Antiglare film

Abstract

To enable providing an antiglare film having enough mechanical strength, and capable of suppressing rainbow unevenness at a low cost.SOLUTION: An antiglare film comprises: a base material film that satisfies a relationship indicated by an expression 1, and is a biaxially stretched film having an in-plane birefringence; and an antiglare layer that is arranged overlapping on the base material film. A surface on a side opposite a base material film side of the antiglare layer has a rugged shape in which a fractal parameter Safc is a value within a range more than 0.02 when a cut-off value λs of a short wavelength is set to 50 μm, and Smr1 is a value within a range more than 14% when a cut-off value λs of a long wavelength is set to 25 μm, and the cut-off value λs of the short wavelength is set to 2.6 μm. [Expression 1] A base material film thickness D (m)*retardation Re (m)≥1.0*10-10(m2).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an antiglare film to be attached to a display device, a polarizing plate, or the like.

Background Art

[0002] An antiglare film is attached to various display devices and polarizing plates. The antiglare film scatters incident light from the outside and protects the surface to which the antiglare film is attached from the outside. The antiglare film includes a base film and an antiglare layer disposed on top of the base film. The antiglare layer has a surface that is roughened by forming a fine uneven shape. Patent Document 1 describes an antiglare film using a biaxially stretched polyethylene terephthalate (hereinafter also referred to as PET) film as the base film.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Although an antiglare film using a biaxially stretched film, like the antiglare film of Patent Document 1, has sufficient mechanical strength, unwanted rainbow unevenness (also referred to as color unevenness or interference unevenness) may occur due to the influence of retardation. Patent Document 2 describes a method of preventing rainbow unevenness by using a polyester film with enhanced anisotropy by varying the degree of stretching in each stretching direction. However, in this case, the mechanical strength of the antiglare film decreases due to insufficient stretching compared to a normal biaxially stretched film. In addition, separate processes and equipment for adjusting the degree of stretching in each stretching direction are required, increasing production costs.

[0005] Therefore, an object of the present disclosure is to provide an antiglare film that has sufficient mechanical strength and can suppress rainbow unevenness at low cost.

Means for Solving the Problems

[0006] The antiglare film according to one aspect of the present disclosure includes a base film that is a biaxially stretched film satisfying the relationship shown in Formula 1 and having in-plane birefringence, and an antiglare layer disposed on the base film. The surface of the antiglare layer opposite to the base film side has an uneven shape in which the fractal parameter Safc, which is a fractal parameter when the short-wavelength cut-off value λs is set to 50 μm, is in the range of 0.02 or more, and Smr1, which is a value in the range of 14% or more when the long-wavelength cut-off value λc is set to 25 μm and the short-wavelength cut-off value λs is set to 2.6 μm. [Formula 1] Base film thickness D (m) × Retardation Re (m) ≥ 1.0 × 10 -10 (m 2 )

Advantages of the Invention

[0007] According to the above aspect of the present disclosure, an antiglare film having sufficient mechanical strength and capable of suppressing rainbow unevenness can be provided at low cost.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0009] As a result of investigations by the inventors of the present application, in an antiglare film, when the integrated value (D × Re) of the thickness D and retardation Re of the base film is set to a value in a range equal to or greater than a predetermined value, and the Safc value and Smr1 value of the concavo-convex shape of the surface on the side opposite to the base film side of the antiglare layer are each set to a value in a predetermined range, it has been confirmed that by using a biaxially stretched film as the base film, an excellent antiglare effect and an effect of preventing rainbow unevenness can be obtained while maintaining sufficient mechanical strength of the antiglare film. The antiglare film of the present disclosure has been made based on such findings.

[0010] Hereinafter, each embodiment of the present disclosure will be described with reference to the respective drawings. The cut-off value referred to in this document refers to a predetermined wavelength removed from a cross-sectional curve, defined in accordance with JIS B 0601:2001. Also, the term "glare" refers to a phenomenon defined in JIS C 1006:2019.

[0011] (First Embodiment) [Antiglare Film and Display Device] FIG. 1 is a cross-sectional view of a display device 1 according to the first embodiment. FIG. 2 is an enlarged cross-sectional view of the surface 4a of the antiglare layer 4 of the antiglare film 2 in FIG. 1. As shown in FIG. 1, the display device 1 includes a display element 16 and an antiglare film 2. As an example, the antiglare film 2 is attached to the display surface 16a of the display element 16. The antiglare film 2 has a plurality of functions. The antiglare film 2 scatters incident light incident on the display surface 16a to prevent glare. Also, the antiglare film 2 protects the display surface 16a from the outside.

[0012] The types of the display element 16 are not limited. For example, the display element 16 includes displays such as a liquid crystal display (LCD), an organic EL display (OLED), an inorganic EL display, and a plasma display panel (PDP). Examples of the display device 1 include a personal computer (PC), a monitor, a television, a smartphone, and the like.

[0013] The antiglare film 2 includes a base film 3, an antiglare layer 4, and an adhesive layer 5. The adhesive layer 5 includes a material that hardly affects the optical properties of the antiglare film 2, such as optical adhesive. Another layer may be disposed between the base film 3 and the antiglare layer 4. The base film 3 is disposed so as to cover the display surface 16a and supports the antiglare layer 4. The base film 3 of the present embodiment covers the entire surface of the display surface 16a. The base film 3 is a biaxially stretched film that satisfies the relationship shown in the following formula 1 and has an in-plane birefringence. [Formula 1] Base film thickness D (m) × Retardation Re (m) ≥ 1.0 × 10 -10 (m 2 )

[0014] The retardation Re refers to the birefringence phase difference. That is, the retardation Re is calculated by the following formula 2 based on the refractive index (nx) in the direction in which the refractive index is the largest in the plane of the base film 3 (slow axis direction), the refractive index (ny) in the direction orthogonal to the slow axis direction (fast axis direction), and the thickness D of the base film 3. [Formula 2] Retardation Re (m) = (nx - ny) × Base film thickness D (m)

[0015] As an example, the base film thickness D × retardation Re (hereinafter, also simply referred to as "integrated value (D × Re)") is preferably 1.5 × 10 -10 (m 2 ) or more, and 2.0 × 10 -10 (m 2)The above is more desirable. By setting the integrated value (D×Re) to a value equal to or greater than the lower limit value shown in Formula 1, for example, it is possible to prevent a problem in which the rainbow unevenness becomes too strong and the rainbow unevenness cannot be sufficiently suppressed only by the transmitted light scattering due to the uneven shape of the surface of the antiglare layer. The upper limit value of the integrated value (D×Re) is not particularly limited, but is 6.0×10 -10 (m 2 )、5.0×10 -10 (m 2 )、or 4.0×10 -10 (m 2 )Any of these values can be exemplified. In the antiglare film 2, the integrated value is set to a value in the range of 1.0×10 -10 (m 2 ) or more. As will be described later, the surface 4a on the side opposite to the base film 3 side of the antiglare layer 4 has a fractal parameter Safc of 0.02 or more when the short-wavelength cut-off value λs is set to 50 μm, and Smr1 when the long-wavelength cut-off value λc is set to 25 μm and the short-wavelength cut-off value λs is set to 2.6 μm. By having an uneven shape that is a value in the range of 14% or more, rainbow unevenness can be appropriately suppressed. As an example, the base film 3 has a retardation Re in the range of 1000 nm or more and 4000 nm or less. The value of the retardation Re of the base film 3 is not limited to this.

[0016] The base film 3, which is a biaxially stretched film, is sufficiently stretched in the slow axis direction and the fast axis direction during manufacturing, for example, unlike the film of Patent Document 2. Therefore, for example, when an external force is applied, damage such as cracks is less likely to occur in the base film 3 because the degree of stretching in one of the two directions is lower than that in the other direction. As a result, the base film 3 has good mechanical strength. Specifically, the base film 3 has, for example, a difference in breaking strength (MPa) between the slow axis direction and the fast axis direction suppressed to a value in the range of less than 30%. Further, the base film 3 has, for example, a difference in elongation at break (%) between the slow axis direction and the fast axis direction suppressed to a value in the range of less than 60%. The breaking strength and elongation at break referred to here refer to values measured by a method conforming to JIS-C-2151:2019 and ASTM-D-882.

[0017] The antiglare layer 4 is disposed on top of the base film 3. As shown in FIG. 2, the surface 4a of the antiglare layer 4 on the side opposite to the base film 3 side has a predetermined uneven shape. As an example, the surface 4a of the antiglare layer 4 is exposed to the outside. The antiglare layer 4 imparts antiglare properties to the antiglare film 2, and scatters and reflects incident light from the outside to prevent unnecessary reflection on the display surface 16a. The antiglare layer 4 also functions as a hard coat (HC) layer that protects the display surface 16a. The surface 4a of the antiglare layer 4 has an uneven shape in which the fractal parameter Safc is in the range of 0.02 or more when the short-wavelength cut-off value λs is set to 50 μm, and Smr1 is in the range of 14% or more when the long-wavelength cut-off value λc is set to 25 μm and the short-wavelength cut-off value λs is set to 2.6 μm.

[0018] Here, Safc (Areal fractal complexity) is a parameter described in item 4.4.9.5 of ISO25178-2:2012, which is an international standard for surface roughness. Safc is equal to -1000 times the slope of the approximate straight line when the relationship between the specific surface area and the scale is plotted on a double logarithmic graph, and is related to the fractal dimension. The larger the Safc (in other words, the steeper the slope of the approximate straight line), the larger the fractal dimension, and the more complex the surface shape is evaluated.

[0019] By setting the cut-off value λs of the short wavelength during the measurement of the Safc to 50 μm, for example, uneven shapes that have no influence on the rainbow unevenness of the surface 4a of the antiglare layer 4 can be removed. Also, for example, the higher the value of the Safc when the cut-off value λs of the short wavelength is set to 50 μm, the higher the self-similarity and the finer structure of the uneven shape of the surface 4a of the antiglare layer 4 become. Thereby, transmitted light can be scattered at the surface 4a of the antiglare layer 4, making it easier to suppress rainbow unevenness. The Safc preferably has a value in the range of, for example, 0.02 or more and 1.00 or less, and more preferably in the range of 0.03 or more and 0.50 or less. The upper limit value of the Safc can be set as appropriate. Also, for example, by setting the upper limit value of the Safc to 1.00, it is possible to easily visually recognize even small characters displayed on the display surface 16a on which the antiglare film 2 is mounted.

