KR20140036771A

KR20140036771A - Optical laminate, polarizing plate and image display using the same

Info

Publication number: KR20140036771A
Application number: KR1020120103298A
Authority: KR
Inventors: 안종남; 김윤봉; 조영민; 조용균
Original assignee: 에스케이이노베이션 주식회사
Priority date: 2012-09-18
Filing date: 2012-09-18
Publication date: 2014-03-26

Abstract

The present invention relates to an optical laminated body, a polarizing plate and a display device including the same, and more particularly, to an optical laminated body having an improved anti-glare property and contrast by forming an anti-glare layer having an uneven portion, and a polarizing plate and a display device including the same.

Description

Optical laminated body and polarizing plate and display device including the same {OPTICAL LAMINATE, POLARIZING PLATE AND IMAGE DISPLAY USING THE SAME}

In recent flat panel displays such as liquid crystal displays, plasma displays or organic EL displays, there is a problem that outdoor sunlight or indoor light is reflected on the display surface and the original image can not be seen properly. Therefore, the most efficient method Is to minimize the reflection of various external light generated on the display surface.

In order to reduce the reflection of external light, it is mainly used to remove the light through extinction interference phenomenon and to remove it through diffuse reflection of light. The method of reducing the external light by the extinction interference phenomenon of light is a method of reducing the refractive index And alternately stacking thin films having a high refractive index to prevent reflection of light. However, this method has problems in refractive index and adhesiveness between thin films, and has a problem of high process cost due to process complexity.

As a method of removing external light through diffuse reflection of light, external light is diffused through a method of forming irregularities. As a method of forming the unevenness, there is a method of forming the unevenness by giving an embossing effect on the surface and a method of forming the unevenness by using a filler. The method of using embossing has a disadvantage in that it is expensive to manufacture an embossing roll, and thus has a limitation to be applied to production.

In recent years, concave-convex shapes are made finer with the demand for higher resolution of panel resolution. However, the unevenness of the uneven shape may meet the demand for high resolution of the panel resolution, but there are problems such as whitening of the image display surface (whitening) and low contrast with respect to reflected light of external light on the display surface. Is being reported.

In addition, when forming the unevenness, it becomes possible to exhibit sufficient optical characteristics to some extent, but when the transmitted light from the backlight backside inside the display passes through the uneven surface formed on the outermost surface of the panel, the uneven shape serves as a fine lens. As a result, a state of 'flashing' may occur that disturbs the displayed pixel or the like.

Therefore, as a method of eliminating the 'flashing' caused by the high resolution of the panel resolution, by increasing the surface irregularities for the purpose of increasing the sharpness, by adding scattering particles having a refractive index difference and the resin forming the antiglare layer The method of imparting the scattering effect in the antiglare layer was used. However, although a good solution has been made for any means of 'flashing', there is a problem that the overall image visibility is deteriorated. The whitening of the surface or the whitening (milk whitening) due to the internal scattering effect caused by the formation of the unevenness are considered to be the main factors to lower the contrast, and the anti-glare and the contrast enhancement are both related to the trade-off. There remains a technical difficulty to satisfy. For example, black reproducibility in screen display is poor. In other words, it is difficult to recognize black gradation expression in bright room, especially gradation difference of black in low gradation, and the sensitivity is lowered.

U.S. Patent No. 5387463 (Patent Document 1) describes an example of applying an anti-glare function by applying silica particles having a refractive index similar to that of a hard coating layer, but when using silica particles having a non-uniform shape, The reflection occurs, the glare due to the irregular reflection, or when the size of the particles increases, the transmittance is lowered and the haze increases.

In addition, U.S. Patent Publication No. 2009-0061114 (Patent Document 2) discloses an anti-reflection film that realizes an anti-glare function by applying a low refractive layer including a hard coating layer and hollow silica, but on the low refractive layer which is the outermost layer. Due to the presence of hollow silica, turbidity is severe and wear resistance is weak.

Therefore, development of an optical laminated body which can attain anti-glare property and black reproducibility and can effectively prevent glare of the image surface is desired, and not only a liquid crystal display (LCD) but also a cathode ray tube display device (CRT). ), An optical laminated body that can be used for other purposes such as a plasma display (PDP), a fluorescent display tube, and a field emission display is urgently needed.

U.S. Patent # 5387463 United States Patent Application Publication No. 2009-0061114

An object of the present invention is to provide an optical laminated body having excellent anti-glare property and black reproducibility and excellent anti-glare property by forming an aggregate having a predetermined size in the anti-glare layer.

In addition, an object of the present invention is to provide a polarizing plate including an optical laminate on one or both surfaces of the polarizing film.

In addition, another object of the present invention is to provide a display device including the above-described optical laminated body or polarizing plate.

The present inventors to solve the above problems of the prior art, a transparent base film; And an antiglare layer provided on the transparent base film and having an uneven portion, wherein the uneven portion is an aggregate that satisfies the following Formula 1 and Formula 2 in which 1 to 1000 fine particles having an average particle diameter of 1 to 100 nm are aggregated. Formed by (P),

1 µm ≤ P _a ≤ 100 µm [Equation 1]

1.0 <P _max / P _min ≤ 50 [Equation 2]

The arithmetic mean surface roughness Ra of the antiglare layer having the uneven portion is 0.01 to 0.1 μm, and the optical laminated body satisfies Equations 3 and 4 below.

0.1% ≤ H _t ≤ 2.0% [Equation 3]

0 <H _t -H _o ≤ 0.5 [Equation 4]

(A in the formula 1 and the formula 2 P _a is an average agglomerated light, P _max is the diameter of the maximum aggregation (㎛), P _min is a minimum aggregate diameter (㎛) of the aggregates, H _t is from Equation 3 and Equation 4 Total haze value (%), H _o represents external haze value (%).)

