TWI433778B - Antiglare hard coat film and polarizing plate using the film - Google Patents

Description

Anti-glare hard coating film and polarizing plate using the same

The present invention relates to an antiglare hard coating film and a polarizing plate using the same. More specifically, the present invention relates to an anti-glare hard coating film provided with a hard coating layer containing organic fine particles, which can control an external haze value and a 60° gloss value at a desired value, and at the same time, a film An anti-glare hard coating film having a small variation in external haze value due to thickness and having excellent surface hardness which can be stably produced, and a polarizing plate using the anti-glare hard coating film.

In a display tube (CRT), a liquid crystal display (LCD), a plasma display (PDP), or the like, light is incident on the screen from the outside, and the light is reflected to blur the display screen, particularly in recent years, as the display is enlarged. Solving the above problems has become an increasingly important issue. One of the means for solving this problem is to use a member having an anti-glare hard coating layer. Then, the method for forming the antiglare hard coating layer can be roughly classified into (1) a method of physically roughening the surface when hardening the hard coating layer is formed; and (2) forming a hard coating layer. (3) A method in which a filler is mixed in a coating material; (3) three kinds of incompatible two components are mixed in a hard coating agent for forming a hard coating layer, and three methods such as phase separation are used. Each of them suppresses regular reflection of external light by forming fine irregularities on the surface, and prevents reflection of light other than fluorescent lamps. Among them, the method of mixing the filler into the hard coating agent in (2) is the mainstream. In the case of the filler, inorganic particles originally represented by cerium oxide are generally used. In addition to the whiteness of the obtained hard coating film, the reason why the ruthenium oxide particle is low can be suppressed, and the abrasion resistance which is not caused by insufficient hardening can be mentioned.

Further, an anti-glare film having an antiglare layer composed of a resin particle having a refractive index of 1.40 to 1.60 and an ionizing radiation-curable composition is formed on a transparent substrate. For example, in the case of forming an anti-glare film having an anti-glare property, an anti-glare film having an organic filler having a particle diameter equal to or larger than the film thickness of the coating film is proposed, but it is increased in order to improve the anti-glare property. In the case of large irregularities, the haze value rises, and there is a problem that the sharpness is lowered. In order to improve the amount of the organic filler added to reduce the particle size of the coating film thickness for forming the anti-glare property, the amount of the organic filler added is less than the thickness of the coating film. An organic additive with a particle size to produce a well-balanced anti-glare film.

However, in actuality, even in the above-described method, even if the balance of optical properties can be obtained, the unevenness of the particle diameter of the fine particles is used, and where there is no unevenness, comprehensive anti-glare properties are not obtained. Further, there is a problem that the external haze value due to the film thickness fluctuates greatly and the stable productivity is deteriorated. Further, in these series, the film thickness is determined by the particle size, and it is difficult to adjust the physical properties such as the surface hardness depending on the film thickness.

Patent Document 1: JP-A-6-18706

Patent Document 2: Patent No. 3515401

In the present invention, the present invention provides an anti-glare hard coating film which is an anti-glare hard coating film provided with a hard coating layer containing organic fine particles, which can control external haze value and 60° gloss. The value is a desired value, and the variation in the external haze value due to the film thickness is small, and the surface hardness which can be stably produced is excellent; and the polarizing plate using the anti-glare hard coating film is intended.

The present inventors have repeated the results of intensive studies in order to achieve the above object, and found that by using an active energy ray-sensitive composition containing an active energy ray-sensitive composition, preferably containing cerium oxide-based fine particles, This object can be achieved by the hard coating layer forming material of the organic fine particles having a specific specific gravity difference and forming a hard coating layer, and the anti-glare hard coating film having a thickness larger than the average particle diameter of the organic fine particles. The present invention has been accomplished based on the relevant discovery knowledge.

That is, the present invention provides

[1] An anti-glare hard coating film comprising a (A) active energy ray-sensitive composition and (B) a hard coating layer-forming material containing organic fine particles on a surface of a transparent plastic film. In the hard coating layer formed, the ratio of the specific gravity of the component (A) to the component (B) is 0.25 or more at a temperature of 25 ° C, and the thickness of the hard coating layer is larger than the average particle diameter of the (B) organic fine particles;

[2] The antiglare hard coating film according to [1] above, wherein the component (A) is (a) a polyfunctional (meth) acrylate monomer and/or a (meth) acrylate pre a polymer, and (b) an active energy ray-sensitive composition comprising cerium oxide-based particles;

[3] The anti-glare hard coating film according to [1] or [2] above, wherein (b) the cerium oxide-based fine particles are functional groups having a (meth)acryl fluorenyl group as surface functional groups. Oxide particles; and

[4] A polarizing plate which is bonded to a polarizing mirror by a reverse side surface of a hard coating layer forming surface of the antiglare hard coating film according to any one of the above [1] to [3] Composition.

According to the present invention, it is possible to provide an anti-glare hard coating film which is an anti-glare hard coating film provided with a hard coating layer containing organic fine particles, which can control an external haze value and a 60° gloss value as desired. The value is small, and the variation of the external haze value due to the film thickness is small; and the surface hardness which can be stably produced is excellent; and the polarizing plate using the anti-glare hard coating film.

