structure formed according to the metal plate In between, and placed on top of the metal plate placed on the top using a 5kg weight under pressure at a temperature of 50 ℃ for 24 hours and then taken out to remove the film of the 10-layer structure one by one to evaluate the anti-blocking performance. The case where the film is well separated and the blocking prevention performance is excellent by maintaining the physical properties of the transparent conductive film is marked as “○”, and the film is not separated well so that the physical property of the transparent conductive film is degraded and the blocking prevention performance is inferior. The case is marked with "Ⅹ".

(Index matching)

Measuring method: The surface appearance of each of the transparent conductive films of Examples and Comparative Examples was visually observed to evaluate whether the pattern formed of the conductive material inside the conductive layer was visible. When the pattern formed of the conductive material is not visible at all, the index matching or visibility is excellent, and the case is displayed as "○". It was.

(Coating property)

Measuring method: As described above in Examples 1-3 and Comparative Examples 1-3, after forming a low refractive layer in each of the high refractive layer, such as white turbidity, cracks or partial aggregation in the surface appearance of each low refractive layer It was observed by the naked eye to evaluate the coating property. Specifically, the case where the coating property is excellent due to no white cloud, crack, or partial agglomeration does not occur is indicated as “○”, and the case where the coating property is normal due to the low level is indicated as “△”, and is markedly generated. In this case, the inferior coating property was indicated by "X".

(Electrical conductivity)

Measuring method: After conducting the hardening process after the conductive layer was formed, the electrical resistance was measured by using an electrical resistance measuring instrument (MITSUBISHI CHEMICAL, LORESTA-GP [MCP-T610]) to evaluate the electrical conductivity. The better the electrical conductivity is. When the sheet resistance is measured to be 150Ω / □ or less and the electrical conductivity is excellent, it is marked as “○”, and it is measured to be 150 ~ 170Ω / □, and the normal case is marked as “△” and is measured to be 170Ω / □ or more. Inferior cases are marked with “X”.

(Light transmittance and haze)

Measuring method: Each transparent conductive film was measured using a hazemeter (Nippon Denshoku, NDH 5000). The thickness of the said transparent conductive film was about 100 micrometers.

Table 1 Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Average diameter of silica particles (nm) 50 30 70 20 200 - Anti-blocking performance ○ △ ○ X ○ X Index matching ○ ○ ○ ○ △ △ Coating ○ ○ ○ ○ △ △ Electrical conductivity ○ ○ △ ○ X ○ Light transmittance (%) 89.2 89.5 88.9 89.5 87.9 89.5 Haze (%) 0.4 0.4 0.5 0.3 1.1 0.3

As shown in Table 1, the transparent conductive film according to Examples 1 to 3 was evaluated to have almost excellent physical properties, and in particular, in the case of Example 1, the anti-blocking performance, the index matching property, and the electrical conductivity were simultaneously implemented. It was clearly confirmed.

On the other hand, in the transparent conductive films according to Comparative Examples 1 and 3, the silica particles did not interfere with the annealing process when the conductive layer was formed, and thus the electrical conductivity before the distribution process was good, but the anti-blocking performance was particularly low. Therefore, when rolled up or rolled up, or when a plurality of films are stacked and distributed, they stick to each other and are damaged in the process of being unfolded or peeled off for application to a touch screen panel, etc., thereby significantly reducing the performance of the transparent conductive film. It can be clearly expected that the role as the transparent conductive film cannot be properly performed. Moreover, in the case of the transparent conductive film which concerns on the comparative example 2, the index matching property and coating property were also evaluated to be lower than the comparative example 1.

In addition, although the transparent conductive film according to Comparative Example 2 was evaluated to have a moderate index matching property and coating property, the haze was inferior and the optical properties were low, and the annealing process was interrupted by the silica particles during the formation of the conductive layer. It has been estimated that the electrical conductivity is increased and the electrical conductivity is markedly low, and therefore, the role as a transparent conductive film cannot be properly performed.

