TW202014735A - Anti-glare film, and production method and use therefor - Google Patents

Abstract

The present invention provides an anti-glare film having both anti-glare properties and scratch resistance. The surface shape of an anti-glare layer included in the anti-glare film is adjusted to have a skewness Rsk that is less than 0 and the average length RSm of roughness curve elements of 1-50 [mu]m. The anti-glare layer preferably does not contain particles with a particle size of 3 [mu]m or greater. It is particularly preferable that the anti-glare layer contains no particles. The haze of the anti-glare film may be 1-60%. The 60 degree gloss of the surface of the anti-glare layer may be 1-70%. The anti-glare layer may be a cured product of a curable composition that contains a photocurable resin. The anti-glare film may be produced through a transfer film formation process of forming a transfer surface by causing phase separation via wet spinodal decomposition and a transfer process of using the obtained transfer surface of the transfer film as a mold to form an uneven shape that is an inverted shape of the transfer surface on the transfer receiving surface of an anti-glare film precursor. The anti-glare film may be used as an anti-glare film for a liquid crystal display device with a touch panel or an organic EL display.

Description

Anti-glare film and its manufacturing method and use

The present invention relates to an anti-glare film which is suitable for preventing external light sources from being reflected on the display surface of various display devices and is not easily scratched by friction.

The anti-glare film is widely used as a film to prevent external scenery from being reflected on the display surface of an image display device such as a liquid crystal display device (LCD) or an organic electroluminescence (EL) display, and to suppress glare and improve visibility. The anti-glare film exhibits anti-glare properties by forming a concave-convex shape on the surface to scatter and reflect external light. Depending on the application, it also requires hard coating or scratch resistance. In the anti-glare film, as a method of forming an anti-glare layer having hard coating properties, a method of roughening the surface of the anti-glare layer by physical methods (physical roughening method), by a binder A method of forming irregularities on the surface of the anti-glare layer by adding resin particles (particle addition method), a method of forming irregularities on the surface of the anti-glare layer by phase separation of resin components (phase separation method), etc.

As an anti-glare film obtained by a physical roughening method, Japanese Unexamined Patent Publication No. 2014-47300 (Patent Document 1) discloses that it is formed by transfer from a mold having irregularities and has an arithmetic average roughness Ra It is an optical member with a concave-convex shape of 0.005~2.5 μm.

As an anti-glare film obtained by the particle addition method, Japanese Unexamined Patent Publication No. 2014-16602 (Patent Document 2) discloses an anti-glare film having an anti-glare layer including an average primary particle diameter of 1 to 100 nm silicon oxide fine particles, organic fine particles with an average particle size of 0.5~5 μm and binder, and the average interval Sm of the unevenness is 50 μm<Sm<600 μm, the arithmetic average roughness Ra of the unevenness is 0.02 μm<Ra<0.25 μm. In addition, Japanese Unexamined Patent Publication No. 2012-98734 (Patent Document 3) discloses that it has fine particles including an average particle diameter of 1 to 20 μm and a curable resin, and has an uneven roughness Rz of 0.3 to 1.8 μm. Anti-glare film for the glare layer.

As an anti-glare film obtained by a phase separation method, Japanese Patent Laid-Open No. 2009-276772 (Patent Document 4) discloses an anti-glare film that is contained on the surface and has spinodal decomposition from the liquid phase (spinodal decomposition) and the anti-glare layer of the concave-convex structure formed by phase separation, and the incident light penetrates and scatters isotropically, the scattering angle representing the maximum value of the scattered light intensity is 0.1~10°, and the haze is 20~ 50%. In addition, Japanese Patent Laid-Open No. 2014-85371 (Patent Document 5) discloses an anti-glare film that includes elongated convex portions having a co-continuous phase structure formed on the surface accompanying the phase separation of various resin components, And the anti-glare layer with 60° gloss is more than 30, and the haze is 10~40%. Furthermore, Japanese Patent Laid-Open No. 2014-92657 (Patent Document 6) discloses a surface film for a multi-touch display surface in which irregularities caused by phase separation structures of a plurality of polymers are formed on the surface, The haze is 15 to 50%, and the three-dimensional arithmetic average roughness Sa of the surface is 0.15 to 1 μm.

However, although the anti-glare layer can exhibit anti-glare properties, the scratch resistance is insufficient. In detail, when the surface of the anti-glare film is rubbed, since the convex portion of the surface is rubbed, depending on the friction material, speed, length, load, number of rubbing times and other conditions, the wear and tear of the concave-convex shape occurs, using particles The anti-glare layer obtained by the addition method may cause particles to fall off. [Prior Technical Literature] [Patent Literature]

Patent Literature 1: Japanese Patent Laid-Open No. 2014-47300 (Request 7) Patent Document 2: Japanese Patent Laid-Open No. 2014-16602 (Request 1, Paragraph [0035][0049]) Patent Document 3: Japanese Patent Laid-Open No. 2012-98734 (Request Item 1, Paragraph [0027][0035]) Patent Document 4: Japanese Patent Laid-Open No. 2009-276772 (request item 1, paragraph [0076]) Patent Document 5: Japanese Patent Laid-Open No. 2014-85371 (Request Item 1, Paragraph [0095] [0102]) Patent Document 6: Japanese Patent Laid-Open No. 2014-92657 (Request 1)

[Problems to be solved by the invention]

Therefore, an object of the present invention is to provide an anti-glare film having both anti-glare properties and scratch resistance, as well as a manufacturing method and use thereof. [Technical means to solve the problem]

The inventor has made intensive studies to achieve the above-mentioned problems, and found that by adjusting the surface shape of the anti-glare layer to a shape where the skewness Rsk is less than 0 and the average length RSm of the roughness curve elements is 1 to 50 μm, and The invention can be completed with both anti-glare properties and scratch resistance.

