JP2009198811A - Polarizing plate protecting film and polarizing plate using the same and image display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate protecting film having excellent pencil hardness, prevented from discoloration with the change of temperature and humidity and having excellent durability, the polarizing plate using the same and an image display. <P>SOLUTION: The polarizing plate protecting film includes a hard coat layer at least on one surface of a film substrate and the thickness of the hard coat layer is ≥10 μm and ≤40 μm, the moisture permeability of the film provided with the hard coat layer is ≥700 g/m<SP>2</SP>/day and ≤2,500 g/m<SP>2</SP>/day under a condition of 65°C and 95% RH. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polarizing plate protective film, a polarizing plate using the same, and an image display device.

In the polarizing plate, a polarizing plate protective film (hereinafter sometimes referred to as a protective layer) is bonded to both surfaces or one surface of a polarizing film having polarizing ability through an adhesive layer.
As a polarizer material, polyvinyl alcohol (hereinafter sometimes referred to as PVA) is mainly used. After the PVA film is uniaxially stretched, it is dyed with iodine or a dichroic dye or dyed. The polarizing film is formed by stretching and further crosslinking with a boron compound.
As the protective layer, cellulose triacetate (hereinafter sometimes referred to as TAC) is mainly used because it is optically transparent and has low birefringence and a smooth surface.

  However, when TAC is used as a protective layer, TAC permeates moisture to some extent, so the polarization characteristics of the polarizer may deteriorate due to changes in temperature and humidity during long-term use, and light leakage may occur. It is rare.

Moreover, the conventional polarizing plate protective film has a surface easily damaged, and a hard coat layer is laminated on at least one surface of the surface for the purpose of imparting scratch resistance. Usually, the hard coat layer is formed as a thin coating film of about 3 to 15 μm with a thermosetting resin or an ionizing radiation curable resin such as an ultraviolet curable resin directly on the protective film or through a primer layer of about 1 μm. If the thickness is simply increased, the hardness of the obtained hard coat film is improved. In addition, it is known that the moisture permeability of the polarizing plate protective film is reduced by providing an ionizing radiation curable resin such as an ultraviolet curable resin (see Patent Document 1), which is preferable from the viewpoint of polarizing plate durability.
However, a film with low moisture permeability has a problem that it is difficult to dry in the polarizing plate manufacturing process.

  On the other hand, it has been reported that a film made of a norbornene-based resin is useful as a phase plate with small fluctuations in optical characteristics even when temperature, humidity, and the like change (see Patent Document 2). However, a film made of a norbornene-based resin has preferable characteristics that it hardly permeates moisture and hardly changes humidity, but there is a problem that it is difficult to dry in the polarizing plate manufacturing process.

In particular, when a polarizing plate is produced using a film made of norbornene-based resin and a TAC film having a thick hard coat layer, the moisture permeability of both films is low, and drying in the polarizing plate production process becomes insufficient. In some cases, the polarizing plate may be colored due to the change of.
JP 2006-332042 A JP-A-5-2108

  An object of the present invention is to provide a polarizing plate protective film excellent in pencil hardness, preventing discoloration of a polarizing plate due to changes in temperature and humidity, and having excellent durability, and a polarizing plate and an image display device using the same. is there.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by the following means, and have completed the present invention.

1. A polarizing plate protective film having a hard coat layer on at least one surface on a film substrate, wherein the hard coat layer has a thickness of 10 μm or more and 40 μm or less, and moisture permeability of the film provided with the hard coat layer but under conditions of ^{RH 65 ℃ 95%, 700g /} m 2 / day or more, the polarizer protective film is less than 2500g ^/ m 2 ^/ day.
2. 2. The polarizing plate protective film according to 1 above, wherein the hard coat layer contains porous particles.
3. 3. The polarizing plate protective film according to 1 or 2, wherein the porous particles are acrylic resin particles containing polymethyl methacrylate or methyl methacrylate as a copolymerization component.
4). The polarizing plate protective film according to 1 or 2, wherein the porous particles are polyamide porous particles.
5. The polarizing plate protective film according to any one of 1 to 4, wherein a mass average particle diameter of the porous particles is in a range of 30 to 120% with respect to a thickness of the hard coat layer.
6). The polarizing plate protective film according to any one of 1 to 5, wherein the porous particles are contained in an amount of 5 to 10 parts by mass with respect to 100 parts by mass of the resin forming the hard coat layer.
7). The polarizing plate protective film according to any one of 1 to 6, wherein the film substrate is cellulose acylate.
8). The polarizing plate protective film according to any one of 1 to 7 above, wherein the film base has a thickness of 20 μm to 70 μm.
9. The polarized light according to any one of 1 to 8, wherein the hard coat layer contains translucent particles, and an average particle diameter of the translucent particles is in a range of 30 to 75% of a thickness of the hard coat layer. Board protection film.
10. The polarizing plate protection according to any one of 1 to 9, wherein the hard coat layer is formed using a composition for forming a hard coat layer containing the following component (A), component (B) and component (C): the film.
(A) Component: at least one selected from urethane acrylate and urethane methacrylate (B) Component: at least one selected from polyol acrylate and polyol methacrylate (C) Component: selected from (C1) and (C2) below A polymer or copolymer formed from at least one of the above or a mixed polymer of the polymer and the copolymer (C1): an alkyl acrylate having an alkyl group having at least one of a hydroxyl group and an acryloyl group (C2): a hydroxyl group and an acryloyl 10. alkyl methacrylate having an alkyl group having at least one of the groups; Furthermore, the polarizing plate protective film in any one of said 1-10 in which the antireflection layer is formed on the said hard-coat layer.
12 It is a polarizing plate containing a polarizer, Comprising: Furthermore, the polarizing plate containing the polarizing plate protective film in any one of said 1-11.
13. It is a polarizing plate containing a polarizer, Comprising: One polarizing film of this polarizing plate is a norbornene-type resin film, and the other polarizing plate is a polarizing plate protective film in any one of said 1-11.
14 The image display apparatus which has a polarizing plate protective film in any one of said 1-11, or the polarizing plate of said 12 or 13.

  According to the present invention, it is possible to provide a polarizing plate protective film excellent in pencil hardness, preventing discoloration of the polarizing plate due to changes in temperature and humidity, and having excellent durability, and a polarizing plate and an image display device using the same.

  Hereinafter, the present invention will be described in more detail. In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. . In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acrylic acid” and the like.

<Layer structure of polarizing plate protective film>
The polarizing plate protective film of the present invention is a polarizing plate protective film having a hard coat layer on at least one surface on a film substrate, wherein the hard coat layer has a thickness of 10 μm or more and 40 μm or less, moisture permeability of the film having a coating layer is, under the conditions of ^{RH 65 ℃ 95%, 700g /} m 2 / day or more, a polarizing plate protective film is not more than 2500g ^/ m 2 ^/ day. The moisture permeability of the film is more preferably 1000 g / m ² / day or more and 2000 g / m ² / day or less.

  The polarizing plate protective film of the present invention has a hard coat layer on at least one surface on the film substrate. The hard coat layer may be an antiglare hard coat layer in which translucent particles are dispersed in the matrix of the layer. The hard coat layer may be a single layer or a plurality of layers, for example, 2 to 4 layers.

The binder resin for forming a matrix of the hard coat layer of the present invention preferably contains the following components (A), (B) and (C).
(A) Component: at least one selected from urethane acrylate and urethane methacrylate (B) Component: at least one selected from polyol acrylate and polyol methacrylate (C) Component: selected from (C1) and (C2) below A polymer or copolymer formed from at least one of the above or a mixed polymer of the polymer and the copolymer (C1): an alkyl acrylate having an alkyl group having at least one of a hydroxyl group and an acryloyl group (C2): a hydroxyl group and an acryloyl Alkyl methacrylate having an alkyl group having at least one of the groups

The example of the preferable layer structure of the polarizing plate protective film of this invention is shown below. In the following configuration, the base film refers to a support composed of a film.
・ Base film / Anti-glare hard coat layer ・ Base film / Antistatic layer / Anti-glare hard coat layer ・ Base film / Anti-glare hard coat layer / Low refractive index layer ・ Base film / Anti-glare Hard coat layer / antistatic layer / low refractive index layer • Base film / hard coat layer / antiglare layer / low refractive index layer • Base film / hard coat layer / antiglare layer / antistatic layer / low refractive index layer -Base film / hard coat layer / antistatic layer / anti-glare layer / low refractive index layer- Base film / anti-glare hard coat layer / high refractive index layer / low refractive index layer-Base film / anti-glare property Hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Antistatic layer / Base film / Anti-glare hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Material film / antistatic layer / antiglare hard coat layer / medium refractive index layer / high refractive index layer / low bending Folding layer ・ Antistatic layer / Base film / Anti-glare hard coat layer / High refractive index layer / Low refractive index layer / High refractive index layer / Low refractive index layer

  In the polarizing plate protective film of the present invention, layers other than the hard coat layer may be coated. Examples of these layers include an antiglare layer, an antistatic layer, a low refractive index layer, and an antifouling layer as described above. Layer and the like. More preferably, the hard coat layer has functions such as an antiglare layer, an antistatic layer and an antifouling layer at the same time.