In the antiglare hard coating film of the present invention, a hard coating layer forming material having the following composition is used for forming a hard coating layer provided on at least one side of the transparent plastic film.

[hard coating layer forming material]

The hard coating layer forming material of the present invention comprises (A) an active energy ray-sensitive composition and (B) organic fine particles.

((A) Active energy ray-sensitive composition)

In the hard coating layer forming material, as the active energy ray-sensitive composition as the component (A), it is preferred to use (a) a polyfunctional (meth) acrylate monomer and/or ( a methyl acrylate prepolymer, and (b) cerium oxide microparticles.

Further, in the present invention, the active energy ray means an ultraviolet ray or an electron ray or the like which has an energy quantum in an electromagnetic wave or a charged particle ray.

<(a) Polyfunctional (meth) acrylate monomer and/or (meth) acrylate prepolymer>

In the present invention, a polyfunctional (meth) acrylate monomer and/or a (meth) acrylate prepolymer is used as the (A) active energy ray-sensitive composition.

Examples of the polyfunctional (meth) acrylate monomer include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and neopentyl glycol. Di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxytrimethylacetic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, Ester-modified dicyclopentenyl (meth)acrylate, ethylene oxide modified di(meth)acrylate, allylic dicyclohexyl (meth)acrylate, isocyanate di(meth)acrylate Ester, trihydroxypropyl tris(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dineopentaerythritol tri(meth)acrylate, pentaerythritol three (a) Acrylate, propylene oxide modified tris (tri) propyl (meth) acrylate, tris (oxyethyl acrylate) isocyanate, propionic acid modified dine pentaerythritol penta (meth) acrylate, dioxane A polyfunctional (meth) acrylate such as tetraol hexa(meth) acrylate or caprolactone modified dipentaerythritol hexa(meth) acrylate. These monomers may be used alone or in combination of two or more.

In addition, examples of the (meth)acrylate prepolymer include a polyester acrylate type, an epoxy acrylate type, a urethane acrylate type, and a polyalcohol acrylate type. In the polyester acrylate-based prepolymer, for example, a hydroxyl group of a polyester oligo having a hydroxyl group at the terminal end obtained by condensation of a (meth)acrylic acid, an esterified polycarboxylic acid, and a polyhydric alcohol, or The hydroxyl group at the terminal of the oligomer obtained by adding an alkylene oxide to a polyvalent carboxylic acid is esterified with (meth)acrylic acid.

An epoxy acrylate-based prepolymer, for example, by reacting and esterifying (meth)acrylic acid on an oxirane ring of a lower molecular halo bisphenol type epoxy resin or a novolak type epoxy resin Get it. The urethane acrylate-based prepolymer can be obtained, for example, by a polyurethane oligomer obtained by a reaction of (meth)acrylic acid, esterification of a polyether polyol or a polyester polyol, and a polyisocyanate. Further, the polyhydric acrylate prepolymer can be obtained by esterifying a hydroxyl group of a polyether polyol with (meth)acrylic acid. These prepolymers may be used singly or in combination of two or more kinds, or may be used in combination with the above-mentioned polyfunctional (meth) acrylate monomer.

<(b) yttrium oxide microparticles>

In the present invention, colloidal cerium oxide microparticles and/or cerium oxide microparticles having surface functional groups may be used as (b) cerium oxide-based microparticles.

The colloidal cerium oxide microparticles are those having an average particle diameter of about 1 to 400 nm and having surface functional groups, and examples thereof include cerium oxide having a functional group containing a (meth)acryl fluorenyl group as a surface functional group. Fine particles (hereinafter referred to as reactive cerium oxide particles).

The above reactive cerium oxide microparticles can be, for example, polymerizable unsaturated groups having a functional group reactive with the stanol group by a stanol group on the surface of cerium oxide microparticles having an average particle diameter of about 0.005 to 1 μm. The organic compound is obtained by reaction. Examples of the polymerizable unsaturated group include a radically polymerizable (meth) acrylonitrile group.

In the case of the organic compound containing a polymerizable unsaturated group which has a functional group reactive with the above stanol group, for example, a compound represented by the formula (I) or the like is preferably used.

(wherein R ¹ is a hydrogen atom or a methyl group, and R ² is a halogen atom or

-OCH ₂ CH ₂ OH, -OH, -O(CH ₂ ) ₃ O, -Si(OCH ₃ ) ₃ functional group. )

As such compounds, for example, acrylic acid, chlorinated acrylic acid, ethyl 2-isocyanatoacrylate, glycidyl acrylate, 2,3-indolyl propyl acrylate, 2-hydroxyethyl acrylate, Acryloxypropyltrimethoxydecane, and the like, and methacrylic acid derivatives corresponding to the acrylic acid derivatives thereof. These acrylic acid derivatives or methacrylic derivatives may be used singly or in combination of two or more.

The cerium oxide microparticles bonded to the polymerizable unsaturated group-containing organic compound thus obtained are crosslinked and hardened by irradiation with an active energy ray to be an active energy ray hardening component.

The reactive cerium oxide microparticles have an effect of improving the scratch resistance of the obtained hard coating film.

