JP4134159B2 - Anti-glare film - Google Patents

Description

  The present invention is a type having a light source behind the screen such as various displays such as word processors, computers, televisions, in-vehicle instrument panels, liquid crystal displays, CRT displays, etc. It relates to film.

  As the film used on the surface of the display, because it is located on the outermost surface of the display, it can be directly touched by hands, wiped with various chemicals including synthetic detergents, or exposed to sunlight, Specific coding is applied to the base film in order to impart scratch resistance, chemical resistance, weather resistance and the like. Furthermore, in order to make the screen displayed on the display easy to see, various processings and processes as described below are performed in order to satisfy other required performances including anti-glare properties.

  For example, as disclosed in JP-A-59-151110, it is known to impart an antiglare effect by forming an uneven shape on the surface or mixing a matting agent in a hard coat. In these methods, the 60 degree glossiness can be lowered by increasing the haze degree, but conversely, in this method, the total light transmittance and the screen resolution may be lowered.

In addition, there is a method of adding a large amount of a fine powder light diffusing agent in an anti-glare film for the purpose of providing a high-precision, high haze, low gloss anti-glare effect for use in a color display for TET. Proposed. However, when the amount of the light diffusing agent added is increased, the coating suitability is deteriorated. As a result, there is a problem that streaks occur on the coated surface and the yield decreases. Furthermore, when such an antiglare film is applied to a polarizing plate, there is also a problem that the quality of the polarizing plate is deteriorated.
JP 59-151110 A

  The present invention provides an anti-glare film that allows a displayed character and other images to have a good resolution and a clear contrast without feeling dazzling when viewing an image on a display surface. The purpose is to do.

  In order to achieve the above object, the antiglare film according to the present invention comprises a transparent film and a total light transmittance of 85% or more, a haze of 3.0 to 35%, 60 degrees provided on the transparent film. An ionizing radiation curable resin layer having an optical characteristic with a glossiness of 90% or less, a surface centerline average roughness of 0.05 to 0.6 μm, and a surface roughness of a surface roughness of 5 to 200 μm. It is characterized by becoming.

  The anti-glare film according to the present invention has a transparent film and optical characteristics provided on the transparent film, with a total light transmittance of 85% or more, a haze of 3.0 to 35%, and a 60 degree gloss of 90% or less. And an ionizing radiation curable resin layer having a surface center line average roughness of 0.05 to 0.6 μm and a surface roughness of the surface irregularity pitch of 5 to 200 μm.

  The higher the total light transmittance, the better the display becomes brighter. However, in the present invention, it has been found that if it is 85% or more, it can be used practically without any problem.

  In order to obtain a good screen, the haze degree is in the range of 3.0 to 35%. When the haze degree exceeds the upper limit of the above range, the display screen looks whitish. On the other hand, when the haze degree is less than the lower limit, the glossiness increases and the antiglare effect decreases remarkably.

  The 60-degree glossiness is a value defined by reflection of light incident on the screen from the outside. When this value exceeds 90%, the dazzle increases and does not meet the object of the present invention.

  The numerical ranges of the pitch between the surface irregularities and the surface roughness are necessary conditions in the present invention for obtaining appropriate physical properties of the total light transmittance, the haze degree, and the 60 degree glossiness.

  The 60 degree glossiness can be measured based on the method defined in JIS Z8741 and reflected as shown in FIG. 2 by applying light P0 to the concavo-convex surface 2 at an incident angle of 60 degrees. This is a value representing the light receiving rate of the light P1 in%. On the other hand, the total light transmittance can be measured based on the method defined in JIS K6714. As shown in FIG. 2, the light transmittance of the transmitted light Q1 with respect to the reflected light Q0 is expressed in%. It is the value.

  In the present invention, as an anti-glare film particularly suitable for high-definition displays, it is preferable to control the surface center average roughness in the range of 0.05 to 0.4 μm among the above surface characteristics, More preferably, it is the range of 0.05-0.25. Here, “high definition” means an increase in the number of pixels per unit area, for example, an increase in 640 × 480 pixels to 800 × 600 pixels in a diagonal 26 cm panel.

  As the transparent film, for example, for the polarizing plate, a TAC (triacetyl cellulose film) mainly having a thickness of about 80 μm is often used, but it is appropriately selected from other known transparent plastic films. be able to. Examples of the transparent plastic film include the following. Polyester film, polyethylene film, polypropylene film, polyvinyl chloride film, acetylcellulose butyrate film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film and the like.

  As the resin for forming the hard coat layer, an acrylic urethane type ionizing radiation curable resin or the like is often used, and is a resin having a property of being cured by UV / EB, and TAC and Select one that is bonded and durable.

  As a light diffusing agent to be used for producing a high-Haze antireflection film, silica beads and acrylic beads of 0.5 to 5 μm are mainly used. In the case of a transparent resin that does not contain any light diffusing agent, the one that gives an optical function by the light diffusing agent may appear to be whitish on the contrary. It is desirable to mix a light diffusing agent to such an extent that the suitability is not lost. Further, when the light diffusing agent is kneaded into the ionizing radiation curable resin, the light diffusing agent is kneaded in an organic resin to coat the surface of the light diffusing agent, thereby ensuring transparency and wettability.

  The organic coating-treated light diffusing agent is dispersed in the ionizing radiation curable resin, and the content thereof is 10 parts by weight or less of the light diffusing agent with respect to 120 parts of the ionizing radiation curable resin. good.

  Furthermore, as a light diffusing agent, it is also effective to limit the particle size to exhibit good properties, and silica beads having an organic coating treatment, the particle size of which is 0.5 to 5 μm, Excellent effect.

  In the present invention, the ionizing radiation curable resin to be used is not particularly limited as long as it is a resin that is cured by ionizing radiation so-called UV / EB. Examples of the ultraviolet curable resin used together with the photosensitizer include an ultraviolet curable acrylic urethane resin, an ultraviolet curable polyester acrylate resin, and an ultraviolet curable epoxy acrylate resin.

  For example, the ultraviolet curable acrylic urethane-based resin can be obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and reacting the resulting product with an acrylate or methacrylate-based monomer having a hydroxyl group. As the photopolymerization initiator, benzophenone derivatives, acetophenone derivatives, anthraquinone derivatives and the like can be used alone or in combination.