[0020] Smr1 is a functional parameter described in ISO25178-2:2012. In a graph showing a load curve, among the straight lines where the difference in the Smr values of the load area ratios at two points of a certain height is 40%, the straight line with the smallest slope is defined as the equivalent straight line. When the difference in height at 0% and 100% of the load area ratio of this equivalent straight line is defined as the core part Sk, the area load ratio (%) that separates the protruding peak part above the height of the core part from the core part is defined as Smr1.

[0021] By setting the cut-off value λc of the long wavelength during the measurement of the Smr1 to 25 μm, for example, large uneven shapes that have no influence on the rainbow unevenness of the surface 4a of the antiglare layer 4 can be removed. Also, for example, the higher the value of the Smr1 when the cut-off value λc of the long wavelength is set to 25 μm, the easier it is to scatter transmitted light at the surface 4a of the antiglare layer 4 and suppress rainbow unevenness. The Smr1 preferably has a value in the range of, for example, 14% or more and 50% or less, and more preferably in the range of 15% or more and 30% or less. The upper limit value of the Smr1 can be set as appropriate. For example, by setting the upper limit value of the Smr1 to 50%, for example, the ratio of the convex parts of the uneven shape of the surface 4a of the antiglare layer 4 can be suppressed, and it is easier to maintain the mechanical strength of the antiglare film 2.

[0022] According to the antiglare film 2 having the above configuration, by setting the concavo-convex shape of the surface 4a of the antiglare layer 4 to the above-mentioned respective values of Safc and Smr1, the concavo-convex shape is formed so as to have a steep and high number density concavo-convex distribution structure. Thereby, the incident light on the surface 4a of the antiglare layer 4 is scattered, and the reflection of external light on the surface 4a of the antiglare layer 4 is appropriately suppressed. Therefore, the deterioration of the image display performance of the display device 1 is suppressed.

[0023] Further, by configuring the antiglare film 2 to include the antiglare layer 4 having the surface 4a with the concavo-convex shape and the base film 3 satisfying Formula 1, the base film 3 is formed of a biaxially stretched film to maintain sufficient mechanical strength, and an antiglare film 2 having excellent antiglare effect and rainbow unevenness prevention effect can be realized at low cost.

[0024] [Configuration example of base film] The base film 3 contains a resin material. Examples of the resin material of the base film 3 include, for example, polymers having transparency. Specific resin materials of the base film 3 include cellulose derivatives (such as cellulose acetate such as cellulose triacetate (TAC) and cellulose diacetate), polyester resins (such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polyarylate resins), polysulfone resins (such as polysulfone and polyethersulfone (PES)), polyether ketone resins (such as polyether ketone (PEK) and polyether ether ketone (PEEK)), polycarbonate resins (PC), polyolefin resins (such as polyethylene and polypropylene), cyclic polyolefin resins (such as the film "ARTON" (registered trademark) manufactured by JSR Corporation and the film "ZEONEX" (registered trademark) manufactured by Nippon Zeon Co., Ltd.), halogen-containing resins (such as polyvinylidene chloride), (meth)acrylic resins, styrene resins (such as polystyrene), vinyl acetate or vinyl alcohol resins (such as polyvinyl alcohol (PVA)).

[0025] The thickness D of the base film 3 can be appropriately set within the range where Equation 1 holds. The thickness D of the base film 3 is preferably, for example, a value in the range of 20 μm or more and 500 μm or less, more preferably in the range of 50 μm or more and 200 μm or less, and even more preferably in the range of 75 μm or more and 150 μm or less.

[0026] [Configuration Example of Anti-Glare Layer] The anti-glare layer 4 of the first embodiment contains a plurality of resin components and has a phase separation structure of the plurality of resin components. The anti-glare layer 4 has, as an example, a surface 4a on which a plurality of convex portions are dispersedly arranged. Thereby, the surface 4a of the anti-glare layer 4 of the present embodiment has an island structure formed by the plurality of convex portions and the concave portions therebetween. The anti-glare layer 4 exhibits anti-glare properties due to the uneven shape formed by the plurality of convex portions and the concave portions therebetween. The anti-glare film 2 includes such an anti-glare layer 4, and thus is excellent in the balance between the haze value and the transmission image sharpness (imaging property). Note that the surface 4a of the anti-glare layer 4 may have a co-continuous phase structure in which a plurality of convex portions are arranged in a dense state.

[0027] Further, in the anti-glare film 2, light from the display surface 16a that passes through the anti-glare layer 4 is prevented from being refracted by the unevenness on the surface of the anti-glare layer 4 or from making the pixels of the display surface 16a appear enlarged due to the lens effect of the uneven shape of the surface 4a of the anti-glare layer 4, and the glare of the display surface 16a is suppressed. Thereby, even when the anti-glare film 2 is attached to the display surface 16a having high-definition pixels, it is possible to highly suppress the glare of the display surface 16a while ensuring anti-glare properties, and it is also possible to suppress the blurring of characters and images.

[0028] As will be described later, the phase separation structure of the anti-glare layer 4 is formed by spinodal decomposition (wet spinodal decomposition) from the liquid phase using a solution that becomes the material of the anti-glare layer 4. For details of the anti-glare layer 4, for example, reference can be made to the description in Japanese Patent Application No. 2012-231496.

[0029] Examples of the polymer included in the antiglare layer 4 include thermoplastic resins. Examples of the thermoplastic resins include styrene resins, (meth)acrylic resins, vinyl organic acid ester resins, vinyl ether resins, halogen-containing resins, olefin resins (including alicyclic olefin resins), polycarbonate resins, polyester resins, polyamide resins, thermoplastic polyurethane resins, polysulfone resins (such as polyethersulfone and polysulfone), polyphenylene ether resins (such as polymers of 2,6-xylenol), cellulose derivatives (such as cellulose esters, cellulose carbamates, and cellulose ethers), silicone resins (such as polydimethylsiloxane and polymethylphenylsiloxane), rubbers or elastomers (such as diene rubbers such as polybutadiene and polyisoprene, styrene-butadiene copolymers, acrylonitrile-butadiene copolymers, acrylic rubbers, urethane rubbers, and silicone rubbers). These thermoplastic resins can be used alone or in combinations of two or more.

[0030] Examples of the polymer also include those having a functional group involved in a curing reaction or a functional group that reacts with a curable compound. This polymer may have the functional group in the main chain or side chain.

[0031] Examples of the functional group include a condensable group or a reactive group (for example, a hydroxyl group, an acid anhydride group, a carboxyl group, an amino group or an imino group, an epoxy group, a glycidyl group, an isocyanate group), a polymerizable group (for example, a C 2-6 alkenyl group such as vinyl, propenyl, isopropenyl, butenyl, and allyl groups, a C 2-6 alkynyl group such as ethynyl, propynyl, and butynyl groups, a C 2-6 alkenylidene group such as vinylidene group, or a group having these polymerizable groups ((meth)acryloyl group, etc.). Among these functional groups, a polymerizable group is desirable.

[0032] Further, the antiglare layer 4 may contain a plurality of types of polymers. Each of these polymers may be phase-separable by spinodal decomposition from a liquid phase, or may be incompatible with each other. The combination of the first polymer and the second polymer contained in the plurality of types of polymers is not particularly limited, but those that are incompatible with each other near the processing temperature can be used.

[0033] For example, when the first polymer is a styrene-based resin (such as polystyrene, styrene-acrylonitrile copolymer, etc.), examples of the second polymer include cellulose derivatives (such as cellulose esters such as cellulose acetate propionate), (meth)acrylic resins (such as polymethyl methacrylate), alicyclic olefin-based resins (such as polymers having norbornene as a monomer), polycarbonate-based resins, polyester-based resins (such as poly C 2-4 alkylene arylate copolyesters, etc.).

[0034] Also, for example, when the first polymer is a cellulose derivative (such as cellulose esters such as cellulose acetate propionate), examples of the second polymer include styrene-based resins (such as polystyrene, styrene-acrylonitrile copolymer, etc.), (meth)acrylic resins, alicyclic olefin-based resins (such as polymers having norbornene as a monomer), polycarbonate-based resins, polyester-based resins (such as poly C 2-4 alkylene arylate copolyesters, etc.).

[0035] The plurality of types of polymers may contain at least cellulose esters (such as cellulose C 2-4 alkyl carboxylic acid esters such as cellulose diacetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, etc.).

[0036] Here, the phase separation structure of the antiglare layer 4 is fixed by curing the precursor of the curable resin contained in the plurality of resin components by active energy rays (such as ultraviolet rays or electron beams) or heat during the production of the antiglare layer 4. Further, such a curable resin imparts scratch resistance and durability to the antiglare layer 4.

[0037] From the viewpoint of obtaining the scratch resistance of the antiglare layer 4, it is desirable that at least one polymer contained in the plurality of types of polymers is a polymer having a functional group capable of reacting with the curable resin precursor in the side chain. As the polymers forming the phase separation structure, in addition to the two polymers incompatible with each other described above, thermoplastic resins and other polymers may be included. The weight ratio M1 / M2 of the weight M1 of the first polymer and the weight M2 of the second polymer, and the glass transition temperature of the polymer can be set as appropriate.

[0038] Examples of the curable resin precursor include curable compounds having functional groups that react with active energy rays (such as ultraviolet rays or electron beams) or heat, and forming a resin (particularly a cured resin or a crosslinked resin) by curing or crosslinking with these functional groups.

[0039] Examples of such compounds include thermosetting compounds or thermosetting resins (low molecular weight compounds having epoxy groups, polymerizable groups, isocyanate groups, alkoxysilyl groups, silanol groups, etc. (for example, epoxy resins, unsaturated polyester resins, urethane resins, silicone resins, etc.)), photocurable (ionizing radiation curable) compounds (such as ultraviolet curable compounds such as photocurable monomers and oligomers) that are cured by ultraviolet rays or electron beams, etc.

[0040] Desirable curable resin precursors include photocurable compounds that can be cured in a short time by ultraviolet rays, electron beams, etc. Among these, ultraviolet curable compounds are particularly practical. In order to improve resistance such as scratch resistance, it is desirable for the photocurable compound to have two or more (desirably 2 to 15, more desirably about 4 to 10) polymerizable unsaturated bonds in the molecule. Specifically, the photocurable compound is desirably an epoxy (meth)acrylate, urethane (meth)acrylate, polyester (meth)acrylate, silicone (meth)acrylate, or a polyfunctional monomer having at least two polymerizable unsaturated bonds.