An active energy ray-sensitive composition (A) containing a compound formed by bonding an organic compound having a polymerizable unsaturated group to the cerium oxide microparticles is commercially available, for example, as manufactured by JSR Co., Ltd. under the trade name "Op". Star Z7530", "Opstad Z7524", "Opstar (OPSTAR) TU4086" and so on.

In the present invention, the content of the cerium oxide-based fine particles of the component (b) is usually from about 5 to 90% by mass, preferably from 10 to 5%, based on the solid content of the active energy ray-sensitive composition of the component (A). 70% by mass.

Further, the average particle diameter of the cerium oxide particles in the cerium oxide-based fine particles of the component (b) can be measured by a laser diffraction/scattering method. In this method, the average particle diameter is determined by varying the light intensity of the diffused ‧ scattered laser light in the liquid of the dispersed particles.

((B) Organic Particles)

In the hard coating layer forming material of the present invention, examples of the organic fine particles as the component (B) include polyoxynoid fine particles, melamine resin fine particles, and acrylic resin fine particles (for example, polymethyl methacrylate). Fine particles (hereinafter referred to as PMMA-based fine particles), etc., acrylic-styrene-based copolymer fine particles, polycarbonate-based fine particles, polyethylene-based fine particles, polystyrene-based fine particles, benzoquinone Resin particles or the like. Further, the shape of the organic fine particles used in the present invention is not limited, but from the viewpoint of improving the reproducibility of the antiglare performance, it is preferable that the spherical shape can homogenize the light scattering state. From the same point of view, organic particles are particularly preferred for those having a narrow particle size distribution. The average particle diameter of the organic fine particles is preferably from 1 to 10 μm, particularly preferably from 2 to 5 μm from the viewpoint of antiglare performance, and from the same viewpoint, the particle size distribution is preferably a Coulter counter ( The particle diameter of the sharpest peak measured by the Coulter Counter method is ±50% or more, and the mass fraction of the particle diameter is 70% or more of the total.

In the present invention, the organic fine particles of the component (B) may be used singly or in combination of two or more. The blending amount is the aforementioned (A) from the viewpoint of antiglare performance. The solid content of the active energy ray-sensitive composition of the component is preferably from 0.1 to 30 parts by mass, more preferably from 1 to 20 parts by mass, per 100 parts by mass.

In the present invention, in order to increase the antiglare property by the organic fine particles of the component (B) being deposited in the vicinity of the surface of the hard coating layer, the specific gravity of the active energy ray-sensitive composition of the component (A) must be at a temperature of 25 ° C. The ratio of the organic fine particles of the component (B) is 0.25 or more. If the specific gravity difference is less than 0.25, the ratio of the organic fine particles existing in the vicinity of the surface of the hard coating layer becomes low, and desired antiglare performance cannot be obtained. The specific gravity difference is preferably 0.30 or more, more preferably 0.40 or more. Moreover, when the difference in specific gravity is too large, the amount of organic fine particles existing in the vicinity of the surface of the hard coating layer is excessively increased, and the scratch resistance of the hard coating layer may be lowered. Therefore, the specific gravity difference is preferably 1 or less, preferably 0.80 or less, more preferably 0.70 or less.

In addition, the specific gravity of the (A) active energy ray-sensitive composition at a temperature of 25 ° C is the value measured by the specific gravity measuring method of the pycnometer according to JIS Z 8804 before being hardened by irradiation with energy rays. . Further, the specific gravity of the (B) organic fine particles at a temperature of 25 ° C is a value measured by a specific gravity measuring method of a pycnometer of JIS Z 8807-1976.

(photopolymerization initiator)

In the hard coating layer forming material in the present invention, a photopolymerization initiator may be contained as desired. Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, and benzoin isobutyl group. Ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2- Hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-methylthio]phenyl]-2-iphonin-prop 1-ketone, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl)one, diphenyl ketone, p-phenyldiphenyl ketone, 4,4'-diethyl Aminodiphenyl ketone, dichlorodiphenyl ketone, 2-methyl hydrazine, 2-ethyl hydrazine, 2-tert-butyl fluorene, 2-amino hydrazine, 2-methyl-9 - Oxygen sulfur 2-ethyl-9-oxosulfur 2-chloro 9-oxosulfur 2,4-dimethyl-9-oxosulfur 2,4-diethyl-9-oxosulfur , benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylamino benzoate ester and the like.

These may be used singly or in combination of two or more kinds, and the amount thereof is selected in the range of 0.2 to 10 parts by mass based on 100 parts by mass of the total active energy ray-sensitive compound. In addition, the all-activity amount ray-curable compound is a case where the reactive cerium oxide microparticles are used as (b) cerium oxide-based microparticles, and the other is included.

(modulation of hard coating layer forming material)

In the hard coating layer forming material used in the present invention, if necessary, the active energy ray-sensitive composition of the component (A) and the organic fine particles of the component (B) are added in an appropriate ratio in an appropriate solvent. The photopolymerization initiator or various added components used as desired, such as an antioxidant, an ultraviolet absorber, a decane coupling agent, a photostabilizer, a leveling agent, an antifoaming agent, etc., can be prepared by dissolving or dispersing .

