JP6824939B2 - Anti-glare film and its manufacturing method and application - Google Patents

Description

The present invention relates to an antiglare film having excellent scratch resistance, which is suitable for preventing reflection of an external light source on the display surface of various display devices and is less likely to be scratched by friction, and a method and application thereof.

The antiglare film is used to prevent glare and improve visibility while preventing the reflection of the outside view on the display surface of an image display device such as a liquid crystal display (LCD) or an organic electroluminescence (EL) display. Widely used as a film. The antiglare film exhibits antiglare properties by forming an uneven shape on the surface and scattering and reflecting external light, but hard coat properties and scratch resistance are also required depending on the application. In the antiglare film, as a method for forming the antiglare layer having a hard coat property, a method of roughening the surface of the antiglare layer by a physical method (physical roughening method), adding particles to the binder resin. There are known a method of forming irregularities on the surface of the antiglare layer (particle addition method), a method of forming irregularities on the surface of the antiglare layer by phase separation of resin components (phase separation method), and the like.

As an antiglare film obtained by a physical roughening method, Japanese Patent Application Laid-Open No. 2014-47300 (Patent Document 1) states that the film is formed by transfer from a mold having irregularities and has an arithmetic average roughness Ra of 0.005. An optical member having a concavo-convex shape of ~ 2.5 μm is disclosed.

As the antiglare film obtained by the particle addition method, Japanese Patent Application Laid-Open No. 2014-16602 (Patent Document 2) describes silica fine particles having an average primary particle diameter of 1 to 100 nm, organic fine particles having an average particle diameter of 0.5 to 5 μm, and a binder. Disclosed is an antiglare film having an antiglare layer in which the average spacing Sm of the unevenness is 50 μm <Sm <600 μm and the arithmetic average roughness Ra of the unevenness is 0.02 μm <Ra <0.25 μm. There is. Further, Japanese Patent Application Laid-Open No. 2012-98734 (Patent Document 3) contains fine particles having an average particle diameter of 1 to 20 μm and a curable resin, and has an uneven shape having an average roughness Rz of 0.3 to 1.8 μm. An antiglare film having a glare layer is disclosed.

As an antiglare film obtained by the phase separation method, Japanese Patent Application Laid-Open No. 2009-276772 (Patent Document 4) provides an antiglare layer having an uneven structure on the surface formed by phase separation by spinodal decomposition from a liquid phase. Disclosed is an antiglare film that includes, isotropically transmits and scatters incident light, has a scattering angle of 0.1 to 10 ° and has a haze of 20 to 50%, which indicates a maximum value of scattered light intensity. ing. Further, Japanese Patent Application Laid-Open No. 2014-85371 (Patent Document 5) has an elongated convex portion having a co-continuous phase structure formed by phase separation of a plurality of resin components on the surface, and has a 60 ° gloss. An antiglare film containing an antiglare layer having a haze of 30 or more and a haze of 10 to 40% is disclosed. Further, Japanese Patent Application Laid-Open No. 2014-92657 (Patent Document 6) describes a surface film for a multi-touch display in which irregularities are formed on the surface due to a phase-separated structure of a plurality of polymers, and the haze is 15 to 50%. A surface film having a three-dimensional arithmetic mean roughness Sa of the surface of 0.15 to 1 μm is disclosed.

However, although these antiglare layers can exhibit antiglare properties, they do not have sufficient scratch resistance. Specifically, when the surface of the antiglare film is rubbed, the convex portion of the surface is rubbed. Therefore, depending on the conditions such as the material to be rubbed, the speed, the length, the load, and the number of times of friction, the uneven shape is worn and the particles are worn. In the antiglare layer obtained by the addition method, particles may fall off.

JP-A-2014-47300 (Claim 7) JP-A-2014-16602 (Claim 1, paragraphs [0035] [0049]) JP 2012-98734 (Claim 1, paragraphs [0027] [0035]) JP-A-2009-276772 (Claim 1, paragraph [0076]) JP-A-2014-85371 (Claim 1, paragraphs [095] [0102]) JP-A-2014-92657 (Claim 1)

Therefore, an object of the present invention is to provide an antiglare film capable of achieving both antiglare and scratch resistance, and a method and application thereof.

As a result of diligent studies to achieve the above object, the present inventor adjusts the surface shape of the antiglare layer to a shape in which the skewness Rsk is less than 0 and the average length RSm of the roughness curve element is 1 to 50 μm. The present invention has been completed by finding that both anti-glare property and scratch resistance can be achieved.

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

The present invention comprises a transfer step of forming a concave-convex shape in which the transfer surface is inverted on the transfer surface of the antiglare film precursor by using the transfer surface of the transfer film as a molding die. The manufacturing method is also included. This production method may further include a transfer film forming step of forming a transfer surface by phase separation by wet spinodal decomposition.

The present invention also includes a display device provided with the antiglare film. This display device may be a liquid crystal display device with a touch panel or an organic EL display.

In the present invention, since the surface shape of the antiglare layer is adjusted to be less than skewness Rsk0 and the average length of the roughness curve element is RSm1 to 50 μm, both antiglare and scratch resistance can be achieved at the same time.