Claims (19)

Organopolysiloxane and inorganic particles having an average diameter of 30 nm to 70 nm Low refractive composition. The method of claim 1, 0.5 to 20 parts by weight of the inorganic particles based on 100 parts by weight of the organopolysiloxane Low refractive composition. The method of claim 1, The organopolysiloxane is an alkyl group of 1 to 18 carbon atoms, an alkoxy group of 1 to 18 carbon atoms, an ester group of 2 to 6 carbon atoms, an epoxy group of 2 to 12 carbon atoms, an alkenyl group of 2 to 12 carbon atoms, 6 carbon atoms At least one functional group selected from the group consisting of 12 to 12 aromatic groups, 3 to 18 carbon atoms, an acryl group, a glycidyl group, an amine group, a thiol group, a halogen group, and a combination thereof Low refractive composition. The method of claim 1, The organopolysiloxane includes a linear structure, a network structure, or both Low refractive composition. The method of claim 1, The organopolysiloxane is formed by a sol-gel reaction of a composition comprising a silane compound of Formula 1 and a silane compound of Formula 2 Low refractive composition: [Formula 1] R ¹ _x Si (OR ² ) _4-x [Formula 2] Si (OR ³ ) ₄ In Chemical Formula 1, R ¹ is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and having 6 to 12 carbon atoms Group, an acryl group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R ² and R ³ is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1, 2, or 3. The method of claim 5, Before the sol-gel reaction, the inorganic particles are further mixed and included in the composition. Low refractive composition. The method of claim 1, The organopolysiloxane has a weight average molecular weight of 3,000 g / mol to 55,000 g / mol Low refractive composition. The method of claim 1, The inorganic particles include at least one particle selected from the group consisting of silica particles, alumina particles, zirconium oxide particles, titanium oxide particles, antimony oxide particles, and combinations thereof. Low refractive composition. The method of claim 1, It does not contain a substituted or unsubstituted single molecule alkoxysilane compound, or further comprises Low refractive composition. The transparent conductive film containing the low refractive layer formed by the low refractive composition of any one of Claims 1-9. The method of claim 10, The low refractive layer is formed with fine irregularities on the upper surface, The fine irregularities are formed by the inorganic particles Transparent conductive film. The method of claim 10, The thickness of the low refractive layer is 10nm to 50nm Transparent conductive film. The method of claim 10, The low refractive index layer has a refractive index of 1.40 to 1.50 Transparent conductive film. The method of claim 10, Further comprising a high refractive index layer and a base layer sequentially below the low refractive layer, Further comprising a conductive layer on top of the low refractive index layer Transparent conductive film. The method of claim 14, Further comprising a hard coating layer in contact with one side or both sides of the base layer Transparent conductive film. The method of claim 10, Light transmittance of 85% or more and haze of 0.1% to 0.8% Transparent conductive film. Preparing a raw material composition including the silane compound of Formula 1, the silane compound of Formula 2, and inorganic particles having an average diameter of 30 nm to 70 nm; And Preparing a low refractive index composition by performing a sol-gel reaction on the raw material composition; Method for producing a low refractive index composition comprising: [Formula 1] R ¹ _x Si (OR ² ) _4-x [Formula 2] Si (OR ³ ) ₄ In Chemical Formula 1, R ¹ is an alkyl group having 1 to 18 carbon atoms, an ester group having 2 to 6 carbon atoms, an epoxy group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and having 6 to 12 carbon atoms Group, an acryl group having 3 to 18 carbon atoms, a glycidyl group, an amine group, a thiol group or a halogen group, and each of R ² and R ³ is independently H or an alkyl group having 1 to 18 carbon atoms, and x is 1, 2, or 3. The method of claim 17, To prepare the raw material composition by mixing the inorganic particles in 0.5 to 20 parts by weight based on 100 parts by weight of the total of the silane compound of Formula 1 and the silane compound of Formula 2 Process for the preparation of low refractive composition. The method of claim 17, The organopolysiloxane is formed by chemical reaction between the silane compounds during the sol-gel reaction. Process for the preparation of low refractive composition.

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