Examples of the solvent to be used herein include aliphatic hydrocarbons such as hexane and heptane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and dichloroethane; and methanol, ethanol, propanol and butyl. An alcohol such as an alcohol or a propylene glycol monomethyl ether; a ketone such as acetone, methyl ethyl ketone, 2-pentanone, isophorone or cyclohexanone; an ester of ethyl acetate or butyl acetate; Kesai Susu and other competitions, such as solvent, etc.

The concentration and viscosity of the hard coating layer forming material to be prepared are not particularly limited as long as they are coatable, and can be appropriately selected depending on the situation.

[Transparent plastic film]

In the antiglare hard coating film of the present invention, the hard coating layer forming material prepared as described above is used on at least one side of the transparent plastic film to form a hard coating layer.

The transparent plastic film described above is not particularly limited, and a substrate which is a conventional hard coating film for optical use can be suitably selected from among the recognized plastic films. Examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyethylene film, polypropylene film, cellophane, and a cellulose acetate film, a cellulose triacetate film, a cellulose acetate butyrate film, a polyvinyl chloride film, a polyvinylidene chloride film, a polyvinyl alcohol film, an ethylene-vinyl acetate copolymer film, a polystyrene film, Polycarbonate film, polymethylpentene film, polyfluorene film, polyether ether ketone film, polyether ruthenium film, polyether phthalimide film, polyimine film, fluororesin film, polyamide film, A plastic film such as an acrylic resin film, a norbornene resin film or a cycloolefin resin film.

These plastic films can be transparent or translucent, or they can be colored or uncolored, and can be selected according to the application. For example, when it is used for protection of a liquid crystal display body, it is suitable for a colorless transparent film.

The thickness of the plastic film is not particularly limited and is appropriately selected depending on the condition, but is usually in the range of 15 to 300 μm, preferably 30 to 200 μm. Further, the plastic film is intended to enhance the adhesion to the layer provided on the surface thereof, and the surface treatment can be carried out by oxidation or embossing or the like on one side or both sides as desired. Aspect of the above oxidation method, for example corona discharge treatment, plasma treatment, chromic acid treatment (wet type), flame treatment, hot air treatment, ozone-ultraviolet irradiation treatment and the ^like;. Further, aspects roughening method, for example frosted method, Solvent treatment method, etc. Although the surface treatment method is appropriately selected depending on the type of the plastic film, it is generally preferred to use a corona discharge treatment method from the viewpoints of effects and operability. Also, the bottom layer can be set.

[Formation of hard coating]

On at least one side of the transparent plastic film, using a conventionally recognized method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like The coating material is formed by coating the hard coating layer forming material, and after drying, the coating film is cured by irradiation with an active energy ray to form a hard coating layer.

Examples of the active energy ray include ultraviolet rays or electron beams. The ultraviolet light is obtained by a high pressure mercury lamp, an electrodeless lamp, a halogenated metal lamp, a xenon lamp, or the like, and the irradiation amount is usually 100 to 500 mJ/cm ² , and the electron beam is obtained by an electron beam accelerator or the like, and the irradiation amount is usually 150 to 350kV. Among the active energy rays, ultraviolet rays are particularly suitable. Further, in the case of using an electron beam, a cured film can be obtained without adding a photopolymerization initiator.

The thickness of the hard coating layer thus formed must be larger than the average particle diameter of the organic fine particles used in the present invention, so the lower limit is about 2 μm, and the hard coating film is prevented from being curled by hardening shrinkage of the hard coating layer. From the point of view, the upper limit is about 20 μm. A preferred thickness is in the range of 5 to 15 μm, and a particularly preferred thickness is 8 to 12 μm.

[Anti-glare hard coating] (optical properties)

The optical characteristics of the anti-glare hard coating of the present invention thus formed may have different values depending on the type thereof.

In the case of high contrast, the internal haze value is usually 0 to 10%. Even if the internal haze value is uneven in this range, it can be sufficiently applied depending on the type of display (design concept) because high contrast can be achieved. When the internal haze value exceeds 10%, high contrast (becoming a general-purpose type) is not obtained. Also, in the case of a general-purpose type, the internal haze value is usually 5 to 40%. If the internal haze value is less than 5%, the performance of suppressing unevenness is insufficient, and when it exceeds 40%, the visibility is lowered. A preferred internal haze value of the general-purpose antiglare hard coating film is usually from 10 to 30%, preferably from 15 to 25%.

Further, the external haze value is preferably 20% or less from the viewpoint of high contrast type, general use type, and visibility, and is preferably 5% or more from the viewpoint of antiglare property. The external haze value is a value obtained by measuring the total haze value and the internal haze value of the anti-glare hard coating film, and subtracting the difference between the internal haze values by the total haze value.

Furthermore, the 60° gloss value is preferably 20 to 120, more preferably 20 to 80. The 60° gloss value exceeds 120, the surface gloss is large (the light reflection is large), Anti-glare effects cause adverse effects. If the 60° gloss value is less than 20, it will easily fade to light brown. Further, the total light transmittance of the antiglare hard coating film is preferably 88% or more, and more preferably 90% or more. If the total light transmittance is less than 88%, the transparency may be insufficient.

