KR20180121977A - Flexible polarizing film, manufacturing method thereof, and image display device - Google Patents

Abstract

The present invention relates to a polyvinyl alcohol-based polarizer having a polyvinyl alcohol-based resin having a thickness of 10 占 퐉 or less and having a polyvinyl alcohol-based resin oriented in one direction and iodine or a dichroic dye adsorbed and oriented on the polyvinyl alcohol- And a reinforcing film closely adhered to the polyvinyl alcohol polarizer on at least one side of the polyvinyl alcohol polarizer. Although the flexible polarizing film of the present invention uses a polyvinyl alcohol polarizer, it has a high degree of flexibility (flexibility).

Description

Flexible polarizing film, manufacturing method thereof, and image display device

The present invention relates to a flexible polarizing film and a manufacturing method thereof. The flexible polarizing film can form an image display device such as a liquid crystal display (LCD), an organic EL display or the like as an optical film alone or in a laminated form thereof.

It is indispensable to arrange the polarizers on both sides of the glass substrate forming the surface of the liquid crystal panel from the image forming system in the liquid crystal display apparatus. As the polarizer, a polyvinyl alcohol-based polarizer in which a polyvinyl alcohol-based resin is oriented in one direction and an iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-based resin is used . However, there is a problem that the polyvinyl alcohol-based polarizer tends to be torn easily in a single body. Particularly, the polyvinyl alcohol polarizer tends to be torn in parallel in the direction in which the polyvinyl alcohol-based resin is oriented (absorption axis direction). For example, if an external force for shrinking in the absorption axis direction is applied, the polyvinyl alcohol polarizer tears very easily.

Therefore, the polyvinyl alcohol polarizer is generally used as a polarizing film in which a transparent protective film is bonded (joined) to one or both sides thereof.

As other polarizers, there are known polyvinyl alcohol polarizers as well as grid polarizers (Patent Documents 1 and 2).

Japanese Patent Application Laid-Open No. 2005-316495 Japanese Patent Application Laid-Open No. 2007-232792

However, a general polarizing film using a polyvinyl alcohol polarizer has rigidity (elasticity) and lacks flexibility (flexibility) because a transparent protective film is adhered thereto. Therefore, when twisting is applied to the polarizing film, the use of the polarizing film is limited due to cracks or cracks in the entire film, a folded trace (folded trace) remains, and light leakage occurs in the polarizer. On the other hand, the grid polarizer is flexible but lacks versatility.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flexible polarizing film having a high degree of flexibility and a method for producing the same, in spite of using a polyvinyl alcohol polarizer.

It is still another object of the present invention to provide an image display apparatus having the above-described flexible polarizing film.

The present inventors have intensively studied and found that the above problems can be solved by the following flexible polarizing film and the like, and have reached the present invention.

That is, the present invention provides a polyvinyl alcohol-based polarizer having a thickness of 10 탆 or less, wherein the polyvinyl alcohol-based resin is oriented in one direction and the iodine or the dichroic dye is adsorbed and oriented on the polyvinyl alcohol- Wherein the flexible flat film has a reinforcing film adhered to at least one surface of the polyvinyl alcohol polarizer in close contact with the polyvinyl alcohol polarizer.

In the flexible polarizing film, the thickness of the reinforcing film is preferably 15 탆 or less.

It is preferable that the flexible polarizing film has a first reinforcing film of 15 mu m or less in thickness on the first side of the polyvinyl alcohol polarizer and a second reinforcing film of 15 mu m or less in thickness on the other side of the second polarizing film. The difference in thickness between the first reinforcing film and the second reinforcing film is preferably 10 탆 or less.

In the flexible polarizing film, the ratio of the thickness of the reinforcing film to the thickness of the polyvinyl alcohol polarizer is preferably 0.4 or more.

In the flexible polarizing film, the reinforcing film preferably has a compressive modulus at 23 캜 of 1 MPa or more.

In the flexible polarizing film, the reinforcing film may be substantially not oriented.

In the flexible polarizing film, a resin film may be used as the reinforcing film. It is preferable that the resin film is formed of a thermosetting resin or an active energy ray-curing resin.

In the flexible polarizing film, it is preferable that after the bit is twisted (twisted or twisted) in the direction in which the polyvinyl alcohol-based resin is oriented, there is no cracks, folded marks and light leakage.

In the flexible polarizing film, a U-shaped stretching test is repeated in which the stretching is repeated in a U-shape in an orientation direction in which the polyvinyl alcohol resin is oriented and in a direction orthogonal to the orientation direction, , Folded marks and no leakage light.

In the flexible polarizing film, after the bending and holding test in which the polyvinyl alcohol-based resin is bent and held in the alignment direction in which the polyvinyl alcohol-based resin is bent and in a direction orthogonal to the alignment direction is performed, the bending shape is maintained in either direction It is preferable that no cracks occur at the same time.

In the above flexible polarizing film, it is preferable that the laminating degree (mm) is 60 mm or less in the alignment direction in which the polyvinyl alcohol-based resin is oriented and in the rigidity test in a direction perpendicular to the alignment direction .

In the flexible polarizing film, it is preferable that the tensile strength in the direction orthogonal to the alignment direction in which the polyvinyl alcohol-based resin in the tensile test is oriented is 5 N / 10 mm or more.

In the flexible polarizing film, the polyvinyl alcohol polarizer preferably has an optical characteristic represented by a single transmittance (T) and a degree of polarization (P)

P > - (10 ^0.929 T ^-42.4 -1) x 100 (T <42.3), or

P? 99.9 (where T? 42.3).

Further, the present invention is a method for producing the flexible polarizing film,

(1) a step of preparing a polyvinyl alcohol polarizer having a thickness of 10 탆 or less in which a polyvinyl alcohol-based resin is oriented in one direction and iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-

(2) of coating a liquid material containing a curable component that can constitute a resin component or a resin film on at least one surface of the polyvinyl alcohol polarizer, and thereafter solidifying or curing the liquid material to form a reinforcing film And a method of manufacturing a flexible polarizing film.

The present invention also relates to an image display apparatus having the above-described flexible polarizing film.

The flexible polarizing film of the present invention uses a polyvinyl alcohol polarizer and can satisfy general purpose. Further, the polyvinyl alcohol polarizer is preferably 10 μm or less in thickness and thinned.