That is, the anti-glare film of the present invention includes an anti-glare layer having a surface shape in which the skewness Rsk is less than 0 and the average length RSm of the roughness curve elements is 1 to 50 μm. The anti-glare layer preferably does not contain particles having a particle diameter of 3 μm or more, and particularly preferably does not contain particles. The haze of the anti-glare film can be 1 to 60%. The 60° gloss of the surface of the anti-glare layer may be 1 to 70%. The anti-glare layer may be a cured product of a curable composition containing a photo-curable resin.

The present invention also includes a method for manufacturing the anti-glare film. The manufacturing method includes a transfer step in which the transfer surface of the transfer film is used as a forming mold, and the transfer surface of the anti-glare film precursor is formed as the transfer surface. The inverted shape of the bumpy shape. The manufacturing method may further include a transfer film forming step, which is phase-separated by the decomposition of the wet knuckle to form a transfer surface.

The present invention also includes a display device provided with the anti-glare film. The display device may be a liquid crystal display device with a touch panel or an organic EL display. [Effect of invention]

In the present invention, since the surface shape of the anti-glare layer is adjusted to a shape where the skewness Rsk is less than 0 and the average length RSm of the roughness curve elements is 1 to 50 μm, it can have both anti-glare properties and scratch resistance.

[Anti-glare layer] The anti-glare film of the present invention includes an anti-glare layer having a surface shape with a skewness Rsk less than 0 and an average length RSm of the roughness curve elements of 1 to 50 μm. The reason why the anti-glare layer having such a surface shape can have both anti-glare properties and scratch resistance is not clear, but it can be presumed that the surface shape that satisfies the above Rsk and RSm has the following shape: the friction surface of the convex portion is flat and relatively Large, many small depressions are formed between the convex parts with such a flat friction surface; even if the friction friction surface is repeated, since it is flat and large, wear is still suppressed, and it is also ensured by multiple small depressions Anti-glare.

The skewness Rsk (skewness) of the surface of the anti-glare layer is an index for evaluating the symmetry of the height distribution, as long as it does not reach 0, for example, -10 or more and 0, preferably -5 to -0.01, and It is preferably about -1 to -0.1 (particularly -0.5 to -0.2). If Rsk is 0 or more, the scratch resistance decreases.

The average length RSm of the roughness curve elements on the surface of the anti-glare layer may be 1 to 50 μm, for example, 2 to 40 μm, preferably 3 to 35 μm, and more preferably 5 to 30 μm (especially 10 to 25 μm). In applications requiring high scratch resistance, RSm can be around 10 to 30 μm (especially 20 to 25 μm). If RSm is too small, it may be difficult to control the size of the unevenness. Conversely, if RSm is too large, the anti-glare property may decrease.

The arithmetic average roughness Ra of the surface of the anti-glare layer is, for example, 0.01 to 1 μm (for example, 0.02 to 0.8 μm), preferably 0.03 to 0.7 μm, and more preferably about 0.04 to 0.6 μm (particularly 0.05 to 0.5 μm). In applications requiring high scratch resistance, Ra can be about 0.2~1 μm (especially 0.25~0.5 μm). If Ra is too small, the anti-glare property may decrease. Conversely, if Ra is too large, the scratch resistance may decrease.

The maximum cross-sectional height Rt of the roughness curve of the surface of the anti-glare layer is, for example, 0.1 to 3 μm, preferably 0.5 to 2.5 μm, and more preferably about 1 to 2 μm (especially 1.5 to 1.8 μm). If Rt is too small, the anti-glare property may decrease, and if Rt is too large, the scratch resistance may decrease.

In the scope of this specification and patent application, the skewness Rsk, the average length of roughness curve elements RSm, the arithmetic mean roughness Ra and the maximum section height Rt of the roughness curve can be based on the use of a non-contact surface-layer section shape measurement system [Ryoka "VertScan2.0" manufactured by Systems Co., Ltd.] was obtained by measuring the curve obtained by measuring the unevenness on the surface of the anti-glare layer. Specifically, it can be measured by the method described in the following examples.

The 60° gloss of the surface of the anti-glare layer is, for example, 1 to 70% (for example, 5 to 65%), preferably 2 to 60%, and more preferably about 3 to 55% (especially 5 to 50%). In applications requiring high scratch resistance, the 60° gloss can be around 5 to 30% (especially 10 to 20%). If the gloss at 60° is too small, the visibility may be reduced. On the contrary, if the gloss is too large, the anti-glare property may be reduced.

In the scope of this specification and patent application, 60° gloss can be measured in accordance with JIS K8741 using a gloss meter ("Poly gloss KT-GL0030" manufactured by TQC Corporation).

The anti-glare layer only needs to have the characteristics described above and the characteristics of the anti-glare film described below, and the material is not particularly limited. The material constituting the anti-glare layer can be selected from various transparent organic materials (thermoplastic resin, thermosetting resin, photo-curable resin, etc.) or inorganic materials (glass, ceramics, metal, etc.), but the scratch resistance and In terms of productivity and the like, it is preferably a cured product of a curable composition containing a curable resin.

(Curable resin) The curable resin may be either a thermosetting resin or a photocurable resin, and is preferably a photocurable resin in terms of productivity and the like. Photocurable resins (precursor components of photocurable resins) are compounds that can be cured or cross-linked by active energy rays such as ultraviolet rays or electron beams to form resins. They are roughly divided into photocurable resins that do not contain fluorine and those that contain fluorine. Photocurable resin.

The fluorine-free photo-curable resin contains monomers and oligomers (or resins, especially low molecular weight resins).

