KR20100112740A - Low reflection film - Google Patents

Abstract

PURPOSE: A low reflection film is provided to economically produce the low reflection film by avoid using an expensive metal oxide additive, and to secure the excellent scratch prevention property. CONSTITUTION: A low reflection film includes a high refractive index hard coating layer(20) and a low refractive index layer(30) successively laminated on one side of a substrate film(10). The surface of the low refractive index layer includes a minute concavo-convex structure. The arithmetic average roughness of the minute concavo-convex structure is 0.0001~0.005 microns. The thickness of the high refractive index hard coating layer is 1~50 microns.

Description

Low reflection film {LOW REFLECTION FILM}

The present invention relates to a low reflection film, and more particularly, to provide a low reflection film in which a hard coating layer adjusted to a high refractive index and a low refractive index layer are laminated on a base film in a two-layer structure, wherein a hard coating layer and a low refractive index layer are provided. By adjusting the surface roughness of the low, it relates to a low reflection film that can improve the surface hardness, scratch resistance and fingerprint removal function than the conventional low reflection film.

Various displays, such as cathode ray tube (CRT), liquid crystal display (LCD), and plasma display (PDP), are electric signals that are represented on the screen. Most of them use high voltage, so static electricity, electromagnetic waves and external light reflection on the surface Wake up to harm the health of the user, as well as halve the visual effect or cause eye fatigue. Accordingly, the low reflection film which prevents the external appearance from being reflected well is disposed on the surface of the screen display device to make the image quality much clearer and to obtain a screen without fatigue to the user's eyes.

In general, the low reflection film of the display forms a multi-layer structure [PCT JP2003-008535], for example, a three-layer structure composed of a hard coating layer, a high refractive index layer and a low refractive index layer on the base film (Fig. 2) and 4 layers structure composed of hard coating layer, middle refractive index layer, high refractive index layer and low refractive index layer (FIG. 3) and 5 layers structure composed of hard coating layer, high refractive index layer, low refractive index layer, high refractive index layer and low refractive index layer ( The low reflection film of FIG. 4) is known.

The hard coating layer is positioned to be in contact with the base film to improve the hardness of the base film, the high refractive index layer, the low refractive index layer and the middle refractive index layer is laminated on the hard coating layer as a layer for adjusting the refractive index. At this time, in order for the low reflection film to sufficiently exhibit the function of external light reflection, it is important that the refractive index of the low refractive index layer is lower than the refractive index of the layer closer to the substrate than the low refractive index layer.

In general, the low reflection film is composed of a multi-layered structure for controlling the refractive index, but the more layers are laminated in view of the productivity, cost and reflection reduction effect of the low reflection film is advantageous. In addition, since the low-reflection film is located at the outermost part of the display product, in addition to the function of reducing external light reflection, additional functions such as anti-scratch, anti-pollution, and antistatic are required for protecting and enhancing the product. A refractive index layer is known. Examples thereof include high refractive index hard coating layers imparted with the functions of antistatic and hard coating layers and low refractive index layers imparted with fouling resistance.

However, when manufacturing a refractive index layer that plays more than one role, the materials that can be used are limited and manufacturing costs are high due to the inevitable use of expensive selected materials. In addition, there is a limit that the final optical characteristics, transmittance, haze and UV resistance characteristics are lower than the refractive index layer prepared in consideration of only the refractive index. In particular, in the case of a high refractive index hard coating layer, a high refractive index is required and at the same time a large amount of particles selected to impart the antistatic properties required for large display products, the surface roughness of the coating layer tends to increase. The low refractive index layer also tends to increase the surface roughness of the coating layer as a large amount of particles having low refractive index are used to lower the final reflectance of the display product.

In recent years, efforts have been made to improve visibility, especially in outdoor, by reducing external light reflection in the field of small portable devices such as mobile phones, PDAs, PMPs, and game machines other than large displays such as LCDs and PDP TVs. However, the following problems occur when the commercially available low-reflection films for large displays are applied to portable devices as they are.

First, in the case of a portable device, especially a portable device employing a touch panel, contact by the user's skin occurs much more frequently than a large display. As a result, the possibility of contamination caused by sweat, fingerprints, or the like is significantly increased as compared with a large display. For that reason, there is a greater need for countermeasures against such contamination in portable devices. However, the low reflection films for large display have fine unevenness on the surface due to the particles used in large quantities to satisfy the original optical characteristics as described above, and the unevenness of the unevenness is caused by contamination of fingerprints and the like. It will interfere with removal. In addition, in the case of a portable device, especially when a touch panel is employed, contact with various materials occurs more frequently than a large display in the process of impact and touch with a pen or fingernail for touch. In other words, the ability to prevent scratching by contact with hard and coarse materials is more stringent than that of large displays.

The present invention has been made to solve the above problems and to meet the requirements of the art, the object of the present invention is excellent scratch resistance and fingerprint removal function, and also high due to the addition of existing expensive metal oxide It is to provide a low reflection film that can lower the manufacturing cost.

These and other objects and advantages of the present invention will become more apparent from the following description of a preferred embodiment thereof.

The purpose is that the high refractive index hard coating layer 20 and the low refractive index layer 30 are sequentially stacked on at least one surface of the base film 10, the surface of the low refractive index layer 30 has fine irregularities, Arithmetic mean roughness Ra of the unevenness is 0.0001 µm to 0.005 µm, which is achieved by a low reflection film.

Here, the low refractive index layer 30 is characterized in that it comprises 3 to 15 parts by weight of hollow silica with respect to 100 weight of the binder resin.

Preferably, the low reflection film is characterized in that the haze is less than 3%.

Preferably, the low reflection film is characterized in that the surface hardness of 3H or more.

Preferably, the low reflection film is characterized in that the water contact angle is 80 ° or more.

Preferably, the thickness of the high refractive index hard coating layer 20 is 1 ~ 50㎛, the thickness of the low refractive index layer 30 is characterized in that the 0.01 ~ 1.0㎛.

Preferably, the low refractive index layer 30 is characterized in that it comprises a fluorine-containing copolymer having a vinyl ether structure in the main chain.

Preferably, the low refractive index layer 30 is characterized in that it further contains silica fine particles having a particle diameter of 0.001㎛ 0.2㎛.

Also preferably, the low refractive layer 30 contains a silane coupling agent represented by the following formula (1) or a hydrolyzate thereof or a reactant thereof,

[Formula 1]

R (1) _a R (2) _b SiX _{4- (a + b)}

Here, R (1) and R (2) are each an alkyl group, an alkenyl group, an allyl group, or a hydrocarbon group having a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group to a cyano group, and X is an alkoxyl group , Alkoxyalkoxy group, a hydrolyzable substituent selected from halogen to acyloxy group, a and b are each 0, 1 or 2, and (a + b) is characterized in that 1, 2 or 3.