[0041] The curable resin precursor may contain a curing agent according to its type. For example, the thermosetting resin precursor may contain curing agents such as amines and polyvalent carboxylic acids, and the photocurable resin precursor may contain a photoinitiator. Examples of the photoinitiator include conventional components such as acetophenones or propiophenones, benzyls, benzoins, benzophenones, thioxanthones, acylphosphine oxides, etc.

[0042] The curable resin precursor may also contain a curing accelerator. For example, the photocurable resin precursor may contain a photocuring accelerator such as tertiary amines (such as dialkylaminobenzoic acid esters), phosphine-based photopolymerization accelerators, etc.

[0043] In the manufacturing process of the antiglare layer 4, at least two components out of the polymer and the curable resin precursor contained in the solution that becomes the material of the antiglare layer 4 are used as a combination that phase-separates from each other near the processing temperature. Examples of the combination for phase separation include (a) a combination in which multiple types of polymers are incompatible with each other and phase-separate, (b) a combination in which a polymer and a curable resin precursor are incompatible and phase-separate, or (c) a combination in which multiple curable resin precursors are incompatible with each other and phase-separate, etc. Among these combinations, usually, (a) a combination of multiple types of polymers or (b) a combination of a polymer and a curable resin precursor are mentioned. In particular, (a) a combination of multiple types of polymers is desirable.

[0044] Here, usually, the refractive index of the polymer is different from that of the cured resin or crosslinked resin formed by curing the curable resin precursor. Also, usually, the refractive indices of multiple types of polymers (the first polymer and the second polymer) are different from each other. The refractive index difference between the polymer and the cured resin or crosslinked resin, and the refractive index difference between multiple types of polymers (the first polymer and the second polymer) are desirably values in the range of, for example, 0 or more and 0.04 or less, and more desirably values in the range of 0 or more and 0.02 or less.

[0045] The antiglare layer 4 may contain a matrix resin having a phase-separated structure and a plurality of fine particles (fillers) dispersed in the matrix resin. The fine particles may be either organic fine particles or inorganic fine particles. The antiglare layer 4 may contain multiple types of fine particles having different materials or average particle diameters.

[0046] Examples of the organic fine particles include crosslinked acrylic particles and crosslinked styrene particles. Examples of the inorganic fine particles include silica (SiO 2 ), zirconia (ZrO 2 ), titania (TiO 2) Examples of fine particles of other various metal oxides can be given. Examples of metal oxides include indium tin oxide, tin oxide, indium oxide, germanium oxide, zinc oxide, and aluminum oxide. Further, examples of inorganic fine particles include metal fluoride particles, metal sulfide particles, metal nitride particles, and metal particles. The fine particles contained in the antiglare layer 4 are preferably those having good transparency, for example. For example, when the fine particles contain silica, it is easier to improve the hardness of the antiglare film 2, for example. The refractive index difference between the fine particles contained in the antiglare layer 4 and the matrix resin can be set to a value in the range of 0 or more and 0.5 or less, for example. This refractive index difference is preferably a value in the range of 0 or more and 0.3 or less, and more preferably a value in the range of 0 or more and 0.2 or less, for example.

[0047] The average particle diameter of the fine particles is not particularly limited and can be set to a value in the range of, for example, 0.5 μm or more and 10 μm or less. This average particle diameter is preferably a value in the range of 0.5 μm or more and 8.0 μm or less, and more preferably a value in the range of 1.0 μm or more and 6.0 μm or less, for example.

[0048] The average particle diameter referred to in this document is, for example, the volume average particle diameter (MV value) measured by the laser diffraction scattering method (the same applies to the average particle diameter mentioned below). The fine particles may be solid or hollow. For example, by setting the average particle diameter of the fine particles to a value that is not too small, antiglare properties can be easily obtained. Also, for example, by setting the average particle diameter of the fine particles to a value that is not too large, it is easy to suppress glare.

[0049] The thickness dimension of the antiglare layer 4 can be set as appropriate, but is, for example, a value in the range of 0.3 μm or more and 20 μm or less. This thickness dimension is preferably a value in the range of 1 μm or more and 15 μm or less, and more preferably a value in the range of 1 μm or more and 10 μm or less, for example. This thickness dimension can usually be set to a value in the range of 2 μm or more and 10 μm or less (particularly a value in the range of 3 μm or more and 7 μm or less), for example.

[0050] In the antiglare layer 4, conventional additives may be included within a range that does not impair the optical properties, such as organic or inorganic particles, stabilizers (antioxidants, ultraviolet absorbers, etc.), surfactants, water-soluble polymers, fillers, crosslinking agents, coupling agents, colorants, flame retardants, lubricants, waxes, preservatives, viscosity modifiers, thickeners, leveling agents, defoaming agents, and the like.

[0051] [Example of manufacturing method of antiglare film] As an example, the manufacturing method of the antiglare film 2 includes a preparation step of preparing a solution (hereinafter also simply referred to as a solution) that serves as a material for the antiglare layer 4, a forming step of applying the solution prepared in the preparation step to the surface of a predetermined support (the base film 3 in this embodiment) and evaporating the solvent in the solution to form a phase separation structure by spinodal decomposition from the liquid phase, and a curing step of curing the curable resin precursor after the forming step.

[0052] In the preparation step, a solution containing a solvent and a resin composition for forming the antiglare layer 4 is prepared. The solvent can be selected according to the types and solubility of the polymers and curable resin precursors contained in the aforementioned antiglare layer 4. The solvent may be any one that can uniformly dissolve at least the solid components (multiple types of polymers, curable resin precursors, reaction initiators, and other additives).

[0053] Examples of the solvent include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (ethanol, isopropanol, butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides (dimethyl sulfoxide, etc.), amides (dimethylformamide, dimethylacetamide, etc.), and the like. Also, the solvent may be a mixed solvent.

[0054] As the resin composition, a composition containing the thermoplastic resin, the photocurable compound, the photopolymerization initiator, the thermoplastic resin, and the photocurable compound is desirable. Alternatively, as the resin composition, a composition containing the plurality of types of polymers that are incompatible with each other, the photocurable compound, and the photopolymerization initiator is desirable.

[0055] The concentration of the solutes (polymers, curable resin precursors, reaction initiators, and other additives) in the solution can be adjusted within a range in which phase separation of the plurality of resin components occurs and a range in which the casting property and coating property of the solution are not impaired.

[0056] Here, the external haze value, internal haze value, antiglare property, etc. of the antiglare layer 4 can vary depending on the combination and weight ratio of the resin composition in the solution, or the construction conditions of the preparation process, formation process, and curing process. Therefore, by forming the antiglare layer while changing each condition and measuring and grasping in advance the physical properties of the obtained antiglare layer, the antiglare film 2 having the target physical properties can be manufactured.

[0057] In the formation process, the solution prepared in the preparation process is cast or coated on the surface of a support (here, the base film 3 as an example). Examples of the casting method or coating method of the solution include conventional methods such as spraying, spinner, roll coater, air knife coater, blade coater, rod coater, reverse coater, bar coater, comma coater, dip, dip-squeeze coater, die coater, gravure coater, microgravure coater, silk screen coater, etc.

[0058] The solvent is removed by evaporation by drying from the solution cast or coated on the surface of the support. Along with the concentration of the solution in this evaporation process, phase separation due to spinodal decomposition from the liquid phase of the plurality of resin components occurs to form a phase separation structure. The uneven shape of the surface 4a due to the phase separation structure can be formed by setting drying conditions and formulations such that the melt fluidity of the resin components after solvent evaporation is somewhat high.

[0059] For example, evaporation of the solvent is preferably carried out by heat drying because it is easy to form convex portions on the surface 4a of the antiglare layer 4. By adjusting so that the drying temperature is not too low and the drying time does not become too short, sufficient heat quantity can be imparted to the resin component, preventing a decrease in the melt fluidity of the resin component and making it easy to form convex portions.

[0060] On the other hand, if the drying temperature is too high or the drying time is too long, although the convex portions once formed may flow and the height may decrease, the structure of the convex portions is maintained. Therefore, the drying temperature and the drying time can be used as means to adjust the antiglare property and the slipperiness of the antiglare layer 4 by changing the height of the convex portions.

[0061] As the co-continuous phase structure is formed and coarsens with the progress of spinodal decomposition from the liquid phase of a plurality of resin components, the continuous phase becomes discontinuous and a droplet phase structure (an island structure of independent phases such as spherical, true spherical, disk-shaped, or ellipsoidal) is formed. Here, depending on the degree of phase separation, an intermediate structure between the co-continuous phase structure and the droplet phase structure (a phase structure in the process of transitioning from the co-continuous phase to the droplet phase) can also be formed. After solvent removal, a layer having fine irregularities on the surface is formed.

[0062] In this way, by forming fine irregularities on the surface of the layer by phase separation, for example, the external haze value of the antiglare layer 4 can be adjusted without dispersing fine particles in the antiglare layer 4. Also, by omitting the fine particles, it becomes easier to adjust the haze value of the antiglare layer 4 while suppressing the internal haze value compared to the external haze value. Note that an antiglare layer 4 containing fine particles can also be formed by adding fine particles to the solution in the preparation process.

[0063] In the curing step, the curable resin precursor in the solution is cured to fix the phase separation structure formed in the forming step and form the antiglare layer 4. Curing of the curable resin precursor is carried out by heating, irradiation with active energy rays, or a combination of these methods according to the type of the curable resin precursor. The active energy rays to be irradiated are selected according to the type of photocurable components and the like.

[0064] Irradiation with active energy rays may be performed in an inert gas atmosphere. When the active energy rays are ultraviolet rays, as the light source, a far ultraviolet lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a halogen lamp, a laser light source (light sources such as a helium-cadmium laser, an excimer laser, etc.) can be used.

[0065] When forming the adhesive layer 5, after preparing a solution containing an adhesive component, the adhesive layer 5 can be formed by applying and drying the solution on the other surface of the base film 3 by a conventional method, for example, the casting method or the coating method described above in the forming step. By going through each of the above steps, the antiglare film 2 is manufactured.