Examples of the monomer include monofunctional monomers [(meth)acrylic monomers such as (meth)acrylates, vinyl-based monomers such as vinylpyrrolidone, and isobutyl (meth)acrylate Ester, adamantyl (meth)acrylate, etc. (meth)acrylate etc. having a bridged cyclic hydrocarbon group], bifunctional monomer [ethylene glycol di(meth)acrylate, propylene glycol di(methyl) Alkylene glycol di(meth)acrylates such as acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate; Diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, polyoxytetramethylene glycol di(meth)acrylate, etc. (poly)oxyalkylene glycol di(meth) Group) acrylate; tricyclodecane dimethanol di(meth)acrylate, adamantane di(meth)acrylate and the like (di(meth)acrylate having a bridged cyclic hydrocarbon group], polyfunctional with more than 3 functions Sexual monomers [glycerol tri (meth) acrylate, trimethylol propane tri (meth) acrylate, trimethylol ethane tri (meth) acrylate, tetramethylol methane tri (meth) Acrylic ester, neopentyl alcohol tri (meth) acrylate, tri (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tetramethylol methane tetra (meth) acrylate, di -Trimethylolpropane tetra(meth)acrylate, neopentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate 3-6 functional monomers such as esters] etc. Among these, multifunctional (meth)acrylates having at least 2 (meth)acryloyl groups are commonly used.

Examples of oligomers or resins include: (meth)acrylates of bisphenol A-alkylene oxide adducts, epoxy (meth)acrylates [those with two or more (meth)acryloyl acrylate groups] Multifunctional epoxy (meth)acrylate], polyester (meth)acrylate [multifunctional polyester (meth)acrylate with two or more (meth)acryloyl acrylate groups], (meth ) Amine acrylate [multifunctional (meth) acrylate with more than 2 (meth)acryloyl groups], polysiloxane (meth)acrylate [have more than 2 (meth) acryl groups Polyfunctional polysiloxane (meth)acrylate], (meth)acrylic polymers with polymerizable groups, etc.

These fluorine-free photo-curable resins can be used alone or in combination of two or more. Among these, in terms of scratch resistance, polyfunctional monomers of 2 or more functionalities are preferred, and polyfunctional monomers of 3 or more functionalities are preferred, and polyfunctional monomers of 5 or more functionalities are particularly preferred. Sexual monomer.

The fluorine-free photocurable resin preferably contains 50% by mass or more of a trifunctional or more polyfunctional monomer, more preferably contains 80% by mass or more, and most preferably contains 90% by mass or more. The fluorine-free curable resin may only be a multifunctional monomer with more than 3 functions.

Fluorine-free photo-curable resins can be polyfunctional monomers with 4 or less functions (especially 3 to 4 functional monomers) and polyfunctional monomers with 5 or more functions (especially 5 to 8 functional monomers) ) Combination. When combining the two, the mass ratio of the polyfunctional monomer of less than 4 functions to the polyfunctional monomer of more than 5 functions is the former/the latter=90/10~1/99, preferably 50/50~ 2/98, and further preferably about 30/70 to 3/97 (especially 20/80 to 5/95).

The fluorine-containing photocurable resin may be a fluoride as the monomer and oligomer of the above-mentioned fluorine-free photocurable resin. As the photocurable resin containing fluorine, for example, fluorinated alkyl (meth)acrylate [for example, perfluorooctyl ethyl (meth)acrylate or trifluoroethyl (meth)acrylate, etc.], fluorine Polyoxyalkylene glycol di(meth)acrylate [eg fluoroethylene glycol di(meth)acrylate, fluoropolyethylene glycol di(meth)acrylate, fluoropropylene glycol di(meth)acrylic acid Ester etc.], fluorine-containing epoxy (meth)acrylate, fluorine-containing (meth)acrylate, etc. The fluorine-containing curable resin may be a commercially available fluorine-based polymerizable leveling agent.

These fluorine-containing photocurable resins can be used alone or in combination of two or more. Among these, a fluoropolyether compound having a (meth)acryloyl group and a fluorine-containing (meth)acrylate amine ester are preferred, and a fluorine-containing and ester-containing (meth)acrylate amine ester is particularly preferred.

The photo-curable resin preferably contains at least a photo-curable resin containing no fluorine, and particularly preferably a combination of a photo-curable resin containing no fluorine and a photo-curable resin containing fluorine. The ratio of the photocurable resin containing no fluorine may be 50% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more in the photocurable resin.

When combining a photocurable resin containing no fluorine and a photocurable resin containing fluorine, the ratio of the photocurable resin containing fluorine is, for example, 0.1 to 10 with respect to 100 parts by mass of the photocurable resin containing no fluorine. The part by mass is preferably 0.2 to 8 parts by mass, and more preferably 0.3 to 6 parts by mass (particularly 0.4 to 5 parts by mass). If the ratio of the fluorine-containing photocurable resin is too small, the surface modification effect may be reduced, and if it is too large, the scratch resistance may be reduced.

(Polymer component) The curable composition may contain a polymer component in addition to the curable resin (especially the photocurable resin) in terms of improving scratch resistance. As the polymer component, a thermoplastic resin is usually used. As the thermoplastic resin, as long as the transparency is high, for example, styrene resin, (meth)acrylic polymer, organic acid vinyl ester polymer, vinyl ether polymer, halogen-containing resin, polyolefin ( Including alicyclic polyolefin), polycarbonate, polyester, polyamide, thermoplastic polyurethane, poly-resin resin (polyether ballast, poly-resin, etc.), polyphenylene ether resin (2,6-xylenol Polymers, etc.), cellulose derivatives (cellulose esters, cellulose urethanes, cellulose ethers, etc.), polysiloxane resins (polydimethylsiloxane, polymethylphenylsilicone Alkane, etc.), fluororesin, rubber or elastomer (polybutadiene, polyisoprene and other butadiene rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylic rubber, Urethane rubber, silicone rubber, etc.) etc. These thermoplastic resins can be used alone or in combination of two or more.