Preferably, the low refractive layer 30 further contains a fluorine resin or a hydrolysis product thereof having an alkoxysilyl group represented by the following Chemical Formula 2 as a fluorine compound,

[Formula 2]

R (3) _c R (4) _d SiX _{4- (c + d)}

Wherein R (3) and R (4) are each a hydrocarbon group having a fluorine-substituted alkyl group, alkenyl group, allyl group, methacryloxy group, or (meth) acryloyl group, and X is an alkoxyl group or an alkoxyalkoxy group And a hydrolyzable substituent selected from a halogen group or an acyloxy group, c and d are each 0, 1, 2 or 3, and (c + d) is 1, 2 or 3, respectively.

In addition, the low reflection film is characterized in that the increase in reflectance is less than 0.5% before and after light irradiation for 500 hours.

According to the present invention, the surface hardness, scratch resistance and fingerprint removal function is excellent, and also has the effect of lowering the high manufacturing cost according to the existing expensive metal oxide addition.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. These examples are only presented by way of example only to more specifically describe the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples. .

The present inventors have made efforts to solve the above problems, while forming a high refractive index hard coating layer in which the hard coating layer is adjusted to a high refractive index on the base film, the high refractive index hard coating layer adds particles for controlling the refractive index to the hard coating resin component In this case, the size and ratio of the particles are optimally contained, and similarly, even the low refractive index layer laminated on the hard coating layer eliminates the factor of forming excessive unevenness, and thus the surface roughness of the finally completed low reflection film is contaminated by fingerprints or the like. The present invention was completed by confirming that a low-reflection film that can be easily removed and can prevent scratches caused by contact with a pen or the like is made.

1 is a cross-sectional view of a low reflection film according to an embodiment of the present invention, such a low reflection film is a film in which the high refractive index hard coating layer 20 and the low refractive index layer 30 are sequentially laminated on the base film 10 (Hereinafter referred to as 'low reflection film'). In such a low reflection film, an adhesive layer and a release film may be laminated on opposite surfaces of the protective film and the base film 10.

The present invention can provide an excellent low reflection film that improves physical functions such as surface hardness, scratch resistance, and the like by lowering the surface arithmetic mean roughness Ra of the high refractive index hard coating layer and the low refractive index layer. In addition, it is possible to provide a low reflection film that can lower the high manufacturing cost according to the existing expensive metal oxide addition.

In order to achieve this object, the present inventors have intensively studied, and as a result, the high refractive index hard coating layer 20 and the low refractive layer 30 are sequentially stacked on at least one surface of the base film, and the low refractive layer 30 The surface arithmetic mean roughness (Ra) of was found to be composed of an antireflection film that can achieve the object by the configuration of 0.0001 µm to 0.005 µm.

The low reflection film according to the present invention can be applied to an image display device made by adhering to the surface of an image display surface or a front plate.

The base film 10 of the low reflection film according to the present invention preferably has a high light transmittance and a low haze value for use as a display device member (hereinafter referred to as a 'display member'). For example, the light transmittance at a wavelength of 400 to 800 nm is preferably 40% or more, more preferably 60% or more, and the haze value is preferably 5% or less, and more preferably 3% or less. When one or all of these conditions are not satisfied, there is a tendency that the sharpness of an image is lacking when used as a display member. In addition, the upper limit of the light transmittance is about 99.5%, and the lower limit of the haze value is about 0.1% in the point which exhibits such an effect, and is the range which can be produced.

In addition, the said base film 10 of the low reflection film which concerns on this invention is not specifically limited, It can select suitably from the resin material used for a well-known plastic base film, and can use. As such a resin material for the base film, for example, ester, ethylene, propylene, diacetate, triacetate, styrene, carbonate, methylpentene, sulfone, ether ethyl ketone, imide, fluorine, nylon, acrylate, alicyclic olefin Polymers or copolymerized polymers having one selected from the system and the like as the structural unit can be used. Preferably, among these resins, polymers or copolymerized polymers containing one selected from esters such as polyethylene terephthalate, acetates such as triacetyl cellulose, and acrylates such as polymethyl methacrylate are preferred. This is because they are excellent in transparency, strength and uniformity of thickness. In particular, in view of transparency, haze value and mechanical properties, a base film made of a polymer having an ester type as a structural unit is preferable.

Examples of such polyester resins include polyethylene terephthalate, polyethylene-2,6-naphthalate, polybutylene terephthalate, polyethylene-α, and β-bis (2-chlorophenoxy) ethane-4,4'-dicarboxyl. The rate etc. are mentioned. Moreover, these polyester may be copolymerized as long as another dicarboxylic acid component and diol component are 20 mol% or less. Among them, polyethylene terephthalate is particularly preferred in view of comprehensive evaluation of quality, economy and the like. 1 type of these structural resin components may be used, or they may be used together 2 or more types.

Moreover, the base film thickness of the low reflection film which concerns on this invention is although it does not specifically limit, In terms of transparency, a haze value, and a mechanical characteristic, it is 5-800 micrometers normally, Preferably it is 10-250 micrometers. Moreover, what joined two or more films by a well-known method may be sufficient.

In addition, the base film 10 is subjected to various surface treatments (for example, corona discharge treatment, glow discharge treatment, flame treatment, etching treatment, roughening treatment, etc.) before the high refractive index hard coating layer 20 is formed. It may be implemented. Also, in order to promote adhesion, the surface of the base film is coated as a primer layer (for example, polyurethane, polyester, polyester acrylate, polyurethane acrylate, polyepoxy acrylate, titanate compound, etc.). After the coating), the high refractive index hard coating layer 20 may be formed. In particular, the primer coating of a composition comprising a copolymer and a crosslinking agent grafted with an acrylic compound on a hydrophilic group-containing polyester resin is preferred as the base film 10 because of improved adhesiveness and excellent durability such as heat resistance and water resistance. .

Next, the high refractive index hard coating layer 20 of the low reflection film according to the present invention is formed on the base film 10, it is essential to contain an acrylate compound. Such a (meth) acrylate compound improves the solvent resistance and hardness of the film formed by radical polymerization by actinic light irradiation. Specifically, methyl (meth) acrylate, n-butyl (meth) acrylate, polyester (meth) acrylate, lauryl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) Monofunctional acrylate compounds, such as a) acrylate, are mentioned. Moreover, since the solvent resistance etc. improve the polyfunctional (meth) acrylate compound in which two (meth) acryloyl groups are in a molecule | numerator, it is especially preferable in this invention. Specific examples of the polyfunctional (meth) acrylate include pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, Dipentaerythritol (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimetholpropane tri (meth) acrylate, and the like. You may use these monomers 1 type or in mixture of 2 or more types.

In addition, the constituent resin components for forming the high refractive index hard coating layer 20 according to the present invention include alkyl silicates and hydrolyzates thereof, colloidal silica, dry silica, for the purpose of improving the hardness of the high refractive index layer hard coating layer 20. Inorganic particles, such as wet silica and titanium oxide, silica fine particles dispersed in the colloidal form, etc. may be contained.