A low refractive index layer is further included on the antiglare layer, and the following Equations 5 and 6 may be satisfied.

1.20 ≤ R _Low ≤ 1.49 [Equation 5]

1 <R _AG / R _Low ≤ 1.8 [Equation 6]

(In Formulas 5 and 6, R _AG is the refractive index of the antiglare layer, and R _Low is the refractive index of the low refractive layer.)

The antiglare layer may include a compound represented by Formula 1 below.

[Formula 1]

(In Formula 1, R1 may be selected from polyester, ethylene oxide or propylene oxide addition polyether, (C6-C20) aralkyl, the terminal of the polyester, polyether and aralkyl is an acrylic group, carboxyl group or May be further substituted with a hydroxy group, R 2 may be alkyl of (C 1 -C 20) or cycloalkyl of (C 3 -C 20), and x and y are each independently 1 to 10.)

The antiglare layer is formed from a composition for forming an antiglare layer including the aggregate and the resin, and the content of the fine particles is contained in an amount of 0.01 to 2 parts by weight based on 100 parts by weight of the total antiglare layer forming composition, and the resin is ionizing radiation curable. It can be 1 type chosen from resin, a solvent drying type resin, and a thermosetting resin.

The anti-glare layer forming composition further comprises a modified silicone-based leveling agent, the content of the leveling agent may comprise 0.01 to 1 parts by weight based on 100 parts by weight of the total anti-glare layer forming composition.

The antiglare layer may have a thickness of 1 to 30 μm, and the low refractive layer may have a thickness of 0.01 to 0.5 μm.

The present invention can provide a polarizing plate including the optical laminate on one side or both sides of the polarizing film.

In addition, a display device including the optical laminate or the polarizing plate may be provided, and the display device may include a liquid crystal display (LCD) and a plasma selected from a TN type, a STN type, an OCB type, a HAN type, a VA type, and an IPS type. It can be selected from a display, a field emission display, an organic EL display, an inorganic EL display, or an electronic paper.

The optical laminated body according to the present invention forms an aggregate having a constant size inside the antiglare layer to provide anti-glare property and at the same time provide excellent contrast, thereby improving black reproducibility and significantly improving the anti-glare effect.

In addition, the optical laminated body according to the present invention can be effectively applied to the surface of various display devices such as CRT, liquid crystal display, plasma display, organic EL display and the like.

1 shows a surface micrograph of an optical laminate according to an embodiment of the present invention.

The present invention relates to an optical laminated body that provides anti-glare properties and at the same time provides excellent contrast, excellent black reproducibility, and remarkably improved anti-glare effect.

The first aspect of the optical laminated body of the present invention may be formed including an antiglare layer provided on the transparent base film and the transparent base film and having an uneven portion.

In addition, the second aspect of the present invention may be formed by further comprising a low refractive layer on top of the optical stack of the first aspect.

The first aspect and the second aspect are intended to illustrate embodiments of the present invention and are not limited thereto.

Hereinafter, the optical laminated body of this invention is demonstrated more concretely.

The transparent base film may be used without limitation as long as it is a plastic film having transparency, and specific examples include cycloolefin derivatives having units of monomers containing cycloolefin, such as norbornene or polycyclic norbornene monomers; Cellulose, i.e., diacetyl cellulose, triacetyl cellulose, acetyl cellulose butyrate, isobutyl ester cellulose, ethylene-vinyl acetate copolymer, propionyl cellulose, butyryl cellulose, acetylpropionyl cellulose; Or polyolefins such as polycycloolefin, polyester, polystyrene, polyamide, polyetherimide, polyacryl, polyimide, polyethersulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl A thermoplastic polymer such as an alcohol, a polyvinyl acetal, a polyether ketone, a polyether ether ketone, a polyether sulfone, a polymethyl methacrylate, a polyethylene terephthalate, a polycarbonate, a polybutylene terephthalate, a polyethylene naphthalate, a polyurethane, ; &Lt; / RTI >

In addition, unstretched, uniaxially or biaxially stretched films can be used depending on whether or not the film is stretched. Preferably, it is a uniaxial or biaxially stretched polyester film, a polymethyl methacrylate film, or a polycycloolefin-based film superior in transparency and heat resistance, more preferably excellent in transparency and optically anisotropic A film made of triacetyl cellulose or isobutyl ester cellulose, or the like can be suitably used.

The thickness of the transparent base film is preferably 8 to 1,000 mu m, more preferably 40 to 100 mu m. If the thickness is less than 8 μm and the strength is lowered, the workability is inferior. If the thickness is more than 1,000 μm, the thickness becomes too thick to reduce the transparency, or the weight of the polarizing plate or the display device may increase.

The antiglare layer is provided on the transparent base film and is provided with an uneven portion. It is preferable that the uneven part is formed from the aggregate (P) which satisfies the following formula 1 and formula 2 in which 1 to 1000 fine particles having an average particle diameter of 1 to 100 nm are aggregated.

1 µm ≤ P _a ≤ 100 µm [Equation 1]

1.0 <P _max / P _min ≤ 50 [Equation 2]

(In Formula 1 and Formula 2, P _a is the average aggregate diameter of the aggregate, P _max is the diameter of the maximum aggregate (μm), P _min is the diameter of the minimum aggregate (μm).)

If the average aggregate diameter of the aggregate is less than 1 ㎛ difficult to implement anti-glare performance, if it is more than 100 ㎛ may have a high haze problem difficult to implement black reproducibility, the average aggregate diameter of the aggregate is 1 to 100 ㎛ It can effectively improve the anti-glare property, and can realize excellent black reproducibility and anti-glare property.