Among these polymer components, in terms of being amorphous and soluble in organic solvents, styrene resins, (meth)acrylic polymers, alicyclic polyolefins, polyesters, Cellulose derivatives (cellulose esters, etc.), etc., particularly preferably cellulose esters.

Examples of the cellulose esters include aliphatic organic acid esters (cellulose acetate such as cellulose diacetate and cellulose triacetate; cellulose propionate, cellulose butyrate, and cellulose Propyl acetate, cellulose acetate butyrate, etc. C _1-6 aliphatic carboxylic acid esters, etc.), aromatic organic acid esters (cellulose phthalate, cellulose benzoate, etc. C _7-12 Aromatic carboxylic acid esters), inorganic acid esters (for example, cellulose phosphate, cellulose sulfate, etc.), etc. may also be mixed acid esters such as acetate-nitrocellulose ester. These cellulose esters can be used alone or in combination of two or more. Among these, C _2-4 cellulose such as cellulose diacetate, cellulose triacetate, cellulose acetate propionate and cellulose acetate butyrate is preferred, and cellulose is particularly preferred Propyl acetate and other C _3-4 acetylated cellulose acetate.

The ratio of the polymer component relative to 100 parts by mass of the curable resin is, for example, 0.1 to 30 parts by mass, preferably 0.5 to 10 parts by mass, and more preferably about 1 to 5 parts by mass (particularly 1.5 to 3 parts by mass). .

(filler) In order to achieve a balance between anti-glare properties and scratch resistance, the curable composition may further contain fillers (particles). As the filler, for example, inorganic particles such as silicon oxide particles, titanium oxide particles, zirconium oxide particles, aluminum oxide particles, zinc oxide particles, tin oxide particles, antimony oxide particles, tin-doped indium oxide (ITO) particles, cross-linked (a Based) Organic particles such as acrylic polymer particles, cross-linked styrene resin particles. These fillers can be used alone or in combination of two or more.

Among these fillers, silicon oxide particles are preferred in terms of easy combination of anti-glare properties and scratch resistance. In terms of improving the transparency of the anti-glare film, the silicon oxide particles are preferably solid silicon oxide particles.

The shape of the filler may be an anisotropic shape, but it is preferably an isotropic shape, particularly preferably a spherical shape. The average particle size of the filler may be less than 3 μm, for example, 1 to 1000 nm, preferably 3 to 500 nm, and more preferably about 5 to 100 nm (especially 10 to 30 nm). If the average particle size of the filler is too large, the scratch resistance may be reduced. In addition, the average particle diameter is expressed as a volume average primary particle diameter, which can be measured by a laser diffraction scattering method or the like.

The ratio of the filler to 100 parts by mass of the curable resin is, for example, 1 to 50 parts by mass, preferably 2 to 40 parts by mass, and more preferably about 3 to 30 parts by mass.

The filler may be in a form that has previously been reacted with the curable resin and modified by the curable resin.

In the present invention, in terms of scratch resistance, the anti-glare layer preferably does not substantially contain fillers (particles) having a particle diameter of 3 μm or more, and particularly preferably does not contain at all. As described above, the anti-glare layer preferably contains particles in terms of achieving a balance between anti-glare properties and scratch resistance, and particularly preferably contains fillers having a particle diameter of less than 3 μm. Furthermore, when high scratch resistance is required, the anti-glare layer preferably does not substantially contain the filler itself, and particularly preferably does not contain at all regardless of the particle size.

類、醯基氧化膦類等。相對於硬化性樹脂100質量份，光聚合起始劑等硬化劑之比率例如為0.1〜20質量份，較佳為0.5〜10質量份，進而較佳為1〜5質量份左右。(Other components) The curable composition may further contain a curing agent according to the type of curable resin. For example, the thermosetting resin may contain hardeners such as amines and polycarboxylic acids, and the photocurable resin may contain photopolymerization initiators. As the photopolymerization initiator, conventional components can be exemplified, for example: acetophenones or phenylacetones, benzoyls, benzoins, benzophenones, 9-oxysulfide

Class, acetyl phosphine oxide, etc. The ratio of the curing agent such as a photopolymerization initiator to 100 parts by mass of the curable resin is, for example, 0.1 to 20 parts by mass, preferably 0.5 to 10 parts by mass, and more preferably about 1 to 5 parts by mass.

The curable composition may further contain a curing accelerator. For example, the photocurable resin may contain a photohardening accelerator, such as tertiary amines (dialkylaminobenzoate, etc.), phosphine-based photopolymerization accelerators, and the like.

The hardenable composition may contain conventional additives, such as: silane coupling agent (such as silane coupling agent with thiol group, etc.), leveling agent, stabilizer (antioxidant, ultraviolet absorber, etc.), surfactant, water-soluble Polymers, fillers, cross-linking agents, coupling agents, colorants, flame retardants, lubricants, waxes, preservatives, viscosity modifiers, tackifiers, defoamers, etc. The ratio of the additives can be selected from the range of about 0.01 to 100 parts by mass relative to 100 parts by mass of the curable resin, for example, about 0.1 to 10 parts by mass (particularly 0.5 to 5 parts by mass).

(Thickness of anti-glare layer) The thickness (average thickness) of the anti-glare layer is, for example, 1 to 20 μm, preferably 2 to 15 μm, and more preferably about 3 to 10 μm (especially 5 to 8 μm). In addition, within the scope of this specification and patent application, the average thickness of each layer can be determined by measuring 10 arbitrary positions using an optical film thickness meter, and calculating the average value.

[Substrate layer] The anti-glare film of the present invention may be formed of the above-mentioned anti-glare layer alone, or may be formed of a base layer and an anti-glare layer formed on at least one side of the base layer. Among these, it is preferable to deposit an anti-glare layer on one side (only one side) of the base material layer in terms of operability, mechanical characteristics, productivity, and the like.