[0066] Here, for example, not only can the unevenness on the surface 4a of the antiglare layer 4 be reduced, but also the inclination of the unevenness can be increased to steepen the unevenness and the number of unevenness can be increased, thereby improving the antiglare property of the antiglare film 2 together with the glare suppression effect.

[0067] Note that the basic method for forming the antiglare layer of the present disclosure is not particularly limited to the method described above, and known methods can be used. As the known method, in addition to the forming method based on the phase separation structure of the plurality of resin components described above, as described in the second embodiment, a forming method based on a fine particle dispersion method for forming the antiglare layer 104 using the matrix resin 40 and the plurality of fine particles 41 can be exemplified. Further, a transfer forming method for forming the antiglare layer by transferring the uneven shape on the surface using a previously prepared mold (master mold) can be exemplified. In this case, as the mold, for example, a mold in which a metal film is formed on a previously manufactured antiglare film or the like by electrodeposition coating or the like can be used.

[0068] As a basic method for forming the antiglare layer, a method of forming an uneven shape on the surface of the antiglare layer material by cutting the surface of the antiglare layer material using a laser or the like can also be exemplified. Further, a method of polishing the antiglare layer material by a shot blasting method or the like using a projection material such as sand or beads to form an uneven shape on the surface of the antiglare layer can also be exemplified. Further, a method of forming an uneven shape on the surface of the antiglare layer by etching the antiglare layer material can also be exemplified. Hereinafter, other embodiments will be described centering on the differences from the first embodiment.

[0069] (Second Embodiment) [Antiglare Film] FIG. 3 is an enlarged cross-sectional view of the surface 104a of the antiglare layer 104 of the antiglare film 102 according to the second embodiment. As shown in FIG. 3, the antiglare film 102 according to the second embodiment includes an antiglare layer 104. The antiglare film 102 includes a base film 3 in the same manner as the antiglare film 2. The surface 104a on the side opposite to the base film 3 side of the antiglare layer 104 has the same uneven shape as the surface 4a of the antiglare layer 4.

[0070] The antiglare layer 104 includes a matrix resin 40 and a plurality of fine particles 41 dispersed in the matrix resin 40. Thereby, the antiglare layer 104 has a fine particle dispersion structure. Among the plurality of fine particles 41 dispersed in the matrix resin 40 in the antiglare layer 104, a part of the fine particles 41 are arranged so as to protrude from the surface of the matrix resin 40 to the outside, whereby an uneven shape is formed on the surface 104a of the antiglare layer 104.

[0071] Even when a plurality of fine particles 41 are used to form the uneven shape of the surface 104a of the antiglare layer 104 as in the present embodiment, by selecting a material such that the repulsive interaction between the fine particles 41 and other resins and solvents becomes strong during the formation of the antiglare layer 104, appropriate aggregation of the fine particles 41 is caused, and a steep and high number density uneven distribution structure can be formed on the surface 104a of the antiglare layer 104.

[0072] The shape of the fine particles 41 is not limited and may be spherical or may be formed in an ellipsoidal shape. Also, the fine particles 41 are formed solid, but may be formed hollow. When the fine particles 41 are formed hollow, the hollow portion of the fine particles 41 may be filled with air or other gas. In the antiglare layer 104, each fine particle 41 may be dispersed as a primary particle, or a plurality of secondary particles formed by aggregation of a plurality of fine particles 41 may be dispersed.

[0073] The refractive index difference between the matrix resin 40 and the fine particles 41 is set to a value in the range of, for example, 0 or more and 0.5 or less. This refractive index difference is desirably a value in the range of, for example, 0 or more and 0.3 or less, and more desirably a value in the range of 0 or more and 0.2 or less.

[0074] The fine particles 41 are set to have an average particle size in the range of, for example, 0.5 μm or more and 10 μm or less. The average particle size of the fine particles 41 is desirably a value in the range of, for example, 0.5 μm or more and 8.0 μm or less, and more desirably a value in the range of 1.0 μm or more and 6.0 μm or less.

[0075] Also, for example, it is desirable that the variation in the particle size of the fine particles 41 is small. In this case, for example, in the particle size distribution of the fine particles 41 included in the antiglare layer 104, it is desirable that the average particle size of 50% by weight or more of the fine particles 41 included in the antiglare layer 104 is within a variation of 1.0 μm.

[0076] In this way, the fine particles 41 having a relatively uniform particle size and an average particle size set in the above range form uniform and appropriate irregularities on the surface of the antiglare layer 104. The ratio of the weight of the matrix resin 40 in the antiglare layer 104 to the total weight of the plurality of fine particles 41 can be set as appropriate. In the present embodiment, the ratio G2 / G1 of the weight G1 of the matrix resin 40 in the antiglare layer 104 to the total weight G2 of the plurality of fine particles 41 is set to a value in the range of, for example, 0.01 or more and 2.0 or less. The ratio G2 / G1 is desirably a value in the range of, for example, 0.02 or more and 1.5 or less, and more desirably a value in the range of 0.03 or more and 1.0 or less.

[0077] The fine particles 41 dispersed in the matrix resin 40 may be either inorganic or organic. As the fine particles 41, those having good transparency are desirable, for example. Examples of the organic fine particles include plastic beads. Examples of the plastic beads include styrene beads (refractive index 1.59), melamine beads (refractive index 1.57), acrylic beads (refractive index 1.49), acrylic-styrene beads (refractive index 1.54), polycarbonate beads, polyethylene beads, etc. The styrene beads may be crosslinked styrene beads, and the acrylic beads may be crosslinked acrylic beads. The plastic beads desirably have a hydrophobic group on the surface. Examples of such plastic beads include styrene beads.

[0078] Examples of the matrix resin 40 can include at least any one of a photocurable resin cured by active energy rays, a solvent-drying type resin cured by drying a solvent added during coating, and a thermosetting resin.

[0079] Examples of the photocurable resin include those having acrylate-based functional groups, such as oligomers, prepolymers, and reactive diluents of (meth)acrylates of polyfunctional compounds such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and polyhydric alcohols.

[0080] Examples of these specific examples include monofunctional monomers such as ethyl (meth)acrylate, ethylhexyl (meth)acrylate, styrene, methylstyrene, N-vinylpyrrolidone, etc., and polyfunctional monomers, for example, polymethylolpropane tri(meth)acrylate, hexanediol (meth)acrylate, tripropylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, etc.

[0081] When the photocurable resin is an ultraviolet curable resin, it is desirable to use a photoinitiator. Examples of the photoinitiator include acetophenones, benzophenones, Michler's benzoyl benzoate, α-amyloxime ester, tetramethylthiuram monosulfide, thioxanthones. It is also desirable to mix and use a photosensitizer in the photocurable resin. Examples of the photosensitizer include n-butylamine, triethylamine, poly-n-butylphosphine, etc.

[0082] Examples of the solvent-drying type resin can include known thermoplastic resins. Examples of this thermoplastic resin include styrene resins such as polystyrene resin, acrylic resins, (meth)acrylic resins, vinyl resins such as vinyl acetate resin, vinyl ether resins, acetal resins, halogen-containing resins, alicyclic olefin resins, polycarbonate resins, polyester resins, polyamide resins, cellulose resins, cellulose derivatives, silicone resins, and rubber or elastomers, etc. As the solvent-drying type resin, a resin that is soluble in an organic solvent and is particularly excellent in moldability, film-forming property, transparency, and weather resistance is desirable. Examples of such solvent-drying type resins can include styrene resins, (meth)acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (such as cellulose esters).

[0083] Examples of the thermosetting resin include phenolic resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea co-condensation resin, silicone resin, polysiloxane resin, and the like. When a thermosetting resin is used as the matrix resin 40, at least one of a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, a solvent, and a viscosity modifier may be used in combination.

[0084] [Example of manufacturing method of anti-glare film] As an example, the manufacturing method of the anti-glare film 102 includes a preparation step of preparing a solution that becomes the material of the anti-glare layer 104, a coating step of coating the solution prepared in the preparation step on the surface of a predetermined support (substrate film 3 in this embodiment), and a curing step of curing the resin in the coated solution.

[0085] In the preparation step, a solution containing a solvent, a resin composition for forming the anti-glare layer 104, and the fine particles 41 is prepared. Examples of the solvent include at least one of alcohols (such as isopropyl alcohol, methanol, and ethanol), ketones (such as methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and cyclohexanone), esters (such as methyl acetate, ethyl acetate, and butyl acetate), halogenated hydrocarbons, and aromatic hydrocarbons (such as toluene and xylene). A known leveling agent may be further added to the solution. For example, by using a fluorine-based or silicone-based leveling agent, good scratch resistance can be imparted to the anti-glare layer 104.

[0086] In the coating step, the solution prepared in the preparation step is cast or coated on the surface of the support (here, the substrate film 3 as an example) by the same method as in the first embodiment. The solvent is evaporated and removed from the solution cast or coated on the surface of the support by drying.

[0087] When the matrix resin 40 is a photocurable resin, after the coating step, as an example, a curing step using ultraviolet rays or electron beams is performed. Examples of the ultraviolet light source include light sources of various mercury lamps, ultraviolet carbon arc lamps, black lights, and metal halide lamps. Further, as the wavelength range of the ultraviolet rays, for example, a wavelength range of 190 nm or more and 380 nm or less can be exemplified.

[0088] Examples of the electron beam source include known electron beam accelerators. Specifically, various electron beam accelerators such as Van de Graaff type, Cockcroft-Walton type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high-frequency type can be exemplified.

[0089] When the matrix resin 40 contained in the solution cures, the positions of the fine particles 41 in the matrix resin 40 are fixed. Thereby, a plurality of fine particles 41 are dispersed in the matrix resin 40, and an antiglare layer 104 having a concavo-convex shape formed by the fine particles 41 is formed on the surface 104a.

[0090] (Third Embodiment) FIG. 4 is a partial cross-sectional view of an antiglare film 202 including an antireflection layer 9 having a first structure according to the third embodiment. FIG. 5 is a partial cross-sectional view of an antiglare film 302 including an antireflection layer 9 having a second structure according to the third embodiment. FIG. 6 is a partial cross-sectional view of an antiglare film 402 including an antireflection layer 9 having a third structure according to the third embodiment. In FIG. 6, an antireflection layer 9 having a four-layer structure is shown as an example.