[Anti-glare layer]
The antiglare film of the present invention includes an antiglare 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 reason why the antiglare layer having such a surface shape can achieve both antiglare and scratch resistance is not clear, but the surface shape satisfying Rsk and RSm has a relatively flat friction surface of the convex portion. It is large and has a shape in which many fine valleys are formed between the convex portions having such a flat friction surface, and even if the friction surface is repeatedly rubbed, it is flat and large, so that wear is suppressed and a large number of small ones are formed. It can be estimated that the anti-glare property is also guaranteed by the valley of.

The skewness Rsk (bias) on the surface of the antiglare layer is an index for evaluating the symmetry of the height distribution, but it may be less than 0, for example, -10 or more and less than 0, preferably -5 to -0.01. , More preferably about −1 to −0.1 (particularly −0.5 to −0.2). When Rsk becomes 0 or more, the scratch resistance is lowered.

The average length RSm of the roughness curve element on the surface of the antiglare 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 (particularly 10 to 25 μm). In applications where a high degree of scratch resistance is required, RSm may be about 10 to 30 μm (particularly 20 to 25 μm). If RSm is too small, it may be difficult to control the size of the unevenness, and conversely, if it is too large, the antiglare property may be lowered.

The arithmetic mean roughness Ra of the surface of the antiglare 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 0.04 to 0.6 μm (. In particular, it is about 0.05 to 0.5 μm). In applications where a high degree of scratch resistance is required, Ra may be about 0.2 to 1 μm (particularly 0.25 to 0.5 μm). If Ra is too small, the antiglare property may be lowered, and if it is too large, the scratch resistance may be lowered.

The maximum cross-sectional height Rt of the roughness curve of the surface of the antiglare layer is, for example, 0.1 to 3 μm, preferably 0.5 to 2.5 μm, and more preferably 1 to 2 μm (particularly 1.5 to 1.8 μm). Is. If Rt is too small, the antiglare property may be lowered, and if it is too large, the scratch resistance may be lowered.

Within the scope of the present specification and patent claims, the skewness Rsk, the average length RSm of the roughness curve element, the arithmetic average roughness Ra and the maximum cross-sectional height Rt of the roughness curve are determined by the non-contact surface / layer cross-sectional shape measurement system [ It can be obtained based on the curve obtained by measuring the uneven shape of the antiglare layer surface using "VertScan 2.0" manufactured by Ryoka System Co., Ltd., and the details will be described in Examples described later. It can be measured by the method of.

The 60 ° gloss on the surface of the antiglare layer is, for example, 1 to 70% (for example, 5 to 65%), preferably 2 to 60%, and more preferably 3 to 55% (particularly 5 to 50%). In applications where a high degree of scratch resistance is required, the 60 ° gloss may be about 5 to 30% (particularly 10 to 20%). If the 60 ° gloss is too small, the visibility may be lowered, and if it is too large, the antiglare property may be lowered.

In the present specification and claims, 60 ° gloss can be measured using a gloss meter (“Polygloss KT-GL0030” manufactured by TQC) in accordance with JIS K8741.

The antiglare layer may have the above-mentioned characteristics and the characteristics of the antiglare film described later, and the material is not particularly limited. The material constituting the antiglare layer can be selected from various transparent organic materials (thermoplastic resin, thermosetting resin, photocurable resin, etc.) and inorganic materials (glass, ceramics, metal, etc.), but is scratch resistant. From the viewpoint of property and productivity, a cured product of a curable composition containing a curable resin is preferable.

(Curable resin)
The curable resin may be either a thermosetting resin or a photocurable resin, but a photocurable resin is preferable from the viewpoint of productivity and the like. A photocurable resin (photocurable resin precursor component) is a compound that can be cured or crosslinked by active energy rays such as ultraviolet rays and electron beams to form a resin, and is a fluorine-free photocurable resin and a fluorine-containing photocurable resin. It can be roughly divided into sex resins.

Fluorine-free photocurable resins include monomers and oligomers (or resins, especially low molecular weight resins).

Examples of the monomer include a monofunctional monomer [a (meth) acrylic monomer such as (meth) acrylic acid ester, a vinyl monomer such as vinylpyrrolidone, an isobornyl (meth) acrylate, and an adamantyl ( (Meta) acrylate having a bridging ring-type hydrocarbon group such as meta) acrylate] Bifunctional monomer [ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butanediol di (meth) acrylate , Neopentyl glycol di (meth) acrylate, alkylene glycol di (meth) acrylate such as hexanediol di (meth) acrylate; diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyoxytetramethylene glycol di ( (Poly) oxyalkylene glycol di (meth) acrylates such as meta) acrylates; di (meth) acrylates having bridging ring hydrocarbon groups such as tricyclodecanedimethanol di (meth) acrylates and adamantandi (meth) acrylates] , Trifunctional or higher functional monomer [glycerin tri (meth) acrylate, trimethyl propantri (meth) acrylate, trimethylol ethanetri (meth) acrylate, tetramethylol methanetri (meth) acrylate, pentaerythritol tri ( Meta) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) 3 to 6 functional monomers such as meta) acrylate and dipentaerythritol hexa (meth) acrylate] and the like can be exemplified. Of these, polyfunctional (meth) acrylates having at least two (meth) acryloyl groups are widely used.