Although the thickness of the said high refractive index hard coating layer 20 is suitably selected according to a use, it is 1 micrometer-50 micrometers normally, Preferably they are 2 micrometers-30 micrometers. If the thickness of the high refractive index hard coating layer 20 is less than 1 µm, the surface hardness is insufficient to easily cause scratches, and if the thickness exceeds 50 µm, the transparency decreases and the haze value tends to increase, and the cured film It becomes weak, and it is unpreferable because a crack becomes easy to occur in the high refractive index hard coating layer 20 when a film is bent and folded.

In addition, when forming the high refractive index hard coating layer 20 in the low reflection film according to the present invention, an initiator is used to advance the curing of the applied binder component. As said initiator, the apply | coated binder component starts or promotes superposition | polymerization and / or crosslinking reaction by radical reaction, anion reaction, cation reaction, etc., and various conventionally well-known photoinitiators can be used. Specifically, sulfides such as sodium methyldithiocarbamate sulfide, diphenyl monosulfide, dibenzothiazoyl monosulfide and disulfide; Thioxanthone derivatives such as thioxanthone, 2-ethyl thioxanthone, 2-chlorothioxanthone and 2,4-diethyl thioxanthone; Azo compounds such as hydrazone and azobisisobutyronitrile; Diazo compounds such as benzenediazonium salts; Benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, dimethylaminobenzophenone, Michler's ketone, benzyl anthraquinone, t-butyl anthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-amino Aromatic carbonyl compounds such as anthraquinone and 2-chloroanthraquinone; dialkylamino benzoic acid esters such as methyl p-dimethylamino benzoate, ethyl p-dimethylamino benzoate, butyl D-dimethylamino benzoate and isopropyl p-diethylamino benzoate; Peroxides such as benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide and cumene hydroperoxide; Acridine derivatives such as 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine and benzacridin; Phenazine derivatives such as 9,10-dimethylbenzphenazine, 9-methylbenzphenazine, and 10-methoxybenzphenazine; Quinoxaline derivatives such as 6,4 ', 4 "-trimethoxy-2,3-diphenylquinoxaline; 2,4,5-triphenylimidazoyl dimer, 2-nitrofluorene, 2,4, 6-triphenylpyrilium tetrafluoroborate, 2,4,6-tris (trichloromethyl) -1,3,5-triazine, 3,3'-carbonylbiscoumarin, thiomihilerketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone, 2-benzyl-2-dimethylamino- 1- (4-morpholinophenyl) -butanone etc. are mentioned.

In addition, when forming the high refractive index hard coating layer 20 which concerns on this invention, an amine compound may coexist with a photoinitiator, in order to prevent the sensitivity fall by the oxygen inhibition of the said initiator. As such an amine compound, if it is nonvolatile, such as an aliphatic amine compound and an aromatic amine compound, it will not specifically limit, for example. For example, triethanolamine, methyl diethanolamine, etc. are suitable.

The components of the high refractive index hard coating layer 20 of the low reflection film according to the present invention include the above-described binder component and a photopolymerization initiator as essential components, and, if necessary, for example, a polymerization inhibitor, a curing catalyst, You may contain various additives, such as antioxidant, a dispersing agent, a leveling agent, and a silane coupling agent.

In the present invention, an organic metal compound such as a conductive polymer such as polypyrrole and polyaniline, a metal alcoholate, and a chelate compound may be further contained in the component of the high refractive index hard coating layer 20 for the purpose of imparting conductivity. In addition, for the purpose of improving the surface hardness of the components of the high refractive index hard coating layer 20, inorganic particles such as alkyl silicates and hydrolyzates thereof, colloidal silica, dry silica, wet silica, titanium oxide, colloidal phase, etc. The silica fine particles dispersed therein may be further contained.

Next, it is essential that the low refractive index layer 30 of the low reflection film according to the present invention is formed on the high refractive index hard coating layer 20 and contain a fluorine compound. The fluorine compound is preferably a fluorine compound crosslinked by heat or ionizing radiation. As a fluorine compound bridge | crosslinked, you may use the fluorine-containing copolymer which has an unsaturated group, the fluoropolymer which has a crosslinkable group, or the fluorine-containing monomer and the monomer for providing a crosslinkable group as a structural unit. In particular, the main chain is preferably composed of a fluorine-containing copolymer having a vinyl ether structure. The fluorine-containing copolymer preferably has a fluorine-containing olefin chain having a fluorine content of 30% by weight or more and a number average molecular weight in terms of polystyrene of 500 or more, preferably 5000 or more. Such a fluorine-containing copolymer is obtained by polymerizing a curable composition containing a fluorine-containing compound and a vinyl ether-containing compound, preferably a fluorine-containing olefin compound, a vinyl ether-containing compound copolymerizable with the fluorine-containing olefin compound, and necessity. It can obtain by polymerizing-reacting the curable composition which consists of reactive emulsifiers mix | blended accordingly. It is preferable to contain a reactive emulsifier as one component in the curable composition used in order to form a fluorine-containing copolymer. By using this reactive emulsifier component, the fluorine-containing copolymer contained in the coating liquid can be applied with good applicability and leveling property. As this reactive emulsifier, it is particularly preferable to use a nonionic reactive emulsifier.

Further, in the fluorine-containing copolymer constituting the low refractive index layer 30, the structural unit derived from the fluorine-containing olefin compound component is 20 to 70 mol%, preferably 25 to 65 mol%, more preferably 30 to 60 mol%. When the ratio of the structural unit derived from the fluorine-containing olefin compound component is less than 20 mol%, the fluorine content in the fluorine-containing copolymer obtained is likely to be excessive, so that the low refractive index layer 30 obtained does not have a sufficiently low refractive index. When the proportion of the structural unit derived from the fluorine-containing olefin compound component exceeds 70 mol%, the uniformity of the coating liquid is deteriorated, making it difficult to form a homogeneous coating film, and the transparency and adhesion to the substrate are not preferable, which is not preferable. . In the fluorine-containing copolymer, the structural unit derived from the vinyl ether structure-containing compound component is 10 to 70 mol%, preferably 15 to 65 mol%, more preferably 30 to 60 mol%. When the ratio of the structural units derived from the vinyl ether structure-containing compound component is less than 10 mol%, the uniformity of the coating liquid is deteriorated, making it difficult to form a homogeneous coating film, and the low refractive index layer 30 obtained when it exceeds 70 mol%. The transparency and low reflectance of the optical properties tend to be deteriorated, which is not preferable. As such a vinyl ether structure-containing compound component, by using a monomer containing a reactive functional group such as a hydroxyl group or an epoxy group, the strength of the cured film in the case of using the curable resin composition obtained as a coating agent is preferable. The ratio in the shear monomer of the monomer containing a hydroxyl group or an epoxy group is 0-20 mol%, Preferably it is 1-20 mol%, More preferably, it is 3-15 mol%. When this ratio exceeds 20 mol%, the optical characteristic of the obtained resin layer 30 tends to worsen, and a cured film tends to become weak. In the fluorine-containing copolymer containing a reactive emulsifier, the proportion of the structural unit derived from the reactive emulsifier component is usually 0 to 10 mol%, preferably 0.1 to 5 mol%. When this ratio exceeds 10 mol%, since the resin layer 130 obtained becomes sticky, handling becomes difficult, and since the moisture resistance of a coating agent falls, it is unpreferable.