  In some cases, the ionizing radiation curable resin may be appropriately selected and mixed with a component for improving film formation, such as an acrylic resin. In addition, a viscosity modifier, a solvent, etc. are blended to form a coating solution.

  As a coating means of ionizing radiation curable resin for forming a liquid composition mainly composed of ionizing radiation curable resin as described above on a base film, roll coating, reverse coating, gravure It can be carried out by a general coating method such as coating or slot orifice coating.

The coating amount is a coating amount after removing the solvent, and is 1 to 20 g / m ² , preferably 5 to 15 g / m ² .

  Next, the process of the present invention will be described. Applying the coating liquid mainly comprising an ionizing radiation curable resin to the transparent film, drying the solvent, and having flexibility, at least, a shaping film having fine irregularities on one side thereof, The dried coating surface is overlaid with an uneven surface, irradiated with ultraviolet rays through a transparent film or through a shaping film, and after curing the ionizing radiation curable resin, the shaping film is peeled off, Is transferred to the surface of the coat layer.

  The above coating liquid may be applied to the concavo-convex surface of the shaped film, and after drying the solvent of the coating liquid, the transparent film is overlaid, and thereafter the ultraviolet curing and peeling of the shaped film are performed as described above. Follow the same procedure.

  The film thus obtained has a performance as a scratch-resistant anti-glare film within the range of the following physical properties, and is extremely useful in practice.

In the present invention, the optical properties of the antiglare film can be further improved by further forming an antireflection layer made of a metal compound on the surface of the ionizing radiation curable resin layer. As such an antireflection layer, for example, a vapor deposition layer of a metal compound such as Al ₂ O ₃ , ZnO ₂ and MgF ₂ can be used. For example, an antireflection layer can be provided by sequentially providing a deposited layer of Al ₂ O _{3 of} about 1400 Å, ZnO _{2 of} about 2800 Å, and MgF ₂ 1400 Å.

Utilization of Shaped Film Next, another embodiment for making the film surface in a desired state when obtaining the present invention will be described.

  That is, in this embodiment, the surface of the shaped film is formed into a desired concavo-convex shape by further coating the resin on the shaped film, whereby the haze and gloss are low, and the antiglare effect is high in scratch resistance and chemical resistance. An antiglare film having excellent properties can be obtained.

  That is, in this method, a resin is applied to a matted film having a concavo-convex shape on the film surface to form a moldable film having the film surface improved to a desired concavo-convex shape. An irregular shape is formed on the ionizing radiation curable resin layer formed on the substrate, and the irregular shape is formed on the surface of the substrate film.

  In still another embodiment, a resin is applied to a matted film having a concavo-convex shape on the film surface to improve the film surface to a desired concavo-convex shape, and then the shaping film is applied with an ionizing radiation curable resin. Laminate on the ionizing radiation curable resin coating surface of the base film, and after irradiating ionizing radiation from the shaping sheet side or base side of the laminated film to cure the ionizing radiation curable resin, peel off the shaping film Thus, a predetermined antiglare film can be obtained.

  Next, in the above manufacturing method, the shaping film coated with the resin is a shaping film in which a concavo-convex shape is formed by coating a matted film with a resin added with a transparent resin or fine particles having a particle size of 0.5 to 10 μm. The ionizing radiation curable resin may be an ultraviolet curable resin, and the ionizing radiation may be ultraviolet light.

  Furthermore, the surface roughness of the shaped film is preferably a centerline average roughness (Ra) of 0.1 to 10 μm.

  And in said manufacturing method, after peeling a shaping film, irradiating ionizing radiation again and hardening an ionizing radiation curable resin, It is set as the anti-glare film which improved abrasion resistance and chemical resistance. it can.

  According to said method, the surface of a shaping | molding film can be made into the desired uneven | corrugated shape by coating a resin on the shaping | molding shaping | molding film base material further, Therefore, a haze and gloss are low, and an anti-glare effect High anti-glare film with excellent scratch resistance and chemical resistance can be produced.

  FIG. 3 is a schematic cross-sectional view showing an example of an antiglare film manufactured using a shaping film.

  4A is a cross-sectional view of a matted shaped film substrate, and FIG. 4B is a cross-sectional view of a shaped film in which a coating resin layer is provided on a matted shaped film substrate.

  5A to 5D are explanatory views when an antiglare film is produced using a shaping film provided with a coating resin layer.

  6A is a cross-sectional view of a shaped film produced by coating a matted shaped film substrate with a resin added with fine silica, and FIG. 6B is an anti-glare film produced using the shaped film of FIG. 6A. FIG.

Hereinafter, an example in the case of manufacturing the anti-glare film of this invention is shown.
First, as shown in FIG. 4A, using a film having good dimensional stability such as polyethylene terephthalate (hereinafter referred to as PET) film, an uneven shape is formed by embossing, sandblasting, etc., and matted. Make a mold film substrate.

  Next, as shown in FIG. 4B, a thermosetting resin or ionizing radiation curable resin is coated on the uneven surface of the shaped film substrate 11 to form a coating resin layer 12, and the uneven surface The shaping film 20 having a desired surface roughness is obtained by adjusting the roughness.

  When making an anti-glare film using the shaped film, a transparent, heat-resistant and dimensionally stable film such as a triacetyl cellulose film is used as the anti-glare film base material 14. The base material 14 is coated with an ionizing radiation curable resin to form an ionizing radiation curable resin layer 13a before curing as shown in FIG. 5B. Next, the uneven shape surface of the shaping film 20 is superimposed on the ionizing radiation curable resin layer 13a before the film is cured, and the uneven shape is formed on the ionizing radiation curable resin layer as shown in FIG. 5C. Mold. The ionizing radiation curable resin layer is cured by irradiating ionizing radiation from the shaping film side of the laminated sheet.

  After the ionizing radiation curable resin layer is sufficiently cured, as shown in FIG. 5B, the shaped film is peeled off from the laminated sheet to produce an antiglare film 10 having an uneven shape on the surface of the base film.

  When the ionizing radiation curable resin is cured with ionizing radiation, it can be cured by irradiation with ionizing radiation from the opposite side of the shaping film.