In the present invention, it is preferable to have an antireflection film including a medium refractive index layer / high refractive index layer / low refractive index layer from the viewpoint of low reflection. For example, JP-A-8-122504 and 8 -110401 gazette, 10-300902 gazette, Unexamined-Japanese-Patent No. 2002-243906, Unexamined-Japanese-Patent No. 2000-11706, etc. are mentioned. From the viewpoint of simple production and high productivity, preferred embodiments of the present invention include a polarizing plate protective film having a single hard coat layer on the support, and a single hard coat layer and a single layer on the support. It is a polarizing plate protective film having a single low refractive index layer in this order.
Film having a hard coat layer of the present invention, under the conditions of ^{RH 65 ℃ 95%, 700g /} m 2 / day or more, or less 2500g ^/ m 2 ^/ day, to achieve this condition, the hard coat It is used to include porous particles in the layer. This will be described in detail below.

<Moisture permeability>
The measurement method of moisture permeability is "Polymer Physical Properties II" (Polymer Experiment Course 4, Kyoritsu Shuppan), pages 285-294: Measurement of vapor permeation (mass method, thermometer method, vapor pressure method, adsorption amount method) The film sample of 70 mmφ according to the present invention was conditioned at 60 ° C. and 95% RH for 24 hours, respectively, and from the mass difference before and after the humidity adjustment, according to JIS Z-0208, per unit area Was calculated (g / m ² ).
At this time, the operation of taking out and weighing the cup placed in the thermo-hygrostat at an appropriate time interval is repeated, and the mass increase per unit time is obtained for each of two consecutive weighings, and it is constant within 5%. Evaluation continued until. Moreover, in order to exclude the influence by the moisture absorption etc. of a sample, the blank cup which does not put a hygroscopic agent was measured, and the value of moisture permeability was correct | amended.
In the present invention, when measuring moisture permeability, the sample is placed on the cup so that the hard coat layer is on the cup side of the base film, and the base film is on the side opposite to the hard coat layer. The moisture permeability was measured.

<Configuration of hard coat layer>
The thickness of the hard coat layer is 10 μm to 40 μm, more preferably 15 μm to 25 μm. When the thickness is less than 10 μm, the pencil hardness decreases. When the pencil hardness exceeds 40 μm, even when containing porous particles, the moisture permeability is 700 ° C./m ² / day or more and 2500 g / day under the condition of 65 ° C. and 95% RH. Discoloration of the polarizing plate occurs without being less than m ² / day. Also, when the moisture permeability is 65 ° C. and 95% RH, and less than 700 g / m ² / day, the drying in the polarizing plate manufacturing process is not preferable, and when it exceeds 2500 g / m ² / day. The polarizing plate durability deteriorates.

  The hard coat layer of the present invention is formed by applying, drying and curing a coating liquid (also referred to as a hard coat layer forming composition) containing porous particles, matrix-forming components (such as binder monomers) and an organic solvent. can do.

  The coating liquid for forming the hard coat layer is, for example, binder monomers that are cured by ionizing radiation, translucent particles, a polymerization initiator, preferably a polymer compound for adjusting the viscosity of the coating liquid, curl reduction And inorganic fillers for adjusting the refractive index, coating aids and the like.

The hard coat layer preferably contains porous particles, and the mass average particle diameter of the porous particles is in the range of 30 to 120% of the thickness of the hard coat layer. If it is less than 30%, the effect of adding porous particles decreases, and if it exceeds 120%, the variation in moisture permeability increases due to the variation in film thickness, making it difficult to control moisture permeability. The porous particles are not particularly limited, but acrylic resin particles or polyamide porous particles containing methyl methacrylate as a copolymerization component are preferable from the viewpoint of particle shape, refractive index and the like.
The particle size distribution of the particles is measured by a Coulter counter method, and the measured distribution is converted into a particle mass (volume) distribution. The mass average particle diameter is calculated from the obtained particle distribution.

The acrylic resin particles containing methyl methacrylate of the present invention as a copolymerization component will be described.
The acrylic resin particles can be produced, for example, by preparing seed particles as described below, swelling them, and subjecting the seed particles to a polymerization reaction.
The acrylic resin particle seed particle (which may be simply referred to as “seed particle”), which is the porous particle of the present invention, is 70% by mass (hereinafter simply referred to as “%”) using polymethyl methacrylate or methyl methacrylate as a copolymerization component. ], Preferably 80% or more, more preferably 90% or more acrylic resin particles. The seed particles can be produced by a conventional method. For example, basic particles having a small particle diameter such as polymethyl methacrylate can be obtained by swelling with a swelling monomer such as methyl methacrylate and then polymerizing. . This swelling / polymerization may be performed a plurality of times. In addition to producing the seed particles by the above method, the seed particles can also be produced directly by a polymerization method such as an emulsion polymerization method, a soap-free polymerization method, or a dispersion polymerization method. In addition to the above-mentioned methyl methacrylate, the swelling monomer used in producing the seed particles includes methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and isopropyl (meth) acrylate as copolymerization components. Butyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, etc. It may contain (meth) acrylic acid alkyl ester, styrene and the like. If the seed particles contain 30% or more of (meth) acrylic acid alkyl ester and 5% or more of styrene, porous monodisperse particles may not be obtained.

  The seed particles are preferably spherical. The average particle diameter of the seed particles is preferably 0.5 μm to 4.5 μm, and particularly preferably 1.3 μm to 3.5 μm. The average molecular weight of the seed particles is not particularly limited, but is preferably 150,000 to 300,000, particularly preferably 180,000 to 270,000. If this average molecular weight is less than 150,000, it may be difficult to become porous, and if it is more than 300,000, the pores may be biased to a distorted particle. The average molecular weight is a standard polystyrene equivalent mass average molecular weight measured by a gel permeation chromatography method (GPC method).

  The seed particles can be swollen with a swelling liquid containing a monomer mixture containing 70% by mass or more of polymethyl methacrylate or methyl methacrylate and 3-8% by mass of divinylbenzene and an oil-soluble polymerization initiator.

  The monomer mixture contained in the swelling liquid contains 70% or more of methyl methacrylate, preferably 80% or more, and more preferably 90% or more. The monomer mixture contains 3 to 8%, preferably 3 to 6% of divinylbenzene. This divinylbenzene acts as a cross-linking agent, and if it is less than 3%, it may not be porous, and if it is more than 8%, the opening of porous pores may be concentrated in one pole. .

  As in the case of seed particles, the monomer mixture includes methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and (meth) acrylic in addition to the methyl methacrylate. (Meth) acrylic acid such as butyl acid, isobutyl (meth) acrylate, tertiary butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate Monomers such as alkyl esters and styrene may be included. The (meth) acrylic acid alkyl ester monomer is 27% or less, preferably 17% or less, more preferably 7% or less in the monomer mixture. If these monomers exceed 27%, it may not be porous, which is not preferable. If the styrene monomer is contained in an amount of 5% or more, porous monodisperse particles may not be obtained, which is not preferable.

  Examples of the oil-soluble polymerization initiator contained in the swelling liquid include peroxide polymerization initiators such as benzoyl peroxide, lauroyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, and azobis. An azo polymerization initiator such as isobutyronitrile can be used. The oil-soluble polymerization initiator is preferably about 0.2 to 4 parts by mass, particularly preferably about 1 to 2 parts by mass with respect to 100 parts by mass of the monomer mixture.

  In order to swell the seed particles with this swelling liquid, it is preferable to provide a swelling time of a certain time at a certain temperature, and a suitable range is 0.5 to 3 hours at room temperature to 50 ° C. It is preferable that the seed particles are swollen about 20 to 80 times in mass ratio with this swelling liquid.

  Moreover, it is preferable to add water and an emulsifier to the swelling liquid and pre-emulsify with a homogenizer or the like. Further, a polymerization inhibitor or the like may be added to these swelling liquids.

  The seed particles swollen with the swelling liquid as described above are then subjected to a polymerization reaction. This polymerization reaction can be performed by a conventional method.

  In the polymerization, polyvinyl alcohol, polyoxyethylene polycyclic phenyl ether sulfate, hydroxypropyl cellulose, or the like may be added as a dispersion stabilizer.

  Further, after the polymerization, purification such as washing, filtration or the like may be performed with an aqueous solution of alcohol such as methyl alcohol, ethyl alcohol, isopropyl alcohol or the like.

  The acrylic resin particles of the present invention thus obtained have a substantially spherical shape and are porous having pores that lead not only to the surface but also to the inside. The acrylic resin particles have a narrow particle size distribution and are monodispersed.