In addition, it is possible to form the unevenness that can achieve more effective anti-glare characteristics when the ratio of the diameter of the maximum aggregate and the diameter of the minimum aggregate is 1.0 to 50 while satisfying the size of the average aggregate diameter of the aggregate. When the ratio of the diameter of the largest aggregate and the diameter of the minimum aggregate is less than 1.0, the haze is high, so that it is difficult to implement black reproducibility, and when the ratio exceeds 50, the problem of preventing glare may occur.

The uneven portion formed of the above-mentioned aggregate may be represented by an arithmetic mean surface roughness (Ra), preferably the arithmetic mean surface roughness (Ra) is 0.01 to 0.1 ㎛ may exhibit excellent black reproducibility, anti-glare property and surface uniformity. It is effective.

If the arithmetic mean surface roughness (Ra) is less than 0.01㎛ it is difficult to implement the anti-glare performance, if it exceeds 0.1㎛ may cause a problem that the black reproducibility is reduced due to the increase in the external haze.

It is preferable that the anti-glare layer mentioned above is formed from the composition for anti-glare layer formation containing an aggregate and resin.

The aggregate is formed by aggregation of 1 to 1,000 fine particles having an average particle diameter of 1 to 100 nm as described above, and the fine particles are preferably silica particles.

Silica particles may be spherical or amorphous, and it is more effective to use spherical to improve the dispersibility of the particles. The average particle diameter of a silica particle is 1-100 nm, and what disperse | distributed to the solvent can be used. The silica particles having an average particle diameter of 1 to 100 nm may be those surface-treated with a silane coupling agent, and in this case, they are effective because they improve dispersibility with a solvent.

The silane coupling agent is specifically methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldie Methoxysilane, isobutyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, 3,3,3-trifluoropropyltrimethoxysilane, methyl -3,3,3-trifluoropropyldimethoxysilane, γ- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxymethyltrimethoxysilane, γ-glycidoxymethyltri Ethoxysilane, γ-glycidoxyethyltrimethoxysilane, γ-glycidoxyethyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ- (β-glycidoxymethoxy) propyltrimethoxysilane, γ- (meth) acrylooxymethyltrimethoxysil , γ- (meth) acrylooxymethyltriethoxysilane, γ- (meth) acryloxyethyltrimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, γ- (meth) acrylo Oxypropyltrimethoxysilane, γ- (meth) acrylooxypropyltrimethoxysilane, γ- (meth) acryloxyoxytriethoxysilane, butyltrimethoxysilane, isobutyltriethoxysilane, hexyltrie Oxysilaoctyltriethoxysilane, decyltriethoxysilane, butyltriethoxysilane, isobutyltriethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, 3-ureidoisopropylpropyltriethoxysilane, Perfluorooctylethyltrimethoxysilane, perfluorooctylethyltriethoxysilane, perfluorooctylethyltriisopropoxysilane, tripleuropropyltrimethoxysilane, N-β (aminoethyl) γ-amino Propylmethyldimethoxysilane, N-β (aminoethyl) γ-ami At least one selected from the group consisting of nopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, trimethylsilanol, and methyltrichlorosilane can be used. . The solvent in which the silica particles are dispersed may be an alcohol; for example, methanol, ethanol, isopropanol, butanol and octanol, ethylcellulose, methylcellulose; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; Esters such as ethyl acetate, butyl acetate, ethyl lactate and γ-butyrolactone; Ethers such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether, diethylene glycol monobutyl ether; Aromatic hydrocarbons such as benzene, toluene and xylene; And amides such as dimethylformamide, dimethyl acetamide and N-methylpyrrolidone.

More preferably, silica particles having an average particle diameter of 1 to 100 nm are treated with tetramethoxysilane or γ- (meth) acrylooxypropyltrimethoxysilane to modify hydrophilic hydroxy groups to hydrophobic in terms of stability to solvents. desirable.

As for the average particle diameter of the said silica particle, 1-100 nm is preferable, More preferably, it is effective that it is 5-50 nm. If the average diameter of the silica particles is less than 1 nm, the size of the aggregate is small, so that it is difficult to express a sufficient light diffusing effect, and if the average diameter of the silica particles is more than 100 nm, the formation of the aggregate becomes large, and the black reproducibility may be lowered due to the increase in external haze.

The content of the fine particles is preferably contained in an amount of 0.01 to 2 parts by weight based on 100 parts by weight of the total antiglare layer-forming composition. When the fine particles are less than 0.01 parts by weight, it is difficult to implement a light diffusion effect, and when the fine particles are more than 2 parts by weight, haze may increase due to excessive formation of aggregates.

In addition, the antiglare layer-forming composition may further include a modified silicone leveling agent. The modified silicone leveling agent can reduce the compatibility of the silica particles to control the size of the aggregates, and has a defoaming property, which significantly reduces bubbles in the antiglare layer forming composition, thereby forming a uniform antiglare layer. .

The modified silicon-based leveling agent according to an embodiment of the present invention is preferably the following formula (1).

[Formula 1]

More preferred modified silicone-based leveling agents in formula (1), wherein R1 is ethylene oxide or propylene oxide addition polyether, and R2 is an alkyl of (C1-C10) having an ether structure of intramolecular hydrophilicity, so as to have a hydrophobic group on the surface of silica fine particles. The interaction is effective because it allows uniform formation of aggregates of the desired size.

The content of the modified silicone leveling agent is preferably included 0.01 to 1 parts by weight based on 100 parts by weight of the total composition for forming an antiglare layer. If the leveling agent is less than 0.01 part by weight, the particle size does not participate in aggregation, and when the leveling agent is more than 1 part by weight, the size of the aggregate becomes large and a problem of raising the haze of the optical stack may occur.