Examples of the oligomer or resin include (meth) acrylate of a bisphenol A-alkylene oxide adduct, epoxy (meth) acrylate [polyfunctional epoxy (meth) acrylate having two or more (meth) acryloyl groups], and polyester (meth). ) Acrylate [polyfunctional polyester (meth) acrylate having two or more (meth) acryloyl groups], urethane (meth) acrylate [polyfunctional urethane (meth) acrylate having two or more (meth) acryloyl groups], silicone Examples thereof include (meth) acrylate [polyfunctional silicone (meth) acrylate having two or more (meth) acryloyl groups] and (meth) acrylic polymer having a polymerizable group.

These fluorine-free photocurable resins can be used alone or in combination of two or more. Of these, from the viewpoint of scratch resistance, a polyfunctional monomer having two or more functionalities is preferable, a polyfunctional monomer having three or more functionalities is more preferable, and a polyfunctional monomer having five or more functionalities is particularly preferable. preferable.

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

The fluorine-free photocurable resin is a polyfunctional monomer having 4 or less functionalities (particularly 3 to 4 functional monomers) and a polyfunctional monomer having 5 or more functionalities (particularly 5 to 8 functional single amounts). It may be a combination with the body). When both are combined, the mass ratio of the polyfunctional monomer having four or less functionalities and the polyfunctional monomer having five or more functionalities is the former / the latter = 90/10 to 1/99, preferably 50/50 to 50. It is about 2/98, more preferably about 30/70 to 3/97 (particularly 20/80 to 5/95).

The fluorine-containing photocurable resin may be a fluoride of a monomer or an oligomer which is the fluorine-free photocurable resin. Examples of the fluorine-containing photocurable resin include alkyl fluoride (meth) acrylate [for example, perfluorooctyl ethyl (meth) acrylate, trifluoroethyl (meth) acrylate, etc.], and fluoride (poly) oxyalkylene glycol di (. Meta) acrylate [for example, fluoroethylene glycol di (meth) acrylate, fluoropolyethylene glycol di (meth) acrylate, fluoropropylene glycol di (meth) acrylate, etc.], fluorine-containing epoxy (meth) acrylate, fluorine-containing urethane (meth) acrylate. Etc. can be exemplified. 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.
Of these, fluoropolyether compounds having a (meth) acryloyl group and fluorine-containing urethane (meth) acrylates are preferable, and fluorine and ester-containing urethane (meth) acrylates are particularly preferable.

The photocurable resin preferably contains at least a fluorine-free photocurable resin, and a combination of a fluorine-free photocurable resin and a fluorine-containing photocurable resin is particularly preferable. The proportion of the fluorine-free photocurable resin 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 the fluorine-free photocurable resin and the fluorine-containing photocurable resin are combined, the ratio of the fluorine-containing photocurable resin is, for example, 0.1 to 10 parts by mass with respect to 100 parts by mass of the fluorine-free photocurable resin. Parts, preferably 0.2 to 8 parts by mass, more preferably 0.3 to 6 parts by mass (particularly 0.4 to 5 parts by mass). If the proportion of the fluorine-containing photocurable resin is too small, the surface modification effect may be lowered, and if it is too large, the scratch resistance may be lowered.

(Polymer component)
The curable composition may further contain a polymer component in addition to the curable resin (particularly a photocurable resin) from the viewpoint of improving scratch resistance. As the polymer component, a thermoplastic resin is usually used. The thermoplastic resin may have high transparency, for example, a styrene resin, a (meth) acrylic polymer, an organic acid vinyl ester polymer, a vinyl ether polymer, a halogen-containing resin, and a polyolefin (alicyclic polyolefin). (Including), polycarbonate, polyester, polyamide, thermoplastic polyurethane, polysulfone resin (polyethersulfone, polysulfone, etc.), polyphenylene ether resin (polymer of 2,6-xylenol, etc.), cellulose derivative (cellulose esters, cellulose, etc.) Carbamates, cellulose ethers, etc.), silicone resins (polydimethylsiloxane, polymethylphenylsiloxane, etc.), fluororesins, rubbers or elastomers (diene rubbers such as polybutadiene, polyisoprene, styrene-butadiene copolymers, acrylonitrile-butadiene) (Copolymer, acrylic rubber, urethane rubber, silicone rubber, etc.) can be exemplified. These thermoplastic resins can be used alone or in combination of two or more.

Among these polymer components, styrene-based resins, (meth) acrylic-based polymers, alicyclic polyolefins, polyesters, and cellulose derivatives (cellulosic esters, etc.) because they are non-crystalline and soluble in organic solvents. Etc. are preferable, and cellulose esters are particularly preferable.