In addition, the flexible polarizing film of the present invention has a high degree of flexibility even though a polyvinyl alcohol polarizer which tends to be torn and tends to be used in itself, has a high degree of flexibility, and even if the shape is deformed by twisting, A folded mark (folded trace) remains or no light is generated in the polarizer. Further, the flexible polarizing film of the present invention can have flexibility for various deformation such as stretching and bending. As described above, in the flexible polarizing film of the present invention, the polarizing film itself has flexibility, and the ordinary polyvinyl alcohol polarizers alone have a remarkably reduced tensile breaking stress and can not be practically handled. On the other hand, great.

Further, the flexible polarizing film of the present invention has flexibility even when it is used in combination with other members by utilizing flexibility or when it is used in combination, and can suppress cracking of the polarizer and can be used for various applications. Therefore, the use of the flexible polarizing film is greatly widened by expanding the use of the flexible polarizing film as a single unit or increasing the tolerance in the process. Therefore, the flexible polarizing film of the present invention can cope with a design which can not be applied because it is easily torn and torn by a conventional polarizer, for example, as a substitute for a polarizer, and a polarizing film (a polarizing film provided with a transparent protective film ), It is possible to cope with various deformed shapes that could not be applied, for example, because of the rigidity of a conventional polarizing film, and it is possible to expand the use of the polarizing film.

1 is an example of a schematic sectional view of a flexible polarizing film of the present invention.
Fig. 2 is a schematic view showing a state of twist in a twist (twist) test. Fig.
Fig. 3 is a schematic view showing the state of the U-shape in the U-shaped elastic shrinkage test.
4 is a schematic view showing the bending state in the bending holding test.
Fig. 5 is a schematic view showing the ladder diagram in the lubrication test.
6 is a schematic view showing a tensile test.

 Hereinafter, the flexible polarizing film of the present invention will be described. The flexible polarizing film of the present invention has a polyvinyl alcohol polarizer.

Hereinafter, an example of the flexible polarizing film of the present invention will be described with reference to Fig.

As the flexible polarizing film of the present invention, for example, one having a reinforcing film on at least one side of a polyvinyl alcohol polarizer can be used. The flexible polarizing film 1 of Fig. 1 (A) may have the first reinforcing film b1 only on the first one side of the polyvinyl alcohol polarizer (a). The flexible polarizing film 1 of Fig. 1 (B) 1) has a first reinforcing film b1 on the first surface of the polyvinyl alcohol polarizer 1 and a second reinforcing film b2 on the second surface. In the flexible polarizing film (1) of the present invention, the first reinforcing film (b1) and the second reinforcing film (b2) are provided directly on the polyvinyl alcohol polarizer (1).

Specifically, it is preferable that the flexible polarizing film of the present invention is capable of suppressing cracks, occurrence of folded marks, and leakage of light in the polyvinyl alcohol polarizer after performing the twist test shown in the examples. The torsion test is an index showing the flexibility in the twisted state of the alignment direction (absorption axis direction) in which the polyvinyl alcohol-based resin, which is prone to occurrence of cracks, folded marks, and leaked light, is oriented. It can be seen that the flexible polarizing film of the present invention has excellent flexibility in a twisted state without occurrence of cracks, folding marks and light leakage in the twist test.

It is preferable that the flexible polarizing film of the present invention is capable of suppressing cracking, occurrence of folded marks, and leakage of light after specifically performing the U-axis elongation and shrinkage test described in the examples. The U-stretch elongation test is an index showing the flexibility relating to the bending property at no load (no load) on the U-shape in the alignment direction (absorption axis direction) in which the polyvinyl alcohol type resin is oriented and in the orthogonal direction thereof (transmission axis direction). It can be seen that the flexible polarizing film of the present invention has flexibility relating to bending property at excellent no load in either the absorption axis direction or the transmission axis direction by suppressing cracks, occurrence of folded marks, and leakage of light in the U- have.

Specifically, it is preferable that the flexible polarizing film of the present invention keeps the bent shape and suppresses cracking after the bending and holding test shown in the embodiment is performed. The bending fatigue test is carried out in such a manner that even when the bending fatigue test is bent and bent in the alignment direction (absorption axis direction) in which the polyvinyl alcohol resin is oriented and in the orthogonal direction (transmission axis direction) It is an indicator of flexibility related to sustainability. It can be seen that the flexible polarizing film of the present invention maintains the bent shape in the bending retention test and suppresses cracking, thereby having excellent retentivity in both the absorption axis direction and the transmission axis direction.

It is preferable that the flexible polarizing film of the present invention specifically satisfies a laminating degree (mm) of 60 mm or less in the laminating property test shown in the examples. The lubrication property test is an index showing the flexibility related to the bending conformability (low resistance to bending) in the alignment direction (absorption axis direction) in which the polyvinyl alcohol type resin is oriented and in the orthogonal direction (transmission axis direction) thereof. It can be seen that the flexible polarizing film of the present invention has flexibility with respect to the bendability (low resistance to bending) and the lubrication degree is 60 mm or less. In addition, the above-mentioned polish degree (mm) is an index showing the above flexibility, preferably 50 mm or less, further preferably 40 mm or less. On the other hand, the lower limit of the laminating degree (mm) is not particularly limited.

It is preferable that the flexible polarizing film of the present invention specifically satisfies a tensile strength of 5 N / 10 mm or more in the tensile test shown in the examples. The tensile test is an index showing the strength in the direction (transmission axis direction) perpendicular to the alignment direction (absorption axis direction) in which the polyvinyl alcohol type resin is oriented. It can be seen that the flexible polarizing film of the present invention has the strength in the transmission axis direction when the tensile strength satisfies 5 N / 10 mm or more. The tensile strength is preferably 7 N / 10 mm or more, more preferably 10 N / 10 mm or more from the viewpoint of strength.

As described above, the flexible polarizing film 1 of the present invention is flexible and has a polarizing film which has a transparent protective film or the like on one side or both sides of the polyvinyl alcohol polarizer (a) Is clearly distinguished.