The base material layer may be formed using a transparent material and may be selected according to the application. It may be an inorganic material such as glass, but it is a general-purpose organic material in terms of strength and moldability. Examples of organic materials include cellulose derivatives, polyesters, polyamides, polyimides, polycarbonates, (meth)acrylic polymers, and the like. Among these, general-purpose cellulose ester, polyester, polycarbonate and the like are preferably polyester and polycarbonate.

Examples of the polyester include polyalkylene aryl esters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Examples of the polycarbonate include bisphenol-type polycarbonate.

Among these, in terms of excellent balance between mechanical properties and transparency, poly C _2-4 alkylene aryl esters such as PET or PEN, and bisphenol A polycarbonate are preferred, and versatility is considered In particular, poly C _2-3 alkylene aryl esters such as PET are particularly preferred.

The base material layer may contain the conventional additives exemplified in the section of the anti-glare layer. The ratio of additives is also the same as the anti-glare layer.

The base material layer may be a uniaxially or biaxially stretched film, and in terms of low birefringence and excellent optical isotropy, it may also be an unstretched film.

The substrate layer can be surface-treated (for example: corona discharge treatment, flame treatment, plasma treatment, ozone or ultraviolet irradiation treatment, etc.), or it can have an easy adhesion layer.

The thickness (average thickness) of the base material layer is, for example, 5 to 2000 μm, preferably 15 to 1000 μm, and more preferably about 20 to 500 μm.

[Characteristics of anti-glare film] The anti-glare film of the present invention is excellent in transparency and visibility. The haze of the anti-glare film of the present invention is, for example, 1 to 60%, preferably 5 to 55%, and more preferably about 10 to 50%. Furthermore, the haze of the anti-glare film of the present invention can be relatively high in terms of improving anti-glare properties, for example, 10 to 60%, preferably 30 to 55%, and more preferably 40 ~50%. If the haze is too low, the anti-glare property may decrease. Conversely, if the haze is too high, the visibility may decrease.

In addition, in the scope of this specification and patent application, the haze can be measured in accordance with JIS K7163 using a haze meter ("NDH-5000W" manufactured by Nippon Denshoku Industries Co., Ltd.).

The total light transmittance of the anti-glare film of the present invention is, for example, 70% or more (eg, 70-100%), preferably 80-99%, and more preferably 85-98% (especially 88-95%) . If the total light transmittance is too low, there is a risk that the transparency will decrease.

Furthermore, in the scope of this specification and patent application, the total light transmittance can be measured in accordance with JIS K7361 using a haze meter ("NDH-5000W" manufactured by Nippon Denshoku Industries Co., Ltd.).

The anti-glare film of the present invention can be combined with an adhesive layer, a low-refractive index layer, an anti-reflection layer, etc., which are conventional functional layers, in addition to the anti-glare layer and the base material layer.

The thickness (average thickness) of the anti-glare film of the present invention is, for example, 3 to 2000 μm, preferably 5 to 1000 μm, and more preferably about 10 to 500 μm.

[Manufacturing method of anti-glare film] The method for manufacturing the anti-glare film of the present invention is not particularly limited as long as it can form the uneven shape having the above Rsk and RSm on the surface of the anti-glare layer, and a conventional method can be used. As a conventional method, for example, a method of forming a concave-convex shape using particles (for example, a method of forming a convex portion following the particle shape), and after phase-separating the above-mentioned resin component of the curable composition containing a phase-separated resin component The method of hardening, the method of transferring using a mold with a concave-convex shape on the surface, the method of forming a concave-convex shape by cutting (for example, cutting processing using laser, etc.), the method of forming a concave-convex shape by grinding (for example, sandblasting) Method or jet bead method, etc.), a method of forming an uneven shape by etching, etc.

Among these, in terms of productivity and the like, a method of transferring using a mold having a concave-convex shape on the surface is preferred, and it is further preferred to include the transfer surface of the transfer film as a forming mold in the anti-glare film The method of transferring the surface of the precursor into a concave-convex shape which is the reverse shape of the transfer surface described above, preferably further includes the formation of a transfer film formed by phase separation by wet-knob decomposition to form a transfer surface The step serves as a method before the above transfer step.

In the above-mentioned film formation step for transfer, in the phase separation method using wet spinodal decomposition, the solvent is evaporated or removed from the liquid phase of the composition containing the phase-separated resin component and the solvent by drying or the like In the process, as the concentration continues to concentrate, phase separation caused by spinodal decomposition (wet spinodal decomposition) occurs, whereby the surface shape (converted by the phase separation structure) can be formed on the surface of the anti-glare layer to reverse the target concave-convex shape The resulting uneven shape). As the combination of the phase-separated resin components, there may be a combination of the photocurable resins exemplified in the item of the anti-glare layer, and the polymer component exemplified in the items of the photocurable resin and the anti-glare layer ( Any one of the combination of the thermoplastic resin and the combination of the above-mentioned polymer components may be, for example, a (meth)acrylic polymer (eg, polymethyl methacrylate, having a vinyl group, (meth)acryloyl group) (Meth)acrylic polymers such as polymerizable groups) and cellulose esters (cellulose acetate propionate and other C _3-4 acylated cellulose acetate, etc.) and/or (meth)acrylic acid amine Combination of esters, etc. As a method of utilizing phase separation, for example, Japanese Patent Publication 2007-187746, Japanese Patent Publication 2008-225195, Japanese Patent Publication 2009-267775, Japanese Patent Publication 2011-175601, Japanese Patent Publication 2014-85371, Japanese Patent Publication 2014 -92657, JP 2014-98771, JP 2016-161859, JP 2017-219622, etc.