In the composition for forming an antiglare layer, the resin is a curable resin, and preferably a curable resin that provides transparency. The curable resin may be at least one selected from the group consisting of a solvent-drying resin and a thermosetting resin which are formed by only drying the solvent in the application process of an ionizing radiation curable resin or a thermoplastic resin, which is a resin cured by ultraviolet rays or electron beams. have. Preferably, it may be an ionizing radiation curable resin, and more preferably, the use of a mixture of ionizing radiation curable resins and thermosetting resins is very effective for improving mechanical properties such as improving hardness and scratch resistance of the optical laminate.

Specific examples of the ionizing radiation curable resins are compounds having radical polymerizable functional groups such as (meth) acrylate groups, and more specific examples thereof include oligomers, prepolymers or monomers of (meth) acrylates.

Specific examples of the (meth) acrylate-based oligomer and prepolymer include low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, and polythiolpolyene resins. And oligomers or prepolymers composed of (meth) acrylic acid esters of polyfunctional compounds such as polyhydric alcohols.

As a specific example of a (meth) acrylate type monomer, ethyl (meth) acrylate, ethylhexyl (meth) acrylate, trimethylol propane tri (meth) acrylate, hexanediol (meth) acrylate, and tripropylene glycol di (meth) ) Acrylic acid, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 6- hexanediol di (meth) acrylate, neopentyl glycol di (Meth) acrylate etc. are mentioned, The said (meth) acrylate means an acrylate or methacrylate.

Other examples of the ionizing radiation curable resins include monofunctional or polyfunctional monomers such as styrene, methylstyrene, and N-vinylpyrrolidone, bisphenol type epoxy compounds, novolac type epoxy compounds, aromatic vinyl ethers, aliphatic vinyl ethers, and the like. The compound which has cationically polymerizable functional groups, such as an oligomer and a prepolymer, is mentioned.

The composition for antiglare layer formation containing an ionizing radiation curable resin may further contain a photoinitiator. Specific examples of the photopolymerization initiator include acetophenones, benzophenones, Michler's benzoyl benzoate, α-amyl oxime ester, tetramethylthiuram monosulfide, thioxanthones and the like.

The composition for forming the antiglare layer may further include a photosensitizer and a photopolymerization accelerator as necessary. The photosensitizer and the photopolymerization accelerator may be known photosensitizers, and specific examples thereof include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, α-methylbenzoin and α-phenylbenzoin. Benzoin compounds; anthratunone compounds such as anthraquinone and methyl anthraquinone; benzyl; diacetyl; phenyl ketone compounds such as acetphenone and benzophenone; sulfide compounds such as diphenyl disulfide and tetramethylthiuram sulfide; Chloromethyl naphthalene; halogenated hydrocarbons such as anthracene, hexachlorobutadiene, pentachlorobutadiene, thioxanthone, n-butylamine, triethylamine, tri-n-butyl phosphine, and the like. Preferably, a benzophenone or thioxanthone photosensitizer may be used for the acetphenone-based photopolymerization initiator.

When the solvent-drying resin is used in combination with the ionizing radiation curable resin, it is possible to prevent coating film defects on the coated surface when forming the square layer. The solvent-drying resin may be a thermoplastic resin, specific examples of the thermoplastic resin Vinyl acetate and its copolymers, vinyl chloride and its copolymers, vinyl resins such as vinylidene chloride and its copolymers, acetal resins such as polyvinyl formal and polyvinyl butyral, acrylic resins and their copolymers, and meta Acrylic resins such as acrylic resins and copolymers thereof, polystyrene resins, polyamide resins, polyester resins, polycarbonate resins, cellulose derivatives, cellulose resins, silicone resins and rubbers or elastomers.

The solvent-drying resin may be selected according to the type of the transparent base film, when the material of the transparent base film is a cellulose resin such as triacetyl cellulose may be used a cellulose resin. By using cellulose resin, the adhesiveness of a transparent base film and an anti-glare layer can be improved.

Specific examples of the cellulose resins include nitrocellulose, acetyl cellulose, cellulose acetate propionate, ethyl hydroxyethyl cellulose, and the like.

Specific examples of the thermosetting resin include phenol resins, urea resins, diallyl phthalate resins, melanin resins, guanamine resins, unsaturated polyester resins, polyurethane resins, epoxy resins, aminoalkyd resins, melamine-urea copolymer resins, silicon resins, and polysiloxanes. Resin and the like.

The antiglare layer resin composition including the thermosetting resin may further include a crosslinking agent, a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier, and the like.

The content of the resin is preferably 10 to 80 parts by weight based on 100 parts by weight of the total composition for antiglare layer forming. When the resin is less than 10 parts by weight, it is difficult to form a sufficient anti-glare layer thickness, and when it exceeds 80 parts by weight, workability may decrease due to an increase in the viscosity of the composition for forming an anti-glare layer.

The composition for antiglare layer formation may further contain a solvent. Specifically, the solvent may be alcohol-based (methanol, ethanol, isopropanol, butanol, methylcellulose, ethyl solusorb, etc.), ketone-based (methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone , Cyclohexanone, etc.), hexane-based (hexane, heptane, octane, etc.), benzene-based (benzene, toluene, xylene, etc.) and the like, and the illustrated solvents may be used alone or in combination of two or more, respectively. It is possible. Although the content of the solvent is not limited, it is preferable that 0.1 to 85 parts by weight based on 100 parts by weight of the total composition for forming an antiglare layer. If the content of the solvent is less than 0.1 parts by weight, the viscosity of the antiglare layer-forming composition is high workability, if more than 85 parts by weight may cause a problem that takes a lot of time in the drying and curing process.

It is preferable that the thickness of the anti-glare layer formed from the composition for anti-glare layer formation mentioned above is 1-30 micrometers, More preferably, it is 1-20 micrometers, Most preferably, it is 3-16 micrometers.

The antiglare layer may be formed by preparing a composition for forming an antiglare layer and then applying the same to a transparent base film. After dissolving the resin in a solvent, the fine particles are added and stirred, and the additive is slowly added to the stirred solution for 10 minutes to adjust the aggregation size of the particles; to prepare a composition for forming an antiglare layer.