&Lt; Polyvinyl alcohol polarizer >

The polyvinyl alcohol polarizer is one in which a polyvinyl alcohol-based resin is oriented in one direction (absorption axis direction) and iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-based resin. Examples of the polyvinyl alcohol-based resin include polyvinyl alcohol, partially-formalized polyvinyl alcohol, and partially saponified ethylene-vinyl acetate copolymer system. The polarizer can be obtained by causing a polyvinyl alcohol film using the polyvinyl alcohol-based resin to adsorb a dichroic dye of iodine or a dichroic dye and uniaxially stretching it.

A polarizer obtained by dying a polyvinyl alcohol film with iodine or a dichroic dye and uniaxially stretching can be produced by, for example, dying polyvinyl alcohol in an aqueous solution of iodine, and stretching it to 3 to 7 times its original length. If necessary, it may contain boric acid, zinc sulfate, zinc chloride or the like, or it may be immersed in an aqueous solution of potassium iodide or the like. If necessary, the polyvinyl alcohol film may be dipped in water and washed with water before dyeing. The polyvinyl alcohol film is washed with water to clean the surface of the polyvinyl alcohol film and the polyvinyl alcohol film is expanded so as to prevent unevenness such as uneven dyeing. The stretching may be carried out after dyeing with iodine or a dichroic dye, followed by stretching while dyeing, or after stretching, dyeing with iodine or a dichroic dye. It can be stretched in an aqueous solution such as boric acid or potassium iodide or in a water bath.

The polyvinyl alcohol polarizer preferably contains boric acid from the viewpoints of stretching stability and optical durability. The content of boric acid contained in the polarizer is preferably 25% by weight or less, more preferably 20% by weight or less, further preferably 18% by weight or less, further preferably 16% by weight or less, Or less. On the other hand, from the viewpoints of the stretching stability and optical durability of the polarizer, the content of boric acid with respect to the total amount of the polarizer is preferably 10% by weight or more, more preferably 12% by weight or more.

In the present invention, a polyvinyl alcohol polarizer having a thickness of 10 mu m or less is used. When the thickness of the polyvinyl alcohol polarizer exceeds 10 탆, it is difficult to obtain sufficient flexibility. The thickness of the polarizer is preferably 8 占 퐉 or less, more preferably 7 占 퐉 or less, further preferably 6 占 퐉 or less in view of thinning and flexibility. On the other hand, the thickness of the polarizer is preferably 2 탆 or more, more preferably 3 탆 or more. Such a thin polarizer is excellent in durability against thermal shock because it has less thickness unevenness, excellent visibility, and small dimensional change.

Representative examples of the thin polarizers are disclosed in Japanese Patent No. 4751486, Japanese Patent No. 4751481, Japanese Patent No. 4815544, Japanese Patent No. 5048120, International Publication No. 2014/077599, International Publication No. 2014/077636 A thin polarizer described in a publication pamphlet or the like, or a thin polarizer obtained from the production method described in these.

^Wherein the polarizer has an optical characteristic represented by the following formula P > - (10 ^0.929 T ^-42.4 -1) x 100 (T <42.3) or P≥99.9 (Where T &gt; = 42.3). The polarizer configured to satisfy the above condition uniquely has the performance required as a liquid crystal TV display using a large display element. Specifically, it has a contrast ratio of 1000: 1 or more and a maximum luminance of 500 cd / m 2 or more. For another application, for example, the display side of the organic EL display device is bonded to the viewer side.

On the other hand, since the polarizer constituted to satisfy the above conditions exhibits a high orientation property (for example, a polyvinyl alcohol molecule) constituting the polarizer, the polarizer having a thickness of not more than 10 mu m can be used in a direction orthogonal to the absorption axis direction of the polarizer Direction) is remarkably reduced. As a result, for example, in general polarizing films, there is a very high possibility that light leakage occurs in the absorption axis direction of the polarizer. The flexible polarizing film of the present invention has excellent flexibility in spite of the use of the polyvinyl alcohol polarizer which is weak against the shock of 10 탆 or less in thickness.

As the thin polarizer, in view of being capable of stretching at a high magnification even in the process including a step of stretching in the state of a laminate and a step of dyeing, in order to improve the polarization performance, Japanese Patent No. 4751486, Japanese Patent No. 4751481 , And Japanese Patent No. 4815544. In particular, it is preferable to use a boric acid aqueous solution described in Japanese Patent No. 4751481 and Japanese Patent No. 4815544 And a step of auxiliary drawing publicly before stretching. These thin polarizers can be obtained by a manufacturing method including a step of stretching a polyvinyl alcohol resin (hereinafter also referred to as a PVA resin) layer and a lead resin substrate into a laminate state and a step of dyeing. With this method, even if the PVA resin layer is thin, it can be stretched without any problem such as breakage due to stretching because it is supported on the resin base material for connection.

<Reinforcing membrane>

The thickness of the reinforcing film is preferably 15 탆 or less from the viewpoint of thinning and flexibility, more preferably 10 탆 or less, further preferably 7 탆 or less. On the other hand, the thickness of the reinforcing film is preferably 1 占 퐉 or more from the viewpoints of flexibility and strength, more preferably 3 占 퐉 or more, and further preferably 5 占 퐉 or more.

The ratio (t2 / t1) of the thickness t2 of the reinforcing film to the thickness t1 of the polyvinyl alcohol polarizer is preferably 0.4 or more, more preferably 0.6 or more, and further preferably 0.8 Or more. On the other hand, the ratio (t2 / t1) is preferably 2.0 or less from the viewpoint of thinning, more preferably 1.5 or less, and further preferably 1.2 or less.

As shown in Fig. 1 (A), the reinforcing film has a higher refractive index than the first reinforcing film (b1) on one side of the polyvinyl alcohol polarizer 1, as shown in Fig. 1 (B) It is possible to more satisfactorily satisfy the flexibility in the twist test and the U-shaped stretching shrinkage test when the first reinforcing film b1 and the second reinforcing film b2 are provided on both surfaces of the polarizer 1, It is preferable in that the strength can be satisfied.

In the case where the first reinforcing film b1 and the second reinforcing film b2 are provided on both sides of the polyvinyl alcohol polarizer 1 as shown in Fig. 1 (B), the thickness of each reinforcing film may be the same The difference in thickness between the first reinforcing film b1 and the second reinforcing film b2 may be different from the thickness of the first and second reinforcing films b1 and b2 in a normal state (a state in which only the flexible polarizing film remains) and a flexibility test (various tests such as a torsion test) (Symmetrical) in the flexible polarizing film in the flexible polarizing film in the present invention, and it is preferably 10 탆 or less, more preferably 7 탆 or less, further preferably 5 탆 or less, Thickness.