  Also, when using ultraviolet rays as ionizing radiation, after irradiating ultraviolet rays from the shaping film side and curing the ultraviolet curable resin, the shaping film is peeled off and irradiated again with ultraviolet rays to increase the crosslinking density, In some cases, the antiglare film has improved solvent resistance and scratch resistance.

  In addition, when making a moldable film, a matted mold film base material is coated with a resin added with fine particles having a particle size of 0.5 to 10 μm, and a moldable film as shown in FIG. 6A is produced. An antiglare film can be produced using this, and an antiglare film having a high antiglare effect as shown in FIG. 6B can be obtained.

  The base film used for the above-mentioned shaping film should just have dimensional stability and heat resistance, and can permeate ionizing radiation. Since ultraviolet rays such as a high-pressure mercury lamp are often used as ionizing radiation, a transparent PET film can be preferably used as the substrate film. A thickness of 10 to 200 [mu] m can be used, but the thickness is preferably about 25 [mu] m in consideration of the shapeable film production, reuse, cost, and the like. However, when an electron beam is used as the ionizing radiation, it may be a film that transmits the electron beam and does not necessarily need to be transparent.

  In general, thermosetting resin or ionizing radiation curable resin is used as the resin to be coated to adjust the roughness of the uneven shape of the shaping film, but it is applied to the surface of the antiglare film. The ionizing radiation curable resin can be used as long as it can form a predetermined uneven shape on the ionizing radiation curable resin layer without being softened or swollen, and is not particularly limited. Even thermoplastic resins can be used in combination with the type of ionizing radiation curable resin.

  The thermosetting resin that coats the moldable film is phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, amino argide resin, melamine-urea cocondensation There are resin, silicon resin, polysiloxane resin, cellulose acetate propionate, etc., and as necessary additives, curing agents such as crosslinking agents, polymerization initiators, polymerization accelerators, solvents, viscosity modifiers, extender pigments, etc. Added.

  As the curing agent, isocyanate is usually used for unsaturated polyester resins or polyurethane resins, and peroxides such as methyl ethyl ketone peroxide and radical initiators such as azoisobutyronitrile are often used for unsaturated polyesters. Furthermore, the isocyanate as a hardening | curing agent can use aliphatic or aromatic isocyanate more than bivalence.

  An ionizing radiation curable resin is also used as the coating resin. Since the ionizing radiation curable resin is also used for producing an antiglare film, it will be described in detail in the section of the antiglare film.

  The base film used for the antiglare film may be any film that is transparent, has dimensional stability and heat resistance, and transmits ionizing radiation. When used for display devices such as LCD, CRT, LED, etc., a triacetyl cellulose film is often used.

  When curing an ionizing radiation curable resin applied to a base film, ultraviolet rays such as a high-pressure mercury lamp are often used as ionizing radiation. Therefore, a film that transmits ultraviolet rays is usually used, but an ionizing radiation curable resin layer is used. In the case of curing by irradiating ultraviolet rays only from the shaping film side, it is not always necessary to transmit the ultraviolet rays.

  A thickness of 10 to 200 [mu] m can be used, but about 80 [mu] m is desirable in consideration of workability and cost.

  As the ionizing radiation curable resin for forming an uneven shape on the surface of the antiglare film, an ultraviolet curable resin or an electron beam curable resin is usually used.

  As ionizing radiation curable resin, (meth) acryloyl group, (meth) acryloyloxy group ((meth) acryloyl is used in the meaning of acryloyl or methacryloyl in the molecule, and the following (meth) has the same meaning. ) And the like, or a composition in which prepolymers, oligomers, and / or monomers having an epoxy group are appropriately mixed.

  Examples of these prepolymers and oligomers include acrylates such as urethane (meth) acrylate, polyester (meth) acrylate, and epoxy (meth) acrylate, silicon resins such as siloxane, unsaturated polyester, and epoxy.

  Examples of monomers include styrene monomers such as styrene and α-methylstyrene, methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, pentaerythritol (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, dipentaerythritol penta (meth) acrylate, trimethylolpropane tri (meth) acrylate, and / or a polyol compound having two or more thiol groups in the molecule, for example, trimethylolpropane trithioglycolate , Trimethylolpropane trithiopropylate, pentaerythritol tetrathioglycol and the like.

  If necessary, the above compounds are used alone or in combination of two or more, but in order to impart ordinary coating suitability to the resin composition, 5% by weight or more of the prepolymer or oligomer is added to the monomer. And / or polythiol is preferably 95% by weight or less.

  If the flexibility of the cured product is required when selecting the monomer, the amount of the monomer may be reduced or a monofunctional or bifunctional acrylate monomer may be used as long as there is no hindrance in coating suitability. Use a structure with a relatively low crosslinking density.

  In addition, when the cured product is required to have heat resistance, hardness, solvent resistance, etc., the amount of monomer is increased within a range that does not hinder coating suitability, or an acrylate monomer having three or more functionalities. It is preferable to use a high crosslink density structure.

  A monofunctional monomer and a trifunctional or higher monomer can be mixed to adjust the coating suitability and the physical properties of the cured product.

  Examples of the monofunctional acrylate monomer as described above include 2-hydroxy acrylate, 2-hexyl acrylate, phenoxyethyl acrylate, and the like.

  Examples of bifunctional acrylate monomers include ethylene glycol diacrylate and 1,6-hexanediol diacrylate. Examples of trifunctional acrylate monomers include trimethylolpropane triacrylate, pentaerythritol tetraacrylate, and pentaerythritol triacrylate. And dipentaerythritol hexaacrylate.

  When the ionizing radiation curable resin is cured with ultraviolet rays, it is necessary to use a transparent resin. In addition, as a photopolymerization initiator in the ionizing radiation curable resin composition, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetramethylmeuram monosulfide, thioxanthones, and / or photosensitization. As the agent, n-butylamine, triethylamine, tri-n-butylphosphine and the like can be mixed and used.

  In the present invention, ionizing radiation irradiation is used as a method for completely curing a resin composition containing an ionizing radiation curable resin applied to an antiglare film substrate.

  Overlay the shaping film on the resin layer formed on the base material to mold the uneven shape on the resin layer, and then completely cure the resin layer by irradiating with ionizing radiation such as ultraviolet rays and electron beams. .