The method of measuring the characteristic value of the optical light will be described later.

(effect)

The antiglare hard coating film of the present invention achieves the following effects.

(1) By specifying a difference in specific gravity between the active energy ray-sensitive composition and the organic fine particles, the organic fine particles are scattered in the vicinity of the surface of the hard coating layer to exhibit desired antiglare performance. By controlling the difference in specific gravity, the external haze value and the 60° gloss value can be controlled to a desired value.

(2) Even in a film thickness larger than the average particle diameter of the organic fine particles, the organic fine particles are present in the vicinity of the surface of the hard coating layer, thereby improving the anti-glare property and also reducing coating unevenness. Further, in comparison with the conventional anti-glare hard coating film produced by using organic fine particles having the same average particle diameter, the film thickness is inevitably increased, and the improvement in pencil hardness is expected.

(3) By using an active energy ray-sensitive composition containing cerium oxide-based fine particles, an anti-glare hard coating film having a low degree of curing shrinkage and a small curl can be obtained. Further, when an active energy ray-sensitive composition containing cerium oxide-based fine particles is used, it is possible to expand the design of the difference in specific gravity from the organic fine particles.

(other functional layers)

In the anti-glare hard coating film of the present invention, an antireflection layer such as a siloxane-based coating film or a fluorine-based coating film may be provided in the uppermost layer for the purpose of imparting antireflection properties and the like. In this case, the thickness of the antireflection layer is suitably about 0.05 to 1 μm. By providing the anti-reflection layer, reflection of a picture caused by reflection by sunlight, a fluorescent lamp, or the like is eliminated, and by suppressing the reflectance of the surface, the overall light transmittance is improved, and transparency is improved. Further, with the type of the antireflection layer, the antistatic property can be improved.

(adhesive layer)

In the antiglare hard coating film of the present invention, an adhesive layer for adhering to a liquid crystal display body or the like can be formed on the reverse surface of the plastic film and the hard coating layer. As the adhesive constituting the adhesive layer, for example, an acrylic adhesive, an amine ester adhesive, or a polyoxynoxy adhesive suitable for optical use is preferably used. The thickness of the adhesive layer is usually in the range of 5 to 100 μm, preferably 10 to 60 μm.

Further, on the adhesive layer, a release sheet may be provided as necessary. In the case of the release sheet, a release agent such as a polyoxymethylene resin is applied to various plastic films such as polyethylene terephthalate or polypropylene. The thickness of the release sheet is not particularly limited, but is usually about 20 to 150 μm.

The anti-glare hard coating film forming the adhesive layer is suitable for use as a member for imparting anti-glare properties or scratch resistance to displays such as CRTs, LCDs, and PDPs, and is particularly suitable for use in an LCD or the like. The polarizing plate is attached.

[Polarizer]

Moreover, the present invention also provides a polarizing plate comprising the above-described antiglare hard coating film of the present invention bonded to a polarizing mirror.

The liquid crystal element in the LCD has two transparent electrode substrates in which an alignment layer is generally formed, and the alignment layer is disposed inside, and the spacer is disposed to have a predetermined gap, and the periphery is sealed to sandwich the liquid crystal material in the gap. On the outer surface of the two transparent electrode substrates, a structure in which a polarizing plate is provided via an adhesive layer is provided.

Fig. 1 is a perspective view showing the configuration of an example of the above polarizing plate. As shown in the figure, the polarizing plate 10 generally has a three-layer structure in which a triethyl cellulose (TAC) film 2 and a 2' are bonded to both surfaces of a polyvinyl alcohol-based polarizer 1, and then, An adhesive layer 3 for adhering to an optical component such as a liquid crystal element is formed on the single surface, and the release sheet 4 is attached to the adhesive layer 3. Further, a surface protective film 5 is usually provided on the reverse side of the adhesive layer 3 of the polarizing plate.

The polarizing plate of the present invention is provided in the TAC films 2 and 2' provided on both sides of the polarizing mirror 1, and the above-mentioned hard coating layer according to the present invention is provided on the other TAC film. In the case where the adhesive layer 3, the release sheet 4, and the surface protective film 5 are provided on the polarizing plate, the hard coating layer according to the present invention is provided particularly on the side of the TAC film 2' on the side of the surface protective film 5.

In the method of producing the polarizing plate of the present invention, for example, the following operations can be performed. Further, Fig. 2 is a cross-sectional schematic view showing a configuration of an example of a polarizing plate of the present invention.

First, a transparent plastic film having a non-optical anisotropic film 12' such as a TAC film as a base material is used, and a hard coating layer 13 according to the present invention is formed on the other surface to form an anti-glare hard coating film 14. Then, on the single surface of the polarizing mirror 11, the TAC film 12 on which the hard coating layer 13 is not formed is laminated on the reverse side by using the adhesive layers 15, 15' to laminate the anti-glare hard coating film 14. When a TAC film is used for a transparent plastic film, other saponification treatments, such as the surface treatment described above, may be performed by laminating the adhesive with an adhesive.

Thus, the polarizing plate 20 excellent in anti-glare performance and scratch resistance is obtained. The polarizing plate 20 may be provided with the peelable surface protection film 5 shown in FIG. 1 on the surface on which the hard coating layer 13 is provided, or may be attached to the optical element of the liquid crystal element or the like on the reverse surface thereof. Adhesive layer 16 or release sheet 17 of the part.