Examples of cellulose esters include aliphatic organic acid esters (cellulose acetates such as cellulose diacetate and cellulose triacetate; C _1-6 such as cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate). Examples include aliphatic carboxylic acid esters), aromatic organic acid esters (C _7-12 aromatic carboxylic acid esters such as cellulose phthalate and cellulose benzoate), and inorganic acid esters (for example, cellulose phosphate, cellulose sulfate, etc.). It may be a mixed acid ester such as acetic acid / nitrate cellulose ester. These cellulose esters can be used alone or in combination of two or more. Of these, cellulose C _2-4 acylate such as cellulose diacetate, cellulose triacetate, cellulose acetate propionate, and cellulose acetate butyrate is preferable, and cellulose acetate C _3-4 acylate such as cellulose acetate propionate is particularly preferable.

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

(Filler)
The curable composition may further contain fillers (particles) in order to balance antiglare and scratch resistance. Examples of the filler include inorganic particles such as silica particles, titania particles, zirconia particles, alumina particles, zinc oxide particles, tin oxide particles, antimony oxide particles, and tin-doped indium oxide (ITO) particles; crosslinked (meth) acrylic weight. It may contain organic particles such as coalesced particles and crosslinked styrene resin particles. These fillers can be used alone or in combination of two or more.

Of these fillers, silica particles are preferable because they can easily achieve both anti-glare and scratch resistance. As the silica particles, solid silica particles are preferable from the viewpoint of improving the transparency of the antiglare film.

The shape of the filler may be an anisotropic shape, but an isotropic shape is preferable, and a spherical shape is particularly preferable. 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 5 to 100 nm (particularly 10 to 30 nm). If the average particle size of the filler is too large, the scratch resistance may decrease.

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

The filler may be in a form modified with the curable resin by reacting with the curable resin in advance.

In the present invention, from the viewpoint of scratch resistance, the antiglare layer preferably contains substantially no filler (particles) having a particle size of 3 μm or more, and particularly preferably does not contain any filler (particles). As described above, the antiglare layer preferably contains particles, and particularly preferably contains a filler having a particle size of less than 3 μm, from the viewpoint of balancing antiglare and scratch resistance. Further, when a high degree of scratch resistance is required, the antiglare layer preferably contains substantially no filler itself, and particularly preferably no filler, regardless of the particle size.

(Other ingredients)
The curable composition may further contain a curing agent depending on the type of the curable resin. For example, the thermosetting resin may contain a curing agent such as amines and polyvalent carboxylic acids, and the photocurable resin may contain a photopolymerization initiator. Examples of the photopolymerization initiator include conventional components such as acetophenones or propiophenones, benzyls, benzoins, benzophenones, thioxanthones, and acylphosphine oxides. The ratio of the curing agent such as the photopolymerization initiator 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 with respect to 100 parts by mass of the curable resin. Is.

The curable composition may further contain a curing accelerator. For example, the photocurable resin may contain a photocuring accelerator, for example, a tertiary amine (such as dialkylaminobenzoic acid ester), a phosphine-based photopolymerization accelerator, or the like.

Curable compositions include conventional additives such as silane coupling agents (eg silane coupling agents having a thiol group), leveling agents, stabilizers (antioxidants, UV absorbers, etc.), surfactants. , Water-soluble polymer, filler, cross-linking agent, coupling agent, colorant, flame retardant, lubricant, wax, preservative, viscosity regulator, thickener, defoamer and the like may be contained. The ratio of the additive can be selected from the range of, for example, about 0.01 to 100 parts by mass with respect 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). Is.

(Thickness of antiglare layer)
The thickness (average thickness) of the antiglare layer is, for example, about 1 to 20 μm, preferably 2 to 15 μm, and more preferably 3 to 10 μm (particularly 5 to 8 μm). In the present specification and claims, the average thickness of each layer can be obtained by measuring arbitrary 10 points using an optical film thickness meter and calculating an average value.

[Base layer]
The antiglare film of the present invention may be formed of the antiglare layer alone, or may be formed of a base material layer and an antiglare layer formed on at least one surface of the base material layer. .. Of these, from the viewpoint of handleability, mechanical properties, productivity, etc., it is preferable to laminate the antiglare layer on one surface (only one surface) of the base material layer.

The base material layer may be made of a transparent material and can be selected according to the intended use, and may be an inorganic material such as glass, but an organic material is widely used from the viewpoint of strength and moldability. Examples of the organic material include cellulose derivatives, polyesters, polyamides, polyimides, polycarbonates, and (meth) acrylic polymers. Of these, cellulose esters, polyesters, polycarbonates and the like are widely used, with polyesters and polycarbonates being preferred.

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

Of these, poly C _2-4 alkylene-arylate such as PET and PEN and bisphenol A type polycarbonate are preferable from the viewpoint of excellent balance of mechanical properties and transparency, and poly such as PET is preferable from the viewpoint of versatility. _C2-3 alkylene-arylate is particularly preferred.

The substrate layer may also contain the conventional additives exemplified in the section on antiglare layers. The proportion of additives is the same as that of the antiglare layer.

The base material layer may be a uniaxial or biaxially stretched film, but may be an unstretched film because of its low birefringence and excellent optical isotropic properties.