  When ultraviolet rays are used as the ionizing radiation, if the curing is insufficient by a single irradiation from above the shaping film, the shaping layer is peeled off, and then the ultraviolet rays are irradiated again to completely cure the resin layer.

  As the ionizing radiation irradiation apparatus, an ultraviolet irradiation apparatus or an electron beam irradiation apparatus is usually used.

  For example, as an ultraviolet irradiation device, a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a black light, or a metal halide lamp is used.

  As an electron beam source, various electron beam accelerators such as a Cochloftwald type, a bandegraph type, a resonant transformer type, an insulated core transformer type or a linear type, a dynamitron type, a high frequency type, etc. are used. Irradiate electrons with energy of ˜300 KeV. The irradiation dose is usually about 0.5 to 30 KGy (kilo gray).

Production of Transparent Protective Substrate Comprising Antiglare Film and Polarizing Plate A conventional transparent protective substrate having antiglare property is provided with a coating film made of a resin composition containing amorphous silica on the surface. This amorphous silica is obtained by applying a coating with amorphous silica to the surface of the transparent substrate in order to impart antiglare properties to the surface of the transparent protective substrate. In order to impart antiglare properties, silica is blended around 2 parts by weight with respect to 100 parts by weight of the resin. When a triacetate film is used for the transparent substrate, when the saponification treatment is performed on the coating film containing silica for the purpose of improving adhesion and preventing static charge, the value indicating the haze value of the obtained triacetate film is increased. The film had poor resolution, contrast, and transparency. Here, the haze value is a value expressed by diffuse transmittance / total light transmittance, and indicates a diffused ratio of transmitted light.

  Therefore, in this embodiment, the method for producing a transparent protective substrate having excellent antiglare properties and at the same time, excellent transparency, resolution, contrast, surface hardness and solvent resistance, and the manufacturing method thereof are obtained. And a polarizing plate using the transparent protective substrate.

  Furthermore, in this embodiment, in the case where an acetylcellulose-based film is used as the transparent substrate, a method for producing a transparent protective substrate, in which the haze value, contrast, and transparency are not deteriorated even by saponification treatment, the production method thereof The obtained transparent protective substrate and a polarizing plate using the transparent protective substrate are provided.

  In a preferred embodiment of this embodiment, a coating composition consisting essentially of resin beads having a refractive index of 1.40 to 1.60 and an ionizing radiation curable resin composition is applied onto a transparent substrate, A transparent protective substrate having an antiglare film can be obtained by irradiating ionizing radiation onto the uncured coating film of the coating composition to cure the coating film of the coating composition.

  The transparent substrate includes a triacetyl cellulose film, a diacetyl cellulose film, an acetate butyrate cellulose film, a polyether sulfone film, a polyacrylic resin film, a polyurethane resin film, a polyester film, a polycarbonate film, a polysulfone film, and a polyether film. A trimethylpentene film, a polyetherketone film, a (meth) acrylonitrile film, and the like can be used. In particular, a triacetylcellulose film is preferably used because it is excellent in transparency.

  The film-forming component used in the ionizing radiation curable resin composition is preferably one having an acrylate functional group, for example, a relatively low molecular weight polyester resin, polyether resin, acrylic resin, epoxy resin, urethane resin. , Oligomers or prepolymers such as (meth) acrylates of polyfunctional compounds such as alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, polyhydric alcohols and the like, and reactive diluents such as ethyl (meth) acrylate, ethylhexyl (meth) Monofunctional monomers such as acrylate, styrene, methylstyrene, N-vinylpyrrolidone and polyfunctional monomers such as trimethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropyleneglycol 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 Those containing a relatively large amount can be used.

  Particularly preferably, a mixture of polyester acrylate and polyurethane acrylate is used. The reason is that polyester acrylate is very hard and suitable for obtaining a hard coat, but polyester acrylate alone has low impact and is brittle. In order to give the properties, polyurethane acrylate is used in combination. The blending ratio of polyurethane acrylate with respect to 100 parts by weight of polyester acrylate is 30 parts by weight or less. If this value is exceeded, the coating film is too soft and the hardness is lost.

  Further, in order to make the ionizing radiation curable resin composition into an ultraviolet curable resin composition, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetra Methyl thiuram monosulfide, thioxanthones, and n-butylamine, triethylamine, tri-n-butylphosphine and the like can be used as a photosensitizer. In particular, in the present invention, it is preferable to mix urethane acrylate as an oligomer and dipentaerythritol hexaacrylate as a monomer.

  The ionizing radiation curable resin composition is preferably mixed with resin beads having a refractive index of 1.40 to 1.60 in order to impart antiglare properties. The reason for limiting the refractive index of the resin beads to such a value is that the refractive index of the ionizing radiation curable resin is usually 1.40 to 1.50, so that the refractive index is as close as possible to the refractive index of the ionizing radiation curable resin. This is because if resin beads having a rate are selected, the transparency of the coating film is not impaired and the antiglare property can be increased. By the way, resin beads having a refractive index close to that of the ionizing radiation curable resin are shown below.

Resin Bead Name Refractive Index MMA (Polymethyl Methacrylate) Bead 1.49
Polycarbonate beads 1.58
Polystyrene beads 1.50
Polyacryl styrene beads 1.57
Polyvinyl chloride beads 1.54
The particle diameter of these resin beads is preferably 3 to 8 μm, and 2 to 10 parts by weight, usually about 4 parts by weight, is used with respect to 100 parts by weight of the resin.

  When such resin beads are mixed in this coating composition, it is necessary to stir and disperse well the resin beads precipitated on the bottom of the container when using the coating. In order to eliminate such inconvenience, silica beads having a particle diameter of 0.5 μm or less, preferably 0.1 to 0.25 μm may be included in the coating composition as an anti-settling agent for resin beads. Note that the more silica beads are added, the more effective the prevention of sedimentation of the organic filler is, but it adversely affects the transparency of the coating film. Therefore, it is preferable that the amount is less than 0.1 parts by weight, which is a range that can prevent sedimentation, without impairing the transparency of the coating film with respect to 100 parts by weight of the resin.

  Furthermore, an antistatic agent may be added to the coating composition for forming a hard coat coating film having an antiglare property used in the present invention for the purpose of preventing the coating film from being charged. As the antistatic agent, a metal filler, tin oxide, indium oxide, or the like can be used.