  The average particle diameter of the acrylic resin particles is about 2 to 20 μm, preferably about 5 to 15 μm. Further, the CV value indicating the dispersibility (variation) of the particle size is usually less than 15%, preferably less than 10%.

  Next, the polyamide porous particles will be described. Examples of the polyamide constituting the porous particles include various known ones. For example, it can be obtained by ring-opening polymerization of a cyclic amide or polycondensation of a dicarboxylic acid and a diamine. As monomers, polycondensation of amino acids such as crystalline polyamide obtained by ring-opening polymerization of cyclic amides such as ε-caprolactam and ω-laurolactam, ε-aminocaproic acid, ω-aminododecanoic acid, ω-aminoundecanoic acid, etc. Or dicarboxylic acids and derivatives such as succinic acid, adipic acid, sebacic acid, terephthalic acid, isophthalic acid, 1,4-cyclohexyldicarboxylic acid, and ethylenediamine, hexamethylenediamine, 1,4-cyclohexyldiamine, m-xylylenediamine, penta Those obtained by polycondensation of diamines such as methylenediamine and decamethylenediamine.

  The polyamide is a polyamide composed of a homopolymer and a copolymer thereof, or a derivative thereof. Specifically, polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 66 / 6T (T represents a terephthalic acid component), and the like. Moreover, the mixture of the said polyamide may be sufficient. Particularly preferred are polyamide 6 and polyamide 66.

  The molecular weight of the polyamide is 2,000-100,000. Preferably it is 5,000-40,000.

  The polyamide porous particle of the present invention is a simple substance or a mixture of a spherical shape, a substantially spherical shape, a sloping ball (C-type) shape, or a dumbbell shape. % Or more is preferably a uniform particle composed of one kind of particle shape. If the amount is less than 70% by mass, the fluidity as a powder material may be unfavorable.

  The polyamide porous particles of the present invention preferably have a mass average particle diameter of 1 to 30 μm. When the mass average particle diameter is smaller than 1 μm, the handling operation is deteriorated, and the wavelength dependence may be increased depending on the degree of light scattering. On the other hand, if the mass average particle diameter is larger than 30 μm, the unevenness of the scattered light is too conspicuous, which is not preferable.

The specific surface area of the polyamide porous particles of the present invention is preferably 0.1 to 80 m ² / g. The average pore diameter of the polyamide porous particles of the present invention is preferably 0.01 to 0.8 μm.

  The polyamide porous particles of the present invention are prepared by mixing a solution (A) mainly composed of polyamide and a good solvent for polyamide and a specific non-solvent (B) in the polyamide to form a uniform solution, and then depositing Manufactured.

  As a good solvent for polyamide in the present invention, a phenol compound or formic acid is preferred. Specifically, phenol, o-cresol, m-cresol, p-cresol, cresolic acid, chlorophenol and the like are preferable as the phenol compound. These are preferable because the crystalline polyamide is dissolved or accelerated by heating at room temperature or at a temperature of 30 to 90 ° C. Particularly preferred is phenol. Phenol is less toxic than other solvents and is safe for work. Further, it is convenient because it can be easily distilled off from the obtained porous fine particles.

  A freezing point depressant may be added to the polyamide solution (A). As the freezing point depressant, a non-solvent of polyamide can be used as long as the polyamide in the polyamide solution is not precipitated. Examples of freezing point depressants include water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, Mention may be made of 1-hexanol, ethylene glycol, triethylene glycol, propylene glycol, glycerol and diglycerol.

  The polyamide concentration in the solution (A) is preferably in the range of 0.1 to 30% by mass, more preferably in the range of 0.2 to 25% by mass. If the proportion of polyamide in the polyamide solution exceeds 30% by mass, it may be difficult to dissolve or a uniform solution may not be obtained. Moreover, even if it melt | dissolves, since the viscosity of a solution becomes high and becomes difficult to handle, it is not preferable. When the polyamide ratio is lower than 0.1% by mass, the polymer concentration may be low and the product productivity may be low.

  The non-solvent (B) of the polyamide of the present invention is preferably one that is at least partially compatible with the good solvent of the solution (A). Examples of the non-solvent (B) include compounds selected from the group consisting of water and polyamide-insoluble organic solvents. The non-solvent (B) may be a mixture of two or more solvents. The non-solvent (B) is preferably one that does not dissolve 0.01% by mass or more of the polyamide in the polyamide solution at a liquid temperature of 25 ° C.

  Examples of polyamide insoluble organic solvents include alkylene glycols such as ethylene glycol and propylene glycol.

  Other examples of polyamide insoluble organic solvents include monohydric and trihydric alcohols. The monohydric alcohol is preferably a monohydric alcohol having 1 to 6 carbon atoms. It may be linear or branched. Examples of monohydric alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, 1- Mention may be made of hexanol, ethylene glycol, triethylene glycol, propylene glycol. Examples of the trihydric alcohol include glycerin. Moreover, acetone can be mentioned as a ketone.

  When the polyamide is polyamide 6, the non-solvent (B) is preferably a mixture containing water and a polyamide-insoluble solvent (preferably a monohydric alcohol). When the polyamide is polyamide 12, it is a mixture containing alkylene glycol and a polyamide-insoluble organic solvent (preferably a trihydric alcohol) other than alkylene glycol in the non-solvent (B).

  In order to prepare polyamide porous particles, a method of mixing the solution (A) and the non-solvent (B) to form a uniform mixed solution temporarily and then allowing to stand, can be used. Porous particles are deposited. The liquid temperature of the mixed solution for precipitating the polyamide porous particles is preferably in the range of 0 ° C to 80 ° C, particularly preferably in the range of 20 ° C to 40 ° C.

  A thickener may be added to the mixed solution of the solution (A) and the non-solvent (B) for the purpose of preventing aggregation of the precipitated polyamide particles to increase the viscosity of the mixed solution. Examples of the thickener include polyalkylene glycols having a mass average molecular weight of 1000 or more (particularly in the range of 1100 to 5000). Examples of polyalkylene glycols include polyethylene glycol and polypropylene glycol. As a method of adding a thickener, either a method of adding a thickener simultaneously with mixing the solution (A) and the non-solvent (B), or a method of adding a thickener to a mixed solution immediately after adjustment. This method may be used. Two or more polyalkylene glycols can be used in combination.

  The order of adding the solution (A) and the non-solvent (B) is not particularly limited as long as the uniformity of the solution is maintained.

  In the present invention, the prepared polyamide porous particles can be solid-liquid separated by a method such as decantation, filtration or centrifugation.

  In the present invention, the prepared polyamide porous particles are obtained by bringing the polyamide non-solvent compatible with the good solvent of the solution (A) at a temperature of 40 ° C. or higher at a temperature of 40 ° C. or higher. The good solvent can be extracted and removed from the polyamide porous particles.

  Compound selected from the group consisting of aliphatic alcohols, aliphatic or aromatic ketones, aliphatic or aromatic hydrocarbons, and water as examples of polyamide non-solvents used to extract and remove good solvents from solution (A) Can be mentioned. The non-solvent may be a mixture of two or more types, and preferably has a liquid temperature of 40 ° C. and does not dissolve 0.01% by mass or more of polyamide.

  Examples of the aliphatic alcohol include monovalent aliphatic alcohols having 1 to 3 carbon atoms such as methanol, ethanol, 1-propanol, and 2-propanol.

  Examples of the aliphatic ketone include acetone and methyl ethyl ketone. Examples of aromatic ketones include acetophenone, propiophenone, and butyrophenone.

  Examples of aromatic hydrocarbons include toluene and xylene. Examples of aliphatic hydrocarbons include heptane, hexane, octane, and n-decane.

  The particle size distribution of the porous particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution. The mass average particle diameter is calculated from the obtained particle distribution.

  The porous particles are preferably added at a ratio of 2 to 30 parts by mass for achieving a preferable range of moisture permeability per 100 parts by mass of the resin forming the hard coat layer. 2-10 mass parts is further more preferable, and 5-10 mass parts is especially preferable.

<Translucent particles of hard coat layer>
In the present invention, the hard coat layer may contain translucent particles, and resin particles and / or inorganic fine particles are used as the translucent particles.

  Specific examples of the resin particles include, for example, crosslinked polymethyl methacrylate particles, crosslinked methyl methacrylate-styrene copolymer particles, crosslinked polystyrene particles, crosslinked methyl methacrylate-methyl acrylate copolymer particles, crosslinked acrylate-styrene copolymer particles, Preferred examples include resin particles such as melamine / formaldehyde resin particles and benzoguanamine / formaldehyde resin particles. Of these, crosslinked styrene particles, crosslinked polymethyl methacrylate particles, crosslinked methyl methacrylate-styrene copolymer particles, and the like are preferable. Furthermore, the surface of these resin particles is a so-called surface-modified particle in which a compound containing a fluorine atom, a silicon atom, a carboxyl group, a hydroxyl group, an amino group, an sulfonic acid group, a phosphoric acid group or the like is chemically bonded, or a nano particle such as silica or zirconia. The particle | grains which couple | bonded the inorganic fine particle of the size to the surface are also mentioned preferably. Moreover, inorganic fine particles can also be used as the translucent particles. Specific examples of the inorganic fine particles include silica particles and alumina particles, and silica particles are particularly preferably used.