In addition, the low refractive index layer 30 in the present invention is characterized in that it comprises 3 to 15 parts by weight of hollow silica with respect to 100 weight of the binder resin, the refractive index is increased when the content of the hollow silica particles is less than 3 parts by weight There is a disadvantage of increasing the reflectivity, and when the content of the hollow silica particles exceeds 15 parts by weight, there is a problem that the surface hardness due to the increase in the arithmetic mean roughness (Ra) value of the surface irregularities, that is, the reflectance increases, and the arithmetic of the surface irregularities This is because the surface hardness, the scratch resistance, the fingerprint removal function, and the cost due to the expensive hollow silica particles are increased due to the increase in the average roughness Ra.

Moreover, it is preferable to mix | blend a crosslinking | crosslinked compound with the low refractive index layer 30 which concerns on this invention other than a fluorine-containing copolymer, and it is effective because it gives predetermined curability and improves a hardening characteristic. As said crosslinkable compound, various amino compounds, pentaerythritol, polyphenol, glycol, alkyl silicates, various hydroxyl-containing compounds, such as its hydrolyzate, etc. are mentioned, for example. The amino compound used as the crosslinkable compound is a compound containing two or more of a total of any one or both of an amino group, for example, a hydroxyalkylamino group and an alkoxyalkylamino group, capable of reacting with a hydroxyl group or an epoxy group present in the fluorine compound, Specifically, a melamine type compound, a urea type compound, a benzoguanamine type compound, a glycoluril type compound, etc. are mentioned, for example. Melamine compounds are generally known as compounds having a skeleton in which a nitrogen atom is bonded to a triazine ring, and specific examples thereof include melamine, alkylated melamine, metyrolmelamine, alkoxylated methylmelamine, and the like. It is preferable to have two or more in any one or both of a tyrol group and an alkoxylated methyl group. Specifically, metharolized melamine, alkoxylated methylmelamine, or derivatives thereof obtained by reacting melamine and formaldehyde under basic conditions are preferable, in particular, good storage stability is obtained in the curable resin composition and good reactivity is obtained. Preferred is alkoxylated methylmelamine. There is no restriction | limiting in particular in the metharolized melamine and the alkoxylated methyl melamine used as a crosslinking | crosslinked compound, For example, various kinds obtained by the method described in the literature "Plastic material course [8] Yuri melamine resin" (Nigan Kogyo Shimbun) The use of resinous materials is also possible. Moreover, as a urea compound, the alkoxylated methyl urea which is a polymethyrrole urea derivative | guide_body, its metholurized uron which has a uron ring, the alkoxylated methyluron, etc. are mentioned besides urea. Moreover, also about compounds, such as a urea derivative, can use various resin-like thing described in the said document.

The usage-amount of such a crosslinking | crosslinked compound is 3-70 weight part with respect to 100 weight part of fluorine-containing copolymers, Preferably it is 3-50 weight part, More preferably, it is 5-30 weight part. If the amount of the crosslinkable compound is less than 3 parts by weight, the durability of the thin film formed by coating and curing may become insufficient. If it exceeds 70 parts by weight, it is difficult to avoid gelation in the reaction with the fluorine-containing copolymer. Moreover, a cured film may not become a thing of low refractive index, and a hardened | cured material may become weak.

In addition, it is preferable that the low refractive index layer 30 contains a fluororesin having silica fine particles, and / or a silane coupling agent, and / or an alkoxysilyl group in order to impart improved surface hardness, scratch resistance, and fingerprint removal function. .

The silica fine particles preferably contain dry silica, wet silica, silica fine particles dispersed in a colloidal phase, or the like, and particularly preferably contain silica fine particles dispersed in a colloidal phase. As for the particle size of the said silica fine particle, what has an average primary particle diameter (a spherical diameter: BET method) is 0.001-0.2 micrometer normally can be used, Preferably, the particle diameter of 0.001-0.005 micrometer is used. If the said average particle diameter is such a preferable range, transparency of a production film (resin layer) will not fall, and it will not become difficult to improve surface hardness. In addition, the shape of the said silica microparticle is spherical and the columnar phase is used preferably. In addition, the silica fine particles may be used two or more particles having different average particle diameters. In addition, the said silica fine particle can also be surface-treated and used. Surface treatment methods include physical surface treatments such as plasma discharge treatment and corona discharge treatment, and chemical surface treatment using a coupling agent, but chemical treatment is preferably used. As the coupling agent used for the chemical treatment, a silane coupling agent is particularly preferably used. It is preferable to make the component derived from a silica fine particle into 3 to 50%, 3 to 40%, especially 3 to 15% by solid content. If the component derived from silica microparticles | fine-particles is such a preferable range, the surface hardness and the scratch prevention property of the low refractive index layer 30 obtained are sufficient, and also the optical characteristics, such as transparency and a low reflectance, can also be made excellent.

The said silane coupling agent component is a compound represented by following General formula (1)-its hydrolysis product.

[Formula 1]

R (1) _a R (2) _b SiX _{4- (a + b)}

Wherein R (1) and R (2) are each a hydrocarbon group having an alkyl group, an alkenyl group, an allyl group, or a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group, a cyano group, or the like, and X is It is a hydrolyzable substituent selected from an alkoxyl group, an alkoxy alkoxyl group, and a halogen group to an acyloxy group. In addition, in Formula 1, a and b are each 0, 1 or 2 and (a + b) is 1, 2 or 3. It is preferable to make the component derived from a silane coupling agent into 5 to 70%, 15 to 65%, especially 20 to 60% by solid content. If the component derived from a silane coupling agent is such a preferable range, the surface hardness of the resin layer obtained will be enough, and it can also be made excellent in optical characteristics, such as transparency and a low reflectance.

The fluororesin having the alkoxysilyl group is a compound represented by the following formula (2) to a hydrolyzate product thereof.

[Formula 2]

R (3) _c R (4) _d SiX _{4- (c + d)}

Here, R (3) and R (4) are hydrocarbon groups each having a fluorine-substituted alkyl group, alkenyl group, allyl group, methacryloxy group, or (meth) acryloyl group. X is a hydrolyzable substituent selected from an alkoxyl group, an alkoxy alkoxyl group, a halogen group or an acyloxy group. In Formula 2, c and d are each 0, 1, 2 or 3 and (c + d) is 1, 2 or 3, respectively. It is preferable to make the component derived from the fluororesin which has an alkoxy silyl group into 20 to 90%, 25 to 80%, especially 30 to 70% by solid content ratio. If the component derived from the fluororesin which has an alkoxy silyl group is such a preferable range, the optical characteristic of transparency and low reflectance of the resin layer obtained is favorable, and the surface hardness of a resin layer can also be made good.