  The coating composition for forming the antiglare film used in the present invention may contain 10 parts by weight or more and 100 parts by weight or less of the solvent-drying resin with respect to 100 parts by weight of the resin. As the solvent-drying resin, a thermoplastic resin is mainly used. In particular, when a mixture of polyester acrylate and polyurethane acrylate is used in the ionizing radiation curable resin composition, polymethyl methacrylate acrylate, polybutyl methacrylate acrylate, or cellulose acetate propionate is suitable for the solvent-drying resin used. Used for.

  The reason why the solvent-drying resin is included in the ionizing radiation curable resin composition in the present invention will be described below. When the coating material used in the present invention is applied to a transparent substrate with, for example, a roll coater having a metering roll, for example, a slit reverse coater, the solvent-drying resin is essentially made from the ionizing radiation curable resin composition as described above. This is because when it is included in the constituted coating composition, coating film defects do not occur during roll coating.

  FIG. 7 shows a specific example of slit reverse coating. In this coating apparatus, the base material is transferred to the backup roll 102, and the composition is applied onto the base material by the nozzle coating apparatus 101. In part B, the coating composition is adjusted by the metering roll 103, and the unnecessary composition is removed by the doctor 104.

  The coating composition essentially consisting of such an ionizing radiation curable resin composition can be cured by an ordinary ionizing radiation curable resin composition curing method, that is, by irradiation with an electron beam or ultraviolet rays. For example, in the case of electron beam curing, 50 to 1000 KeV emitted from various electron beam accelerators such as a Cockloft Walton type, a bandegraph type, a resonant transformation type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type, Preferably, an electron beam or the like having an energy of 100 to 300 KeV is used, and in the case of ultraviolet curing, ultraviolet rays emitted from light rays such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp can be used. .

  Moreover, this invention makes it a polarizing plate by laminating | stacking a polarizing element on the transparent protective substrate which formed the hard-coat coating film which has the anti-glare property manufactured as mentioned above. For this polarizing element, a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer saponified film, or the like that is dyed with iodine or a dye and stretched can be used. In order to increase adhesion and to prevent static electricity during the laminating process, when the transparent protective substrate is a triacetyl cellulose film, for example, the triacetyl cellulose film is saponified. This saponification treatment may be performed either before or after the hard coat is applied to the triacetyl cellulose film.

Production Example of Polarizing Plate Next, a preferred embodiment for improving the durability of the liquid crystal cell by adjusting the moisture permeability of a polarizing plate provided on the surface of the liquid crystal cell, particularly a sheet used for the polarizing plate will be described.

  In recent years, LCDs, CRTs, plasma displays, and other displays have made remarkable progress. In particular, LCDs have become more demanding of quality in terms of size, color, and definition, and require polarizing plates with excellent durability. I came. As a polarizing plate for an LCD with higher definition, a cellulose triacetate sheet (hereinafter referred to as a TAC sheet) excellent in light transmittance and adhesion to other materials has been used.

  Conventionally, the transparent sheet used for the polarizing plate is a TAC sheet having excellent optical functions such as haze, reflectance, light transmittance, and image clarity, and the antiglare layer further considers adhesiveness to the transparent sheet. In order to satisfy the scratch resistance, the friction resistance, etc., those having an ionizing radiation curable resin as a binder have been selected and used.

  TAC sheets used in conventional polarizing plates have excellent optical properties, but have a disadvantage that they are inferior in moisture resistance compared to other plastic sheets such as polyester, and have high moisture permeability. is there. Therefore, the polarizing plate using the TAC sheet is inferior in durability that the sheet itself is degraded by hydrolysis due to moisture in the environment, or the function of the polarizer made of polyvinyl alcohol is lowered by the transmitted moisture. There was a problem.

  Therefore, in this embodiment, a TAC sheet having excellent optical properties is used for the polarizing plate to provide moisture resistance, preventing hydrolysis thereof, and a polarizer made of polyvinyl alcohol has excellent durability that does not cause functional deterioration. A polarizing plate is provided.

In order to achieve the above object, in this aspect, at least one sheet is defined in JIS Z0208 in a polarizing plate configured by providing a polarizer between two transparent sheets. According to the moisture-proof packaging material moisture permeability test method, 500 g / m ² · 24 hrs. It consists of the following moisture permeability.

  The transparent sheet is a cellulose triacetate sheet, the hard coat layer is provided on the sheet surface, and the thickness of the hard coat layer formed of pentaerythritol triacrylate and a polymerization initiator is 3 μm. It is a polarizing plate which is -20 micrometers.

  As shown in FIG. 8, the antiglare polarizing plate AB of this embodiment has polyvinyl chloride on the other surface of the antiglare sheet SB provided with the antiglare film 3b according to the present invention on at least one surface of the transparent sheet 201. A polarizer 202 made of alcohol and a transparent sheet 201 are sequentially laminated.

The moisture permeability of the transparent sheet provided with the antiglare film layer 203b is 500 g / m ² · 24 hrs. (Hereinafter, the moisture permeability is simply described as g / m ² ).

  Examples of the transparent sheet used in this embodiment include a stretched polyester sheet, a polycarbonate sheet, a polymethyl methacrylate sheet, a polyvinyl chloride sheet, a saponified ethylene / vinyl acetate copolymer sheet, and a polymethylpentene sheet. Preferably, it is a necessary condition that the optical function is excellent in haze, reflectance, light transmittance, image clarity, and there is no unevenness in the thickness of the sheet, and it is a necessary condition, and is manufactured by a casting method. 80 μm TAC sheet is often used.

  A polarizer composed of a polyvinyl alcohol film is a laminate of two 20 μm thick films that are uniaxially stretched and have polarization properties due to molecular orientation in one direction. The liquid crystal cell for LCD is configured by sealing a liquid crystal cell provided with a color filter in the middle of two glass plates with a transparent electrode, and laminating a polarizing plate on each outer surface via an adhesive layer. .

  For example, as shown in FIG. 8, the polarizing plate is configured by interposing a polarizer 202 between the transparent sheet 201 and the antiglare sheet SB provided with the antiglare hard coat layer 203b.