  In the present invention, in the case where the unevenness of coating and the unevenness of interference are inconspicuous, or from the viewpoint of cost, the refractive index of the matrix is 1.54 or less, and particularly preferably the refractive index is 1.53 or less. The particles are preferably crosslinked polymethylmethacrylate particles, crosslinked methylmethacrylate-styrene copolymer particles, and silica particles. When using crosslinked methyl methacrylate-styrene copolymer particles, the copolymerization ratio of styrene is preferably 50% or more and 90% or less.

As the shape of the particle, either a true sphere or an irregular shape can be used. The particle size distribution is preferably monodisperse particles because of the haze value, controllability of diffusibility, and uniformity of the coated surface. For example, when particles having a particle size of 20% or more than the average particle size are defined as coarse particles, the proportion of coarse particles is preferably 1% or less, more preferably 0.1% or less of the total number of particles. Yes, more preferably
0.01% or less. Particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and particles having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

  The particle size distribution of the particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution. The average particle size is calculated from the obtained particle distribution.

In the polarizing plate protective film of the present invention, the haze value resulting from surface scattering is preferably 0 to 10%, and more preferably 0.5 to 5%. By making the surface haze in this range, a polarizing plate protective film excellent in black tightening can be obtained. The haze value resulting from internal scattering is preferably 8 to 90%, more preferably 10 to 40%, and most preferably 10 to 30%. By setting the internal haze in this range, it is possible to practically satisfy the two performances of lowering the surface contrast and preventing glare. These hazes can be adjusted by adjusting the type and amount of the light-transmitting particles.
The average particle diameter of the translucent particles contained in the hard coat layer is in the range of 30 to 75% of the thickness of the hard coat layer, and preferably in the range of 30 to 50%. When the average particle diameter of the translucent particles is 30% or more, a sufficient uneven shape can be formed on the surface of the antiglare hard coat layer, and a sufficient antiglare function can be imparted. On the other hand, if the average particle diameter of the translucent particles is 75% or less, the unevenness of the surface can be made an appropriate size, the appearance can be improved, and the reflected light can be scattered appropriately. And white blurring can be prevented. Moreover, in this invention, the average particle diameter of the said translucent particle is 4.0-25.0 micrometers, for example, Preferably, it is 5.0-20.0 micrometers, More preferably, it is the range of 6-15.0 micrometers. is there.

<Matrix forming resin for hard coat layer>
The matrix-forming resin (binder polymer) for forming the matrix for forming the hard coat layer is not particularly limited, but is a translucent polymer having a saturated hydrocarbon chain or a polyether chain as the main chain after curing with ionizing radiation or the like. It is preferable that Moreover, it is preferable that the main binder polymer after hardening has a crosslinked structure.

  As the binder polymer having a saturated hydrocarbon chain as a main chain after curing, an ethylenically unsaturated monomer selected from compounds of the first group described below and a polymer thereof are preferable. Moreover, as a polymer which has a polyether chain as a principal chain, the epoxy-type monomer chosen from the compound of the 2nd group described below and the polymer by these ring-opening are preferable. Furthermore, a polymer of a mixture of these monomers is also preferable.

  In the present invention, as the first group of compounds, the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure is a (co) polymer of monomers having two or more ethylenically unsaturated groups. Is preferred. In order to obtain a high refractive index, the monomer structure preferably contains at least one selected from an aromatic ring, a halogen atom other than fluorine, a sulfur atom, a phosphorus atom, and a nitrogen atom.

  As the monomer having two or more ethylenically unsaturated groups used in the binder polymer, an ester of a polyhydric alcohol and (meth) acrylic acid {for example, ethylene glycol di (meth) acrylate, 1,4-cyclohexanedi Acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta ( (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-chlorohexane tetramethacrylate, polyurethane Reacrylate, polyester polyacrylate}, vinylbenzene and derivatives thereof (for example, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinyl sulfone (for example, divinyl sulfone) ), (Meth) acrylamide (for example, methylenebisacrylamide) and the like.

  Furthermore, resins having two or more ethylenically unsaturated groups, such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins And oligomers or prepolymers such as polyfunctional compounds such as polyhydric alcohols. Two or more of these monomers may be used in combination, and the resin having two or more ethylenically unsaturated groups is preferably contained in an amount of 10 to 100% based on the total amount of the binder polymer.

  Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photoradical polymerization initiator or a thermal radical polymerization initiator. Accordingly, a coating solution containing the above various components, a monomer having an ethylenically unsaturated group, and if necessary, an inorganic filler, a coating aid, other additives, an organic solvent, and the like is prepared, and the coating solution is used as a base film. After being coated on top, it is cured by a polymerization reaction with ionizing radiation or heat to form a hard coat layer. It is also preferable to perform ionizing radiation curing and thermal curing together. Commercially available compounds can be used as the photo and thermal polymerization initiators, and they are described in “Latest UV Curing Technology” (p. 159, publisher: Kazuhiro Takahisa, publisher; Technical Information Association, 1991). Issued) and Ciba Specialty Chemicals catalog.

  Further, as described above, the binder polymer preferably contains the following resins (A), (B) and (C).

(A) Component: at least one selected from urethane acrylate and urethane methacrylate (B) Component: at least one selected from polyol acrylate and polyol methacrylate (C) Component: selected from (C1) and (C2) below A polymer or copolymer formed from at least one of the above or a mixed polymer of the polymer and the copolymer (C1): an alkyl acrylate having an alkyl group having at least one of a hydroxyl group and an acryloyl group (C2): a hydroxyl group and an acryloyl Alkyl methacrylate having an alkyl group having at least one of the groups

  As said urethane acrylate and urethane methacrylate which are said (A) component, what contains acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, a polyol, and diisocyanate as a structural component is used. For example, by using at least one monomer of acrylic acid, methacrylic acid, acrylic acid ester and methacrylic acid ester and a polyol, at least one of hydroxy acrylate having one or more hydroxyl groups and hydroxy methacrylate having one or more hydroxyl groups is produced. Then, at least one of urethane acrylate and urethane methacrylate can be produced by reacting this with diisocyanate. In the component (A), one type of urethane acrylate or urethane methacrylate may be used alone, or two or more types may be used in combination.

  Examples of acrylic esters include alkyl acrylates such as methyl acrylate, ethyl acrylate, isopropyl acrylate, and butyl acrylate; cycloalkyl acrylates such as cyclohexyl acrylate, and the like. Examples of the methacrylic acid ester include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, and butyl methacrylate; cycloalkyl methacrylates such as cyclohexyl methacrylate.

  The polyol is a compound having at least two hydroxyl groups, such as ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol, 1,10-decanediol, 2,2,4-trimethyl-1,3-pentanediol, 3-methyl-1,5 -Pentanediol, hydroxypivalic acid neopentyl glycol ester, tricyclodecane dimethylol, 1,4-cyclohexanediol, spiroglycol, tricyclodecane dimethylol, hydrogenated bisphenol A, ethylene oxide-added bisphenol A, propylene glycol Side addition bisphenol A, trimethylolethane, trimethylolpropane, glycerin, 3-methylpentane-1,3,5-triol, pentaerythritol, dipentaerythritol, tripentaerythritol, glucose and the like can be mentioned.

  As said diisocyanate, various aromatic, aliphatic, or alicyclic diisocyanates can be used, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, 4 , 4-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 3,3-dimethyl-4,4-diphenyl diisocyanate, xylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, and hydrogenated products thereof Can be given.

  The mixing ratio of the component (A) is not particularly limited. By using the component (A), the flexibility of the hard coat layer to be formed and the adhesion to the film substrate can be improved. From these points and the viewpoint of the hardness of the hard coat layer, the blending ratio of the component (A) is, for example, in the range of 15 to 55 mass% with respect to the entire resin component in the hard coat layer forming material. Preferably, it is the range of 25-45 mass%. The whole resin component means the total amount of the component (A), the component (B) and the component (C), or, when other resin components are used, the total amount of the three components and the total amount of the resin component The same applies hereinafter.

  Examples of the component (B) include pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, 1,6-hexanediol acrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, penta Examples include erythritol tetramethacrylate, dipentaerythritol hexamethacrylate, and 1,6-hexanediol methacrylate. These may be used alone or in combination of two or more. For example, the polyol acrylate is preferably a monomer component made of a polymer of pentaerythritol triacrylate and pentaerythritol tetraacrylate and a mixed component containing pentaerythritol triacrylate and pentaerythritol tetraacrylate.