The antiglare layer-forming composition thus prepared is applied to a transparent base film, dried and cured to form an antiglare layer. The coated antiglare layer-forming composition is preferably dried by evaporating the solvent for 10 seconds to 30 minutes at a temperature of 30 to 150 ° C, more preferably for 30 seconds to 10 minutes.

Next, the dried antiglare film-forming composition is cured to form an antiglare layer. In the case of photocuring, it is preferable that the irradiation amount of UV light is about 0.01-10 J / cm <2>, More preferably, it is effective to irradiate and harden at 0.1-2J / cm <2>.

The method of applying the composition for forming the antiglare layer is not particularly limited and may be, for example, performed in a suitable manner selected from a die coater, air knife, reverse roll, spray, blade, casting, gravure, micro gravure, or spin coating. Can be.

In addition, the optical laminate may further include a low refractive layer on top of the antiglare layer. The low refraction layer is preferably formed of a composition for forming a low refraction layer including a low refractivity agent and a low refractivity resin.

The low refractive index agent is not limited as long as it is a crystalline, amorphous or semi-crystalline inorganic particle having a low refractive index such as silica and magnesium fluoride, and the particle shape can also be used without restrictions such as spherical, amorphous, porous or hollow. Particularly, it is effective to use the monodisperse spherical hollow silica particles so as to improve the antireflection characteristic while improving the scratch resistance while lowering the refractive index.

The refractive index of the hollow silica particles measured using an Abbe refractive index meter (ATAGO Co., Ltd.) is preferably 1.17 to 1.40, more preferably 1.17 to 1.35, and most preferably 1.17 to 1.30 has scratch resistance and antireflection characteristics. It is effective for improvement. The refractive index of the hollow silica particles is not the refractive index of the outer portion forming the hollow particles, but means the refractive index of the entire particle.

The hollow silica particles may have a reduced thickness of the outer edge in order to achieve a low refractive index and may reduce the strength of the particles. Therefore, when the refractive index is less than 1.17, the scratch resistance of the low refractive index layer may be lowered. When the refractive index is greater than 1.40, the antireflection property may be deteriorated due to the high refractive index.

In order to realize the optimum strength and refractive index of the hollow silica particles, the porosity in the particles is preferably 10 to 60%, more preferably 20 to 60%, and most preferably 30 to 60%.

The average diameter of the hollow silica particles is preferably 30 to 150% of the low refractive layer thickness, more preferably 35 to 80%, and most preferably 40 to 60%. For example, when the thickness of the low refractive layer is 100 nm, 30 to 150 nm of the hollow silica particles are preferable, more preferably 35 to 80 nm, and most preferably 40 to 60 nm. When the average diameter of the hollow silica particles is in the above range, the ratio of the hollow portion may be increased to achieve a low refractive index, and to prevent a decrease in reflectance of the surface of the low refractive layer.

The low refractive index resin may be representatively exemplified a fluorine resin, and the fluorine resin may be a polymerizable compound or polymer thereof including at least one fluorine atom in a molecule.

The polymerizable compound may be a compound having a curable reactive group such as a functional group or a thermosetting functional group that is cured by ionizing radiation, or may be a compound having both such reactive groups at the same time. In addition, a polymer is a compound which does not contain the reactive group mentioned above.

The polymerizable compound having an ionizing radiation curable group may use fluoro olefins as a fluorine-containing monomer having an ethylenically unsaturated bond, more specifically fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, Perfluorobutadiene, perfluoro-2,2-dimethyl-1,3-dioxol, and the like.

In addition, the fluorine-containing monomer may include a (meth) acryloyloxy group, for example, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-penta Fluoropropyl (meth) acrylate, 2- (perfluorobutyl) ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth ) Acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, α-trifluoromethacrylate methyl, α-trifluoromethacrylate ethyl and the like can be exemplified.

The polymerizable compound having an ionizing radiation curable group also includes (C 1 -C 14) fluoroalkyl, (C 1 -C 14) fluorocycloalkyl, (C 1 -C 14) fluoroalkylene containing at least 3 fluorine atoms and And a fluorine-containing polyfunctional (meth) acrylic acid ester compound containing at least two (meth) acryloyloxy groups.

Moreover, thermosetting reactors, such as a hydroxyl group, a carboxy group, an amino group, or an epoxy group, are effective because they form a hydrogen bond, improve adhesiveness with a coating film, and are excellent also in affinity with inorganic particles, such as a silica.

Therefore, as a specific example of the fluorine-containing polymerizable compound including a thermosetting reactor, 4-fluoroethylene-fluoroalkyl vinyl ether copolymer or fluoroethylene-hydrocarbon-based vinyl ether copolymer may be used, and epoxy, polyurethane, Fluorine-modified resins containing fluorine in resins such as cellulose, phenol and polyimide can be used.

Specific examples of the polymerizable compound having an ionizing radiation curable group and a thermosetting reactor include partial acryl or methacrylic acid and fully fluorinated alkyl, alkenyl, aryl esters, fully or partially fluorinated vinyl ethers, fully or partially fluorinated vinyl esters, Full or partial fluorinated vinyl ketones etc. are mentioned.

Specific examples of the polymer containing a fluorine atom in the fluorine resin include polymers of monomers or monomer mixtures containing at least one fluorine-containing (meth) acrylate compound; at least one kind of fluorine-containing (meth) acrylate compound and methyl ( (Meth) acryl which does not contain a fluorine atom in the molecule, such as meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate Copolymers of late compounds; fluoroethylene, vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, 3,3,3-trifluoropropylene, 1,1,2-trichloro-3,3,3 And homopolymers or copolymers of fluorine-containing monomers such as -trifluoropropylene and hexafluoropropylene.