The polarizing plate of the present invention is used for a liquid crystal element in an LCD, and can be used for light amount adjustment, a polarized interference application device, an optical defect detector, and the like.

Example

In the following, the invention is further illustrated by the examples, but the invention is not limited by the examples.

Further, the average particle diameter and specific gravity of the organic fine particles, the specific gravity of the active energy ray-sensitive composition, and the hard coating film properties were determined by the following methods.

<Organic Particles> (1) Average particle size

Determined by the Coulter Counter method.

(2) the proportion at a temperature of 25 ° C

The specific gravity of the pycnometer of JIS Z 8807-1976 was measured.

<Active energy ray-sensitive composition> (3) the proportion at a temperature of 25 ° C

The active energy ray-sensitive composition before the irradiation of the active energy ray was measured by the specific gravity of a pycnometer of JIS Z 8804.

<hard coating> (4) Overall light transmittance and total haze value

The light transmittance and total fog of the anti-glare hard coating film prepared in the examples and the comparative examples were measured in accordance with JIS K 7136 using a haze meter "NDH-2000" manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS K 7136. Degree value. Further, the total haze value indicates a total value of the internal haze value (internal haze value) and the external haze value due to the unevenness of the surface.

(5) Internal haze value and external haze value

2 parts by mass of an isocyanate crosslinking agent (manufactured by Toyo Ink Co., Ltd., trade name "BHS-8515") was added to 100 parts by mass of an acrylic adhesive (manufactured by Carbide Co., Ltd., trade name "PE-121"). And 100 parts by mass of toluene to prepare an adhesive solution. The adhesive solution was applied to a polyethylene terephthalate (manufactured by Toyobo Co., Ltd., trade name "A4300") having a thickness of 50 μm to a thickness of 20 μm after drying, and dried at 100 ° C for 3 minutes to prepare an adhesive sheet. The prepared adhesive sheet was attached to the hard coating layer of the hard coating film to prepare an internal haze determination sample. The haze value of the adhesive sheet and the internal haze determination sample was measured, and the value of the haze value of the adhesive sheet was subtracted from the haze value of the internal haze determination sample to obtain the internal haze value of the hard coating film. Further, when the internal haze values of the base film (triethylcellulose film) and polyethylene terephthalate used in the examples and the comparative examples were measured in the same manner, a value of less than 0.01% was regarded as no. The haze value was measured in the same manner as in the above (4).

(6) Evaluation of anti-glare

The hard coating film was attached to an acrylic resin blackboard [manufactured by Sumitomo Chemical Co., Ltd.] via an acrylic adhesive under a fluorescent lamp, and the anti-glare property was evaluated by the following criteria.

○: Fluorescent lamp has sufficient anti-reflection and fades to light brown

×: The anti-reflection of the fluorescent lamp is insufficient, or the anti-reflection of the fluorescent lamp is sufficient, but it is faded into a pale brown color and the visibility is poor.

(7) 60° gloss value

The gloss meter "VG2000" manufactured by Nippon Denshoku Industries Co., Ltd. was used and measured in accordance with JIS K 7105.

(8) Pencil hardness

According to JIS K 5400, the pencil scratching film hardness tester "No 553-M1" of Yasuda Seiki Co., Ltd. was used for measurement.

(9) uneven coating

The surface of the hard coating layer was visually observed, and coating unevenness was evaluated in accordance with the following criteria.

○: The coated surface was uniformly seen.

X: A portion having a high antiglare property and a low portion were mixed on the coated surface to see the entire unevenness.

(10) film thickness

The anti-glare hard coating film produced in the examples and the comparative examples, and the TAC (triethyl cellulose) film which is a transparent plastic film used for the production of the anti-glare hard coating film, respectively. The thickness was measured by a constant pressure thickness ["MH-15M" manufactured by Nikon Co., Ltd.], and the film thickness of the hard coating layer was calculated by taking the difference.

Modulation example 1 Hard coating layer coating agent 1

A hard coating agent containing (A) active energy ray-sensitive composition is uniformly mixed [JSR Corporation, trade name "Opstad Z7530": reactive cerium oxide microparticles (42% by mass), and polyfunctionality ( An active energy ray-sensitive composition composed of a methyl acrylate monomer and a (meth) acrylate prepolymer (28% by mass) (total: 70% by mass, specific gravity: 1.65), and a photopolymerization initiator ( 3 mass%) and methyl ethyl ketone (27 mass%); solid content concentration (73 mass%)] 100 parts by mass, spherical polymethyl methacrylate (PMMA)-based fine particles [Zhejiang Chemical Co., Ltd. (1) The average particle diameter of 3 μm and the specific gravity of 1.19] 3.75 parts by mass of the organic fine particles and 90 parts by mass of propylene glycol monomethyl ether are used as a diluent solvent to prepare a coating composition for a hard coating layer having a solid concentration of about 40% by mass. . The composition of the coating agent is shown in Table 1.