  The mixing ratio of the component (B) is not particularly limited. For example, the blending ratio of the component (B) is preferably in the range of 70 to 180% by mass, more preferably in the range of 100 to 150% by mass with respect to the component (A). When the blending ratio of the component (B) is 180% by mass or less with respect to the component (A), curing shrinkage of the formed hard coat layer can be effectively prevented, and as a result, curling of the film can be prevented and bending is achieved. It is possible to prevent a decrease in sex. Moreover, if the blending ratio of the component (B) is 70% by mass or more of the component (A), the hardness of the hard coat layer to be formed can be further improved, and the scratch resistance can be improved. It becomes.

  In the component (C), the alkyl group of (C1) and (C2) is not particularly limited, and is, for example, an alkyl group having 1 to 10 carbon atoms, which may be linear or branched. There may be. Examples of the component (C) include a polymer, a copolymer or a mixture of the polymer and the copolymer containing a repeating unit of the following general formula (1).

In the general formula (1), R ¹ is —H or —CH ₃ , R ² is —CH ₂ CH ₂ OX or a group represented by the following general formula (2), and X is -H or an acryloyl group represented by the following general formula (3).

  In the general formula (2), X is —H or an acryloyl group represented by the following general formula (3), and the Xs may be the same or different.

Examples of the component (C) include 2,3-dihydroxypropyl acrylate, 2,3-diacryloyloxypropyl acrylate, 2-hydroxy-3-acryloyloxypropyl acrylate, 2-acryloyloxy-3-hydroxypropyl acrylate, 2,3-dihydroxypropyl methacrylate, 2,3-diacryloyloxypropyl methacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, 2-acryloyloxy-3-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, 2-acryloyloxy At least one monomer selected from the group consisting of ethyl acrylate, 2-hydroxyethyl methacrylate and 2-acryloyloxy methacrylate; Formed polymer, a mixture of copolymer or the polymer and the copolymer can be mentioned.
The blending ratio of the component (C) is not particularly limited. For example, the blending ratio of the component (C) is preferably in the range of 25 to 110% by mass, more preferably in the range of 45 to 85% by mass with respect to the component (A). When the blending ratio of the component (C) is 110% by mass or less, the coating property of the antiglare hard coat layer forming material becomes excellent, and the blending ratio of the component (C) is 25% by mass or more. For example, curing shrinkage of the formed antiglare hard coat layer can be prevented.

In the present invention, the epoxy compound described below is preferably used as the second group of compounds in order to reduce the curing shrinkage of the cured film. As these monomers having an epoxy group, monomers having two or more epoxy groups in one molecule are preferable, and examples thereof include JP-A Nos. 2004-264563, 2004-264564, and 2005-37737, Examples thereof include epoxy monomers described in JP-A-2005-37738, JP-A-2005-140862, JP-A-2005-140862, JP-A-2005-140863, and JP-A-2002-322430.
The monomer having an epoxy group is preferably contained in an amount of 20 to 100% by mass with respect to all binders constituting the layer in order to reduce curing shrinkage, more preferably 35 to 100% by mass, and more preferably 50 to 100% by mass. It is more preferable to contain.

Examples of photoacid generators that generate cations by the action of light for polymerizing epoxy monomers and compounds include ionic compounds such as triarylsulfonium salts and diaryliodonium salts, and nitrobenzyl esters of sulfonic acids. Non-ionic compounds and the like can be used, and various known photoacid generators such as compounds described in “Organic Materials for Imaging” published by Bunshin Publishing Co., Ltd. (1997) can be used. . Among these, a sulfonium salt or an iodonium salt is particularly preferable, and PF ₆ ⁻ , SbF ₆ ⁻ , AsF ₆ ⁻ , B (C ₆ F ₅ ) ₄ ^{− and the} like are preferable as a counter ion.

  The polymerization initiator is preferably used in a range of 0.1 to 15 parts by mass with respect to 100 parts by mass of the compound of the first group or the second group in the total amount of the polymerization initiator. Is more preferable.

<High molecular compound of hard coat layer>
The hard coat layer of the present invention may contain a polymer compound. By adding a polymer compound, curing shrinkage can be reduced, and the viscosity of the coating solution can be adjusted.

  The polymer compound has already formed a polymer when added to the coating solution. Examples of the polymer compound include cellulose esters (for example, cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose acetate Pionate, cellulose acetate butyrate, cellulose nitrate, etc.), urethane acrylates, polyester acrylates, (meth) acrylic acid esters (for example, methyl methacrylate / (meth) methyl acrylate copolymer, methyl methacrylate / (Meth) ethyl acrylate copolymer, methyl methacrylate / (meth) butyl acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / (meth) acrylic acid copolymer, polymethyl methacrylate Etc.), poly Resins such as styrene are preferably used.

  The polymer compound is preferably from 1 to 50% by mass, more preferably from 5 to 5%, based on the total binder polymer contained in the layer containing the polymer compound, from the viewpoint of the effect on curing shrinkage and the effect of increasing the viscosity of the coating solution. It is preferable to contain in 40 mass%. Further, the molecular weight of the polymer compound is preferably from 30,000 to 400,000 in terms of mass average, more preferably from 50,000 to 300,000, and even more preferably from 50,000 to 200,000.

<Inorganic filler for hard coat layer>
In addition to the porous particles and translucent particles described above, the hard coat layer of the present invention adjusts the refractive index, adjusts the film strength, reduces curing shrinkage, and further reduces the reflectance when a low refractive index layer is provided. Depending on the purpose, an inorganic filler can also be used. For example, it is made of an oxide containing at least one metal element selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, and the average particle size of primary particles is generally 0.2 μm or less, preferably It is also preferable to contain a fine high refractive index inorganic filler that is 0.1 μm or less, more preferably 0.06 μm or less and 1 nm or more.

  When it is necessary to lower the refractive index of the matrix in order to adjust the difference in refractive index with the light-transmitting particles, a fine low refractive index inorganic filler such as silica fine particles or hollow silica fine particles is used as the inorganic filler. be able to. The preferred particle size is the same as that of the fine high refractive index inorganic filler.

  The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.

  It is preferable that the addition amount of an inorganic filler is 10-90 mass% of the total mass of a hard-coat layer, More preferably, it is 20-80 mass%, Most preferably, it is 30-75 mass%.

  In addition, since the inorganic filler has a particle size sufficiently shorter than the wavelength of light, scattering does not occur, and the dispersion in which the filler is dispersed in the binder polymer has the property of an optically uniform substance.

<Surfactant of hard coat layer>
In the hard coat layer of the present invention, in order to ensure surface uniformity such as coating unevenness, drying unevenness, point defects, etc., either a fluorine-based surfactant or a silicone-based surfactant or both of them is used for the hard coat layer. It is preferable to contain in the coating composition. In particular, a fluorine-based surfactant is preferably used because an effect of improving surface failure such as coating unevenness, drying unevenness, and point defect of the polarizing plate protective film of the present invention appears in a smaller addition amount.
The purpose is to increase productivity by giving high-speed coating suitability while improving surface uniformity. Preferable examples of the fluorine-based surfactant include compounds described in paragraph numbers 0049 to 0074 of JP2007-188070A.

  The preferable addition amount of the surfactant (particularly the fluoropolymer) used in the hard coat layer of the present invention is in the range of 0.001 to 5% by mass, preferably 0.005 to 3% by mass with respect to the coating solution. %, And more preferably in the range of 0.01 to 1% by mass. When the addition amount of the surfactant is 0.001% by mass or more, the effect is sufficient, and by setting the addition amount to 5% by mass or less, the coating film is sufficiently dried and good performance as a coating film (for example, reflection) Rate, scratch resistance).

<Organic solvent of coating liquid for hard coat layer>
An organic solvent can be added to the coating composition for forming the hard coat layer.

  As an organic solvent, for example, in an alcohol system, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, isoamyl alcohol, 1-pentanol, n-hexanol, methyl amyl alcohol In the ketone system, methyl isobutyl ketone, methyl ethyl ketone, diethyl ketone, acetone, cyclohexanone, diacetone alcohol, etc., in the ester system, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, n-butyl acetate, Isoamyl acetate, n-amyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, methyl acetate, methyl lactate, ethyl lactate, ether, acetal, 1,4 dioxane, te In hydrocarbons such as lahydrofuran, 2-methylfuran, tetrahydropyran, diethyl acetal, etc., hexane, heptane, octane, isooctane, ligroin, cyclohexane, methylcyclohexane, toluene, xylene, ethylbenzene, styrene, divinylbenzene, etc., halogen hydrocarbons In, carbon tetrachloride, chloroform, methylene chloride, ethylene chloride, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, tetrachloroethylene, 1,1,1,2-tetrachloroethane In the case of polyhydric alcohols and derivatives thereof, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoacetate, diethylene glycol, In fatty acid systems such as lenglycol, dipropylene glycol, butanediol, hexylene glycol, 1,5-pentanediol, glycerin monoacetate, glycerin ethers, 1,2,6-hexanetriol, formic acid, acetic acid, propionic acid, In the case of nitrogen compounds such as entrained acid, isoentangled acid, isovaleric acid, and lactic acid, formamide, N, N-dimethylformamide, acetamide, acetonitrile, and the like, and in the case of sulfur compounds, dimethyl sulfoxide and the like can be mentioned.