Silicon-containing vinylidene fluoride copolymers containing a silicone component in these copolymers may also be used. Specific examples of the silicone component include (poly) dimethylsiloxane, (poly) diethylsiloxane, (poly) diphenylsiloxane, (poly) methylphenylsiloxane, alkyl-modified (poly) dimethylsiloxane, azo group-containing (poly) dimethylsiloxane, dimethylsilicone, Phenylmethyl silicone, alkyl aralkyl modified silicone, fluorosilicone, polyether modified silicone, fatty acid ester modified silicone, methyl hydrogen silicone, silanol group-containing silicone, alkoxy group-containing silicone, phenol group-containing silicone, methacryl modified silicone, acrylic Modified silicones, amino modified silicones, carboxylic acid modified silicones, carbinol modified silicones, epoxy modified silicones, mercapto modified silicones, fluorine modified silicones, polyether modified silicones, and the like, and it is preferable to include dimethylsiloxane components. to be.

In addition, another compound that can be used as a fluorine-based resin is to react a fluorine-containing compound having at least one isocyanate group in the molecule and a compound having at least one functional group in the molecule, such as amino, hydroxy, carboxyl groups that can react with the isocyanate group Compound obtained; The compound etc. which are obtained by making fluorine-containing polyol, such as a fluorine-containing polyether polyol, a fluorine-containing alkyl polyol, a fluorine-containing polyester polyol, and a fluorine-containing (epsilon) -caprolactone modified polyol, react with the compound which has an isocyanate group, etc. are mentioned.

The composition for forming the low refractive index layer may further include an ionizing radiation curable resin used in the antiglare layer, in addition to the low refractive index agent and the low refractive index resin, to improve the curing agent, coating processability, or antifouling property for curing the reactive group. In order to provide, various additives, solvents and the like may be further included.

The solvent can be used without limitation as long as the low refractive index agent and the low refractive index resin can be uniformly mixed, and more specifically, toluene, xylene, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, propyl acetate, and MEK (methyl ethyl). Ketones), MIBK (methylisobutyl ketone) or mixtures thereof.

The thickness of the low refractive index layer formed of the composition for forming a low refractive index is preferably 10 to 500 nm, and more preferably 50 to 300 nm is effective to realize sufficient antireflection characteristics.

It is preferable that the refractive index in 25 degreeC exists in the range of 1.20-1.49 from the optical design for obtaining an optical laminated body of a low refractive layer. If the refractive index of the low refractive index layer is less than 1.20, the antireflection property may be reduced, and if the refractive index is greater than 1.49, the color of the reflected light may be enhanced.

Therefore, it is preferable that the antiglare layer and the low refractive layer constituting the optical laminated body satisfy the following expressions 5 and 6 in order to improve the antiglare property and the antireflection property.

1.20 ≤ R _Low ≤ 1.49 [Equation 5]

1 <R _AG / R _Low ≤ 1.8 [Equation 6]

When the refractive index of the antiglare layer and the refractive index of the low refractive index layer is less than 1, it is difficult to implement black reproducibility due to a slight difference in refractive index. When the refractive index ratio is more than 1.8, the anti-glare effect may be reduced.

The low refractive index layer is preferably formed by applying a low refractive index layer-forming composition prepared by mixing a low refractive index agent and a low refractive index resin to the upper portion of the antiglare layer. More specifically, after applying the composition for forming the low refractive index layer on the antiglare layer, the solvent is evaporated to dry for 10 seconds to 30 minutes at a temperature of 30 to 150 ℃, more preferably for 30 seconds to 10 minutes, and then UV light Irradiate and harden | cure. It is preferable that it is about 0.01-10J / cm <2>, and, as for the irradiation amount of UV light, it is more preferable that it is 0.1-2J / cm <2>.

There is no limit to the method of applying the composition for forming the low refractive index layer, for example, a die coater, air knife, reverse roll, spray, blade, casting, gravure, microgravure or spin coating, etc. Can be.

As described above, the optical laminated body having the anti-glare layer and the low refractive layer on the transparent base film may satisfy the following Equations 3 and 4 to optimize the anti-glare property, black reproducibility and anti-glare property.

0.1% ≤ H _t ≤ 2.0% [Equation 3]

0 <H _t -H _o ≤ 0.5 [Equation 4]

(In Formulas 3 and 4, H _t is the total haze value (%), and H _o represents the external haze value (%).)

As shown in Equation 4, the difference between the total haze and the external haze is preferably 0 to 0.5, and when the difference between the total haze and the external haze is greater than 0.5, the black reproducibility is increased due to the increase in the internal scattering of the optical stack when light is incident. This may be reduced.

The present invention also relates to a polarizing plate including the above-described optical laminate, and preferably includes an optical laminate on one or both surfaces of the polarizing film. For example, the antiglare layer made of the antiglare layer forming composition may be a polarizing plate formed on one surface of the polarizing film.

Examples of the polarizing film include a film uniaxially stretched by adsorbing a dichroic substance such as iodine or a dichroic dye to a hydrophilic polymer film such as a polyvinyl alcohol film or an ethylene-vinyl acetate copolymerized partial saponified film. Polyene type oriented films, such as a dehydration thing and the dehydrochlorination thing of polyvinyl chloride, etc. can be illustrated. Preferably, a polarizing film made of a dichroic substance such as a polyvinyl alcohol film and iodine may be used, and the thickness of these polarizing films is not particularly limited, but is generally 5 to 80 μm.

The present invention also relates to a display device including the above-described optical laminated body or polarizing plate. The optical stacked body may be a display device attached to a window of the display device, or may be a display device having a polarizing plate on the surface of the display device.

The display device can implement not only visibility but also excellent light diffusivity, transmission sharpness, and good front luminance.