It is preferable that the reinforcing membrane has a compressive modulus at 23 占 폚 of 1 MPa or more from the viewpoint of strength. The compression modulus of the reinforcing membrane is preferably 10 MPa or more, more preferably 100 MPa or more. On the other hand, when the compressive modulus of elasticity of the reinforcing film layer is too large, it tends to be too hard and the flexibility to be poor. Therefore, the compressive modulus is preferably 10 GPa or less, more preferably 1 GPa or less.

The reinforcing film can be formed from various forming materials. The reinforcing film can be formed by, for example, applying a resin material to a polyvinyl alcohol polarizer, and can be formed by depositing an inorganic oxide such as SiO ₂ on a polyvinyl alcohol polarizer by sputtering or the like. The reinforcing film is preferably a resin film formed of a resin material from the viewpoint of easy formation.

The reinforcing film may or may not be oriented, and any of them may be used. When the reinforcing film is oriented, a phase difference is generated and the optical properties of the polyvinyl alcohol polarizer are changed. Therefore, when the optical characteristics of the polarizer are maintained, it is preferable that the reinforcing film is not substantially oriented. The term "substantially not oriented" refers to a state in which the orientation of the reinforcing film is present due to the orientation of the polarizer, but the processing of positively orienting the reinforcing film is not performed. The reinforcing film which is not substantially oriented can be formed, for example, by applying a resin film forming material to a polyvinyl alcohol polarizer. On the other hand, those which are oriented as the reinforcing film can be used. The orientation of the oriented reinforcing film may be expressed as a phase difference and may be used as an optical compensation film or the like.

The material for forming the reinforcing film is not particularly limited as long as it is a material that can be brought into close contact with a polyvinyl alcohol polarizer, and examples thereof include a polyester resin, a polyether resin, a polycarbonate resin, a polyurethane resin, A polyamide-based resin, a polyimide-based resin, a PVA-based resin, an acrylic-based resin, and an epoxy-based resin. These resin materials may be used singly or in combination of two or more. Among them, at least one selected from the group consisting of a polyurethane resin, a PVA resin, an acrylic resin and an epoxy resin is preferable, and a polyurethane resin Resin, and acrylic resin are more preferable.

The reinforcing film can be formed by coating a liquid material containing a surface of the polarizer, the resin component or a curable component that can constitute the resin, and then solidifying or curing the liquid material. The form of the coating liquid as the liquid material is not particularly limited as long as it exhibits a liquid phase, and may be any of water, water dispersion, solvent, and solvent.

The forming material may contain an additive within a range that does not impair the function of the reinforcing film. For example, a silane coupling agent, a polyether compound of a polyalkylene glycol such as polypropylene glycol, a powder such as a colorant and a pigment, a dye, a surfactant, a plasticizer, a tackifier, an antistatic agent, a surface lubricant, a leveling agent, It can be suitably added in accordance with the use of an antioxidant, an antioxidant, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, an inorganic or organic filler, a metal powder, a particulate or foil. Further, a redox system to which a reducing agent is added may be employed within a controllable range.

It is advantageous that the liquid material (coating liquid) has a low viscosity. The viscosity is preferably not more than 2000 mPa · s measured at 25 ° C., more preferably not more than 1000 mPa · s, further preferably not more than 500 mPa · s, further preferably not more than 100 mPa · s.

In forming the reinforcing film, after the liquid material containing the resin component is coated, the resin component is solidified according to the kind. The liquid material containing the resin component is a solution or dispersion in which the resin component is dissolved in a solvent and is used, for example, as a solution in an aqueous system, a dispersion in an aqueous dispersion system, or a solution in a solvent system. The solidification refers to the formation of a resin layer by removing the solvent from the liquid material.

As the dispersion liquid of the water dispersion system, an aqueous resin emulsion can be used. The aqueous resin emulsion contains emulsion resin particles emulsified in water (dispersion medium). The reinforcing membrane of the present invention can be formed by directly applying a forming material containing the water-based resin emulsion to a polarizer and drying it.

The resin constituting the emulsion resin is not particularly limited, and examples thereof include an acrylic resin, a silicone resin, a polyurethane resin, and a fluorine resin. Of these, a polyurethane resin and an acrylic resin are preferable in the present invention in view of excellent optical transparency and excellent weather resistance and heat resistance.

Examples of the water-based resin emulsion include trade name: SE-2915E (acrylic emulsion containing UV absorber) manufactured by TAISEI PINE CHEMICAL Co., Ltd., ARON A-104 and ARON A-106 manufactured by Toagosei Co., have.

On the other hand, in the formation of the transparent resin layer, after the liquid material containing the curable component capable of constituting the resin is coated, curing is performed so that the curable component can form the resin according to the type of the curable component . The liquid material containing the curable component capable of constituting the resin can be used as a solventless system if the curable component is a liquid. The liquid material may be a solution in which the curable component is dissolved in a solvent. Further, even when the curable component is a liquid, it can be used as a solution. The solvent may be appropriately selected depending on the curing component used. For example, when an acrylic monomer forming an acrylic resin is used as the curable component and an epoxy monomer forming an epoxy resin is used, active energy ray irradiation (ultraviolet irradiation) is applied to the liquid material containing the curable component, And the like.

A curing-type forming material containing a curable component capable of constituting a resin with respect to the reinforcing film will be described. The curable component can be largely classified into an active energy ray-curable type such as an electron beam curable type, an ultraviolet ray curable type, and a visible ray curable type and a thermosetting type. The ultraviolet curable type and visible light curable type can be classified into a radical polymerization curing type and a cationic polymerization curing type. In the present invention, an active energy ray in a wavelength range of 10 nm to less than 380 nm is referred to as an ultraviolet ray, and an active energy ray in a wavelength range of 380 nm to 800 nm is referred to as a visible ray. The radically polymerizable curable component can be used as a thermosetting curable component.