  Among organic solvents, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, acetone, toluene, xylene, ethyl acetate, 1-pentanol and the like are particularly preferable. In addition, an alcohol or a polyhydric alcohol solvent may be appropriately mixed with the organic solvent for the purpose of controlling cohesion. These organic solvents may be used alone or in combination, and the coating composition preferably contains 20% by mass to 90% by mass, and preferably 30% by mass to 80% by mass, as the total amount of the organic solvent. More preferably, it is most preferable to contain 40 mass%-70 mass%. In order to stabilize the surface shape of the hard coat layer, it is preferable to use a solvent having a boiling point of less than 100 ° C. and a solvent having a boiling point of 100 ° C. or more in combination.

<Hardening of hard coat layer>
The hard coat layer can be formed by applying a coating solution to a support, and then carrying out light irradiation, electron beam irradiation, heat treatment or the like to cause crosslinking or polymerization reaction. In the case of ultraviolet irradiation, ultraviolet rays emitted from light such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, etc. can be used. Curing with ultraviolet rays is preferably carried out by nitrogen purge or the like in an atmosphere having an oxygen concentration of 4% by volume or less, more preferably 2% by volume or less, and most preferably 0.5% by volume or less.

  Below, layers other than a hard-coat layer are demonstrated.

<Low refractive index layer>
The polarizing plate protective film of the present invention preferably has a low refractive index layer in order to reduce the reflectance. The refractive index of the low refractive index layer is preferably 1.20 to 1.46, more preferably 1.25 to 1.46, and particularly preferably 1.30 to 1.40. The thickness of the low refractive index layer is preferably 50 to 200 nm, and more preferably 70 to 100 nm. The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less.

As an aspect of a cured product composition for forming a preferable low refractive index layer,
(1) A composition containing a fluorine-containing polymer having a crosslinkable or polymerizable functional group,
(2) a composition comprising as a main component a hydrolysis-condensation product of a fluorine-containing organosilane material;
(3) a composition containing a monomer having two or more ethylenically unsaturated groups and inorganic fine particles having a hollow structure;
Is mentioned.

(1) Fluorine-containing compound having a crosslinkable or polymerizable functional group As the fluorine-containing compound having a crosslinkable or polymerizable functional group, co-polymerization of a fluorine-containing monomer and a monomer having a crosslinkable or polymerizable functional group Coalescence can be mentioned. Specific examples of these fluoropolymers are described in JP2003-222702A, JP2003-183322A, and the like.

  As described in JP 2000-17028 A, a curing agent having a polymerizable unsaturated group may be used in combination with the above polymer. Moreover, combined use with the compound which has a fluorine-containing polyfunctional polymerizable unsaturated group as described in Unexamined-Japanese-Patent No. 2002-145952 is also preferable. Examples of the compound having a polyfunctional polymerizable unsaturated group include the above-described monomers having two or more ethylenically unsaturated groups. Moreover, the hydrolysis-condensation product of the organolane described in Unexamined-Japanese-Patent No. 2004-170901 is also preferable, and the hydrolysis-condensation product of the organosilane containing a (meth) acryloyl group is especially preferable. These compounds are particularly preferred because they have a large combined effect for improving scratch resistance, particularly when a compound having a polymerizable unsaturated group is used in the polymer body.

  When the polymer itself does not have sufficient curability, necessary curability can be imparted by blending a crosslinkable compound. For example, when the polymer body contains a hydroxyl group, various amino compounds are preferably used as the curing agent. The amino compound used as the crosslinkable compound is, for example, a compound containing one or both of a hydroxyalkylamino group and an alkoxyalkylamino group in total, specifically, for example, a melamine compound, Examples include urea compounds, benzoguanamine compounds, glycoluril compounds, and the like. For curing these compounds, an organic acid or a salt thereof is preferably used.

(2) Hydrolyzed condensate of fluorine-containing organosilane material A composition containing a hydrolyzed condensate of a fluorine-containing organosilane compound as a main component is also preferable because of its low refractive index and high hardness on the coating film surface. A condensate of a tetraalkoxysilane with a hydrolyzable silanol-containing compound at one or both ends with respect to the fluorinated alkyl group is preferred. The specific composition is described in Unexamined-Japanese-Patent No. 2002-265866, 317152.

(3) A composition containing a monomer having two or more ethylenically unsaturated groups and inorganic fine particles having a hollow structure As yet another preferred embodiment, a low refractive index layer comprising low refractive index particles and a binder can be mentioned. . The low refractive index particles may be organic or inorganic, but particles having pores inside are preferable. Specific examples of the hollow particles are described in the silica-based particles described in JP-A-2002-79616. The particle refractive index is preferably 1.15 to 1.40, more preferably 1.20 to 1.30. Examples of the binder include monomers having two or more ethylenically unsaturated groups described on the page of the antiglare layer.

  It is preferable to add the polymerization initiator described on the hard coat layer page to the low refractive index layer of the present invention. When a radically polymerizable compound is contained, 1 to 10 parts by mass, preferably 1 to 5 parts by mass of a polymerization initiator can be used with respect to the compound.

  In the low refractive moisture layer of the present invention, inorganic particles can be used in combination. In order to impart scratch resistance, fine particles having a particle size of 15% to 150%, preferably 30% to 100%, more preferably 45% to 60% of the thickness of the low refractive index layer can be used. .

  In the low refractive index layer of the present invention, for the purpose of imparting properties such as antifouling property, water resistance, chemical resistance, and slipping property, a known polysiloxane-based or fluorine-based antifouling agent, slipping agent, etc. are appropriately used. Can be added.

  In the present invention, the preferred integrated reflectance of the polarizing plate protective film provided with a low refractive index layer or the like is preferably 3.0% or less, more preferably 2.0% or less, and most preferably 1.5% or less. It is 0.3% or more. Since sufficient antiglare property can be obtained even if light scattering on the surface of the film is reduced by lowering the integrated reflectance, a polarizing plate protective film excellent in black tightening can be obtained.

<Film base material>
As a film substrate of the polarizing plate protective film of the present invention, it is preferable to use a plastic film. Examples of the polymer forming the plastic film include cellulose acylate (eg, triacetyl cellulose, diacetyl cellulose, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Film), polyamide, polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene). Naphthalate), polystyrene, polyolefin, norbornene resin (Zeonor: trade name, manufactured by Nippon Zeon Co., Ltd. Arton: trade name, manufactured by JSR), (meth) acrylic resin (Acrypet VRL20A: trade name, manufactured by Mitsubishi Rayon Co., Ltd.) Examples thereof include ring structure-containing acrylic resins described in JP-A No. 2004-70296 and JP-A No. 2006-171464. Of these, cellulose acylate, polyethylene terephthalate, and polyethylene naphthalate are preferable, and cellulose acylate is particularly preferable.
In addition to the polarizing plate protective film having the hard coat layer of the present invention, the other polarizing plate protective film is preferably a plastic film. Examples of the polymer forming the plastic film include cellulose acylate, polyamide, polycarbonate, polyester, polystyrene, polyolefin, norbornene resin, (meth) acrylic resin, and the like. Of these, norbornene resins are preferred.

  The polarizing plate protective film of the present invention is used in a liquid crystal display device and disposed on the outermost surface of the display by providing an adhesive layer on one side.

Although the thickness of the film base material of the polarizing plate protective film is not particularly limited, it is, for example, in the range of 5 to 100 μm from the viewpoints of workability such as strength, handleability, and thin layer properties. If it is the said range, a polarizer will be protected mechanically, and even if it exposes to high temperature and high humidity, a polarizer will not shrink | contract and it can maintain the stable optical characteristic. The thickness of the film substrate is preferably in the range of 10 to 80 μm, more preferably in the range of 20 to 70 μm, from the preferable range of moisture permeability.

When the polarizing plate protective film of the present invention is disposed on the outermost surface of the display by providing an adhesive layer on one side, or when used as it is as a polarizing plate protective film, it is a film base material for sufficient adhesion. It is preferable to carry out a saponification treatment after the outermost layer is formed thereon. The saponification treatment is performed by a known method, for example, by immersing the film in an alkali solution for an appropriate time. After being immersed in the alkaline solution, it is preferable to sufficiently wash with water or neutralize the alkaline component by dipping in a dilute acid so that the alkaline component does not remain in the film.
By performing the saponification treatment, the surface of the film base opposite to the side having the outermost layer is hydrophilized.