The display device may be a reflection type, a transmissive type, a semi-transmissive type LCD, various driving type LCDs such as TN type, STN type, OCB type, HAN type, VA type or IPS type, plasma display, field emission display, organic EL display, An EL display, or a display device such as an electronic paper or the like.

Since the display device may be easily formed by adopting a configuration known in the art, except for applying the polarizing plate or the optical laminated body according to the present invention, a detailed description thereof will be omitted.

Although the content of this invention is demonstrated by the following embodiment, the content of this invention is not interpreted limited to these embodiment.

Property evaluation

(1) black reproducibility evaluation

After bonding to the cross nicol polarizing plate on the opposite side to the film surface of the optical laminated body of an Example and a comparative example, sensory evaluation was performed under 3 wavelength fluorescence, and black reproducibility was evaluated in detail by the following reference | standard, and the result is shown in Table 3.

○: reproduces a glossy black

△: slightly reproduces the glossy black

×: unable to reproduce glossy black

(2) flashing evaluation

On the HAKUBA Viewer (Light Viewer 7000PRO), place a black matrix pattern plate (75 ppi, 100 ppi) formed on 0.7 mm thick glass under the pattern surface, and place the optical laminate on the uneven surface as an air layer and prevent the film from floating. Gently pressing the end of the finger with the naked eye in the dark room was evaluated by visual observation and the results are shown in Table 3 below.

○: No flash was recognized at 100 ppi.

(Triangle | delta): No flash was recognized at 75 ppi.

X: Flashing was recognized at 75 ppi.

(3) Anti-glare evaluation

The back surface of the optical laminated body obtained by the Example and the comparative example was adhesive-processed, and what stuck to the black acrylic plate was made into the sample for evaluation. A black and white striped plate having a width of 20 mm was prepared, and the sample (the sample plane was tilted upward by about 30 degrees) was observed by illuminating the stripe at an angle of 20 degrees from the normal of the sample plane. At this time, the illuminance of the sample surface was 250 lx (lux), and the luminance (white) of the stripe was 65 cd / m 2. In addition, the distance of a stripe board and a sample was 1.5 m, and the distance of a sample and an observer was 1 m. This was defined and evaluated as follows according to the visible way of the stripes when the observer sees, the results are shown in Table 3 below.

○: We could not recognize stripe at all

(Triangle | delta): Although stripe was recognized a little, it was not enough to mind

X: The stripe was recognized.

[ Manufacturing example One]

Anticyclone layer Composition for forming

40 parts by weight of pentaerythritol triacrylate, an ultraviolet curable resin (M340, Miwon Co., Ltd.), 2 parts by weight of silica particles (Purisol MK82, Gamatek, average particle diameter 5nm, solid content 40% in MIBK) as fine particles, igure 184 as a photoinitiator. (BASF) 4 parts by weight, 0.1 parts by weight of BYK LPG21241 (BYK Chemical) as a leveling agent, 53.9 parts by weight of isopropyl alcohol (IPA, large purified gold) as a solvent was sufficiently mixed to prepare a composition. The composition was filtered with a filter of PP material having a diameter of 50 µm to prepare a composition for forming an antiglare layer. The components for the composition are shown in Table 1.

[ Manufacturing example 2 ~ 7]

The ultraviolet curable resin and silica particles were prepared in the same manner as in Preparation Example 1, except that the content of Table 1 was changed.

[Table 1]

[ Manufacturing example 8]

For low refractive index layer Composition

Promote adhesion to 10 parts by weight of a hollow silica-containing UV coating liquid (MB1030: Catalytic Chemical: 5% solids, about 3% by weight of hollow silica, polymerizable monomer, polymerization initiator) 3 parts by weight of zero 1,3,5-triamino-2,4,6-triazine (TCI), 5 parts by weight of isopropanol and 3 parts by weight of ethyl acetate were added and stirred at room temperature for 30 minutes, which was then 3 µm. The composition for forming a low refractive index layer having a refractive index of 1.34 was prepared by filtration through a polypropylene filter having an average pore of.

[ Manufacturing example 9]

For low refractive index layer Composition

Methyl ethyl ketone 5 in 10 parts by weight of a commercially available low refractive index layer-forming composition containing a fluoropolymer UV coating liquid (Addison: 20% solids concentration, about 85% by weight of fluoropolymer in solids, polymerizable monomer, polymerization initiator) After adding 3 parts by weight and 3 parts by weight of ethyl acetate and stirring at room temperature for 30 minutes, it was filtered through a polypropylene filter having an average pore size of 3 μm to prepare a composition for forming a low refractive index layer having a refractive index of 1.41.

[ Example One]

Anticyclone layer formation

A triacetyl cellulose film having a thickness of 80 μm was used as a transparent substrate, and the antiglare layer forming composition prepared in Preparation Example 1 was applied on the film using a myer bar, and dried by heating in an oven at 70 ° C. for 1 minute to evaporate the solvent. After irradiating UV irradiation to 500mJ to cure the cured film to form an anti-glare layer having a film thickness of 6㎛.

The low refractive index layer formation

Apply the composition 8 for low-refractive index layer composition to the top of the anti-glare layer using a Myer bar, heat-dry for 1 minute in an oven at 70 ° C. to evaporate the solvent, and irradiate UV cured film to 200mJ under nitrogen purge to give a cured film. It hardened | cured and the low refractive index layer of 100 nm of film thickness was formed.

The uneven shape, thickness and haze of the optical laminate formed from Example 1 were measured and presented in Table 2 below.

[ Example 2 ~ 12]

As shown in Table 2 below, to form an antiglare layer with a composition for forming an antiglare layer prepared in Preparation Examples 2 to 4, and to form a low refractive layer with the composition for forming a low refractive index prepared in Preparation Examples 8 to 9 Except for the optical laminated body was prepared in the same manner as in Example 1, the thickness of the anti-glare layer was formed to 6㎛, the thickness of the low refractive layer was formed to 100nm.