In order to form a target uneven shape on the surface of the anti-glare layer as the surface to be transferred, the transfer surface of the transfer film obtained in the transfer film forming step can be adjusted to Rsk of 0 or more (for example, 0 to 3, preferably 0.1 to 1, and more preferably about 0.2 to 0.5), and RSm is about 1 to 50 μm (especially 1 to 30 μm).

Regarding the transfer surface, in order to smoothly peel off the anti-glare film obtained by hardening, the water contact angle can be adjusted to 90° or more (for example, 90 to 120°). The water contact angle of the transfer surface can be adjusted using, for example, a fluorine compound or a polysiloxane compound. Furthermore, in the scope of this specification and patent application, the water contact angle can be measured by a conventional method, for example, it can be measured using an automatic-dynamic contact angle meter.

In the above transfer step, as a method for transferring the target uneven shape on the transferred surface of the anti-glare film precursor, as long as the anti-glare film precursor and the anti-glare film precursor that can follow the uneven shape of the transfer surface of the transfer film The method of peeling the cured or hardened anti-glare film from the film for transfer after contacting the transfer surface to cure or harden the precursor is not particularly limited, and a conventional method can be appropriately selected according to the type of anti-glare film. As a specific method, a method of peeling the cured anti-glare film from the transfer film after the liquid anti-glare film precursor is formed in the mold with the transfer film embedded in the mold ( In-mold forming method); coating the liquid anti-glare film precursor on the transfer surface of the transfer film and curing it, then peeling the cured anti-glare film from the transfer film (coating) Method); After laminating the uncured and deformable anti-glare film precursor (film-like precursor) and the film for transfer, after the above-mentioned precursor is hardened, the method of peeling the hardened anti-glare film from the film for transfer (Lamination method) etc. As the anti-glare film precursor, a thermoplastic resin in a molten state or an uncured curable resin (or a curable composition containing a curable resin) and the like can be exemplified. Among these methods, the lamination method is preferred in terms of productivity and the like.

In the lamination method, the anti-glare film is preferably a laminated film of a base layer and an anti-glare layer formed on one surface of the base layer and formed of a cured product of a curable composition containing a photo-curable resin. In the lamination method for manufacturing such a laminated film, first, by coating and drying a curable composition containing a photocurable resin on one side of the base material layer, an anti-glare film precursor can also be prepared.

The above-mentioned curable composition may contain a solvent. The solvent can be selected according to the type and solubility of the photocurable resin, as long as it is a solvent that can at least uniformly dissolve the solid component (for example: photocurable resin, polymer component, photopolymerization initiator, other additives) . As such a solvent, for example, ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexyl) Alkanes, etc.), alicyclic hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated hydrocarbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, Ethyl acetate, butyl acetate, etc.), water, alcohols (ethanol, isopropanol, butanol, cyclohexanol, etc.), celluloids [methylcellulose, ethylcellulose, propylene glycol monomethyl Ether (1-methoxy-2-propanol), etc.], Cellulose acetates, sulfonylates (dimethyl sulfoxide, etc.), amides (dimethylformamide, dimethyl ethyl) Amides, etc.) etc. In addition, the solvent may be a mixed solvent. Among these solvents, aliphatic ketones such as methyl ethyl ketone and methyl isobutyl ketone are preferred.

The concentration of the solute (photocurable resin, polymer component, reaction initiator, other additives) in the composition can be selected within a range that does not impair castability or coatability, for example, 1 to 80% by mass, which is It is preferably 10 to 70% by mass, and more preferably about 15 to 50% by mass (particularly 20 to 30% by mass).

Examples of the coating method include conventional methods, for example, roll coating method, air knife coating method, blade coating method, bar coating method, reverse coating method, bar coating method, and notch Wheel coating method, dip-extrusion coating method, die coating method, gravure coating method, micro gravure coating method, screen coating method, dipping method, spray method, spin coating method, etc. Among these methods, a general bar coating method or a gravure coating method is used. Furthermore, the coating liquid can be applied as many times as necessary.

After the above composition is cast or coated, it may be dried to evaporate the solvent. Drying may be natural drying, but it may also be based on the boiling point of the solvent, for example, at 30 to 200°C (for example, 30 to 100°C), preferably 40 to 120°C, and more preferably 50 to 90°C (especially 60 to 85 ℃) Dry at around temperature.

The anti-glare film precursor obtained in this way is laminated with the transfer film using a conventional laminator such as a laminator. In detail, by laminating the anti-glare film precursor and the transfer film in such a manner that the coating layer of the precursor formed from the curable composition contacts the transfer surface of the transfer film, the anti-glare film is obtained. A laminate in which the glare film precursor and the transfer film are integrated.

After hardening the obtained laminate by light irradiation, the transfer film is peeled from the laminate to obtain an anti-glare film. The light irradiation can be selected according to the type of photocurable resin, etc. Usually, ultraviolet rays, electron beams, etc. can be used. The general light source is usually an ultraviolet irradiation device.

As a light source, for example, in the case of ultraviolet rays, Deep UV lamps, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, halogen lamps, laser light sources (light sources such as helium-cadmium lasers, excimer lasers, etc.), and the like can be used. The amount of irradiated light (irradiated energy in terms of accumulated light amount) varies depending on the thickness of the coating film, for example, 10 to 10000 mJ/cm ² , preferably 20 to 5000 mJ/cm ² , and more preferably 30 to 3000 mJ/cm ² or so. If necessary, light irradiation can also be performed in an inert gas environment.

[Display device] Since the anti-glare film of the present invention can have both anti-glare properties and scratch resistance, it can be used in various display devices, such as liquid crystal display devices (LCDs), organic EL displays, etc., especially as an additional touch input using a finger or a pen The display device of the control panel, especially the LCD or organic EL display with a high-resolution touch panel is more useful.