&Quot; Radical polymerization curing type forming material &quot;

As the curable component, for example, a radical polymerizable compound can be given. The radical polymerizing compound includes a compound having a radically polymerizable functional group of a carbon-carbon double bond such as a (meth) acryloyl group or a vinyl group. These curable components may be any of monofunctional radically polymerizable compounds or bifunctional or higher functional polyfunctional radically polymerizable compounds. These radically polymerizable compounds may be used alone or in combination of two or more. As the radically polymerizable compound, for example, a compound having a (meth) acryloyl group is preferable. In the present invention, (meth) acryloyl means an acryloyl group and / or a methacryloyl group, and " (meth) "

&Quot; Monofunctional Radical Polymerizable Compound &

Examples of the monofunctional radically polymerizable compound include (meth) acrylamide derivatives having a (meth) acrylamide group. (Meth) acrylamide derivatives are preferable because they ensure adhesion with a polarizer and also have a high polymerization rate and excellent productivity. Specific examples of the (meth) acrylamide derivatives include N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl Alkyl (meth) acrylamide derivatives such as N-butyl (meth) acrylamide, N-butyl (meth) acrylamide and N-hexyl (Meth) acrylamide derivatives containing N-hydroxyalkyl groups such as N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide and N-methylol-N-propane (meth) acrylamide; (Meth) acrylamide derivatives containing N-aminoalkyl groups such as aminomethyl (meth) acrylamide and aminoethyl (meth) acrylamide; N-alkoxy group-containing (meth) acrylamide derivatives such as N-methoxymethyl acrylamide and N-ethoxymethylacrylamide; (Meth) acrylamide derivatives containing N-mercaptoalkyl groups such as mercaptomethyl (meth) acrylamide and mercaptoethyl (meth) acrylamide; And the like. Examples of the heterocyclic ring-containing (meth) acrylamide derivative in which the nitrogen atom of the (meth) acrylamide group forms a heterocycle include N-acryloylmorpholine, N-acryloylpiperidine, N- Acryloylpyridine, N-acryloylpyrrolidine, and the like.

Among the above (meth) acrylamide derivatives, N-hydroxyalkyl group-containing (meth) acrylamide derivatives are preferable from the viewpoint of adhesion with a polarizer, and N-hydroxyethyl (meth) acrylamide is particularly preferable.

Examples of the monofunctional radically polymerizable compound include various (meth) acrylic acid derivatives having a (meth) acryloyloxy group. Specific examples include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) (Meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl Acrylate, n-hexyl (meth) acrylate, cetyl (meth) acrylate, n-octyl (meth) acrylate, (Meth) acrylic acid (1 to 20 carbon atoms) alkyl esters such as 2-ethylhexyl (meth) acrylate, 4-methyl-2-propylpentyl (meth) acrylate and n-octadecyl .

Examples of the (meth) acrylic acid derivatives include cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate and cyclopentyl (meth) acrylate;

Aralkyl (meth) acrylates such as benzyl (meth) acrylate;

2-norbornylmethyl (meth) acrylate, 2-norbornylmethyl (meth) acrylate, 5-norbornen- Polycyclic (meth) acrylates such as dicyclopentenyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate and dicyclopentanyl (meth) acrylate;

(Meth) acrylates such as 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- methoxymethoxyethyl (Meth) acrylate, phenoxyethyl (meth) acrylate, alkylphenoxypolyethylene glycol (meth) acrylate, or phenoxy group-containing (meth) acrylate; And the like.

Examples of the (meth) acrylic acid derivatives include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (Meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxyoctyl (meth) acrylate, (Meth) acrylate such as hydroxyaryl (meth) acrylate, hydroxyaryl (meth) acrylate, and hydroxyaryl (meth) Hydroxy-3-phenoxypropyl (meth) acrylate, and other hydroxyl group-containing (meth) acrylates;

(Meth) acrylates such as glycidyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate glycidyl ether;

2,2,2-trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl (meth) acrylate, Halogen-containing (meth) acrylates such as acrylate, octafluoropentyl (meth) acrylate, heptadecafluorodecyl (meth) acrylate and 3-chloro-2-hydroxypropyl (meth) acrylate;

Alkylaminoalkyl (meth) acrylates such as dimethylaminoethyl (meth) acrylate;

(Meth) acrylate, 3-methyl-oxetanylmethyl (meth) acrylate, 3-methyl-oxetanylmethyl (Meth) acrylate, 3-hexyl-oxetanylmethyl (meth) acrylate and other oxetane group-containing (meth) acrylates;

(Meth) acrylate having a heterocyclic ring such as tetrahydrofurfuryl (meth) acrylate or butyrolactone (meth) acrylate, neopentyl glycol di (meth) acrylate adduct of hydroxypivalic acid, p-phenylphenol Methacrylate, and the like.

Examples of the monofunctional radically polymerizable compound include carboxyl group-containing monomers such as (meth) acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid and isocrotonic acid.

Examples of the monofunctional radically polymerizable compound include lactam-based vinyl monomers such as N-vinylpyrrolidone, N-vinyl-epsilon -caprolactam and methylvinylpyrrolidone; Vinyl-based monomers having a nitrogen-containing heterocyclic ring such as vinylpyridine, vinylpiperidine, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole and vinylmorpholine .

As the monofunctional radical polymerizable compound, a radical polymerizable compound having an active methylene group can be used. The radical polymerizable compound having an active methylene group is a compound having an active double bond group such as a (meth) acryl group at the terminal or in the molecule, and having an active methylene group. Examples of the active methylene group include an acetoacetyl group, an alkoxymonyl group, and a cyanoacetyl group. The active methylene group is preferably an acetoacetyl group. Specific examples of the radically polymerizable compound having an active methylene group include 2-acetoacetoxyethyl (meth) acrylate, 2-acetoacetoxypropyl (meth) acrylate, 2-acetoacetoxy- Acetoacetoxyalkyl (meth) acrylates such as methacrylate; 2-cyanoacetoxyethyl (meth) acrylate, N- (2-cyanoacetoxyethyl) acrylamide, N- (2-propionylacetoxy Butyl) acrylamide, N- (4-acetoacetoxymethylbenzyl) acrylamide, N- (2-acetoacetylaminoethyl) acrylamide and the like. The radically polymerizable compound having an active methylene group is preferably acetoacetoxyalkyl (meth) acrylate.