Uneven | corrugated shape, thickness, and haze of the optical laminated body formed from Examples 2-12 were measured, and are shown in following Table 2.

[ Comparative Example One]

Preparation Example 7 was used as a composition for forming an antiglare layer, and an optical laminated body was manufactured in the same manner as in Example 1 except that the composition for forming a low refractive index was used and the thickness of the antiglare layer was 6 μm. The low refractive index layer was formed to a thickness of 100 nm.

Unevenness, thickness and haze of the optical laminate formed from Comparative Example 1 were measured and shown in Table 2 below.

[ Comparative Example 2]

Preparation Example 7 was used as a composition for forming an antiglare layer, and an optical laminated body was manufactured in the same manner as in Example 1 except that the composition for forming a low refractive index was used in Example 1, and the thickness of the antiglare layer was 6 μm. The low refractive index layer was formed to a thickness of 100 nm.

The unevenness, thickness and haze of the optical laminate formed from Comparative Example 2 were measured and shown in Table 2 below.

[Comparative Example 3]

Except for using the composition for forming a low refractive index 9 was prepared in the same manner as in Example 1, an optical laminated body was not formed, the thickness of the low refractive index layer was formed to 100nm.

The unevenness, thickness and haze of the optical laminate formed from Comparative Example 3 were measured and shown in Table 2 below.

[Comparative Example 4]

40 parts by weight of pentaerythritol triacrylate, 0.1 parts by weight of photoinitiator (Igacure 184), 4 parts by weight of additive (BYK LPG21241), 55.8 parts by weight of solvent (isopropyl alcohol) as a composition for forming an antiglare layer To form an antiglare layer, and then cured to form an antiglare layer, and a composition for forming a low refractive index layer prepared in Preparation Example 8 was applied to the upper surface thereof at 100 nm to prepare an optical laminate.

The unevenness, thickness and haze of the optical laminate formed from Comparative Example 4 were measured and shown in Table 2 below.

[Table 2]

[Table 3]

Looking at the embodiment, it can be confirmed that the anti-glare is excellent when the optical laminated body is included in the range of the surface roughness parameter (Ra) and when the difference between the total haze and the external haze is included in the range. In addition, it can be confirmed that the anti-glare property is exhibited while having an appropriate contrast that can provide excellent black reproducibility. On the other hand, as shown in the comparative example, when the surface roughness parameter Ra and the difference between the total haze and the external haze are out of the ranges set forth in the present invention, optical properties such as anti-glare property, black reproducibility, and flashing are deteriorated. You can see that.

Therefore, the optical laminated body within the range of the surface roughness parameter Ra and the difference between the total haze and the external haze within the range can be effectively applied to a display device requiring high precision because of excellent anti-glare property and optical properties.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the above description should not be construed as limiting the scope of the present invention defined by the limits of the following claims.

Claims

A transparent base film; And
An optical laminated body including; provided on the transparent base film, the anti-glare layer having an uneven portion;
The uneven portion is formed of an aggregate (P) that satisfies the following formula 1 and formula 2 in which 1 to 1000 fine particles having an average particle diameter of 1 to 100 nm are aggregated,
1 µm ≤ P _a ≤ 100 µm [Equation 1]
1.0 ≤ P _max / P _min ≤ 50 [Equation 2]
Arithmetic mean surface roughness (Ra) of the antiglare layer is 0.01 to 0.1㎛,
The optical laminated body satisfies the following formula 3 and formula 4.
0.1% ≤ H _t ≤ 2.0% [Equation 3]
0 <H _t -H _o ≤ 0.5 [Equation 4]
(A in the formula 1 and the formula 2 P _a is an average agglomerated light, P _max is the diameter of the maximum aggregation (㎛), P _min is a minimum aggregate diameter (㎛) of the aggregates, H _t is from Equation 3 and Equation 4 Total haze value (%), H _o represents external haze value (%).)

The method of claim 1,
The optical laminated body further comprises a low refractive layer on the anti-glare layer, the following formula 5 and formula 6.
1.20 ≤ R _Low ≤ 1.49 [Equation 5]
1 <R _AG / R _Low ≤ 1.8 [Equation 6]
(In Formulas 5 and 6, R _AG is the refractive index of the antiglare layer, and R _Low is the refractive index of the low refractive layer.)

The method of claim 1,
The antiglare layer is an optical lamination agent comprising a compound represented by the following formula (1).
[Chemical Formula 1]

The method of claim 1,
The antiglare layer is formed from a composition for forming an antiglare layer comprising the aggregate and the resin,
The content of the fine particles are included 0.01 to 2 parts by weight based on 100 parts by weight of the total antiglare layer forming composition,
Said resin is 1 type or 2 types chosen from an ionizing radiation curable resin, a solvent drying type resin, and a thermosetting resin.

5. The method of claim 4,
The composition for forming the antiglare layer further comprises a modified silicone-based leveling agent, wherein the content of the leveling agent comprises 0.01 to 1 parts by weight based on 100 parts by weight of the total anti-glare layer forming composition.

3. The method of claim 2,
The thickness of the anti-glare layer is 1 to 30㎛, the thickness of the low refractive layer is an optical laminated body, characterized in that 0.01 to 0.5㎛.

Claim 1 to 6, wherein the polarizing film comprising any one of the optical laminated body selected from claim 1 on either side or both sides of the polarizing film.

A display device comprising the polarizing plate of claim 7.

The method of claim 8,
The display device is a liquid crystal display (LCD), plasma display, field emission display, organic EL display, inorganic EL display or electronic paper selected from TN type, STN type, OCB type, HAN type, VA type and IPS type. .

A display device comprising the optical stack of any one of claims 1 to 6.