In detail, the LCD may be a reflective LCD that illuminates a display unit equipped with a liquid crystal unit using external light, or a transmissive LCD equipped with a backlight unit that illuminates the display unit. In the reflective LCD, the incident light from the outside can be captured through the display unit, and the penetrating light penetrating through the display unit can be reflected by the reflective member to illuminate the display unit. In the reflective LCD, the anti-glare film of the present invention can be disposed in the optical path in front of the reflective member. For example, the anti-glare film of the present invention can be disposed or laminated on the front surface of the display unit (front side of the viewing side), etc., and in particular, can also be disposed on the front surface of the LCD with the collimated backlight unit and without the sheet.

In a transmissive LCD, the backlight unit may also be provided to allow light from a light source (a tube light source such as a cold cathode tube, a point light source such as a light-emitting diode, etc.) to enter from one side and exit from the front exit surface Light guide plate (for example, a light guide plate with a wedge-shaped cross section). In addition, if necessary, it is also possible to arrange a lute sheet on the front side of the light guide plate. Furthermore, in general, a reflecting member for reflecting light from the light source toward the exit surface side is provided on the back of the light guide plate. In such a transmissive LCD, the anti-glare film of the present invention can usually be arranged in the optical path in front of the light source. For example, the anti-glare film can be arranged or laminated on the front surface of the display unit.

In an organic EL display, an organic EL system constitutes a light-emitting element for each pixel. The light-emitting element is usually composed of a negative electrode such as metal/electron injection layer/electron transport layer/light emitting layer/hole transport layer/hole injection layer/ITO and other positive electrodes It is formed by substrates such as electrodes/glass plates or transparent plastic plates. In an organic EL display, the anti-glare film of the present invention can also be arranged in the optical path.

In addition, the anti-glare film of the present invention can be used as a protective film for the aftermarket to prevent scratches on LCDs or organic EL displays with touch panels. [Example]

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. The details of the raw materials and films used in the examples and comparative examples and the preparation method of the coating liquid are as follows. The anti-glare films obtained in the examples and comparative examples were evaluated according to the following methods.

[raw material] Acrylic resin with a polymerizable group: a compound obtained by adding 3,4-epoxycyclohexenyl methyl acrylate to a part of the carboxyl group of (meth)acrylic acid-(meth)acrylate copolymer, Daicel Co., Ltd. "Cyclomer P (ACA) 320M" manufactured by the company, solid content 40% by mass Cellulose acetate propionate: "CAP-482-20" manufactured by Eastman, acetylation degree=2.5%, propylation degree=46%, polystyrene conversion number average molecular weight 75000 Multifunctional amine acrylate: 15 functional amine acrylate, theoretical molecular weight 2300, "U-15HA" manufactured by Shin Nakamura Chemical Industry Co., Ltd. Dipentaerythritol hexaacrylate: "DPHA" manufactured by Diacel Allnex Co., Ltd. Neopentaerythritol tri and tetraacrylate: "ARONIX M-305" manufactured by East Asia Synthetic Co., Ltd. Fluorine-containing UV-reactive surface modifier: "MEGAFAC RS-75" manufactured by DIC Corporation Silicone acrylate: "EBECRYL 1360" manufactured by Daicel Allnex Co., Ltd. Amino acrylate containing fluorine and ester: "EBECRYL 8110" manufactured by Daicel Allnex Co., Ltd. Photopolymerization initiator: "Omnirad 184" manufactured by IGM Resins Organic-inorganic hybrid coating liquid: "Acier E-50PGR" manufactured by Nidek Corporation.

[membrane] PET film: polyethylene terephthalate film, "O321" manufactured by Mitsubishi Resin Co., Ltd., thickness 125 μm Transfer film A: "PF11-007F" manufactured by Daicel Co., Ltd., which has a transfer layer with uneven shape on the transparent substrate (Ra 0.08 μm, RSm 14 μm, Rt 0.5 μm, Rsk 0.3 on the transfer surface) , Water contact angle 97 °) laminated film.

[Coating liquid for forming transfer film] (Coating solution 1) 43 parts by mass of acrylic resin having a polymerizable group, 5 parts by mass of cellulose acetate propionate, 78 parts by mass of polyfunctional amine acrylate, 1 part by mass of a UV-containing surface modifier containing a fluorine group, and photopolymerization start 2 parts by mass of the agent was dissolved in a mixed solvent of 185 parts by mass of methyl ethyl ketone (MEK) and 30 parts by mass of 1-butanol to prepare a coating solution 1.

(Coating solution 2) Dissolve 50 parts by mass of acrylic resin having a polymerizable group, 4 parts by mass of cellulose acetate propionate, 76 parts by mass of polyfunctional acrylate acrylate, 1 part by mass of polysiloxane acrylate, and 2 parts by mass of photopolymerization initiator A mixed solvent of 185 parts by mass of methyl ethyl ketone and 30 parts by mass of 1-butanol was used to prepare coating solution 2.

[Coating liquid for forming anti-glare layer] (Coating solution 3) 90 parts by mass of dipentaerythritol hexaacrylate, 10 parts by mass of neopentaerythritol tri and tetraacrylate, 2 parts by mass of cellulose acetate propionate, 0.5 parts by mass of amine acrylate containing fluorine and ester, photopolymerized 2 parts by mass of the initiator was dissolved in a mixed solvent of 170 parts by mass of methyl ethyl ketone and 170 parts by mass of methyl isobutyl ketone to prepare coating liquid 3.

[Thickness of anti-glare layer] Using an optical film thickness meter, 10 arbitrary locations were measured, and the average value was calculated.

[Haze] According to JIS K7163, a haze meter (manufactured by Nippon Denshoku Co., Ltd., trade name "NDH-5000W") was used, and the surface of the glare layer was placed and measured on the light receiver side.

[Full light transmittance] Measured using a haze meter (manufactured by Nippon Denshoku Co., Ltd., trade name "NDH-5000W") according to JIS K7361.