The base material layer may be surface-treated (for example, corona discharge treatment, flame treatment, plasma treatment, ozone or ultraviolet irradiation treatment, etc.), or may 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 antiglare film of the present invention is excellent in transparency and visibility. The haze of the antiglare film of the present invention is, for example, 1 to 60%, preferably 5 to 55%, and more preferably about 10 to 50%. Further, the haze of the antiglare film of the present invention may be a relatively high haze from the viewpoint of improving the antiglare property, for example, 10 to 60%, preferably 30 to 55%, still more preferably 40 to 50. It is about%. If the haze is too low, the antiglare property may be lowered, and if it is too high, the visibility may be lowered.

In the present specification and claims, haze can be measured using a haze meter (“NDH-5000W” manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with JIS K7163.

The total light transmittance of the antiglare film of the present invention is, for example, 70% or more (for example, 70 to 100%), preferably 80 to 99%, and more preferably 85 to 98% (particularly 88 to 95%). If the total light transmittance is too low, the transparency may decrease.

In the present specification and claims, the total light transmittance can be measured using a haze meter (“NDH-5000W” manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with JIS K7361.

In addition to the antiglare layer and the base material layer, the antiglare film of the present invention may be combined with an adhesive layer, a low refractive index layer, an antireflection layer and the like as conventional functional layers.

The thickness (average thickness) of the antiglare 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 antiglare film]
The method for producing the antiglare film of the present invention is not particularly limited as long as it can form an uneven shape having the above-mentioned Rsk and RSm on the surface of the antiglare layer, and a conventional method can be used. Conventional methods include, for example, a method of forming an uneven shape using particles (for example, a method of forming a convex portion by following the shape of the particles), and a curable composition containing a phase-separable resin component. A method of phase-separating the resin components and then curing, a method of transferring using a mold having an uneven shape on the surface, a method of forming an uneven shape by cutting (for example, cutting using a laser or the like), polishing. (For example, sandblasting method, bead shot method, etc.), a method of forming an uneven shape by etching, and the like can be mentioned.

Of these, from the viewpoint of productivity and the like, the method of transferring using a mold having an uneven shape on the surface is preferable, and the transfer surface of the transfer film is used as a molding mold, and the transfer surface of the antiglare film precursor is used as described above. A method including a transfer step of forming a concavo-convex shape in which the transfer surface is inverted is more preferable, and as a pre-step of the transfer step, a transfer film forming step of phase-separating by wet spinodal decomposition to form a transfer surface is further performed. The method including is most preferable.

In the method of utilizing phase separation by wet spinodal decomposition in the transfer film forming step, the concentration is in the process of evaporating or removing the solvent from the liquid phase of the composition containing the phase-separable resin component and the solvent by drying or the like. By causing phase separation by spinodal decomposition (wet spinodal decomposition) with the concentration of, a surface shape (concavo-convex shape due to the phase-separated structure) may be formed in which the desired uneven shape on the surface of the antiglare layer is inverted. .. Examples of the combination of phase-separable resin components include a combination of the photocurable resins exemplified in the section of the antiglare layer, and a polymer component (heat) exemplified by the photocurable resin resin and the antiglare layer. It may be a combination with a (plastic resin) or a combination of the polymer components, and may be, for example, a (meth) acrylic polymer (for example, polymethyl methacrylate, a (meth) acrylic polymer having a polymerizable group). Etc.) and cellulose esters (such as cellulose acetate C _3-4 acylate such as cellulose acetate propionate) and / or urethane (meth) acrylate and the like may be used. Examples of the method using phase separation include JP-A-2007-187746, JP-A-2008-225195, JP-A-2009-267775, JP-A-2011-175601, JP-A-2014-85371, JP-A-2014-92657, JP-A-2014. -98771, JP-A-2016-161859, JP-A-2017-219622, and the like can also be used.

The transfer surface of the transfer film obtained in the transfer film forming step has an Rsk of 0 or more (for example, 0 to 3, preferably 0 to 3) in order to form a desired uneven shape on the surface of the antiglare layer which is the surface to be transferred. The surface shape may be adjusted to 0.1 to 1, more preferably about 0.2 to 0.5) and RSm to be about 1 to 50 μm (particularly about 1 to 30 μm).

On the transfer surface, the water contact angle may be adjusted to 90 ° or more (for example, 90 to 120 °) in order to smoothly peel off the antiglare film obtained by curing. The water contact angle of the transfer surface may be adjusted by using, for example, a fluorine-based compound or a silicone-based compound. In the present specification and claims, the water contact angle can be measured by a conventional method, for example, using an automatic / dynamic contact angle meter.