Modulation example 2 Hard coating layer coating agent 2

A solid content concentration of about 40% by mass was prepared in the same manner as in Preparation Example 1 except that 7.5 parts by mass of spherical fine PMMA-based fine particles (manufactured by Soken Chemical Co., Ltd., average particle diameter: 3 μm, specific gravity: 1.19) were used as (B) organic fine particles. The coating layer 2 for the hard coating layer. The composition of the coating agent is shown in Table 1.

Modulation example 3 Hard coating layer coating agent 3

A solid content concentration of about 40% by mass was prepared in the same manner as in Preparation Example 1 except that the ball-shaped PMMA-based fine particles (manufactured by Soken Chemical Co., Ltd., average particle diameter: 3 μm, specific gravity: 1.19) and 11.25 parts by mass were used as (B) organic fine particles. The coating layer 3 for the hard coating layer. The composition of the coating agent is shown in Table 1.

Modulation example 4 Hard coating layer coating agent 4

A hard coating agent containing (A) active energy ray-sensitive composition [JSR Co., Ltd., trade name "Opsta Z7530": reactive cerium oxide microparticles (42% by mass) and polyfunctionality (A) An active energy ray-sensitive composition composed of an acrylate monomer and a (meth) acrylate-based prepolymer (28% by mass) (total: 70% by mass, specific gravity: 1.65), and a photopolymerization initiator ( 3 mass%) and methyl ethyl ketone (27 mass%); solid content concentration (73 mass%)] 80 parts by mass, and hard coating containing an active energy ray-sensitive composition containing no reactive cerium oxide particles Agent [Daily Seika Chemical Co., Ltd., trade name "SELKA-BEAM EXF-L203 (CS-1)": from polyfunctional (meth) acrylate monomers and (methyl) Active energy ray-sensitive composition (65 mass%, specific gravity: 1.33) composed of an acrylate-based prepolymer, photopolymerization initiator (5 mass%), propylene glycol monomethyl acetate (30 mass%); solid Component concentration (70% by mass)] 20 parts by mass, and the specific component of the active component of the active energy ray-sensitive composition prepared by the component (A) is 1.5. 9. In the same manner as in Preparation Example 2, the coating material 4 for a hard coating layer having a solid concentration of about 40% by mass was prepared. The composition of the coating agent is shown in Table 1.

Modulation example 5 Hard coating layer coating agent 5

A hard coating agent containing the (A) active energy ray-sensitive composition [JSR Corporation, trade name "Opsta Z7530": reactive cerium oxide microparticles (42% by mass), and polyfunctionality Active energy ray-sensitive composition composed of (meth) acrylate monomer and (meth) acrylate prepolymer (28% by mass) (total: 70% by mass, specific gravity: 1.65), photopolymerization initiator (3 mass%) and methyl ethyl ketone (27 mass%); solid content concentration (73 mass%)] 10 mass parts, and hard energy containing active energy ray-sensitive composition containing no reactive cerium oxide microparticles Coating agent [manufactured by Daisei Seiki Co., Ltd., trade name "Sheikh Kabin EXF-L203 (CS-1)": polyfunctional (meth) acrylate monomer and (meth) acrylate prepolymer (65% by mass, specific gravity: 1.33), photopolymerization initiator (5 mass%), and propylene glycol monomethyl acetate (30% by mass); solid content concentration (70% by mass)] 90 parts by mass, active The specific gravity of the solid component of the energy ray-sensitive composition was adjusted to 1.36. Next, uniformly mixing spherical polystyrene-based fine particles (manufactured by Soken Chemical Co., Ltd., average particle diameter: 3.5 μm, specific gravity: 1.09), 3.75 parts by mass, as (B) organic fine particles, propylene glycol monomethyl ether, 90 parts by mass as The solvent was diluted to prepare a coating material 5 for a hard coating layer having a solid concentration of about 40% by mass. The composition of the coating agent is shown in Table 1.

Modulation example 6 Hard coating layer coating agent 6

A hard coating agent containing (A) active energy ray-sensitive composition [JSR Co., Ltd., trade name "Opsta Z7530": reactive cerium oxide microparticles (42% by mass) and polyfunctionality (A) An active energy ray-sensitive composition composed of an acrylate monomer and a (meth) acrylate-based prepolymer (28% by mass) (total: 70% by mass, specific gravity: 1.65), and a photopolymerization initiator ( 3 mass%) and methyl ethyl ketone (27 mass%); solid content concentration (73 mass%)] 30 parts by mass, and hard coating containing active energy ray-sensitive composition containing no reactive cerium oxide particles Agent [Dai Ri Jinghua Industrial Co., Ltd., trade name "Sheikh Kabin EXF-L203 (CS-1)": polyfunctional (meth) acrylate monomer and (meth) acrylate prepolymer (65 mass%, specific gravity 1.33), photopolymerization initiator (5 mass%), and propylene glycol monomethyl acetate (30 mass%); solid content concentration (70 mass%)] 70 mass parts, preparation (A The specific gravity of the component as a solid component of the composition was 1.43. In the same manner as in Preparation Example 2, the coating material 6 for a hard coating layer having a solid concentration of about 40% by mass was prepared. The composition of the coating agent is shown in Table 1.