[60° glossiness] According to JIS Z8741, a gloss meter ("Poly gloss KT-GL0030" manufactured by TQC) was used to measure at an angle of 60°.

[Surface shape] According to JIS B0601, a non-contact surface-layer cross-sectional shape measurement system ["VertScan2.0" manufactured by Ryoka Systems Co., Ltd.] was used to measure the unevenness of the surface of the anti-glare layer using a 50x objective lens with a field of view of 253 μm × 189 μm. A curve is obtained, and the arithmetic average roughness Ra, the average length of the roughness curve elements RSm, the maximum profile height Rt of the roughness curve, and the skewness Rsk are respectively obtained based on the curve.

[Anti-glare] Irradiate the laminate with a bare fluorescent lamp without a light shield, visually confirm the glare of the regular reflection light, and evaluate according to the following criteria ◎: No glare 〇: Slight glare ×: Glare is felt.

[Steel wool (SW) resistance] Use a steel wool durability testing machine equipped with a steel rod with a diameter of 1 cm covered by steel wool #0000, change the load at room temperature (20~25°C), and rub the anti-glare layer at a speed of 50 mm/sec at a distance of 5 cm After 100 times on the surface, visually confirm the maximum load without scratches.

Example 1 (Preparation of anti-glare film) An organic-inorganic mixed coating liquid as a coating liquid for forming an anti-glare layer on a PET film was applied using a wire bar coater, and dried in an oven at 80°C for 1 minute To form a coating (transferred layer) with a dry thickness of 6 μm. Next, the film A for transfer was used, the coating surface was arrange|positioned so that it might contact with the transfer surface of the film A for transfer, and it passed through the laminator (made by Toshiba Machine Co., Ltd.), and the laminated body was produced. Furthermore, on the uncured coating side, a high-pressure mercury lamp (manufactured by EYE GRAPHICS Co., Ltd.) was irradiated with ultraviolet light with a cumulative light amount of 400 mJ/cm ² under a nitrogen atmosphere, and then the transfer film A was peeled off from the laminate to obtain Anti-glare film.

Comparative example 1 As the anti-glare film, the film A for transfer was used.

Example 2 (Production of film B for transfer) The coating liquid 1 was applied to the PET film using a wire bar coater, dried in an oven at 80°C for 1 minute, and a coating (transfer layer) was formed so that the dry thickness became 7 μm. The Ra of the transfer surface is 0.19 μm, RSm is 24 μm, Rt is 1.0 μm, Rsk is 0.6, and the water contact angle is 102°.

(Production of anti-glare film) The coating liquid 3 was applied to the PET film using a wire bar coater, dried in an oven at 80°C for 1 minute, and a coating (transferred layer) was formed so that the dry thickness became 6 μm. Next, the transfer film B was used instead of the transfer film A, and the anti-glare film was obtained in the same manner as in Example 1 except for this.

Comparative example 2 As the anti-glare film, the film B for transfer was used.

Example 3 (Production of Film C for Transfer) The coating solution 2 was applied to the PET film using a wire bar coater, dried in an oven at 80°C for 1 minute, and a coating (transfer layer) was formed so that the dry thickness became 10 μm. The Ra of the transfer surface is 0.33 μm, RSm is 29 μm, Rt is 1.8 μm, Rsk is 0.3, and the water contact angle is 102°.

(Production of anti-glare film) The coating liquid 3 was applied to the PET film using a wire bar coater, dried in an oven at 80°C for 1 minute, and a coating (transferred layer) was formed so that the dry thickness became 7 μm. Next, an anti-glare film was obtained in the same manner as in Example 1 except that the film C for transfer was used instead of the film A for transfer.

Comparative Example 3 As the anti-glare film, the film C for transfer was used.

Table 1 shows the evaluation results of the anti-glare films obtained in Examples and Comparative Examples.

[Table 1]

From the results in Table 1, it can be seen that the anti-glare film of the embodiment can have both anti-glare properties and scratch resistance. On the other hand, the anti-glare film of the comparative example cannot improve the scratch resistance. [Industry availability]

The anti-glare film of the present invention can be used as an anti-glare film for various display devices, such as liquid crystal display (LCD), cathode tube display, organic or inorganic electroluminescence (EL) display, field emission display (FED), surface electric field Display devices such as monitors (SED) and rear projection TV monitors, especially in terms of excellent scratch resistance, are suitable for car navigation monitors, game machines, smartphones, personal computers (PC) (tablet PC, notebook or laptop) Pointing devices for computers such as upper PCs, desktop PCs, etc., handwriting boards, and display devices with touch panels such as TVs.

no

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Claims (10)

An anti-glare film includes an anti-glare layer having a surface shape with a skewness Rsk less than 0 and an average length RSm of roughness curve elements of 1 to 50 μm. The anti-glare film according to claim 1, wherein the anti-glare layer does not contain particles having a particle diameter of 3 μm or more. The anti-glare film according to claim 1 or 2, wherein the anti-glare layer does not contain particles. The anti-glare film according to claim 1 or 2 has a haze of 1 to 60%. The anti-glare film according to claim 1 or 2, wherein the 60° gloss of the surface of the anti-glare layer is 1 to 70%. The antiglare film according to claim 1 or 2, wherein the antiglare layer is a cured product of a curable composition containing a photocurable resin. A method for manufacturing an anti-glare film according to any one of claims 1 to 6, which includes a transfer step in which the transfer surface of the transfer film is used as a forming die and is applied to the precursor of the anti-glare film The transfer surface has a concave-convex shape that is the reverse shape of the transfer surface. The manufacturing method according to claim 7, further comprising a transfer film forming step, which is phase-separated by the decomposition of the wet spinner to form a transfer surface. A display device provided with the anti-glare film according to any one of claims 1 to 6. The display device according to claim 9, which is a liquid crystal display device with an touch panel or an organic EL display.