In the transfer step, as a method of transferring the desired uneven shape to the transfer surface of the antiglare film precursor, an antiglare film precursor in a state capable of following the uneven shape of the transfer surface of the transfer film is used as the transfer surface. The method is not particularly limited as long as it is a method of contacting, solidifying or curing the precursor, and then peeling the solidified or cured antiglare film from the transfer film, and a conventional method is used depending on the type of the antiglare film. It can be selected as appropriate. As a specific method, a method in which a liquid antiglare film precursor is injection-molded in the mold with the transfer film inserted in the mold, and then the solidified antiglare film is peeled off from the transfer film. (In-mold molding method), a method of coating (coating) a liquid antiglare film precursor on the transfer surface of the transfer film, solidifying the film, and then peeling the solidified antiglare film from the transfer film (coating method). , A method of laminating an uncured and deformable antiglare film precursor (film-like precursor) and a transfer film, curing the precursor, and then peeling the cured antiglare film from the transfer film. (Laminating method) or the like may be used. Examples of the antiglare film precursor include a molten thermoplastic resin and an uncured curable resin (or a curable composition containing a curable resin). Of these methods, the laminating method is preferable from the viewpoint of productivity and the like.

In the laminating method, the antiglare film is a laminated film of a base material layer and an antiglare layer which is laminated on one surface of the base material layer and formed of a cured product of a curable composition containing a photocurable resin. Is preferable. In the laminating method for producing such a laminated film, first, a curable composition containing a photocurable resin is applied to one surface of a base material layer and dried to obtain an antiglare film precursor. May be prepared.

The curable composition may contain a solvent. The solvent can be selected according to the type and solubility of the photocurable resin, and is a solvent that can uniformly dissolve at least solids (for example, photocurable resin, polymer component, photopolymerization initiator, and other additives). Good. Examples of such a solvent include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons (such as alicyclic hydrocarbons). Cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), carbon halides (di dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (ethanol, isopropanol, etc.) Butanol, cyclohexanol, etc.), cellosolves [methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl ether (1-methoxy-2-propanol), etc.], cellosolve acetates, sulfoxides (dimethyl sulfoxide, etc.), amides (dimethylformamide, etc.) (Dimethylacetamide, etc.) can be exemplified. Moreover, the solvent may be a mixed solvent. Of these solvents, aliphatic ketones such as methyl ethyl ketone and methyl isobutyl ketone are preferable.

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 ductility, coating property, etc., for example, 1 to 80% by mass, preferably 10. It is about 70% by mass, more preferably 15 to 50% by mass (particularly 20 to 30% by mass).

Conventional methods include, for example, roll coater, air knife coater, blade coater, rod coater, reverse coater, bar coater, comma coater, dip squeeze coater, die coater, gravure coater, micro gravure coater, silk screen coater. Examples include the method, dip method, spray method, and spinner method. Among these methods, the bar coater method and the gravure coater method are widely used. If necessary, the coating liquid may be applied multiple times.

After casting or applying the composition, it may be dried to evaporate the solvent. The drying may be natural drying, but depending on the boiling point of the solvent, for example, 30 to 200 ° C. (for example, 30 to 100 ° C.), preferably 40 to 120 ° C., more preferably 50 to 90 ° C. (particularly 60). It may be dried at a temperature of about (~ 85 ° C.).

The antiglare film precursor thus obtained is laminated with the transfer film using a conventional laminating machine such as a roll laminator. Specifically, the antiglare film precursor and the transfer film are laminated so that the coating layer of the precursor formed of the curable composition and the transfer surface of the transfer film are in contact with each other. A laminate in which the body and the transfer film are integrated is obtained.

The obtained laminate is cured by irradiating with light, and then the transfer film is peeled off from the laminate to obtain an antiglare film. Light irradiation can be selected according to the type of photocurable resin and the like, and usually ultraviolet rays, electron beams and the like can be used. A general-purpose light source is usually an ultraviolet irradiation device.

As the light source, for example, in the case of ultraviolet rays, a Deep UV lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a halogen lamp, a laser light source (a light source such as a helium-cadmium laser or an excimer laser) can be used. Irradiation light amount (irradiation energy of the integrated light quantity) are different depending on the thickness of the coating film, for example, 10 to 10000 mJ / cm ^2, preferably 20~5000mJ / cm ^2, more preferably 30~3000mJ / cm ² approximately. Light irradiation may be carried out in an inert gas atmosphere, if necessary.

[Display device]
Since the antiglare film of the present invention can have both antiglare and scratch resistance, it can be used in various display devices such as a liquid crystal display (LCD) and an organic EL display, and in particular, with a finger or a pen. It is useful as a display device with a touch panel in which input is repeated, particularly as a high-definition LCD with a touch panel or an organic EL display.

Specifically, the LCD may be a reflective LCD that uses external light to illuminate a display unit including a liquid crystal cell, or a transmissive LCD that includes a backlight unit for illuminating the display unit. You may. In the reflective LCD, the incident light from the outside can be taken in through the display unit, and the transmitted light transmitted through the display unit can be reflected by the reflecting member to illuminate the display unit. In the reflective LCD, the antiglare film of the present invention can be arranged in the optical path in front of the reflective member. For example, the antiglare film of the present invention can be arranged or laminated on the front surface of a display unit (front surface on the viewing side), and in particular, is arranged on the front surface of an LCD having a collimating backlight unit and no prism sheet. You may.