&Quot; Polyfunctional Radical Polymerizable Compound &quot;

Examples of the bifunctional or more polyfunctional radically polymerizable compound include tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) (Meth) acrylate, bisphenol A di (meth) acrylate, bisphenol A di (meth) acrylate, 1,10-decanediol diacrylate, (Meth) acrylate, neopentyl glycol di (meth) acrylate, tricyclodecane (meth) acrylate, bisphenol A diglycidyl ether di (Meth) acrylate, dimethanol di (meth) acrylate, cyclic trimethylol propane formal (meth) acrylate, dioxane glycol di (meth) acrylate, trimethylol propane tri Acrylates such as pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and EO modified diglycerin tetra (meth) ) Esters of acrylic acid and polyhydric alcohols, and 9,9-bis [4- (2- (meth) acryloyloxyethoxy) phenyl] fluorene. Specific examples thereof include Aronix M-220, M-306 (manufactured by Toagosei Co., Ltd.), light acrylate 1,9ND-A (manufactured by Kyowa Chemical Industry Co., Ltd.), light acrylate DGE- DCP-A (manufactured by Kyowa Chemical Industry Co., Ltd.), SR-531 (manufactured by Sartomer Company), and CD-536 (manufactured by Sartomer Company). Further, if necessary, various epoxy (meth) acrylates, urethane (meth) acrylates, polyester (meth) acrylates and various (meth) acrylate monomers may be cited.

The radical polymerizing compound is preferably used in combination with the monofunctional radically polymerizable compound and the polyfunctional radically polymerizable compound from the viewpoint of achieving compatibility with the polarizer and optical durability. It is usually preferable to use the compound in a proportion of 3 to 80% by weight of the monofunctional radically polymerizable compound and 20 to 97% by weight of the polyfunctional radically polymerizable compound per 100% by weight of the radically polymerizable compound.

&Lt; Modes of radical polymerization curing type forming material &

The radical polymerization-curing forming material can be used as an active energy radiation curing type or a thermosetting type forming material. When an electron beam or the like is used for an active energy ray, the active energy ray-curable former need not contain a photopolymerization initiator. However, when ultraviolet rays or visible rays are used for an active energy ray, it is preferable to contain a photopolymerization initiator. On the other hand, when the curable component is used as a thermosetting component, the formation material preferably contains a thermal polymerization initiator.

&Quot; Photopolymerization initiator &

The photopolymerization initiator in the case of using a radical polymerizable compound is appropriately selected by an active energy ray. In the case of curing by ultraviolet light or visible light, a photopolymerization initiator of ultraviolet or visible light cleavage is used. Examples of the photopolymerization initiator include benzophenone compounds such as benzyl, benzophenone, benzoylbenzoic acid and 3,3'-dimethyl-4-methoxybenzophenone; (2-hydroxy-2-propyl) ketone,? -Hydroxy- ?,? '- dimethylacetophenone, 2-methyl-2-hydroxypropiophenone,? Aromatic ketone compounds such as hydroxycyclohexyl phenyl ketone; Methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1- [4- (methylthio) -1; Benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, and anisoin methyl ether; Aromatic ketal compounds such as benzyl dimethyl ketal; Aromatic sulfonyl chloride-based compounds such as 2-naphthalenesulfonyl chloride; A photoactive oxime-based compound such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime; Thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4- Thioxanthone compounds such as santone, 2,4-diisopropylthioxanthone and dodecylthioxanthone; Camphorquinone; Halogenated ketones; Acylphosphine oxides; Acylphosphonates, and the like.

The blending amount of the photopolymerization initiator is 20 parts by weight or less based on 100 parts by weight of the total amount of the curable component (radical polymerizable compound). The blending amount of the photopolymerization initiator is preferably 0.01 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, further preferably 0.1 to 5 parts by weight.

When the curable-type forming material is used as a curable component in a visible light curable type containing a radically polymerizable compound, it is particularly preferable to use a photopolymerization initiator having a high sensitivity to light of 380 nm or more. A photopolymerization initiator having high sensitivity to light of 380 nm or more will be described later.

Examples of the photopolymerization initiator include compounds represented by the following formula (1);

[Chemical Formula (1)

( ^{1) wherein} R ¹ and R ² are the same as or different from each other, or R ¹ and R ² are independently -H, -CH ₂ CH ₃ , -iPr or Cl, Is preferably used in combination with a photopolymerization initiator having high sensitivity to a light having a wavelength of 380 nm or more, which will be described later. When the compound represented by the formula (1) is used, the adhesion is excellent as compared with the case where a photopolymerization initiator having high sensitivity to light of 380 nm or more is used alone. Among the compounds represented by the formula (1), diethyl thioxanthone in which R ¹ and R ² are -CH ₂ CH ₃ is particularly preferable. The composition ratio of the compound represented by the formula (1) in the forming agent is preferably 0.1 to 5 parts by weight, more preferably 0.5 to 4 parts by weight, and more preferably 0.9 to 3 parts by weight based on 100 parts by weight of the total amount of the curable component It is more desirable to be negative.

It is also preferable to add a polymerization initiator if necessary. Examples of the polymerization initiator include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, , And ethyl 4-dimethylaminobenzoate is particularly preferable. When the polymerization initiator is used, the addition amount is usually 0 to 5 parts by weight, preferably 0 to 4 parts by weight, and most preferably 0 to 3 parts by weight based on 100 parts by weight of the total amount of the curable component.

If necessary, known photopolymerization initiators can be used in combination. As the photopolymerization initiator, it is preferable to use a photopolymerization initiator having high sensitivity to light of 380 nm or longer. Specific examples thereof include 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one, 2-benzyl- -1,2- (dimethylamino) -2 - [(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1- butanone, 2,4,6- Diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (? 5-2,4-cyclopentadien-1-yl) (1H-pyrrol-1-yl) -phenyl) titanium, and the like.