In addition, when forming the low refractive index layer 30 which concerns on this invention, in order to advance hardening of a coating liquid, you may use a curing catalyst. As a curing catalyst, it is preferable to accelerate the condensation reaction of a silane coupling agent, and an acid compound is mentioned as such. Of these, Lewis acid compounds are preferred. Examples of the Lewis acid compound include metal alkoxides and metal chelates such as acetacetoxy aluminum. Although the quantity of this hardening catalyst can be determined suitably, it is 0.1-10 weight part normally with respect to 100 weight part of silane coupling agents, for example.

In addition, when forming the low refractive index layer 30 which concerns on this invention, you may contain various additives, such as a polymerization inhibitor, antioxidant, a dispersing agent, a leveling agent, as needed.

In order for the low reflection film which concerns on this invention to become high transparency, it is preferable to make the haze of laminated | multilayer film less than 3.0%, Preferably it is less than 2.7%. If the haze is 3.0% or more, the transparency tends to be insufficient.

In addition, in order for the low refractive index layer 30 according to the present invention to have good surface hardness, scratch resistance, and fingerprint removal function, it is necessary to have fine irregularities on the surface of the low refractive index layer. The relationship between surface roughness, surface hardness and scratch prevention property due to the irregularities is considered to be due to the following mechanism. In other words, in the fine uneven surface, when the uneven surface is slid with steel wool or the like, the steel wool portion is slid in contact with only the convex portion, and when the steel wool or the like slides as the arithmetic mean roughness Ra increases. It is believed that the high convex portion that interferes increases the surface hardness and scratch resistance. As a result, the lower the surface arithmetic mean roughness (Ra) value, in particular, surface hardness and scratch resistance is improved. The range of the arithmetic mean roughness (Ra) value of the unevenness on the surface of the low refractive index layer 30 is 0.0001 μm to 0.025 μm. More preferably, they are 0.0001 micrometer-0.010 micrometer, More preferably, they are 0.0001 micrometer-0.005 micrometer. When the average arithmetic roughness Ra value of the unevenness exceeds this range, the haze of the low refractive index layer 30 is increased to lower the transparency. Moreover, when the arithmetic mean roughness Ra value of the said unevenness | corrugation is more than the said range, it will become difficult to improve surface hardness and a scratch prevention characteristic. In order to form fine irregularities on the surface of the low refractive index layer 30 in the present invention, inorganic particles such as colloidal silica, dry silica, wet silica, titanium oxide, glass beads, aluminum oxide, silicon carbide, silicon nitride, and colloidal phase It is preferable to contain silica fine particles dispersed in the above, and more preferably silica fine particles dispersed in a colloidal phase. Particularly preferably, fine irregularities can be formed by particles having an average particle diameter of the silica fine particles of 0.001 to 0.005 µm.

In addition, in order for the surface of the low refractive index layer 30 according to the present invention to become low reflectivity, the product of the refractive index and the thickness of the high refractive index hard coating layer 20 and the low refractive index layer 30 is the wavelength of the target light (usually visible light) wavelength. It is preferable to make it 1/4. Therefore, in the high refractive index hard coating layer 20 and the low refractive index layer 30, it is preferable that four times the product of the thickness of each layer and the refractive index n is in the range of 380-780 nm. That is, the relationship between the refractive index n and the thickness d in the high refractive index hard coating layer 20 and the low refractive index layer 30 is preferably a thickness within a range satisfying Equation 1 below.

[Equation 1]

n-d = λ / 4

(Here, λ is the wavelength range of visible light and is usually in the range of 380 nm ≦ λ ≦ 780 nm.)

In addition, in order to impart low reflectivity to the low reflective film according to the present invention, the thickness of the high refractive index hard coating layer 20 is preferably 1 to 50 µm, more preferably 2 to 30 µm. Moreover, the preferable thickness range of the said low refractive index layer 30 is 0.01-1.0 micrometer, More preferably, it is 0.05-0.12 micrometer. When the thicknesses of the high refractive index hard coating layer 20 and the low refractive index layer 30 are out of this range, the equation 1 cannot be satisfied, and the surface of the laminated film on the low refractive index layer 30 side does not become low reflective. .

In addition, in order for the surface of the laminated film on the low refractive index layer 30 according to the present invention to become low reflective, the refractive index of the low refractive index layer 30 is smaller than that of the high refractive index hard coating layer 20, that is, low It is preferable that the refractive index of the refractive layer 30 / the high refractive layer 20 is less than 1.0, More preferably, it is 0.6-0.95. In addition, the refractive index of the low refractive index layer 130 is preferably 1.47 or less, and more preferably 1.40 to 1.45. If the resin having a refractive index of less than 1.40 is formed, the increase in the content of fine particles in silica or the like causes a decrease in properties such as surface hardness and scratch resistance due to an increase in the surface arithmetic roughness average (Ra) value, and when the refractive index is higher than 1.47, the reflectance becomes high.

Next, the manufacturing method of the low reflection film excellent in the surface hardness, the scratch prevention property, and the fingerprint removal function which concerns on this invention is demonstrated.

In the low reflection film according to the present invention, the high refractive index hard coating layer 20 containing the (meth) acrylate compound and the low refractive index layer 30 containing the fluorine compound are sequentially disposed on at least one surface of the base film 10. It can manufacture by laminating | stacking. In the present invention, the high refractive index hard coating layer 20 and the low refractive index layer 30 preferably adjust the coating liquid in which each component is dispersed in a solvent, apply the coating liquid onto the base film, and then dry and It can form by hardening.

As the solvent used in the formation of the high refractive index hard coating layer 20 of the present invention, various known organic solvents can be used conventionally as long as the coating or printing workability of the composition of the present invention is improved and the binder component is dissolved. have. In particular, in the present invention, an organic solvent having a boiling point of 60 to 180 ° C. is preferable from the viewpoint of stability of the viscosity and dryness of the composition. Specific examples of such organic solvents include methanol, ethanol, isopropyl alcohol, n-butanol, tert-butanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, propylene glycol monomethyl ether, Cyclohexanone, butyl acetate, isopropyl acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetyl acetone, acetyl acetone, etc. are mentioned preferably. These may be used individually and may mix and use two or more types.

The amount of the organic solvent may be any compounding amount so as to be a composition having a viscosity in a state of good workability depending on the application means or printing means, but the solid content concentration of the composition is usually 60% by weight or less, preferably 50% by weight. It is suitable that it becomes below%. Usually, the method of adding a photoinitiator and dissolving it uniformly in the solution which melt | dissolved the binder component with the organic solvent is suitable.

In addition, when forming the low refractive index layer 30, the curable composition mainly consisting of a fluorine compound is methanol, ethanol, isopropyl alcohol, n-butanol, tert-butanol, ethylene glycol monomethyl ether, 1-methoxy- Applying a liquid dispersed in at least one solvent selected from 2-propanol, propylene glycol monomethyl ether, cyclohexanone, butyl acetate, isopropyl acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetyl acetone, acetyl acetone After that, it is preferable to take a method of drying and curing to form the low refractive index layer 30. The quantity of the solvent in this case can also be suitably changed according to the viscosity of the composition required, the thickness of the cured film made into the objective, drying temperature conditions, etc.