Modulation example 7 Hard coating layer coating agent 7

In addition to the use of a hard coating agent containing an active energy ray-sensitive composition containing no (A) reactive cerium oxide particles [manufactured by Dairi Seiki Co., Ltd., trade name "Sheikh Kabin EXF-L203 (CS-1)" : a polyfunctional (meth) acrylate monomer and a (meth) acrylate prepolymer (65 mass %, specific gravity 1.33), a photopolymerization initiator (5 mass %), and propylene glycol monomethyl B In the same manner as in Preparation Example 1, the coating material 7 for a hard coating layer having a solid concentration of about 40% by mass was prepared in the same manner as in Preparation Example 1 except that the acid ester (30% by mass) and the solid content (70% by mass) were used. The composition of the coating agent is shown in Table 1.

Example 1

On the surface of a TAC (triethyl fluorene cellulose) film (manufactured by Fujifilm Co., Ltd.) having a thickness of 80 μm, the coating material 1 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm. After drying in an oven at 70 ° C for 1 minute, ultraviolet rays of 300 mJ/cm ² were irradiated with a high pressure mercury lamp to prepare an antiglare hard coating film.

The properties of the hard coating film are shown in Table 2.

Example 2

The same procedure as in Example 1 was carried out to prepare an antiglare hard coating film, except that the coating material 1 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 9 μm.

The properties of the hard coating film are shown in Table 2.

Example 3

An anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 2 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

Example 4

The same procedure as in Example 1 was carried out to prepare an antiglare hard coating film, except that the coating material 3 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

Example 5

An anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 4 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

Example 6

An anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 5 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

Comparative example 1

An anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 6 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

Comparative example 2

The anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 7 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 2.5 μm.

The properties of the hard coating film are shown in Table 2.

Comparative example 3

An anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 7 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 3 μm.

The properties of the hard coating film are shown in Table 2.

Comparative example 4

The anti-glare hard coating film was produced in the same manner as in Example 1 except that the coating material 7 obtained by the preparation of the Meyer strip was prepared to have a cured film thickness of about 10 μm.

The properties of the hard coating film are shown in Table 2.

[Remarks]

1) The content ratio of the reactive cerium oxide microparticles in the active energy ray-sensitive composition (solid component) of the component (A) is shown.

2) The ratio of the amount of the organic fine particles added as the component (B) to the active energy ray-sensitive composition (solid component) which is the component (A) is shown.

In any of Examples 1 to 6, the difference in specific gravity between the component (A) and the component (B) was more than 0.25, and any of the antiglare property, the pencil hardness, and the coating unevenness were good.

In any of Comparative Examples 1 to 4, the difference in specific gravity between the component (A) and the component (B) was less than 0.25, and any one of the antiglare property, the pencil hardness, and the coating unevenness was insufficient.

The anti-glare hard coating film of the present invention is provided with an anti-glare hard coating film comprising a hard coating layer of organic fine particles, and is suitable for controlling an external haze value and a 60° gloss value at a desired value, and The external haze value due to the film thickness is small and stable, and it is suitable for components such as CRT, LCD, PDP, etc., which are imparted with anti-glare properties or scratch resistance, and are particularly suitable as polarized light in LCDs and the like. For board use.

1. . . Polyvinyl alcohol polarizer

2. . . TAC film

2'. . . TAC film

3. . . Adhesive layer

4. . . Peeling piece

5. . . Surface protection film

10. . . Polarizer

11. . . Polarizer

12. . . TAC film

12’. . . TAC film

13. . . Hard coating

14. . . Anti-glare hard coating

15. . . Subsequent layer

15’. . . Subsequent layer

16. . . Adhesive layer

17. . . Peeling piece

20. . . Polarizer

Fig. 1 is a perspective view showing the constitution of an example of a polarizing plate.

Fig. 2 is a cross-sectional schematic view showing the configuration of an example of a polarizing plate of the present invention.

11. . . Polarizer

12. . . TAC film

12’. . . TAC film

13. . . Hard coating

14. . . Anti-glare hard coating

15. . . Subsequent layer

15’. . . Subsequent layer

16. . . Adhesive layer

17. . . Peeling piece

20. . . Polarizer

Claims (4)

An anti-glare hard coating film characterized in that it has a hardness formed on a surface of a transparent plastic film using a hard coating layer-forming material containing (A) an active energy ray-sensitive composition and (B) organic fine particles. In the coating layer, the ratio of the specific gravity of the component (A) to the component (B) is 0.25 or more at a temperature of 25 ° C, and the thickness of the hard coating layer is larger than the average particle diameter of the (B) organic fine particles. An anti-glare hard coating film according to claim 1, wherein the component (A) comprises (a) a polyfunctional (meth)acrylate monomer and/or a (meth)acrylate prepolymer. And an active energy ray-sensitive composition of (b) cerium oxide-based fine particles. An anti-glare hard coating film according to claim 1 or 2, wherein the (b) cerium oxide-based fine particles are cerium oxide fine particles having a functional group containing a (meth)acryl fluorenyl group as a surface functional group. A polarizing plate comprising a reverse side surface of a hard coating layer forming surface of the antiglare hard coating film according to any one of claims 1 to 3, which is bonded to a polarizing mirror.