[0091] As shown in FIGS. 4 to 6, the antiglare films 202, 302, and 402 of the present embodiment have an antireflection layer 9 disposed on the surface 4a of the antiglare layer 4 opposite to the base film 3 side. The antireflection layer 9 prevents reflection of external light. As shown in FIG. 4, the antireflection layer 9 has, for example, a first structure including only a single-layer low refractive index layer 90. Alternatively, as shown in FIG. 5, the antireflection layer 9 has a second structure including a laminated structure of a single-layer low refractive index layer 90 and a single-layer high refractive index layer 91 having a higher refractive index than the low refractive index layer 90. Or, as shown in FIG. 6, the antireflection layer 9 has a third structure which is a laminated structure of three or more layers including a low refractive index layer 90 and a high refractive index layer 91 arranged alternately. The low refractive index layer 90 has, for example, a lower refractive index than the antiglare layer 4. The low refractive index layer 90 may have antifouling properties. In this case, the low refractive index layer 90 may contain an antifouling agent such as a silicone-based compound or a fluorine-based compound.

[0092] The method for forming the low refractive index layer 90 and the high refractive index layer 91 is not particularly limited, and for example, a known wet method or dry method can be exemplified. When the antireflection layer 9 has the first structure or the second structure, for example, the wet method is desirable. When the antireflection layer 9 has the third structure, for example, the dry method is desirable.

[0093] The refractive index of the antireflection layer 9 is not particularly limited. Also, the thickness of the antireflection layer 9 can be set within a range where the antiglare property of the antiglare film 202 is ensured. For example, the thickness of the antireflection layer 9 can be set so that the spectral reflectance near 550 nm becomes the lowest when the spectral reflectance spectrum of the antiglare film 202 is measured.

[0094] When the antireflection layer 9 has the first structure or the second structure, as an example, the refractive index of the low refractive index layer 90 is a value in the range of 1.34 or more. In this case, the refractive index of the low refractive index layer 90 is desirably a value in the range of, for example, 1.34 or more and 1.45 or less, more desirably a value in the range of 1.34 or more and 1.4 or less, still more desirably a value in the range of 1.34 or more and 1.39 or less, and even more desirably a value in the range of 1.34 or more and 1.38 or less. For example, by setting the refractive index of the low refractive index layer 90 not to be too high, a decrease in the antireflection property of the antireflection layer 9 can be suppressed.

[0095] When the antireflection layer 9 has the first structure or the second structure, the thickness of the low refractive index layer 90 is desirably a value in the range of, for example, 50 nm or more and 300 nm or less, more desirably a value in the range of 60 nm or more and 150 nm or less, still more desirably a value in the range of 80 nm or more and 120 nm or less, and even more desirably a value in the range of 90 nm or more and 110 nm or less.

[0096] Regarding the configuration of the low refractive index layer 90, for example, the configurations of the low refractive index layers described in JP-A-2001-100006, JP-A-2008-58723, and WO2016 / 039125 can be referred to. The low refractive index layer 90 is, for example, composed of a composition containing a low refractive index resin. Further, the low refractive index layer 90 may be, for example, composed of a cured product of a composition containing a curable resin and a fluorine-containing compound or a low refractive index inorganic filler.

[0097] Examples of the low refractive index resin include fluorine resins such as methylpentene resin, diethylene glycol bis(allyl carbonate) resin, polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF). Examples of the curable resin include fluorine-free photocurable resins used as the material of the antiglare layer 4. Examples of the fluorine-containing compound include fluorine-containing photocurable resins used as the material of the antiglare layer 4.

[0098] The proportion of the fluorine-containing compound in the composition constituting the low refractive index layer 90 is, for example, a value in the range of 1% by mass or more with respect to the entire composition. The proportion may be, for example, a value in the range of 5% by mass or more and 90% by mass or less. Examples of the low refractive index inorganic filler include the fillers described in JP-A-2001-100006. As the inorganic filler, low refractive index fillers such as silica and magnesium fluoride are desirable, and silica is particularly desirable. Examples of silica include hollow silica described in JP-A-2001-233611 or JP-A-2003-192994. Among these, hollow silica is desirable, for example, from the viewpoint of being able to suppress an increase in haze and improve transparency.

[0099] Further, the number average particle diameter (number average primary particle diameter) measured by an electron microscope method of the inorganic filler (particularly, hollow silica) is, for example, a value in the range of 100 nm or less. As an example, this number average particle diameter is desirably a value in the range of 80 nm or less. As another example, this number average particle diameter is desirably a value in the range of 10 nm or more and 80 nm or less, and more desirably a value in the range of 20 nm or more and 70 nm or less.

[0100] The proportion of the low refractive index inorganic filler (particularly, hollow silica) in the composition constituting the low refractive index layer 90 is, for example, a value in the range of 1% by mass or more with respect to the entire composition. The proportion may be, for example, a value in the range of 5% by mass or more and 90% by mass or less. Further, the low refractive index inorganic filler may be surface-modified with a coupling agent (titanium coupling agent, silane coupling agent). Furthermore, the composition containing the low refractive index inorganic filler may contain other inorganic fillers in order to improve the coating film strength.

[0101] Further, the composition of the low refractive index layer 90 may contain a curing agent or a known additive used as a material for the antiglare layer 4. Further, the antiglare layer of the present embodiment may be formed by any of the forming methods described in the first and second embodiments.

[0102] As shown in Fig. 5, when the antireflection layer 9 has the second structure, it is desirable that the high refractive index layer 91 be disposed, for example, at a position closer to the antiglare layer 4 than the low refractive index layer 90. The refractive index of the high refractive index layer 91 can be appropriately set within a range higher than that of the low refractive index layer 90. Also in this case, the refractive index of the high refractive index layer 91 is, for example, a value in the range of 1.53 or more. Also in this case, the refractive index of the high refractive index layer 91 is desirably, for example, a value in the range of 1.54 or more, more desirably a value in the range of 1.55 or more, and even more desirably a value in the range of 1.56 or more. Also in this case, the refractive index of the high refractive index layer 91 is desirably, for example, a value in the range of 1.85 or less, more desirably a value in the range of 1.80 or less, and even more desirably a value in the range of 1.75 or less.

[0103] When the antireflection layer 9 has the second structure, the thickness of the high refractive index layer 91 is, for example, a value in the range of 200 nm or less. In this case, the thickness of the high refractive index layer 91 is desirably, for example, a value in the range of 180 nm or less, and more desirably a value in the range of 150 nm or less. Also in this case, the thickness of the high refractive index layer 91 is desirably, for example, a value in the range of 50 nm or more, and more desirably a value in the range of 70 nm or more.

[0104] Regarding the configuration of the high refractive index layer 91, for example, the configuration of the high refractive index layer described in JP-A-2016-097529 can be referred to. The high refractive index layer 91 is, for example, composed of a composition containing a high refractive index resin. Also, the high refractive index layer 91 may be, for example, composed of a cured product of a composition containing inorganic fine particles. As the particle size of the inorganic fine particles, a nanometer size can be exemplified. The number average particle size (number average primary particle size) of the inorganic fine particles is, for example, a value in the range of 1 nm or more and 100 nm or less. The number average particle size of the inorganic fine particles is desirably, for example, a value in the range of 2 nm or more and 50 nm or less, more desirably a value in the range of 3 nm or more and 40 nm or less, and even more desirably a value in the range of 5 nm or more and 30 nm or less. The number average particle size of the inorganic fine particles can be measured by a conventional method using a particle size distribution meter. The number average particle size of the inorganic fine particles can be measured, for example, based on the dynamic light scattering method using a particle size measuring device (laser particle size analyzer "PAR-III" manufactured by Otsuka Electronics Co., Ltd.).

[0105] The shape of the inorganic fine particles is not particularly limited. Examples of the shape of the inorganic fine particles include spherical, ellipsoidal, polyhedral (such as polyhedral pyramidal, cubic, rectangular parallelepiped, etc.), plate-like, rod-like, or amorphous, etc. As the shape of the inorganic fine particles, for example, an isotropic shape such as a substantially spherical shape is desirable from the viewpoint of being able to scatter light isotropically and improve visibility.

[0106] Examples of the inorganic compound constituting the inorganic fine particles include simple metals and metal oxides, etc. For example, from the viewpoint of being able to increase the refractive index of the high refractive index layer 91, metal oxides are desirable. Examples of the metal oxides include Group 4A metal oxides in the periodic table (such as titanium oxide, zirconium oxide, etc.), Group 5A metal oxides (such as vanadium oxide, etc.), Group 6A metal oxides (such as molybdenum oxide, tungsten oxide, etc.), Group 7A metal oxides (such as manganese oxide, etc.), Group 8 metal oxides (such as nickel oxide, iron oxide, etc.), Group 1B metal oxides (such as copper oxide, etc.), Group 2B metal oxides (such as zinc oxide, etc.), Group 3B metal oxides (such as aluminum oxide, indium oxide, etc.), Group 4B metal oxides (such as silicon oxide, tin oxide, etc.), Group 5B metal oxides (such as antimony oxide, etc.), etc. These metal oxides can be used alone or in combination of two or more. Among these metal oxides, for example, Group 4A metal oxides in the periodic table such as titanium oxide and zirconium oxide are desirable, and zirconium oxide is particularly desirable, from the viewpoint of being able to increase the refractive index of the high refractive index layer 91 at a low ratio and being able to suppress the increase in haze even when the addition amount increases.

[0107] The high refractive index resin contains, for example, a curable resin. Examples of the curable resin include ultraviolet curable resins. As the ultraviolet curable resin, for example, polyfunctional (meth)acrylates such as pentaerythritol tri(meth)acrylate and dipentaerythritol hexa(meth)acrylate are desirable.

[0108] As shown in FIG. 6, when the antireflection layer 9 has the third structure, for example, it is desirable that the third structure includes a low refractive index layer 90 disposed on the outermost surface of the antiglare film 202. When the antireflection layer 9 has the third structure, the thickness of each high refractive index layer 91 is, for example, desirably a value in the range of 10 nm or more and 200 nm or less, and more desirably a value in the range of 20 nm or more and 70 nm or less. Also in this case, the refractive index of each high refractive index layer 91 is, for example, desirably a value in the range of 2.00 or more and 2.60 or less.