In addition, the laminated structure of the laminated film according to the present invention is a high refractive index hard coating layer 20 containing a (meth) acrylate compound on at least one surface of the base film 10, a low refractive index layer 30 containing a fluorine compound Is preferably formed. When the plurality of high refractive index hard coating layers 20 are formed on one surface side of the base film 10, the outermost surfaces on the same side of the base film 10 may be the low refractive index layer 30. It is preferable to form the low refractive index layer 30. Alternatively, a primer layer and a transparent conductive layer may be formed on the surface of the base film 10 on the side opposite to the high refractive index hard coating layer 20. Or you may provide a moisture proof layer and a protective layer on the surface of a resin layer. The thickness of the moisture proof layer and the protective layer is preferably 20 nm or less in order not to affect the antireflection function.

On the other hand, the display film using the low reflection film which concerns on this invention may form an adhesion layer or an adhesive layer on the low refractive index layer 30 of the said laminated | multilayer film, and may adhere a protective film to the adhesion layer or adhesion layer surface. The pressure-sensitive adhesive layer or adhesive layer is not particularly limited as long as the adhesive layer or adhesive layer is bonded by adhesion or adhesion.

As an adhesive or adhesive which forms the said adhesion layer or adhesive layer, a rubber type, a vinyl polymerization type, a condensation polymerization type, a thermosetting resin type, a silicone type, etc. can be used. Among them, butadiene-styrene copolymerization system (SBR), butadiene-acrylonitrile copolymerization system (NBR), chloroprene polymer system, isobutylene-isoprene copolymerization system (butyl rubber), etc. are mentioned as a rubber-based adhesive agent or adhesive agent. Can be. As an adhesive or adhesive agent of a vinyl polymerization system, an acrylic resin type, a styrene resin type, a vinyl acetate-ethylene copolymerization system, a vinyl chloride-vinyl acetate copolymerization system, etc. are mentioned. As an adhesive or adhesive agent of a condensation polymerization system, polyester resin system is mentioned. Examples of the thermosetting resin pressure sensitive adhesive include epoxy resins, urethane resins, formalin resins, and the like. These resins may be used alone or in combination of two or more thereof. In addition, an adhesive or an adhesive can use either a solvent type or a non-solvent type. Formation of an adhesion layer or an adhesive layer is performed using the technique currently performed, such as application | coating, using the above adhesive or adhesive agent. Moreover, you may contain a coloring agent in an adhesion layer or an adhesion layer. This is easily achieved by mixing and using a coloring agent containing pigment | dyes, such as a pigment and dye, to an adhesive or an adhesive agent. When it contains a coloring agent, it is preferable that the light transmittance in 550 nm is 40 to 80% of range as a laminated film. In addition, especially when used for plasma display, since the transmitted light is neutral gray or blue gray, and the color purity and contrast of the emission color of a display are required, it is achieved by using the adhesive layer or adhesive layer containing a pigment | dye. can do.

The resin material constituting the protective film is not particularly limited, and may be appropriately selected from resin materials used for known plastic base films. As the resin material for the protective film, for example, ester, ethylene, propylene, diacetate, triacetate, styrene, carbonate, methyl pentene, sulfone, ether ethyl ketone, nylon, acrylate, cycloaliphatic olefin, etc. And polymers or copolymers containing dogs as structural units. Among these resin materials, polymers or copolymerized polymers having one selected from ethylene such as polyethylene and polypropylene, esters such as propylene and polyethylene terephthalate as structural units are preferably used. In particular, the base film which consists of a polymer which makes an ester type a structural unit from the point of transparency and a mechanical characteristic is especially preferable.

In addition, the display filter using the low reflection film which concerns on this invention is a liquid crystal display device (LCD), a plasma display panel (PDP), a touch panel, and an electro luminescence through an adhesion layer or an adhesive layer on the said display film. It is obtained by adhering to the display surface of display surfaces, such as a display ELD, a cathode ray tube display apparatus, a portable digital assistant, and / or the surface of the front plate.

In addition, a liquid crystal display (LCD), a plasma display panel (PDP), a touch panel, an electro luminescence display (ELD), or a cathode ray tube display is provided through a pressure-sensitive adhesive layer or an adhesive layer on the display film using the low reflection film according to the present invention. A display can be obtained by adhering to the display surface of a display surface, such as an apparatus CRT and a portable digital assistant PDA.

The means for closely contacting the laminated film produced as described above with the surface of the display display surface and / or its front plate is not particularly limited. For example, an adhesive layer or an adhesive layer is applied to the display display member or the base film 10. It is made of a laminated film by drying, bonding the low refractive index layer 30 of the low reflection film to a surface layer by a pressing roller or the like, and adhering the display display member and the base film 10 through an adhesive layer or an adhesive layer. A display filter or display can be obtained.

Hereinafter, an Example and a comparative example are given and this invention is demonstrated further more concretely.

Example 1

Formation of High Refractive Index Hard Coating Layer 20

Photoinitiator (solid content 100%) in a mixture obtained by dissolving acrylate-containing high refractive index hard coating resin (solid content 100%) (product of Nippon Synthetic Chemicals, UV-9100B) in isopropyl alcohol (IPA) (Ciba Specialty Chemicals product) , IRGACURE-184) was added (oligomer: IPA: photoinitiator = 48.8 wt%: 48.8 wt%: 2.4 wt%) and then uniformly mixed to form a solution of a high refractive index hard coating layer material. At this time, the photoinitiator of the solution contained 0.05 times compared to the hard coating resin component. The uniformly mixed solution was applied onto the surface of the base film 10 made of a polyester film (Toray Co., Ltd., Lumirror) having a thickness of 100 μm using a microgravure coater, dried at 80 ° C. for 5 minutes, and then UV 0.5 J / cm <^2> was irradiated, the coating layer was hardened | cured, and the high refractive index hard coating layer 20 which has a thickness of about 2.0 micrometers and fine unevenness | corrugation, and whose arithmetic mean roughness Ra of the unevenness | corrugation is 0.003 micrometers was formed.

Formation of Low Refractive Index Layer 30

Dissolve paint (solid content 10%) (JSR Co., Ltd., TU2263, 5 parts by weight of hollow silica with respect to 100 weight of binder resin) containing fluorine-containing copolymer (fluoroolefin / vinyl ether copolymer) in isopropyl alcohol (fluorine-based Copolymer: Isopropyl alcohol = 8.2wt%: 91.8wt%) and the coating liquid obtained by stirring this mixture was applied on the high refractive index hard coating layer 20 using a microgravure coater at a thickness of about 112-116 nm, and 80 After drying at 5 ° C. for 5 minutes, ultraviolet rays were irradiated with 0.5 J / cm ² to cure the coating layer, having a thickness of about 0.1 μm, fine irregularities, and a low refractive index layer 30 having an arithmetic mean roughness Ra of 0.003 μm. Formed).