  As the binder of the antiglare hard coat layer 203b provided on the surface of the transparent sheet 201, an ultraviolet curable resin that is easy to handle is selected as a binder among ionizing radiation curable resins in consideration of adhesion to the sheet and scratch resistance. .

  As the ionizing radiation curable resin, a composition in which a prepolymer, an oligomer, and / or a monomer having a polymerizable unsaturated bond or an epoxy group in the molecule is appropriately mixed is used.

  These resin systems include urethane acrylates, unremethacrylates, polyester acrylates, polyester methacrylates, epoxy acrylates, epoxy methacrylates and other acrylates, silicone resins such as methacrylates and siloxanes, and polyester epoxies.

  The prepolymer and oligomer include unsaturated polyesters such as a condensate of unsaturated dicarboxylic acid and polyhydric alcohol.

  Monomers include polyfunctional acrylate monomers such as pentaerythritol triacrylate, trimethylolpropane triacrylate, pentaerythritol hexaacrylate, styrene, α-methylstyrene, methyl acrylate, methyl methacrylate, acrylamide, Examples include ethylene glycol diacrylate and trimethylolpropane trithioglycolate.

  Particularly when UV curing is performed, the ionizing radiation curable resin composition is subjected to photopolymerization initiators such as acetophenones, benzophenones, Michler benzoylbenzoate, thioxanthones, and / or triethylamine, tri-amine as photosensitizers. A mixture of n-butylphosphine and the like can also be used.

  A surfactant having an antistatic effect can be included in the coating solution for the antiglare hard coat layer for the purpose of preventing dust from adhering to the antiglare hard coat layer of the polarizing plate used on the surface of the liquid crystal cell. .

  The surfactant is appropriately selected from a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant.

  For the purpose of improving the scratch resistance of the antiglare hard coat layer of the polarizing plate used on the surface of the liquid crystal cell, it is appropriately selected from hydrocarbons, fatty acids, fatty acid esters, amides, amines, silicones, etc., which are lubricants. It can also be added.

  The light diffusing agent is appropriately selected from organic fine particles such as silica, calcium carbonate, precipitated barium sulfate, aluminum hydroxide powder, polyethylene particles, polymethyl methacrylate particles, polycarbonate particles, used. In particular, silica powder has a high transmittance with respect to ultraviolet rays and is excellent without inhibiting the curing of the ultraviolet curable resin as a binder.

  The thickness of the antiglare hard coat layer capable of obtaining a desired moisture permeability is 3 μm or more, preferably 5 μm or more and 20 μm or less.

  When the thickness of the coating layer is 3 μm or less, it is impossible to cover the defects of the protrusions of the original fabric. When the thickness is 20 μm or more, curling becomes serious and mechanical suitability is deteriorated. 8 μm.

  The above compounds and additives are used alone or in combination of two or more as required. The resin varnish has a viscosity of 200 to 1500 centipoise suitable for a reverse roll coating method for smoothing the coated surface, and has a solid content of 60 to provide leveling properties after coating and cover fine protrusions. % Or more is good. And in order to satisfy said conditions, what adjusted the viscosity by adding a hardening | curing agent and a solvent to 100 parts of pentaerythritol triacrylates from the said monomer is preferable.

  Depending on the amount of light diffusing agent used in the antiglare hard coat layer, the water vapor transmission rate may be increased. In some cases, the transparent layer and the antiglare layer are formed on the same surface of the sheet with an ionizing radiation curable resin varnish. What has a desired water vapor transmission rate can also be provided by two-layer coating with a hard-coat layer.

  The coating method for forming the antiglare hard coat layer is determined by the properties and coating amount of the coating solution, but in order to obtain surface smoothness, from direct or reverse roll coating, bar coating, gravure coating, etc. It is performed at a viscosity of 200 to 1500 centipoise, which is a viscosity suitable for flowability, by which the coated surface is flowed before curing after coating to obtain a smooth uniform surface.

The polarizing plate of the present invention is as shown in FIGS. That is,
(1) The figure which laminated | stacked in order the anti-glare sheet | seat SB which provided the anti-glare hard-coat layer (anti-glare film layer) 203b in the transparent sheet 201, the polarizer 202, and the transparent sheet 201 which does not provide a hard-coat layer. Antiglare polarizing plate AB shown in FIG.

(2) A moisture-proof hard coat layer 203c as shown in FIG. 9 is formed by sequentially stacking a moisture-proof sheet SC provided on the transparent sheet 201, a polarizer 202, and a transparent sheet 201 without a hard coat layer. Polarizing plate AC.

(3) A polarizing plate AA in which a transparent sheet 201 without a hard coat layer as shown in FIG. 10, a polarizer 202, and a transparent sheet 201 without a hard coat layer are sequentially laminated.

(4) The transparent sheet may be a polyethylene terephthalate sheet that is slightly inferior in terms of optical and surface strength, but is superior in moisture resistance. That is, the moisture-proof polarizing plate AD shown in FIG. 11 in which a transparent sheet 201, a polarizer 202, and a moisture-proof transparent sheet (polyethylene terephthalate) 1D not provided with a hard coat layer are sequentially laminated.

According to the required degree of durability, the above-mentioned polarizing plate is appropriately selected and the liquid crystal 4 is used to constitute a “liquid crystal cell” for LCD. That is,
(1) “Liquid crystal cell” constituted by using a polarizing plate AA in which a hard coat layer is not provided on a polarizing plate on both sides as shown by 4AA in FIG. 12A.

(2) “Anti-glare liquid crystal cell” for LCD, which comprises an anti-glare polarizing plate AB on one surface as shown in 4AB of FIG. 12B and a polarizing plate AA on which the hard coat layer is not provided on the other surface.

(3) An anti-glare polarizing plate AB provided with an anti-glare hard coat layer on one polarizing plate as shown by 4BC in FIG. 12C, and a moisture-proof polarizing plate AC provided with a moisture-proof hard coat layer on the other surface are provided. Three types of “anti-glare and moisture-proof liquid crystal cell” for LCD, in which both transparent sheets 201 are provided with a coating layer of an ionizing radiation curable resin, can be configured.

(4) Further, as shown in 4BD of FIG. 12D, a hard coat layer is not provided on one polarizing plate, but a transparent moisture-proof polarizing plate AD formed from a moisture-proof polyethylene terephthalate sheet 1D and on the other surface An “anti-glare and moisture-proof liquid crystal cell” for LCD can be constituted by the anti-glare polarizing plate AB.