[0109] Also when the antireflection layer 9 has the third structure, the thickness of each low refractive index layer 90 is, for example, desirably a value in the range of 5 nm or more and 200 nm or less, and more desirably a value in the range of 20 nm or more and 120 nm or less. Also in this case, the refractive index of each low refractive index layer 90 is, for example, desirably a value in the range of 1.20 or more and 1.60 or less.

[0110] Note that the antireflection layer 9 is not limited to having any of the first to third structures. The antireflection layer 9 may have a structure including another layer, for example, at least one intermediate refractive index layer having a refractive index higher than that of the low refractive index layer 90 and lower than that of the high refractive index layer 91. In this case, the intermediate refractive index layer may be combined with, for example, at least one of the low refractive index layer 90 or the high refractive index layer 91.

[0111] (Fourth Embodiment) FIG. 7 is a schematic cross-sectional view of the optical member 10 according to the fourth embodiment. As shown in FIG. 7, the optical member 10 is an application example of the antiglare film 2. The optical member 10 includes an antiglare film 2 and a polarizing plate 6 disposed on top of the antiglare film 2. The polarizing plate 6 polarizes incident light from the outside. The polarizing plate 6 of the present embodiment has a retardation film 8 and a plate-shaped polarizing element 7 disposed on top of the retardation film 8. Examples of the material of the polarizing element 7 include polyvinyl alcohol (PVA) dyed and stretched with iodine or the like, polyvinyl formal, polyvinyl acetal, and saponified ethylene-vinyl acetate copolymer. Examples of the material of the retardation film 8 include triacetyl cellulose and cycloolefin polymer. According to the present embodiment, the incident light on the retardation film 8 passes through the antiglare film 2 in the direction from the base film 3 to the antiglare layer 4 after entering and being polarized by the polarizing element 7.

[0112] Note that the optical member 10 may include any one of the antiglare films 102, 202, 302, and 402 of other embodiments instead of the antiglare film 2 of the first embodiment, for example. Also, the configuration of the polarizing plate 6 is not limited, and a known configuration can be adopted. For example, the polarizing plate 6 may include a protective film containing polyethylene terephthalate (PET) or the like.

[0113] (Fifth Embodiment) FIG. 8 is a schematic cross-sectional view of the display device 20 according to the fifth embodiment. As shown in FIG. 8, the display device 20 is an application example of the optical member 10. The display device 20 includes a light source 17, a polarizing plate 18 disposed on the optical path of the light source 17, a panel-shaped display element 15 disposed on top of the polarizing plate 18 with the surface opposite to the image display side facing the polarizing plate 18, and an optical member 10 disposed on the image display side of the display element 15. As an example, the display element 15 includes an LCD. The light source 17 is a backlight. The surface 4a of the antiglare layer 4 in the optical member 10 is located at the top in the thickness direction of the display device 20. The polarizing plate 18 is a polarizing plate different from the polarizing plate 6 included in the optical member 10.

[0114] When the display device 20 is driven, the light emitted from the light source 17 is polarized by the polarizing plate 18 and then sequentially enters each of the display element 15 and the optical member 10. Along with this, the image of the display element 16 is visually recognized by the light emitted from the surface 4a of the antiglare layer 4 of the optical member 10 to the outside.

[0115] (Confirmation test) Next, the performance confirmation test of the present disclosure will be described, but the present disclosure is not limited to the following examples. Based on the procedures shown below, antiglare films of Examples 1 to 13 and Comparative Examples 1 to 7 were manufactured. Examples 1, 3, 5, 7 to 13 include an antiglare layer 4 having a phase separation structure and correspond to the antiglare film 2. Examples 2 and 4 include an antiglare layer 104 having a fine particle dispersion structure and correspond to the antiglare film 102. Example 6 includes an antiglare layer 4 and an antireflection layer 9 and corresponds to the antiglare film 202. Also, the antiglare layer 4 of Example 6 has a phase separation structure. Comparative Examples 1, 3 to 6 include an antiglare layer having a fine particle dispersion structure. Comparative Examples 2 and 7 include an antiglare layer having a phase separation structure. Examples 7 to 13 and Comparative Example 7 include the same antiglare layer 4 as that of Example 1, and Example 1 is different from Example 1 in the thickness D of the base film 3, the retardation Re, and the integrated value (D × Re). As materials for the antiglare films according to Examples 1 to 13 and Comparative Examples 1 to 7, the materials of the following items (M1) to (M29) were used.

[0116] [Materials] (M1) Acrylic polymer having a polymerizable group: "ACA Z322M" manufactured by Daicel Corporation, solid content 40% by weight, solvent: 1-methoxy-2-propanol (MMPG) (boiling point 119°C) (M2) Cellulose acetate propionate: "CAP-482-20" manufactured by Eastman Chemical Company, degree of acetylation = 2.5%, degree of propionylation = 46%, polystyrene-reduced number average molecular weight 75,000 (M3) Silicone acrylate: "EB1360" manufactured by Daicel Ornex Co., Ltd. (M4) Silicone-based hard coat material: "AS-201S" manufactured by Tokushiki Co., Ltd. (M5) Urethane acrylate: "DCL-002" manufactured by Negami Kogyo Co., Ltd. (M6) Dipentaerythritol hexaacrylate: "DPHA" manufactured by Daicel Ornex Co., Ltd. (M7) Pentaerythritol tetraacrylate: "PETRA" manufactured by Daicel Ornex Co., Ltd. (M8) PMMA (polymethyl methacrylate) beads A: "SSX-105" manufactured by Sekisui Chemical Co., Ltd., average particle size 5 μm, refractive index 1.49 (M9) PMMA beads B: "SSX-103" manufactured by Sekisui Chemical Co., Ltd., average particle size 3 μm, refractive index 1.49 (M10) PMMA beads C: "SSX-115HXE" manufactured by Sekisui Chemical Co., Ltd., average particle size 3 μm, refractive index 1.49 (M11) Silica fine particles A: "KE-P250" manufactured by Nippon Shokubai Co., Ltd., average particle size 2.5 μm, refractive index 1.43 (M12) Silica fine particles B: "Silicia 310P" manufactured by Fuji Silysia Chemical Ltd., average particle size 2.7 μm (M13) Silica fine particles C: "Silohobic 100" manufactured by Fuji Silysia Chemical Ltd., average particle size 2.7 μm

[0117] (M14) Hollow silica-dispersed acrylic hard coat liquid: "P-5063" manufactured by JGC Catalysts and Chemicals Ltd., solid content 3% by weight (M15) Acrylic hard coat agent: "HX-MR4" manufactured by Kyoeisha Chemical Co., Ltd. (M16) Styrene beads: "SX-350H" manufactured by Soken Chemical & Engineering Co., Ltd. (M17) Fluorine-based compound A having a polymerizable group: "Phajent 602A" manufactured by Neos Co., Ltd., solvent: ethyl acetate, solid content concentration: 50% by mass (M18) Fluorine-based compound B having a polymerizable group: "KY-1203" manufactured by Shin-Etsu Chemical Co., Ltd., solid content concentration 20% by mass (M19) Photoinitiator A: "Omnirad184" manufactured by IGM Resin B.V. (M20) Photoinitiator B: "Omnirad907" manufactured by IGM Resin B.V. (M21) Polyethylene terephthalate (PET) film A: "Diafoil O321" manufactured by Mitsubishi Chemical Corporation, film thickness 50 μm (M22) Polyethylene terephthalate (PET) film B: "Diafoil O321" manufactured by Mitsubishi Rayon Co., Ltd., film thickness 75 μm (M23) Polyethylene terephthalate (PET) film C: "Diafoil O321" manufactured by Mitsubishi Rayon Co., Ltd., film thickness 100 μm (M24) Polyethylene terephthalate (PET) film D: "Diafoil O321" manufactured by Mitsubishi Rayon Co., Ltd., film thickness 125 μm (M25) Polyethylene terephthalate (PET) film E: "Cosmo Shine A4360" manufactured by Toyobo Co., Ltd., film thickness 50 μm (M26) Polyethylene terephthalate (PET) film F: "Cosmo Shine A4360" manufactured by Toyobo Co., Ltd., film thickness 75 μm (M27) Polyethylene terephthalate (PET) film G: "Lumirror U-403" manufactured by Toray Industries, Inc., film thickness 23 μm (M28) Polyethylene terephthalate (PET) film H: "Lumirror U-403" manufactured by Toray Industries, Inc., film thickness 50 μm (M29) Polyethylene terephthalate (PET) film I: "Lumirror U-403" manufactured by Toray Industries, Inc., film thickness 100 μm

[0118] [Example 1] (M1) 46 parts by weight of an acrylic polymer having a polymerizable group, (M2) 5 parts by weight of cellulose acetate propionate, (M5) 77 parts by weight of urethane acrylate, (M19) 1.5 parts by weight of photoinitiator A, (M20) 1.5 parts by weight of photoinitiator B, and (M17) 0.5 part by weight of a fluorine-based compound A having a polymerizable group were dissolved in a mixed solvent of 62 parts by weight of methyl ethyl ketone, 12 parts by weight of 1-butanol, 13 parts by weight of 1-methoxy-2-propanol, and 13 parts by weight of cyclohexanone to prepare a solution.

[0119] This solution was cast onto the substrate film (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 8 μm. Then, with a high-pressure mercury lamp, the integrated light amount was 200 mJ / cm2 and ultraviolet rays with a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) were irradiated onto the coating layer to subject the coating layer to ultraviolet curing treatment, thereby forming the antiglare layer 4. Thus, the antiglare film 2 of Example 1 was produced.

[0120] [Example 2] (M6) 50 parts by weight of dipentaerythritol hexaacrylate, (M7) 50 parts by weight of pentaerythritol tetraacrylate, (M8) 6.0 parts by weight of PMMA beads A, (M19) 2.0 parts by weight of photoinitiator A, (M20) 2.0 parts by weight of photoinitiator B, and 1.0 part by weight of fluorine-based compound A having a polymerizable group were dissolved in a mixed solvent of 146 parts by weight of methyl ethyl ketone and 59 parts by weight of 1-methoxy-2-propanol to prepare a solution.

[0121] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80°C for 1 minute to evaporate the solvent, thereby forming a coating layer with a thickness of about 5 μm. Then, the integrated light amount was 200 mJ / cm by a high-pressure mercury lamp 2 and ultraviolet rays with a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) were irradiated onto the coating layer to subject the coating layer to ultraviolet curing treatment, thereby forming the antiglare layer 104. Thus, the antiglare film 102 of Example 2 was produced.