[Example 2]

Formation of High Refractive Index Hard Coating Layer 20

Photoinitiator (solid content 100%) (Ciba Specialty Chemicals, IRGACURE-184) in a mixture obtained by dissolving acrylate-containing hard coating resin (100% solids) (UV-9100B, manufactured by Nippon Synthetic Chemicals Co., Ltd.) in isopropyl alcohol. ) Was added (oligomer: IPA: photoinitiator = 48.8 wt%: 48.8 wt%: 2.4 wt%) and then uniformly mixed to form a solution of a high refractive index hard coating layer material. At this time, the photoinitiator of the solution contained 0.05 times compared to the hard coating resin component. The uniformly mixed solution was applied onto the surface of the base film 10 made of a polyester film (Toray Co., Ltd., Lumirror) having a thickness of 100 μm using a microgravure coater, dried at 80 ° C. for 5 minutes, and then UV 0.5 J / cm <^2> was irradiated, the coating layer was hardened | cured, and the high refractive index hard coating layer 20 which has a thickness of about 2.0 micrometers and fine unevenness | corrugation, and whose arithmetic mean roughness Ra of the unevenness | corrugation is 0.003 micrometers was formed.

Formation of Low Refractive Index Layer 30

Dissolve the paint (solid content 10%) containing the fluorine-containing copolymer (fluoroolefin / vinyl ether copolymer) (JSR Co., Ltd., TU2207, 10 parts by weight of hollow silica with respect to 100 weight of the binder resin) in isopropyl alcohol (fluorine-based Copolymer: Isopropyl alcohol = 8.2wt%: 91.8wt%) and the coating liquid obtained by stirring this mixture was applied on the high refractive index hard coating layer 20 using a microgravure coater at a thickness of about 112-116 nm, and 80 After drying at 5 ° C. for 5 minutes, ultraviolet rays were irradiated with 0.5 J / cm ² to cure the coating layer. The low refractive index layer 30 having a thickness of about 0.1 μm and fine irregularities and having an arithmetic mean roughness Ra of the irregularities was 0.005 μm. Formed).

Comparative Example 1

High refractive index  Formation of Hard Coating Layer 20

Paint containing solid coating resin and photopolymerization initiator (50% solids) (JSR Co., KZ7528) 11.1% by weight, solution containing tin oxide-containing indium oxide particles (ATO) with an average particle diameter of 20-40 nm dispersed in Isopropanol (Solid 25%) (Sigma-ALDRICH, 50926-11-9) 88.9 wt% was uniformly mixed to form a solution of the high refractive index hard coating layer material. At this time, the indium oxide particles (ATO) of the solution contained 1 times compared to the hard coating resin component. The uniformly mixed solution was applied on the surface of the base film 10 made of a polyester film (Toray Co., Ltd., Lumirror) having a thickness of 100 μm using a microgravure coater, dried at 80 ° C. for 5 minutes, and then subjected to ultraviolet ray 1.0. J / cm <^2> was irradiated, the coating layer was hardened | cured, and the high refractive index hard coating layer 20 which has a thickness of about 2.0 micrometers and fine unevenness | corrugation, and whose arithmetic mean roughness Ra of the unevenness | corrugation is 0.015 micrometers was formed.

Formation of Low Refractive Index Layer 30

Dissolve paint (solid content 10%) (JSR Co., Ltd., TU2263, 5 parts by weight of hollow silica with respect to 100 weight of binder resin) containing fluorine-containing copolymer (fluoroolefin / vinyl ether copolymer) in isopropyl alcohol (fluorine-based Copolymer: Isopropyl alcohol = 8.2wt%: 91.8wt%) and the coating liquid obtained by stirring this mixture was applied on the high refractive index hard coating layer 20 using a microgravure coater at a thickness of about 112-116 nm, and 80 After drying at 5 ° C. for 5 minutes, ultraviolet rays were irradiated with 0.5 J / cm ² to cure the coating layer. The low refractive index layer 30 having a thickness of about 0.1 μm and fine irregularities and having an arithmetic mean roughness Ra of the irregularities was 0.015 μm. Formed).

Comparative Example 2

Formation of High Refractive Index Hard Coating Layer 20

Paint containing solid coating resin and photopolymerization initiator (50% solids) (JSR Co., KZ7528) 11.1% by weight, solution containing tin-containing indium oxide particles (ATO) with an average particle diameter of 20-40 nm dispersed in Isopropanol ( Solid content 25%) (from SIGMA-ALDRICH, 50926-11-9) 88.9 wt% was uniformly mixed to form a solution of high refractive index hard coating layer material. At this time, the indium oxide particles (ATO) of the solution contained twice as much as the hard coating resin component. The uniformly mixed solution was applied on the surface of the base film 10 made of a polyester film (Toray Co., Ltd., Lumirror) having a thickness of 100 μm using a microgravure coater, dried at 80 ° C. for 5 minutes, and then subjected to ultraviolet ray 1.0. J / cm <^2> was irradiated, the coating layer was hardened | cured, and the high refractive index hard coating layer 20 which has a thickness of about 2.0 micrometers and fine unevenness | corrugation, and whose arithmetic mean roughness Ra of the unevenness | corrugation is 0.025 micrometers was formed.

Formation of Low Refractive Index Layer 30

Dissolve the paint (solid content 10%) containing fluorine-containing copolymer (fluoroolefin / vinyl ether copolymer) (JSR Co., Ltd., TU2189, 40 parts by weight of hollow silica with respect to 100 weight of binder resin) in isopropyl alcohol (fluorine-based Copolymer: Isopropyl alcohol = 8.2wt%: 91.8wt%) and the coating liquid obtained by stirring this mixture was applied on the high refractive index hard coating layer 20 using a microgravure coater at a thickness of about 112-116 nm, and 80 After drying at 5 ° C. for 5 minutes, ultraviolet rays were irradiated with 0.5 J / cm ² to cure the coating layer, having a thickness of about 0.1 μm, fine irregularities, and a low refractive index layer 30 having an arithmetic mean roughness Ra of the irregularities of 0.037 μm. Formed).

Next, a method of evaluating the characteristics using the low reflection film prepared in the above Examples and Comparative Examples will be described.

Experimental Example 1 Measurement of Transmittance

This experiment was carried out using a direct reading haze computer manufactured by Sugashi Kenki.

Experimental Example 2: Measurement of Reflectance

The spectrophotometer U-3410 from Hitachi Keisoku was used. The sample film was scratched evenly on the back surface with 320-400 waterproof sandpaper, and black paint was applied to completely remove the reflection from the back surface. . In addition, a reflectance here shows the minimum value in wavelength range 380nm <=== 780nm.

Experimental Example 3: Evaluation of Surface Hardness (Pencil Hardness)

It measured according to JIS K-5400 using HEIDON (manufactured by Shinkokagaku Co., Ltd.).