As described above, the polarizing plate provided with the antiglare hard coat layer made of the ionizing radiation curable resin formed on the transparent sheet surface has a moisture permeability of 500 g / m by the antiglare hard coat layer and the moisture-proof hard coat layer. ^It is composed of ² or less.

  Further, it prevents moisture from the outside from penetrating into the transparent sheet, prevents chemical changes such as hydrolysis of the transparent sheet, and prevents the deterioration of the liquid crystal function of the polarizer.

Example 1
An ultraviolet curable resin 2 having the following composition was applied to a triacetyl cellulose film [TAC 80 μml (manufactured by Fuji Photo Film Co., Ltd., FT-UV-80)] by a roll coating method so as to be 7 to 8 g / m ² .

100 parts by weight of polyfunctional acrylate (pentaerythritol triacrylate)
Cellulose acetate propionate 1.2 parts by weight Benzophenone 4 parts by weight Irgacure 4 parts by weight (toluene)
Next, after drying the solvent, matted PET (Ra: 0.47, Sm: 47.5) is laminated as a shaping film, and as an ultraviolet curing condition, a mercury lamp 160W × 2 lamp is irradiated from a distance of 15 cm, The ultraviolet curable resin was cured under conditions of 10 m / min. Further, the shaped film was peeled off to obtain an antiglare film.

The measurement results of the optical properties of the film are as follows.
Total light transmittance 87.5%
Haze 28.9%
60 ° gloss 25.6% or less Centerline average roughness Ra 0.42 μm
Uneven pitch Sm 70.8μm
The antiglare film thus obtained was free from glare due to light reflection, and had excellent image sharpness.

  Optical property values, surface roughness measuring methods and measuring instruments are as follows. The same applies to the embodiments described later.

Haze (cloudiness) <Haze>: JIS K6714 / Toyo Seiki direct reading haze meter Total light transmittance: JIS K6714 / Toyo Seiki direct reading haze meter Gloss <Gross>: JIS K8741 / Murakami Color Research Laboratory GM -3D
Centerline average roughness <Ra>: JIS B0601
Average spacing of irregularities <Sm>: Kosaka Laboratory SEF-30.

Example 2
Triacetyl cellulose film (TAC 80 μm (FT-UV-80 manufactured by Fuji Photo Film Co., Ltd.)) Polyester film 75 μm (T-60 manufactured by Toray Industries, Inc.), light diffusion with respect to 100 parts by weight of UV curable resin A liquid containing 5 parts by weight of an agent (silica beads) was applied by a roll coating method to 7 to 8 g / m ² . After the solvent was dried, matted PET (Ra: 0.46, Sm: 45.0) was laminated as a shaping film, and mercury lamps 160W × 2 lamps were used as UV curing conditions, from a distance of 15 cm to 10 m / min. After curing the ultraviolet curable resin under the conditions, the shaping film was peeled off to obtain an antiglare film.

The measurement results of the optical properties of the film are as follows.
Total light transmittance 87.0%
Haze 30.1%
60 ° glossiness 24.6%
Surface roughness 46μm
Uneven pitch 70.7μm
As in the case of Example 1, an antiglare film capable of preventing glare due to light reflection and clearly displaying an image was obtained.

Comparative Example 1
AG30 manufactured by Nitto Denko Corporation has optical characteristics of total light transmittance of 87%, HAZE of 3.5%, 60 degree gloss of 110%, surface center line average roughness of 0.2 μm, and pitch between surface irregularities of 170 μm. It was a hard coat film having a surface roughness, and had a glare on the surface.

  Antiglare films of the following examples were produced according to the following production conditions.

Example 3
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 2.7
Benzophenone 2.7
Particle: Material: Silica coupling treated silica 4.2
Size: Average particle size 3μm
Additive: Ether-modified silicone 0.1
Diluting solvent: Toluene 84.8
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 5 g / m ² (DRY)
(4) Drying Drying temperature: about 70 ° C
Drying time: about 1 min
(5) Molding film None (6) UV irradiation Lamp used: High-pressure mercury lamp (made by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 4
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 2.7
Benzophenone 2.7
Particle: Material: Acrylic 2.8
Size: Average particle size 5μm
Additive: Ether-modified silicone 0.1
Diluting solvent: Toluene 94.8
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 5 g / m ³ (DRY)
(4) Drying Drying temperature: about 80 ° C
Drying time: about 1 min
(5) Molding film None (6) UV irradiation Lamp used: High-pressure mercury lamp (made by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 5
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 2.7
Benzophenone 2.7
Particle: Material: Silica coupling treated silica 3.8
Size: Average particle size 1.5μm
Additive: Ether-modified silicone 0.1
Diluting solvent: Toluene 104.4
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 5 g / m ³ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Molding film None (6) UV irradiation Lamp used: High-pressure mercury lamp (made by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 6
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 2.7
Benzophenone 2.7
Particle: Material: Silica coupling treated silica 5.6
Size: Average particle size 1.5μm
Additive: Ether-modified silicone 0.1
Diluting solvent: Toluene 106.4
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 5 g / m ³ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Molding film None (6) UV irradiation Lamp used: High-pressure mercury lamp (made by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 7
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.3
Benzophenone 3.3
Particle: Material: Silane coupling-treated silica 26.4
Size: Average particle size 1μm
Additive: Ether-modified silicone 0.1
Diluting solvent: Toluene 128.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 5 g / m ³ (DRY).