[0122] [Example 3] (M1) 46 parts by weight of an acrylic polymer having a polymerizable group, (M2) 5 parts by weight of cellulose acetate propionate, (M5) 62 parts by weight of urethane acrylate, (M6) 15 parts by weight of dipentaerythritol hexaacrylate, (M19) 1.5 parts by weight of photoinitiator A, (M20) 1.5 parts by weight of photoinitiator B, and 0.5 part by weight of fluorine-based compound A having a polymerizable group were dissolved in a mixed solvent of 62 parts by weight of methyl ethyl ketone, 12 parts by weight of 1-butanol, 13 parts by weight of 1-methoxy-2-propanol, and 13 parts by weight of cyclohexanone to prepare a solution.

[0123] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 8 μm. Then, ultraviolet light with an integrated light quantity of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) was irradiated onto the coating layer to cure the coating layer by ultraviolet light and form an antiglare layer 4. Thereby, the antiglare film 2 of Example 3 was manufactured.

[0124] [Example 4] (M15) 100 parts by weight of an acrylic hard coat agent and (M16) 10 parts by weight of styrene beads A were mixed and dissolved in 30 parts by weight of methyl ethyl ketone to prepare a solution.

[0125] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 3 μm. Then, ultraviolet light with an integrated light quantity of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) was irradiated onto the coating layer to cure the coating layer by ultraviolet light and form an antiglare layer 104. Thereby, the antiglare film 102 of Example 4 was manufactured.

[0126] [Example 5] 50 parts by weight of an acrylic polymer having a polymerizable group (M1), 4 parts by weight of cellulose acetate propionate (M2), 76 parts by weight of urethane acrylate (M5), 1 part by weight of silicone acrylate (M3), 1.5 parts by weight of photoinitiator A (M19), and 1.5 parts by weight of photoinitiator B (M20) were dissolved in a mixed solvent of 176 parts by weight of methyl ethyl ketone and 28 parts by weight of 1-butanol to prepare a solution.

[0127] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 7 μm. Then, ultraviolet light with an integrated light quantity of 200 mJ / cm2 , ultraviolet light with a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) was irradiated onto the coating layer to subject the coating layer to ultraviolet curing treatment, thereby forming the antiglare layer 4. Thus, the antiglare film 2 of Example 5 was manufactured.

[0128] [Example 6] 46 parts by weight of an acrylic polymer having a polymerizable group (M1), 5 parts by weight of cellulose acetate propionate (M2), 77 parts by weight of urethane acrylate (M5), 1.5 parts by weight of photoinitiator A (M19), 1.5 parts by weight of photoinitiator B (M20), and 0.5 part by weight of a fluorine-based compound A having a polymerizable group (M17) were dissolved in a mixed solvent of 62 parts by weight of methyl ethyl ketone, 12 parts by weight of 1-butanol, 13 parts by weight of 1-methoxy-2-propanol, and 13 parts by weight of cyclohexanone to prepare a solution.

[0129] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80°C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 8 μm. Then, the integrated light quantity was 200 mJ / cm by a high-pressure mercury lamp 2 , and the peak illuminance was 400 mW / cm 2 (measurement value of 365 nm line) of ultraviolet light was irradiated onto the coating layer to subject the coating layer to ultraviolet curing treatment, thereby forming the antiglare layer 4. Thus, an intermediate film was obtained.

[0130] On the surface of the intermediate film where the antiglare layer 4 was formed, (M14) a hollow silica-dispersed acrylic hard coat liquid was cast using a wire bar, left in an oven at 70°C for 30 seconds, and the solvent was evaporated. Then, the integrated light quantity was 100 mJ / cm by a high-pressure mercury lamp 2 , and the peak illuminance was 400 mW / cm 2Ultraviolet light of (measured value of 365 nm line) was irradiated onto the coating layer, and a film was obtained in which a single-layer low refractive index layer 90 was formed as an antireflection layer 9 having a first structure on the surface of the antiglare layer 4. The type of wire bar was selected and the thickness of the antireflection layer 9 was set so that the spectral reflectance in the vicinity of 550 nm was the lowest when measuring the spectral reflectance spectrum of the film. Thereby, the antiglare film 202 of Example 6 was manufactured.

[0131] [Example 7] The antiglare film 2 of Example 7 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M22) PET film B. [Example 8] The antiglare film 2 of Example 8 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M23) PET film C. [Example 9] The antiglare film 2 of Example 9 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M24) PET film D. [Example 10] The antiglare film 2 of Example 10 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M25) PET film E.

[0132] [Example 11] The antiglare film 2 of Example 11 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M26) PET film F. [Example 12] The antiglare film 2 of Example 12 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M27) PET film G. [Example 13] The antiglare film of Example 13 was manufactured in the same manner as in Example 1, except that (M21) PET film A was changed to (M29) PET film I.

[0133] [Comparative Example 1] (M6) 50 parts by weight of dipentaerythritol hexaacrylate, (M7) 50 parts by weight of pentaerythritol tetraacrylate, (M9) 6.0 parts by weight of PMMA beads B, (M19) 2.0 parts by weight of photoinitiator A, (M20) 2.0 parts by weight of photoinitiator B, and 1.0 part by weight of fluorine-based compound A having a polymerizable group were dissolved in a mixed solvent of 146 parts by weight of methyl ethyl ketone and 59 parts by weight of 1-methoxy-2-propanol to prepare a solution.

[0134] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 5 μm. Then, ultraviolet light with an integrated light amount of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measured value of 365 nm line) was irradiated onto the coating layer to cure the coating layer by ultraviolet light and form an antiglare layer. Thereby, the antiglare film of Comparative Example 1 was manufactured.

[0135] [Comparative Example 2] (M1) 50 parts by weight of an acrylic polymer having a polymerizable group, (M2) 7 parts by weight of cellulose acetate propionate, (M5) 76 parts by weight of urethane acrylate, (M3) 1 part by weight of silicone acrylate, (M19) 1.5 parts by weight of photoinitiator A, and (M20) 1.5 parts by weight of photoinitiator B were dissolved in a mixed solvent of 176 parts by weight of methyl ethyl ketone and 28 parts by weight of 1-butanol to prepare a solution.

[0136] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coating layer with a thickness of about 7 μm. Then, ultraviolet light with an integrated light amount of 200 mJ / cm2 and a peak illuminance of 400 mW / cm 2 (measured value of 365 nm line) was irradiated onto the coating layer to cure the coating layer by ultraviolet light and form an antiglare layer. Thereby, the antiglare film of Comparative Example 2 was manufactured.

[0137] [Comparative Example 3] (M7) 100 parts by weight of pentaerythritol tetraacrylate, (M11) 14.0 parts by weight of silica fine particles, (M19) 2.0 parts by weight of photoinitiator A, (M20) 2.0 parts by weight of photoinitiator B, and (M18) 1.0 part by weight of a fluorine-based compound B having a polymerizable group were dissolved in a mixed solvent of 146 parts by weight of methyl ethyl ketone and 59 parts by weight of 1-methoxy-2-propanol to prepare a solution.

[0138] This solution was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coat layer with a thickness of about 5 μm. Then, ultraviolet rays with an integrated light amount of 200 mJ / cm2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) were irradiated onto the coat layer to perform ultraviolet curing treatment on the coat layer and form an antiglare layer. Thus, an antiglare film of Comparative Example 3 was manufactured.

[0139] [Comparative Example 4] A liquid obtained by mixing 100 parts by weight of (M15) acrylic hard coat agent A and 10 parts by weight of (M12) silica fine particles B was dissolved in 30 parts by weight of methyl ethyl ketone to prepare a solution.

[0140] This liquid was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80 °C for 1 minute to evaporate the solvent and form a coat layer with a thickness of about 4 μm. Then, ultraviolet rays with an integrated light amount of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) were irradiated onto the coat layer to perform ultraviolet curing treatment on the coat layer and form an antiglare layer. Thus, an antiglare film of Comparative Example 4 was manufactured.

[0141] [Comparative Example 5] A liquid obtained by mixing 100 parts by weight of (M15) acrylic hard coat agent A and 10 parts by weight of (M13) silica fine particles C was dissolved in 30 parts by weight of methyl ethyl ketone to prepare a solution.

[0142] This liquid was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80°C for 1 minute to evaporate the solvent and form a coating layer with a thickness of approximately 3 μm. Then, ultraviolet light with an integrated light quantity of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) was irradiated onto the coating layer to perform ultraviolet curing treatment on the coating layer and form an antiglare layer. Thus, the antiglare film of Comparative Example 5 was manufactured.

[0143] [Comparative Example 6] (M4) 260 parts by weight of a silicone-based hard coat material and (M10) 1.5 parts by weight of PMMA beads C were mixed to prepare a liquid. This liquid was cast onto (M21) PET film A using a wire bar, and then left in an oven at 80°C for 1 minute to evaporate the solvent and form a coating layer with a thickness of approximately 8 μm. Then, ultraviolet light with an integrated light quantity of 200 mJ / cm 2 and a peak illuminance of 400 mW / cm 2 (measurement value of 365 nm line) was irradiated onto the coating layer to perform ultraviolet curing treatment on the coating layer and form an antiglare layer. Thus, the antiglare film of Comparative Example 6 was manufactured.

[0144] Next, for each of the antiglare films of Examples 1 to 5 and Comparative Examples 1 to 6, based on the following conditions, Safc and Smr1 were measured to evaluate the state of rainbow unevenness. Also, for Example 1, Examples 7 to 13, and Comparative Example 7, retardation Re was measured, the integrated value (D × Re) was calculated, and the state of rainbow unevenness was evaluated.

[0145] Using an optical surface roughness meter "Bert Scan R5500G" manufactured by Hitachi High-Tech Science Corporation, based on the method compliant with ISO 25178, the fractal parameter Safc of the surface on the side opposite to the base film side of the antiglare layer of each antiglare film and the load area ratio Smr1 that divides the core part and the protruding peak part were measured by the following procedure.