Particularly, in addition to the photopolymerization initiator of the formula (1) as a photopolymerization initiator, a compound further represented by the following formula (2);

(2)

(Wherein, R ^3, R ⁴ and R ⁵ are _{-H, -CH 3, -CH 2 CH} 3, or -iPr represents Cl, R ^3, R ⁴ and R ⁵ are the same or different) a Is preferably used. Methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one (trade name: IRGACURE907, manufactured by BASF), which is also a commercially available product, is preferably used as the compound represented by the formula (2) It is possible. 2-dimethylamino-2 - [(4-fluorophenyl) ethanone] -1- (trade name: IRGACURE369, Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone (trade name: IRGACURE379, manufactured by BASF).

<Radical Polymerization Compound Having Active Methylene Group and Radical Polymerization Initiator Having Hydrogen Abstraction>

When a radically polymerizable compound having an active methylene group is used as the radical polymerizable compound in the active energy ray curable type forming material, it is preferable to use it in combination with a radical polymerization initiator having hydrogen drawing action.

Examples of the radical polymerization initiator having a hydrogen drawing action include a thioxanthone radical polymerization initiator and a benzophenone radical polymerization initiator. The radical polymerization initiator is preferably a thioxanthone radical polymerization initiator. Examples of the thioxanthone radical polymerization initiator include the compounds represented by the above formula (1). Specific examples of the compound represented by the formula (1) include thioxanthone, dimethylthioxanthone, diethylthioxanthone, isopropylthioxanthone and chlorothioxanthone. Among the compounds represented by the formula (1), diethyl thioxanthone in which R ¹ and R ² are -CH ₂ CH ₃ is particularly preferable.

When the radical polymerization initiator having an active methylene group and a radical polymerization initiator having a hydrogen drawing action is contained in the active energy ray curable type forming material, when the total amount of the curing component is 100 wt%, the active methylene group And the radical polymerization initiator is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of the curable component.

&Quot; Thermal polymerization initiator &

As the thermal polymerization initiator, it is preferable that polymerization is not initiated by thermal cleavage when forming the reinforcing film. For example, as the thermal polymerization initiator, it is preferable that the half-life temperature for 10 hours is 65 占 폚 or higher, more preferably 75 to 90 占 폚. This half-life is an index indicating the rate of decomposition of the polymerization initiator and refers to a time until the amount of the polymerization initiator remaining in the medium becomes half. The decomposition temperature for obtaining a half-life at an arbitrary time and the half-life time at an arbitrary temperature are described in the manufacturer's catalog. For example, the &quot; Organic Peroxide Catalog Ninth Edition (May 2003) &Quot;

(10 hours half-life temperature: 64 占 폚), benzoyl peroxide (10 hours half-life temperature: 73 占 폚), 1,1-bis (t-butylperoxy) (10-hour half-life temperature: 90 占 폚), di (2-ethylhexyl) peroxydicarbonate (10 hours half life temperature: 49 占 폚), di (4-t-butylcyclohexyl) peroxydicarbonate, Tert-butyl peroxydicarbonate (10-hour half-life temperature: 51 ° C), t-butyl peroxyneodecanoate (10-hour half-life temperature: 48 ° C), t- (10 hours half-life temperature: 64 占 폚), di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Half-life temperature: 66 占 폚), di (4-methylbenzoyl) peroxide, dibenzoyl peroxide (10 hours half life temperature: 73 占 폚), t-butyl peroxyisobutyrate ), There may be mentioned organic peroxides such as 1,1-di (t--hexylperoxy) cyclohexane.

Examples of the thermal polymerization initiator include 2,2'-azobisisobutyronitrile (10-hour half-life temperature: 67 ° C), 2,2'-azobis (2-methylbutyronitrile) Temperature: 67 占 폚) and 1,1-azobis-cyclohexane-1-carbonitrile (10 hour half-life temperature: 87 占 폚).

The blending amount of the thermal polymerization initiator is 0.01 to 20 parts by weight based on 100 parts by weight of the total amount of the curable component (radically polymerizable compound). The blending amount of the thermal polymerization initiator is further preferably 0.05 to 10 parts by weight, more preferably 0.1 to 3 parts by weight.

&Quot; Cationic polymerization curing type forming material &quot;

As the curing component of the cationic polymerization curing type forming material, a compound having an epoxy group or an oxetanyl group can be mentioned. The compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used. As the preferable epoxy compound, a compound (aromatic epoxy compound) having at least two epoxy groups and at least one aromatic ring in the molecule, at least two epoxy groups in the molecule and at least one of which is an adjacent 2 (Alicyclic epoxy compound) formed between two carbon atoms.

&Quot; Photocation polymerization initiator &quot;

The cationic polymerization curing agent includes a cationic photopolymerization initiator in that it contains the epoxy compound and the oxetane compound described above as a curable component and they are all cured by cationic polymerization. This photo cationic polymerization initiator generates a cationic species or a Lewis acid by irradiation of an active energy ray such as visible light, ultraviolet ray, X-ray or electron beam to initiate polymerization reaction of an epoxy group or an oxetanyl group.

<Other ingredients>

The curable-type forming material according to the present invention preferably contains the following components.

&Lt; Acrylic oligomer &

The active energy ray-curable-type forming material according to the present invention may contain an acrylic oligomer obtained by polymerizing (meth) acrylic monomer in addition to the curable component relating to the radical polymerizing compound. By containing the acrylic oligomer in the active energy ray curable type forming material, the curing shrinkage upon irradiation and curing of the active energy ray to the reinforcing film can be reduced, and the interfacial stress between the reinforcing film and the polarizer can be reduced. In order to sufficiently suppress the curing shrinkage, the content of the acrylic oligomer is preferably 20 parts by weight or less, more preferably 15 parts by weight or less, based on 100 parts by weight of the total amount of the curable component. If the content of the acrylic oligomer in the forming material is excessively large, the reaction rate at the time of irradiating the active energy ray to the forming material is severely lowered, resulting in a poor curing. On the other hand, the acrylic oligomer is preferably contained in an amount of 3 parts by weight or more based on 100 parts by weight of the total amount of the curable component, more preferably 5 parts by weight or more.