In a transmissive LCD, a backlight unit is used to allow light from a light source (a tubular light source such as a cold cathode fluorescent lamp, a point light source such as a light emitting diode, etc.) to enter from one side and emit light from a front emission surface. A light guide plate (for example, a light guide plate having a wedge-shaped cross section) may be provided. Further, if necessary, a prism sheet may be arranged on the front surface side of the light guide plate. Normally, a reflecting member for reflecting the light from the light source toward the emitting surface side is provided on the back surface of the light guide plate. In such a transmissive LCD, the antiglare film of the present invention can usually be arranged in the optical path in front of the light source, and for example, the antiglare film can be arranged or laminated on the front surface of a display unit or the like.

In an organic EL display, an organic EL has a light emitting element configured for each pixel, and this light emitting element is usually a negative electrode such as metal / electron injection layer / electron transport layer / light emitting layer / hole transport layer /. It is formed of a hole injection layer / positive electrode such as ITO / a substrate such as a glass plate or a transparent plastic plate. Also in the organic EL display, the antiglare film of the present invention may be arranged in the optical path.

Further, the antiglare film of the present invention may be used as a protective or protective film for the aftermarket to prevent damage to the LCD with a touch panel or the organic EL display.

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 Examples and Comparative Examples and the method for preparing the coating liquid were as follows, and the antiglare films obtained in Examples and Comparative Examples were evaluated by the following methods.

[material]
Acrylic resin having a polymerizable group: A compound in which 3,4-epoxycyclohexenylmethyl acrylate is added to a part of the carboxyl groups of the (meth) acrylic acid- (meth) acrylic acid ester copolymer, manufactured by Daicel Co., Ltd. "Cyclomer P (ACA) 320M", solid content 40% by mass
Cellulose acetate propionate: Eastman "CAP-482-20", degree of acetylation = 2.5%, degree of propionyl = 46%, polystyrene-equivalent number average molecular weight 75,000
Polyfunctional urethane acrylate: 15-functional urethane acrylate, theoretical molecular weight 2300, "U-15HA" manufactured by Shin Nakamura Chemical Industry Co., Ltd.
Dipentaerythritol hexaacrylate: "DPHA" manufactured by Daicel Ornex Co., Ltd.
Pentaerythritol tri and tetraacrylate: "Aronix M-305" manufactured by Toagosei Co., Ltd.
Fluorine group-containing UV-reactive surface modifier: "Mega Fvck RS-75" manufactured by DIC Corporation
Silicone acrylate: "EBECRYL1360" manufactured by Daicel Ornex Co., Ltd.
Fluorine and ester-containing urethane acrylate: "EBECRYL8110" manufactured by Daicel Ornex Co., Ltd.
Photopolymerization Initiator: "Omnirad 184" manufactured by IGM Resins
Organic-inorganic hybrid coating liquid: "Acier E-50PGR" manufactured by Nidek Co., Ltd.

[the film]
PET film: Polyethylene terephthalate film, "O321" manufactured by Mitsubishi Plastics Co., Ltd., thickness 125 μm
Transfer film A: "PF11-007F" manufactured by Daicel Co., Ltd., a transfer layer having an uneven shape on a transparent base material (Ra 0.08 μm, RS m 14 μm, Rt 0.5 μm, Rsk 0.3, water contact angle 97 on the transfer surface). Laminated film in which °) is laminated.

[Coating liquid for forming a transfer film]
(Coating liquid 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 urethane acrylate, 1 part by mass of a fluorine group-containing ultraviolet reaction type surface modifier, and 2 parts by mass of a photopolymerization initiator. , 185 parts by mass of methyl ethyl ketone (MEK) and 30 parts by mass of 1-butanol were dissolved in a mixed solvent to prepare a coating solution 1.

(Coating liquid 2)
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 urethane acrylate, 1 part by mass of silicone acrylate, 2 parts by mass of photopolymerization initiator, 185 parts by mass of methyl ethyl ketone and 1-by mass. A coating solution 2 was prepared by dissolving in a mixed solvent of 30 parts by mass of butanol.

[Coating liquid for forming an antiglare layer]
(Coating liquid 3)
90 parts by mass of dipentaerythritol hexaacrylate, 10 parts by mass of pentaerythritol tri and tetraacrylate, 2 parts by mass of cellulose acetate propionate, 0.5 parts by mass of fluorine and ester-containing urethane acrylate, 2 parts by mass of photopolymerization initiator, methyl ethyl ketone. The coating liquid 3 was prepared by dissolving in a mixed solvent of 170 parts by mass and 170 parts by mass of methyl isobutyl ketone.

[Thickness of antiglare layer]
Using an optical film thickness meter, any 10 points were measured and the average value was calculated.

[Haze]
In accordance with JIS K7163, a haze meter (manufactured by Nippon Denshoku Co., Ltd., trade name "NDH-5000W") was used to arrange and measure the antiglare layer surface so as to be on the receiver side.

[Total light transmittance]
The measurement was performed using a haze meter (manufactured by Nippon Denshoku Co., Ltd., trade name "NDH-5000W") in accordance with JIS K7361.

[60 ° gloss]
It was measured at an angle of 60 ° using a gloss meter (“Polygloss KT-GL0030” manufactured by TQC) in accordance with JIS Z8741.