<Application method>
Although the polarizing plate protective film of this invention can be formed with the following method, it is not restrict | limited to this method. First, a coating solution containing components for forming each layer is prepared. Next, a coating solution for forming a functional layer having various functions is applied on the transparent support by dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, or die coating. The microgravure coating method, the wire bar coating method, and the die coating method (see US Pat. No. 2,681,294 and JP-A-2006-122889) are more preferable, and the die coating method is particularly preferable.

  Thereafter, the monomer for forming the functional layer is polymerized and cured by light irradiation or heating. Thereby, a functional layer is formed. If necessary, the functional layer can be a plurality of layers.

  Next, a coating solution for forming a low refractive index layer is applied onto the functional layer in the same manner, and is irradiated with light or heated (irradiated with ionizing radiation such as ultraviolet rays, preferably irradiated with ionizing radiation under heating. Cured) to form a low refractive index layer. Thus, the polarizing plate protective film of the present invention is obtained.

<Polarizing plate>
The polarizing plate is mainly composed of two protective films that protect both the front and back sides of the polarizer. The polarizing plate protective film of the present invention is preferably used on one side of two protective films sandwiching the polarizer from both sides. Moreover, by using the polarizing plate protective film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, antifouling property, and the like can be obtained.

The hydrophilized surface is particularly effective for improving the adhesion with a polarizer mainly composed of polyvinyl alcohol. In addition, the hydrophilic surface makes it difficult for dust in the air to adhere to it, so that it is difficult for dust to enter between the polarizer and the polarizing plate protective film when bonded to the polarizer, thereby preventing point defects due to dust. It is effective for.
The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent support opposite to the side having the outermost layer is 40 ° or less. More preferably, it is 30 ° or less, particularly preferably 20 ° or less.

<Image display device>
The polarizing plate protective film of the present invention is an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence display (ELD), a cathode ray tube display device (CRT), or a surface electric field display (SED). Can be applied to. It is particularly preferably used for a liquid crystal display (LCD). Since the polarizing plate protective film of the present invention has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

  When the polarizing plate protective film of the present invention is used as one side of a surface protective film of a polarizer, twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), It can be preferably used for a transmissive, reflective, or transflective liquid crystal display device of a mode such as an optically compensated bend cell (OCB).

  In order to describe the present invention in detail, examples will be described below, but the present invention is not limited thereto. Unless otherwise specified, “part” and “%” are based on mass.

<Composition of coating solution for antiglare hard coat layer>
Resin raw material containing (A) component, (B) component, (C) component, photopolymerization initiator and mixed solvent shown below (solid content concentration: 66% by mass, manufactured by Dainippon Ink Co., Ltd., trade name GRANDIC PC1097: resin 1) was prepared. To 100 parts by mass of the solid content of this resin raw material, 27 parts by mass of the following average particle size 8 μm particles, 8.1 parts by mass of particles (particles A, B, C or D) shown in Table 1 below and a leveling agent ( Dainippon Ink Co., Ltd., trade name GRANDIC PC-F479) 0.1 parts by mass is mixed and mixed, and this mixture is diluted with a solvent (ethyl acetate) so that the solid content concentration becomes 55% by mass. Thus, a coating solution for an antiglare hard coat layer was prepared.

Component (A): Isophorone diisocyanate urethane acrylate (100 parts by mass)
Component (B): dipentaerythritol hexaacrylate (38 parts by mass), pentaerythritol tetraacrylate (40 parts by mass) and pentaerythritol triacrylate (15.5 parts by mass)
Component (C): a polymer having a repeating unit represented by the general formula (1) (R ¹ is —CH ₃ , R ² is a group represented by the general formula (2), and X is the general formula ( 3) acryloyl group represented by (30 parts by mass)
Photopolymerization initiator: 1.8 parts by mass of trade name Irgacure 184 (manufactured by Ciba Specialty Chemicals) and 5.6 parts by mass of lucillin type photopolymerization initiator; butyl acetate: ethyl acetate (mass ratio) = 3: 4

Average particle size 8μm particles (translucent particles)
The following Sekisui Plastics Co., Ltd. product was used.
8 μm crosslinked acrylic-styrene particles: refractive index 1.56 (acrylic / styrene ratio: 3/7)

Production of porous particles A Production of seed particles:
A 1 L separable flask was charged with 90.7 parts by mass as swelling monomers, 1.3 parts by mass of benzoyl peroxide, 0.7 parts by mass of sodium dodecylbenzenesulfonate, and 200 ml of water and emulsified with a homogenizer. . To this, 9.3 parts by mass of 0.4 μm PMMA seed particles (MP-1100: manufactured by Soken Chemical Co., Ltd.) was added and swollen at 50 ° C. for 40 minutes while stirring at 80 rpm. This was further polymerized with stirring at 75 ° C. for 1.5 hours to produce seed particles. When the obtained seed particles were observed with an SEM, the average particle size was 2.9 μm.

  In a separable flask, a monomer mixture containing 95 parts by weight of methyl methacrylate and 5 parts by weight of divinylbenzene, 1.3 parts by weight of benzoyl peroxide, 0.7 parts by weight of an emulsifier (TP-BN-2070M: manufactured by Teika) and water 200 parts by mass was added and emulsified with a homogenizer. To this was added 2.5 parts by mass of the seed particles prepared as described above, and the mixture was swollen at 50 ° C. for 40 minutes while stirring. To this, 0.5 part by mass of polyvinyl alcohol was added, and the mixture was subsequently stirred to swell 40 times. After swelling, 1.5 parts by mass of polyvinyl alcohol was further added, followed by polymerization at 75 ° C. for 1.5 hours with stirring to produce monodispersed porous particles. After completion of the polymerization, the polymerization solution was filtered, and further washed and filtered twice in the order of an aqueous isopropyl alcohol solution and water to remove the monomer and the emulsifier, thereby obtaining particles A.

  When the particle A obtained above was observed with an SEM and the particle size was measured, it was 10 μm spherical and porous.

Preparation of Porous Particle B A polyamide 6 solution having a polyamide 6 concentration of 5 mass% was prepared by adding polyamide 6 (molecular weight 13,000) and dissolving it in a solution containing phenol and methanol in a mass ratio of 9: 1. . To this nylon solution, a mixed solution in which methanol and water were mixed at a mixing ratio of 8: 0.5 was added. The temperature was 30 ° C. The mixture was allowed to stand for 24 hours to complete the precipitation. Thereafter, the polymer was isolated by centrifugal separation, and then centrifugal dehydration was performed while applying methanol at 50 ° C. 100 times the amount of fine particles to wash the particles. When the obtained polymer particles were observed with a scanning electron microscope, they were spherical porous particles B having an average particle diameter of 10 μm.

Particle C
Particles were prepared in the same manner as the porous particles A, except that the seed particles used in the porous particles A were used as the resin particles, and a mixture of 95 parts by mass of styrene and 5 parts by mass of divinylbenzene was used as the monomer mixture. As a result of evaluating the obtained particles in the same manner as the porous particles A, it was monodispersed, the shape was spherical, non-porous, and the average particle size was 10 μm.

Particle D
A mixture obtained by mixing 5% by mass of a mass resin of polyamide 6 used for preparation of porous particles B with ethylene glycol was mixed in a mixing tank equipped with a stirrer at 230 ° C. until polyamide 6 was completely dissolved. Stir for 30 minutes. The resulting solution was cooled at a rate of 8 ° C./min. During this cooling process, the polyamide 6 was phase-separated into independent monospherical crystals. Only the ethylene glycol was washed out of the phase-separated mixture with water. After thoroughly washing three or more times, filtration and drying were performed to obtain polyamide 6 spherical particle powder. As a result of confirming the size of the obtained spherical particle powder using an electron microscope, the average particle size of the spherical particles D was 10 μm. The spherical particles D were non-porous.

Composition of coating liquid L-1 for low refractive index layer Ethylenically unsaturated group-containing fluorine-containing polymer (A-1) 3.9 g
Silica dispersion A (22%) 25.0 g
Irgacure 127 0.2g
DPHA 0.4g
MEK (methyl ethyl ketone) 100.0 g
MIBK (methyl isobutyl ketone) 45.5g

The coating solution for the low refractive index layer was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution.
The refractive index after curing of the low refractive index layer obtained by coating and curing the coating solution was 1.36.

The compounds used are shown below.
DPHA: a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate [manufactured by Nippon Kayaku Co., Ltd.];
Irgacure 127: Polymerization initiator [Ciba Specialty Chemicals Co., Ltd.];
Ethylenically unsaturated group-containing fluorine-containing polymer (A-1): polymer described in Example Production Example 3 of JP-A-2005-89536

(Silica dispersion A)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20 mass%, silica particle refractive index 1.31, change size according to Preparation Example 4 of JP-A-2002-79616. Prepared) 10 g of acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) and 1.0 g of diisopropoxyaluminum ethyl acetate were added and mixed, and then 3 g of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.0 g of acetylacetone. While adding cyclohexanone to 500 g of this dispersion so that the content of silica was almost constant, solvent substitution by vacuum distillation was performed. There was no generation of foreign matter in the dispersion, and the viscosity when the solid content concentration was adjusted to 22% by mass with cyclohexanone was 5 mPa · s at 25 ° C. When the residual amount of isopropyl alcohol in the obtained dispersion A was analyzed by gas chromatography, it was 1.0%.