[Experimental Example 4: scratch resistance (steel wool hardness) evaluation]

Using the steel wool of # 0000, the number of wounds when reciprocating 10 times under a load of 250 gf / cm 2 was observed. According to the level of the wound, the hardness was classified into the following five levels (level 5: no wound, level 4: 1-5 wounds, level 3: 5-10 wounds, level 2: 10 or more wounds, level) 1: wound on the entire surface).

Experimental Example 5: Fingerprint Removal Characteristic Evaluation

Fingerprint removal characteristics of all samples were treated with matte black ink on the back of the low reflective film, and the finger was slowly pressed against the surface of the low reflective film. Judging accordingly. "○" indicates that there is no visible fingerprint, "△" indicates that the fingerprint remains weak and "X" indicates that the fingerprint is well seen, respectively.

The results of the experiment evaluating the characteristics are shown in Table 1 below.

TABLE 1

Transmittance (%) Reflectance
(%) Surface hardness
(H) Anti-scratch
(Steel wool hardness) Fingerprint Removal Characteristics Example 1 91.8 1.5 3 5 ○ Example 2 91.4 0.8 3 5 ○ Comparative Example 1 89.1 1.3 2 2 △ Comparative Example 2 87.9 0.3 2 ~ 1 One X

The high refractive index hard coating layer of the low reflection film according to Examples 1 and 2 is made of a hard coating resin containing acrylate and has arithmetic mean roughness (Ra) of 0.003 μm after curing, and according to Comparative Examples 1 and 2 The high refractive index hard coating layer of the reflective film contains indium oxide particles (ATO) 1 and 2 times higher than the paint containing the hard coating resin and the photopolymerization initiator and the hard coating coating resin, respectively. 0.015 micrometer and 0.025 micrometer, respectively.

In addition, the low refractive index layer of the low-reflective film in the improved paint has arithmetic mean roughness Ra of 0.003 μm and 0.005 μm, respectively. In this case, surface hardness is lowered, scratch resistance is lowered, and fingerprint removal characteristics are lowered. In addition, when the arithmetic mean roughness (Ra) value is further increased to 0.037 μm as in Comparative Example 2, the refractive index is increased due to the increase in the content of indium oxide particles (ATO) in the high refractive index hard coating layer and the refractive index is increased in the hollow silica content of the low refractive index layer. Although the reflectance can be considerably lowered due to the drop, the application as a display element due to the rapid decrease in transmittance is limited, and the quality is deteriorated due to the loss of fingerprint removal characteristics.

As can be seen in Table 1, in the low reflection film according to the embodiment of the present invention, the high refractive index hard coating layer and the low refractive index layer of which the refractive index of the hard coating layer is adjusted to the high refractive index on the base film are sequentially stacked in a two-layer structure. However, the high refractive index hard coating layer and the low refractive index layer has a fine unevenness, by controlling the arithmetic mean roughness (Ra) of the unevenness, it can be seen that the surface hardness and scratch resistance and fingerprint removal characteristics are superior to the comparative example. .

Therefore, the low reflection film according to the present invention improves physical properties and does not contain expensive indium oxide particles (ATO) as compared to a low reflection film having a conventional multilayer structure, thereby improving productivity and reducing manufacturing costs. Therefore, it is possible to provide an improved low reflection film for display, which is suitable as a low reflection high hardness film applied to, for example, a large flat screen front surface such as a plasma display, a liquid crystal television front surface, or a small mobile display using a touch screen. .

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

1 is a cross-sectional view of a low reflection film according to an embodiment of the present invention.

2 is a cross-sectional view of a low-reflection film of a three-layer structure composed of a conventional hard coating layer, a high refractive index layer and a low refractive index layer.

3 is a cross-sectional view of a low-reflection film of a four-layer structure composed of a conventional hard coating layer, an intermediate refractive index layer, a high refractive index layer and a low refractive index layer.

4 is a cross-sectional view of a five-layer low reflection film composed of a conventional hard coating layer, a high refractive index layer, a low refractive index layer, a high refractive index layer and a low refractive index layer.

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

10: base film 20: high refractive index hard coating layer

30: low refractive index layer 100: base film

105: hard coating layer 110: intermediate refractive index layer

120: high refractive index layer 130: low refractive index layer

Claims (11)

In the low reflection film, The high refractive index hard coating layer 20 and the low refractive index layer 30 are sequentially stacked on at least one surface of the base film 10, and the surface of the low refractive index layer 30 has fine irregularities and arithmetic of the irregularities. Average roughness Ra is 0.0001 micrometer-0.005 micrometer, The low reflection film characterized by the above-mentioned. The method of claim 1, The low refractive index layer 30, characterized in that it comprises 3 to 15 parts by weight of hollow silica relative to 100 weight of the binder resin, low reflection film. The method of claim 1, The low reflection film, haze is characterized in that less than 3%, low reflection film. The method of claim 1, The low reflection film is characterized in that the surface hardness of 3H or more, low reflection film. The method of claim 1, The low reflection film is a low reflection film, characterized in that the water contact angle is more than 80 °. The method of claim 1, The high refractive index hard coating layer 20 is 1 ~ 50㎛ thickness, the low refractive index layer 30, characterized in that the thickness of 0.01 ~ 1.0㎛, low reflection film. The method of claim 1, The low refractive index layer 30, characterized in that it comprises a fluorine-containing copolymer having a vinyl ether structure in the main chain, low reflection film. The method of claim 7, wherein The low reflection film (30) further comprises silica fine particles having a particle size of 0.001 µm to 0.2 µm. The method according to any one of claims 1 to 8, The low refractive layer 30 contains a silane coupling agent represented by the following formula (1) or a hydrolyzate thereof or a reactant thereof, [Formula 1] R (1) _a R (2) _b SiX _{4- (a + b)} Here, R (1) and R (2) are each an alkyl group, an alkenyl group, an allyl group, or a hydrocarbon group having a halogen group, an epoxy group, an amino group, a mercapto group, a methacryloxy group to a cyano group, and X is an alkoxyl group , Alkoxyalkoxy group, a hydrolyzable substituent selected from halogen to acyloxy group, a and b are each 0, 1 or 2, and (a + b) is 1, 2 or 3, characterized in that Reflective film. 10. The method of claim 9, The low refractive layer 30 further contains a fluorine resin or a hydrolysis product thereof having an alkoxysilyl group represented by the following Chemical Formula 2 as a fluorine compound, [Formula 2] R (3) _c R (4) _d SiX _{4- (c + d)} Wherein R (3) and R (4) are each a hydrocarbon group having a fluorine-substituted alkyl group, alkenyl group, allyl group, methacryloxy group, or (meth) acryloyl group, and X is an alkoxyl group or an alkoxyalkoxy group , A hydrolyzable substituent selected from a halogen group or an acyloxy group, c and d are each 0, 1, 2 or 3, and (c + d) is 1, 2 or 3, characterized in that the low reflection film . The method according to any one of claims 1 to 8, The low reflection film is a low reflection film, characterized in that the increase in reflectance is less than 0.5% before and after light irradiation for 500 hours.

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