Example 8
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Konica Corporation
Product name: KC80UVS
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ³ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Shaped film Material: PET (polyester) (matte kneaded)
Thickness: 26μm
Manufacturer: Diafoil Hoechst Co., Ltd.
Product name: E-130
(6) UV irradiation Lamp used: High pressure mercury lamp (manufactured by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 9
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ³ (DRY)
(4) Drying Drying temperature: about 70 ° C
Drying time: about 1 min
(5) Shaped film Material: PET (polyester) (matte kneaded)
Thickness: 26μm
Manufacturer: Diafoil Hoechst Co., Ltd.
Product name: E-130
(6) UV irradiation Lamp used: High pressure mercury lamp (manufactured by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 10
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Konica Corporation
Product name: KC80UVS
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ₃ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Shaped film Material: PET (polyester)
Thickness: 25μm
Manufacturer: Toray Industries, Inc.
Product Name: E-06
(6) UV irradiation Lamp used: High pressure mercury lamp (manufactured by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 11
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Konica Corporation
Product name: KC80UVS
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ³ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Shaped film Material: PET (polyester) (matte kneaded)
Thickness: 25μm
Manufacturer: Unitika Ltd.
Product name: PTH-25
(6) UV irradiation Lamp used: High pressure mercury lamp (manufactured by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Example 12
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Bentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ³ (DRY)
(4) Drying Drying temperature: about 40 ° C
Drying time: about 1 min
(5) Shaped film Base material: Material: PET
Thickness: 26μm
Manufacturer: Diafoil Hoechst Co., Ltd.
Product name: E-130
Coating resin: cellulose acetate propionate 100.0 parts by weight
Xylene diitocyanate 22.0
Silicone 1.5
MEK 490.3
Ethyl acetate 7.4
Toluene 414.1
Anon 416.8
Coating: Coating method: Matrix Bath Method
Coating thickness: 3 g / m ³ (DRY)
Drying: Temperature: 80 ° C
Time: about 1 min
Incubation: 70 ° C for 5 days (6) UV irradiation Lamp used: High-pressure mercury lamp (USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

Comparative Example 2
(1) Base material Material: TAC (triacetyl cellulose)
Thickness: 80μm
Manufacturer: Fuji Photo Film Co., Ltd.
Product name: FT-UV-80
(2) Coating resin Material name Weight part
Resin: Pentaerythritol triacrylate 98.8
Cellulose acetate propionate 1.2
Photoinitiator: Irgacure 184 (Ciba Geigy) 3.0
Benzophenone 3.0
Particle: None
Additive: Ether-modified silicone 0.2
Diluting solvent: Toluene 125.0
Ethyl acetate 5.0
(3) Coating Coating method: Slit reverse method
Coating thickness: 8 g / m ³ (DRY)
(4) Drying Drying temperature: about 70 ° C
Drying time: about 1 min
(5) Shaped film Material: PET
Thickness: 25μm
Manufacturer: Toray Industries, Inc.
Product name: MT-HP
(6) UV irradiation Lamp used: High pressure mercury lamp (manufactured by USHIO INC.)
With conveyor
Lamp output: 160W / cm
Line speed: 10m / min
Number of irradiations: 2 pass.

  Each of the above Examples 3 to 12 was excellent in the antiglare effect and also in the image display quality.

  On the other hand, the display screen to which the antiglare film of Comparative Example 2 was applied was inferior in image display quality, particularly the screen was generally white and the contrast was low.

The table below shows the optical characteristics and surface characteristics of the above examples and comparative examples.

FIG. 1 is a schematic cross-sectional view showing the implementation of the present invention. FIG. 2 is a conceptual diagram showing light reflection and transmission with respect to the antiglare film of the present invention. FIG. 3 is a schematic cross-sectional view showing an example of manufacturing the antiglare film of the present invention. FIG. 4A is a schematic cross-sectional view showing an example of a matted film base material, and FIG. 4B is a cross-sectional view of a shaped film obtained by applying a resin to a shaped film base material. FIG. 5 is an explanatory view showing a process for producing an antiglare film, in which FIG. 5A is a cross-sectional view of a shaped film obtained by applying a resin to a shaped film substrate, and FIG. 5B is an antiglare film base. 5C is a cross-sectional view of a laminated sheet in which an ionizing radiation curable resin before curing is formed on a material, FIG. 5C is a cross-sectional view of a laminated sheet in which the shaping film of FIG. 5A is laminated on the laminated film of FIG. 5B, and FIG. Sectional view of the shaping film and the antiglare film when the lamination film is peeled off after irradiating the laminated sheet with ionizing radiation to cure the ionizing radiation curable resin layer 6A is a cross-sectional view of a shaped film coated with a resin to which fine silica particles are added, and FIG. 6B is a cross-sectional view of an antiglare film produced using the shaped film of FIG. 6A. FIG. 7 is a diagram showing an example of a coating apparatus used when coating an ionizing radiation curable resin composition. FIG. 8 is a sectional view of a polarizing plate to which the antiglare film of the present invention is applied. FIG. 9 is a sectional view of a polarizing plate to which the antiglare film of the present invention is applied. FIG. 10 is a sectional view showing a specific example of a polarizing plate to which a moisture-proof sheet is applied. FIG. 11 is a sectional view showing a specific example of a polarizing plate to which a moisture-proof sheet is applied. 12A to 12D are cross-sectional views each showing a specific example of a liquid crystal cell to which the polarizing plate of the present invention is applied.

Claims (6)

An antiglare film for a liquid crystal display polarizing plate in which an ionizing radiation curable resin layer is provided on a triacetyl cellulose film,
The ionizing radiation curable resin layer is formed by applying a coating composition comprising an ionizing radiation curable resin and silane-coupled silica particles on the triacetyl cellulose film and curing it with ionizing radiation. And
The coating composition contains 3.8 to 26.4 parts by weight of silica particles having an average particle diameter of 1 to 3 μm and subjected to silane coupling treatment with respect to 100 parts by weight of ionizing radiation curable resin. The curable resin layer has a surface roughness with a surface centerline average roughness of 0.05 to 0.6 μm, and a pitch between surface irregularities of 5 to 200 μm,
As a laminate of a triacetyl cellulose film and an ionizing radiation curable resin layer, the liquid crystal display polarizing plate has a total light transmittance of 85% or more, a haze degree of 3 to 10%, and a 60 degree glossiness of 90% or less. Dazzle film.   The antiglare film according to claim 1, wherein the surface center line average roughness is in the range of 0.05 to 0.4 µm.   The antiglare film according to claim 1, wherein the surface centerline average roughness is in the range of 0.05 to 0.25 µm.   The antiglare film according to claim 1, wherein an antireflection layer made of a metal compound is further formed on the surface of the ionizing radiation curable resin layer. The anti-glare film according to claim 4, wherein the antireflection layer comprises at least one of Al ₂ O ₃ , ZnO ₂ and MgF ₂ .   A polarizing plate comprising the antiglare film according to claim 1.

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