[0146] [Settings of the optical surface roughness meter] Vibration isolation table: ON Objective lens: Nikon Corporation's "5x / 0.13 OFN25 WD 9.3" Light source: Nikon Corporation's "MODEL TE2-PS100W" Camera: Sony Corporation's full pixel readout type black and white camera module "XC-HR-57", 1 / 2'' CCD Upright microscope: Nikon Corporation's "ECLIPSE LV150" Fiber optic light source: Nikon Corporation's "LV-UEPI2"

[0147] [Settings on the measurement screen] Camera: Sony Corporation's full pixel readout type black and white camera module "XC-HR-57", 1 / 2'' CCD Objective lens: 5X Tube lens: 0.5X Body Zoom lens: No Relay Wavelength filter: 530white

[0148] [Measurement conditions] Measurement mode: Wave Field of view size: 640×480 Scan range: Start 5μm, Stop -10μm Average number of times: 1 Start measurement after auto lamp

[0149] [Analysis conditions] Complementation: Complete Surface correction: Fourth order [Measurement conditions for Safc] Filter: Gaussian (Short wavelength cut-off value λs: 50 [μm]) Analysis - ISOParam

[0150] [Measurement conditions for Smr1] Filter: Gaussian (Short wavelength cut-off value λs: 2.6 [μm]) Filter: Gaussian (Long wavelength cut-off value λc: 25 [μm]), High-pass image set as the main Analysis - ISOParam

[0151] [Retardation Re] The retardation Re of the base film of each anti-glare film was measured using "Photonic Lattice WPA-200" manufactured by Hishikari Co., Ltd., which is a two-dimensional birefringence evaluation system.

[0152] [Rainbow unevenness] Each anti-glare film was attached to the surface of a display of "JN-T280UHD-NS" manufactured by JAPANNEXT Co., Ltd., which is an LCD (resolution 4K (28 inches, 3840 dots × 2160 dots)). With the LCD driven to display a white screen, the rainbow unevenness was visually confirmed through a polarizing plate "PZ-2" manufactured by Kenis Co., Ltd. The rainbow unevenness at this time was evaluated according to the following five-level criteria. A higher evaluation value indicates a higher evaluation. 5: Rainbow unevenness cannot be confirmed from any angle of the surface. 4: Slight rainbow unevenness can be confirmed only when the surface is viewed from a specific angle. 3: Rainbow unevenness can be confirmed only when the surface is viewed from a specific angle. 2: Slight rainbow unevenness can be confirmed over the entire surface. 1: Rainbow unevenness comparable to the case without an anti-glare layer can be confirmed. The test results are shown in Table 1 and Table 2.

[0153]

Table 1

[0154]

Table 2

[0155] As shown in Table 1, the surfaces 4a and 104a of the antiglare layers 4 and 104 in Examples 1 to 6 have values in the range where the fractal parameter Safc is 0.02 or more when the short-wavelength cut-off value λs is set to 50 μm, and the surfaces have uneven shapes where the Smr1 is 14% or more when the long-wavelength cut-off value λc is set to 25 μm and the short-wavelength cut-off value λs is set to 2.6 μm. It was also confirmed that in Examples 1 to 6, rainbow unevenness was improved well. In contrast, in Comparative Examples 1 to 5, it was confirmed that the Safc on the surface of the antiglare layer was not in the range of 0.02 or more, and in Comparative Example 6, it was confirmed that the Smr1 on the surface of the antiglare layer was not in the range of 14% or more. It was also confirmed that in Comparative Examples 1 to 6, rainbow unevenness is more likely to occur compared to Examples 1 to 6.

[0156] Also, as shown in Table 2, it was confirmed that in Examples 1, 7 to 13, the integrated value (D × Re) is in the range of the formula 1. It was also confirmed that in Examples 1, 7 to 13, rainbow unevenness was improved relatively well. In contrast, in Comparative Example 7, although it has an antiglare layer equivalent to that of Example 1, it was confirmed that the integrated value (D × Re) is not in the range of the formula 1. It was also confirmed that in Comparative Example 7, rainbow unevenness is more likely to occur compared to Examples 1, 7 to 13.

[0157] (Disclosed item) Each of the following items is a disclosure of a preferred embodiment. [Item 1] A base film which is a biaxially stretched film satisfying the relationship shown in Formula 1 and having birefringence in the plane, and an antiglare layer disposed on top of the base film, comprising the surface of the antiglare layer opposite to the base film side has an uneven shape where the fractal parameter Safc, which is the short-wavelength cut-off value λs set to 50 μm, is in the range of 0.02 or more, and where the Smr1 is in the range of 14% or more when the long-wavelength cut-off value λc is set to 25 μm and the short-wavelength cut-off value λs is set to 2.6 μm, an antiglare film. [Formula 1] The thickness D (m) of the base film × retardation Re (m) ≥ 1.0 × 10 -10 (m 2 )

[0158] According to the above configuration, by setting the uneven shape of the surface of the antiglare layer to each of the above-mentioned values of Safc and Smr1, the uneven shape is formed to have a steep and high number density uneven distribution structure. Thereby, the incident light on the surface of the antiglare layer is scattered, and the reflection of external light on the surface of the antiglare layer is appropriately suppressed. In addition, an excellent antiglare effect can be obtained.

[0159] Further, by configuring the antiglare film to include an antiglare layer having the surface of the uneven shape and a base film satisfying Formula 1, the base film is formed of a biaxially stretched film to maintain sufficient mechanical strength, and an antiglare film having an excellent antiglare effect and an effect of preventing rainbow unevenness can be realized at low cost.

[0160] [Item 2] The base film is the antiglare film according to Item 1, including a polyester film.

[0161] According to the above configuration, an antiglare film having sufficient mechanical strength at a relatively low cost can be manufactured.

[0162] [Item 3] The surface of the antiglare layer on the side opposite to the base film side is the antiglare film according to Item 1 or 2, where Smr1 is a value in the range of 50% or less.

[0163] According to the above configuration, for example, the ratio of the convex portions of the uneven shape on the surface of the antiglare layer can be suppressed, and it is easy to maintain the mechanical strength of the antiglare film.

[0164] [Item 4] The Safc is the antiglare film according to any one of Items 1 to 3, where the value is in the range of 1.0 or less.

[0165] According to the above configuration, for example, even small characters displayed on the display surface with the antiglare film attached can be easily visible. Therefore, an excellent antiglare effect and image display performance can be obtained.

[0166] [Item 5] The antiglare film according to any one of Items 1 to 4, wherein the base film thickness D is a value in the range of 50 μm or more and 125 μm or less.

[0167] According to the above configuration, by using a base film having a certain base film thickness D, it is possible to facilitate the handling of materials during the production of the antiglare film and easily realize an antiglare film with excellent mechanical strength.

[0168] [Item 6] The antiglare film according to any one of Items 1 to 5, wherein the antiglare layer contains a plurality of resin components and has a phase separation structure of the plurality of resin components.

[0169] According to the above configuration, by using a phase separation structure, the concavo-convex shape of the surface of the antiglare layer can be formed to have a steep and high number density structure. Thereby, an excellent antiglare effect can be obtained.

[0170] [Item 7] The antiglare film according to any one of Items 1 to 6, wherein the antiglare layer has a fine particle dispersion structure including a matrix resin and a plurality of fine particles dispersed in the matrix resin.

[0171] According to the above configuration, by using a fine particle dispersion structure, the concavo-convex shape of the surface of the antiglare layer can be formed to have a steep and high number density structure. Thereby, an excellent antiglare effect can be obtained.

[0172] [Item 8] The antiglare film according to any one of Items 1 to 7, further comprising an antireflection layer disposed overlappingly on the side opposite to the base film side of the antiglare layer.

[0173] According to the above configuration, the optical properties of the antiglare film can be easily adjusted by using a low refractive index layer disposed on top of the antiglare layer.

[0174] [Item 9] An antiglare film according to any one of Items 1 to 8, and a polarizing plate disposed on top of the antiglare film, an optical member.

[0175] [Item 10] An antiglare film according to any one of Items 1 to 8, and a polarizing plate disposed on top of the film, and a display element disposed on top of the antiglare film and the polarizing plate, a display device.

[0176] Each configuration and their combinations in each embodiment are examples. Within the scope not departing from the gist of the present disclosure, addition, omission, substitution, and other changes of the configuration can be made as appropriate. The present disclosure is not limited by the embodiments, but only limited by the claims. Also, each aspect disclosed in this document can be combined with any other features disclosed in this document.

Explanation of Signs

[0177] 1, 20 Display device 2, 102, 202, 302, 402 Antiglare film 3 Substrate film 4, 104 Antiglare layer 4a, 104a Surface on the side opposite to the substrate film side of the antiglare layer 6 Polarizing plate 9 Antireflection layer 10 Optical member 15 Display element 40 Matrix resin 41 Fine particles

Claims

1. A base film which is a biaxially stretched film satisfying the relationship shown in Formula 1 and having a birefringence in the plane, and an antiglare layer disposed on top of the base film, and the surface of the antiglare layer opposite to the base film side has a fractal parameter Safc in the range of 0.02 or more when the cut-off value λs of short wavelengths is set to 50 μm, and has an uneven shape in which Smr1 is in the range of 14% or more when the cut-off value λc of long wavelengths is set to 25 μm and the cut-off value λs of short wavelengths is set to 2.6 μm. An antiglare film. [Formula 1] Substrate film thickness D (m) × Retardation Re (m) ≥ 1.0 × 10 －１０ (m ２ )

2. The antiglare film according to claim 1, wherein the base film includes a polyester film.

3. The antiglare film according to claim 1, wherein the surface of the antiglare layer opposite to the base film side has a value of Smr1 in the range of 50% or less.

4. The antiglare film according to claim 1, wherein the Safc is in the range of 1.0 or less.

5. The antiglare film according to claim 1, wherein the base film thickness D is in the range of 50 μm or more and 125 μm or less.

6. The antiglare film according to claim 1, wherein the antiglare layer includes a plurality of resin components and has a phase separation structure of the plurality of resin components.

7. The antiglare film according to claim 1, wherein the antiglare layer has a fine particle dispersion structure including a matrix resin and a plurality of fine particles dispersed in the matrix resin.

8. The antiglare film according to claim 1, further comprising an antireflection layer disposed on top of the surface of the antiglare layer opposite to the base film side.

9. An optical member comprising the antiglare film according to any one of claims 1 to 8, and a polarizing plate disposed on top of the antiglare film.

10. The antiglare film according to any one of claims 1 to 8, and a polarizing plate disposed on top of the film, and a display element disposed on top of the antiglare film and the polarizing plate. A display device.

Images