[Example 1]
Preparation of Polarizing Plate Protective Film Sample 101 (1) Coating of Antiglare Hard Coat Layer An antiglare hard coat layer coating solution shown in Table 1 unrolled in a roll form with a thickness of 60 μm in triacetyl cellulose film. In the die coating method using the slot die described in Example 1 of JP-A-2006-122889, coating was performed under the condition of a conveyance speed of 30 m / min, drying at 60 ° C. for 150 seconds, and further oxygen concentration under nitrogen purge Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of about 0.1%, UV irradiation with an illuminance of 400 mW / cm ² and an irradiation amount of 100 mJ / cm ² is used to cure and wind the coating layer. I took it. The coating amount was adjusted so that the film thickness of the antiglare hard coat layer was the value shown in Table 1.

(2) Coating of low refractive index layer The triacetyl cellulose film coated with the antiglare hard coat layer was unwound again, and the coating liquid L-1 for the low refractive index layer was used using the slot die. After coating at a transfer speed of 30 m / min by a die coating method, drying at 90 ° C. for 75 seconds, and an air-cooled metal halide lamp (I graphics ( Was used to irradiate ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 240 mJ / cm ² to form a low refractive index layer having a thickness of 100 nm and wound up to prepare a polarizing plate protective film.

(Saponification treatment of polarizing plate protective film)
After coating, the sample was subjected to the following treatment. A 1.5 mol / L aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.01 mol / L dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The produced polarizing plate protective film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the above-mentioned dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
In this way, a saponified polarizing plate protective film (Sample 101) was produced.

  Hereinafter, similarly, according to the conditions shown in Table 1, polarizing plate protective films (samples 102 to 116) were produced.

(Preparation of polarizing plate)
A polarizing plate was prepared by adhering and protecting both sides of a polarizer prepared by adsorbing iodine to polyvinyl alcohol on each sample film (saponified) and the following norbornene-based resin film and stretching the film. A PVA adhesive was used for adhesion between the sample and polyvinyl alcohol, and an isocyanate adhesive was used for adhesion between the norbornene resin film and polyvinyl alcohol.
A norbornene-based resin film: a norbornene-based resin film (manufactured by Nippon Zeon Co., Ltd .: trade name ZEONOR: thickness 60 μm) was used as a uniaxially stretched film. The thickness was 54 μm, the in-plane retardation Re ₁ was 55 nm, and the thickness direction retardation Re ₂ was 120 nm.

(Evaluation of polarizing plate protective film and polarizing plate)
About these obtained polarizing plate protective film samples and polarizing plates, the following items were evaluated. The results are shown in Table 1.

<Measurement of moisture permeability of polarizing plate protective film>
As described above, in the present invention, the moisture permeability of the polarizing plate protective film was calculated according to JIS Z-0208 except that the humidity control condition was changed to 60 ° C. and 95% RH. At this time, the operation of taking out and weighing the cup placed in the thermo-hygrostat at an appropriate time interval is repeated, and the mass increase per unit time is obtained for each of two consecutive weighings, and it is constant within 5%. Evaluation continued until.
Moreover, in order to exclude the influence by the moisture absorption etc. of a sample, the blank cup which does not put a hygroscopic agent was measured, and the value of moisture permeability was correct | amended.

<Discoloration of polarizing plate>
An adhesive was applied to the norbornene resin film side of the polarizing plate of the present invention, and the side having the adhesive was attached to a glass plate.
The polarizing plate attached to the glass plate is exposed to a condition of 23 ° C. and 95% RH for 7 days, then left to stand at a temperature of 25 ° C. and 60% RH for 1 day, and transmitted to a sample that has not been exposed to 23 ° C. and 95% RH for 7 days. The presence or absence of light color change was visually evaluated as follows.
○: The difference in color is not visible visually. Δ: The color difference is slightly visible.
×: The difference in color is clearly visible

<Polarizing plate durability>
An adhesive was applied to the norbornene resin film side of the polarizing plate of the present invention, and the side having the adhesive was attached to a glass plate.
The polarizing plate attached to the glass plate was exposed for 1 day at 50 ° C. and 90% RH, and then left for 1 day at 25 ° C. and 60% RH. Samples that have not been exposed to 50 ° C. and 90% RH for one day have transmittance Ii measured in an arrangement in which the polarizing plate transmission axes are orthogonal to each other, and samples that have been exposed to 50 ° C. and 90% for one day have an arrangement in which the polarizing plate transmission axes are orthogonal. With the measured transmittance Io, the transmittance change (difference between Io and Ii) was evaluated as follows.
○: Change in transmittance less than 0.001%
Δ: Change in transmittance 0.001% to 0.005%
X: Change in transmittance greater than 0.005%

<Pencil hardness of polarizing plate protective film>
The strength of the polarizing plate protective film of the present invention was evaluated by a pencil hardness test according to JIS-K5400.
: 5H
○: 4H
Δ: 3H

  The evaluation results are shown in Table 1.

  In Table 1, PET-30 is a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate [manufactured by Nippon Kayaku Co., Ltd.].

  From the results shown in Table 1, the following is clear. The polarizing plate protective film of the present invention is a film having excellent pencil hardness, discoloration of the polarizing plate at normal temperature and high humidity, and excellent polarizing plate durability at high temperature and high humidity.

[Example 2]
The polarizing plate produced in Example 1 (Sample No. 101) was replaced with the polarizing plate on the viewing side of the Sharp TV equipped with a transmission type VA liquid crystal display device so that the low refractive index layer was the outermost surface ( When the test was performed under the conditions of discoloration of the polarizing plate of Example 1 and the durability of the polarizing plate, the light was not leaked in the black display and the luminance was not lowered in the white display. As a result, a display device with excellent durability was obtained.

Claims (14)

A polarizing plate protective film having a hard coat layer on at least one surface on a film substrate, wherein the hard coat layer has a thickness of 10 μm or more and 40 μm or less, and moisture permeability of the film provided with the hard coat layer but under conditions of ^{RH 65 ℃ 95%, 700g /} m 2 / day or more, the polarizer protective film is less than 2500g ^/ m 2 ^/ day.   The polarizing plate protective film according to claim 1, wherein the hard coat layer contains porous particles.   The polarizing plate protective film according to claim 1, wherein the porous particles are acrylic resin particles containing polymethyl methacrylate or methyl methacrylate as a copolymerization component.   The polarizing plate protective film according to claim 1, wherein the porous particles are polyamide porous particles.   The polarizing plate protective film according to claim 1, wherein a mass average particle diameter of the porous particles is in a range of 30 to 120% with respect to a thickness of the hard coat layer.   The polarizing plate protective film according to any one of claims 1 to 5, wherein the porous particles are contained in an amount of 5 to 10 parts by mass with respect to 100 parts by mass of the resin forming the hard coat layer.   The said film base material is a cellulose acylate, The polarizing plate protective film in any one of Claims 1-6.   The polarizing plate protective film according to claim 1, wherein the film substrate has a thickness of 20 μm to 70 μm.   The said hard-coat layer contains translucent particle | grains, The average particle diameter of the said translucent particle | grain is the range of 30 to 75% of the thickness of the said hard-coat layer. Polarizing plate protective film. The polarizing plate according to claim 1, wherein the hard coat layer is formed using a composition for forming a hard coat layer containing the following component (A), component (B), and component (C): Protective film.
(A) Component: at least one selected from urethane acrylate and urethane methacrylate (B) Component: at least one selected from polyol acrylate and polyol methacrylate (C) Component: selected from (C1) and (C2) below A polymer or copolymer formed from at least one of the above or a mixed polymer of the polymer and the copolymer (C1): an alkyl acrylate having an alkyl group having at least one of a hydroxyl group and an acryloyl group (C2): a hydroxyl group and an acryloyl Alkyl methacrylate having an alkyl group having at least one of the groups   Furthermore, the polarizing plate protective film in any one of Claims 1-10 in which the antireflection layer is formed on the said hard-coat layer.   It is a polarizing plate containing a polarizer, Comprising: Furthermore, the polarizing plate containing the polarizing plate protective film in any one of Claims 1-11.   It is a polarizing plate containing a polarizer, Comprising: One polarizing film of this polarizing plate is a norbornene-type resin film, and the polarizing plate which is a polarizing plate protective film in any one of Claims 1-11.   The image display apparatus which has a polarizing plate protective film in any one of Claims 1-11, or the polarizing plate of Claim 12 or 13.