[Surface shape]
Compliant with JIS B0601, using a non-contact surface / layer cross-sectional shape measurement system [“VertScan2.0” manufactured by Ryoka System Co., Ltd.], a 50x objective lens, a field of view of 253 μm × 189 μm, and unevenness of the antiglare layer surface Based on the curve obtained by measuring the shape, the arithmetic mean roughness Ra, the average length RSm of the roughness curve elements, the maximum cross-sectional height Rt of the roughness curve, and the skewness Rsk were obtained, respectively.

[Anti-glare]
A fluorescent lamp with no louver was projected on the laminated body, and the glare of the specularly reflected light was visually confirmed and evaluated according to the following criteria. ◎: No glare ○: Slight glare × : I feel glare.

[Steel wool (SW) resistance]
Using a steel wool durability tester equipped with a 1 cm diameter stick covered with steel wool # 0000, the load was changed at room temperature (20 to 25 ° C) at a speed of 50 mm / sec and a distance of 5 cm. After rubbing the surface of the dazzling layer 100 times, it was visually confirmed to determine the maximum load that was not scratched.

Example 1 (Preparation of antiglare film)
An organic-inorganic hybrid coating liquid is coated on the PET film using a wire bar as a coating liquid for forming an antiglare layer, dried in an oven at 80 ° C. for 1 minute, and the coating layer has a drying thickness of 6 μm. (Transfer layer) was formed. Subsequently, the transfer film A was used, arranged so that the coated surface and the transfer surface of the transfer film A were in contact with each other, and passed through a roll laminator (manufactured by Toshiba Machine Co., Ltd.) to prepare a laminated body. Further, the uncured coat layer side is irradiated with ultraviolet rays having an integrated light intensity of 400 mJ / cm ^{2 using} a high-pressure mercury lamp (manufactured by Eye Graphics Co., Ltd.) in a nitrogen atmosphere, and then the transfer film A is peeled off from the laminate. An anti-glare film was obtained.

Comparative Example 1
The transfer film A was used as an antiglare film.

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

(Making anti-glare film)
The coating liquid 3 was coated on the PET film using a wire bar and dried in an oven at 80 ° C. for 1 minute to form a coating layer (transfer layer) so that the drying thickness was 6 μm. Subsequently, an antiglare film was obtained in the same manner as in Example 1 except that the transfer film B was used instead of the transfer film A.

Comparative Example 2
The transfer film B was used as an antiglare film.

Example 3
(Preparation of transfer film C)
The coating liquid 2 was coated on the PET film using a wire bar and dried in an oven at 80 ° C. for 1 minute to form a coating layer (transfer layer) so that the drying thickness was 10 μm. The Ra of the transfer surface was 0.33 μm, the RSm was 29 μm, the Rt was 1.8 μm, the Rsk was 0.3, and the water contact angle was 102 °.

(Making anti-glare film)
The coating liquid 3 was coated on the PET film using a wire bar and dried in an oven at 80 ° C. for 1 minute to form a coating layer (transfer layer) so that the drying thickness was 7 μm. Subsequently, an antiglare film was obtained in the same manner as in Example 1 except that the transfer film C was used instead of the transfer film A.

Comparative Example 3
The transfer film C was used as an antiglare film.

Table 1 shows the evaluation results of the antiglare films obtained in Examples and Comparative Examples.

As is clear from the results in Table 1, the antiglare film of the example can have both antiglare property and scratch resistance. On the other hand, the antiglare film of the comparative example cannot improve the scratch resistance.

The antiglare film of the present invention comprises various display devices such as a liquid crystal display device (LCD), a cathode tube display device, an organic or inorganic electroluminescence (EL) display, a field emission display (FED), and a surface electric field display (SED). It can be used as an anti-glare film used in display devices such as rear projection TV displays, and in particular, it has excellent scratch resistance, so it can be used for car navigation displays, game consoles, smartphones, personal computers (PCs) (tablet PCs, etc.). It is suitable for computer-pointing devices such as notebook-type or laptop-type PCs, desktop-type PCs, pen tablets, and display devices with touch panels such as televisions.

Claims (5)

A transfer film forming step of forming a transfer surface by phase separation by wet spinodal decomposition,
The transfer surface of the transfer film obtained in the transfer film forming step is used as a molding die, and a transfer step of forming a concavo-convex shape in which the transfer surface is inverted is formed on the transfer surface of the antiglare film precursor. It is a method of manufacturing an antiglare film including
The antiglare film has a surface shape in which the skewness Rsk is less than 0 and the average length RSm of the roughness curve element is 1 to 50 μm, and the surface 60 ° gloss is 1 to 30%. Manufacturing method , including layers. The production method according to claim 1, wherein the antiglare layer does not contain particles having a particle size of 3 μm or more. The production method according to claim 1 or 2, wherein the antiglare layer does not contain particles. The production method according to any one of claims 1 to 3, wherein the haze is 1 to 60%. The production method according to any one of claims 1 to 4, wherein the antiglare layer is a cured product of a curable composition containing a photocurable resin.