In view of workability and uniformity at the time of coating, it is preferable that the active energy ray-curable forming material has a low viscosity. Therefore, it is also preferable that the acrylic oligomer obtained by polymerization of the (meth) acrylic monomer has a low viscosity. The acrylic oligomer having a low viscosity and capable of preventing curing shrinkage of the reinforcing film preferably has a weight average molecular weight (Mw) of 15,000 or less, more preferably 10,000 or less, and particularly preferably 5,000 or less. On the other hand, in order to sufficiently suppress the curing shrinkage of the reinforcing film, the weight average molecular weight (Mw) of the acrylic oligomer is preferably 500 or more, more preferably 1,000 or more, and particularly preferably 1,500 or more. Specific examples of the (meth) acrylic monomer constituting the acrylic oligomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) (Meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, (Meth) acrylate, n-hexyl (meth) acrylate, cetyl (meth) acrylate, (Meth) acrylic acid such as n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 4-methyl- (Carbon number 1-20) alkyl esters, and also, for example, cycloalkyl (meth) acrylic acid (Meth) acrylate, cyclohexyl (meth) acrylate and cyclopentyl (meth) acrylate), aralkyl (meth) acrylates (Meth) acrylate, 2-norbornylmethyl (meth) acrylate, 5-norbornen-2-yl-methyl Methyl (meth) acrylate, etc.), hydroxyl group-containing (meth) acrylate esters such as hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (Meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, Acrylate, methoxymethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethylcarbamate (Meth) acrylate, epoxy group-containing (meth) acrylate (e.g., glycidyl (meth) acrylate), halogen-containing (meth) (Meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoro (Meth) acrylate such as propyl (meth) acrylate, octafluoropentyl (meth) acrylate, heptadecafluorodecyl (meth) Etc.). These (meth) acrylates may be used alone or in combination of two or more. Specific examples of the acrylic oligomer include "ARUFON" manufactured by Toagosei Co., Ltd., "Actflow" manufactured by Soken Chemical Industries, Ltd., and "JONCRYL" manufactured by BASF Japan Co.,

&Lt; Mineral acid (photo acid) generator >

The active energy ray-curable-type forming material may contain a photo-acid generator. When the active energy ray-curable-type forming material contains a photoacid generator, the water resistance and durability of the reinforcing film can be remarkably improved as compared with the case where the photoacid generator is not contained. The photoacid generator may be represented by the following formula (3)

(3)

L ⁺ X ^-

(Wherein L ⁺ represents an arbitrary onium cation, and X ^- represents PF ₆ ^- , SbF ₆ ^- , AsF ₆ ^- , SbCl ₆ ^- , BiCl ₅ ^- , SnCl ₆ ^- , ClO ₄ ^- , dithiocarbamate Anion, SCN &lt; ^- &gt;).

Examples of preferred onium salts constituting the photoacid generator are selected from PF ₆ ^- , SbF ₆ ^- , AsF ₆ ^- , SbCl ₆ ^- , BiCl ₅ ^- , SnCl ₆ ^- , ClO ₄ ^- , dithiocarbamate anions, SCN ^- It is an onium salt composed of an anion.

Concretely, "SAIRACURE UVI-6992", "SAIRACURE UVI-6974" (manufactured by Dow Chemical Co., Ltd.), "Adeka Optoma-SP150", "Adeka Optoma-SP152" CI-2855 &quot; (manufactured by Nippon Soda Co., Ltd.) and &quot; IRGACURE250 &quot; (manufactured by Ciba Specialty Chemicals) (Available from Sanxing Chemical Co., Ltd.), &quot; CPI-100L &quot;, &quot; SANEID SI-80L &quot;, &quot; SANEID SI- WPI-041 "," WPI-044 "," WPI-100 "," CPI-100A "(manufactured by SANA PRO) 054 "," WPI-055 "," WPAG-281 "," WPAG-567 "and" WPAG-596 "(all manufactured by Wako Pure Chemical Industries, Ltd.) are preferable specific examples of the photoacid generator.

The content of the photoacid generator is preferably 10 parts by weight or less, preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, particularly preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the total amount of the curable component .

The formation of the reinforcing film by the curing type forming material is carried out by coating the surface of the polarizer with a curing type forming material and thereafter curing.

The polarizer may perform the surface modification treatment before coating the curing-type forming material. Specific examples of the treatment include corona treatment, plasma treatment, and saponification treatment.

The coating method of the curing-type forming material is appropriately selected in accordance with the viscosity of the curing-type forming material or the intended thickness. Examples of the coating method include a reverse coater, a gravure coater (direct, reverse or offset), a bar reverse coater, a roll coater, a die coater, a bar coater and a rod coater. In addition, a dipping method or the like can be appropriately used for coating.

&Lt; Curing of forming material &

The curing-type forming material is used as an active energy ray curing type forming material or a thermosetting type forming material. The active energy ray curable type forming material can be used as an electron beam curable type, an ultraviolet ray curable type, or a visible light curable type.

«Active energy ray curing type»

In the active energy ray-curable forming material, a polarizing element is coated with an active energy ray-curable forming material, and then an active energy ray (electron beam, ultraviolet ray, visible ray, etc.) is irradiated and the active energy ray curing type forming material is cured to form a reinforcing film. The irradiation direction of the active energy ray (electron beam, ultraviolet ray, visible ray, etc.) can be irradiated in any appropriate direction. Preferably, irradiation is performed on the side of the reinforcing membrane.

&Quot; Electron beam hardening type &

In the electron beam hardening type, the irradiation condition of the electron beam may be any appropriate condition as far as it is capable of curing the active energy ray hardening type forming material. For example, in the electron beam irradiation, the acceleration voltage is preferably 5 kV to 300 kV, and more preferably 10 kV to 250 kV. When the accelerating voltage is less than 5 kV, the electron beam does not reach the deepest portion of the reinforcing film, which may cause insufficient curing. If the accelerating voltage exceeds 300 kV, the penetrating power passing through the sample is too strong, . The irradiation dose (irradiation dose) is 5 to 100 kGy, more preferably 10 to 75 kGy. If the irradiation dose is less than 5 kGy, the adhesive becomes insufficient in curing. If the irradiation dose exceeds 100 kGy, the polarizer is damaged, resulting in a decrease in mechanical strength and yellowing, so that desired optical characteristics can not be obtained.

The irradiation with the electron beam is usually carried out in an inert gas, but may be carried out under a condition in which air or oxygen is slightly introduced, if necessary.

«UV curing type, visible light curing type»

As the active energy ray, it is preferable to use a visible ray having a wavelength range of 380 nm to 450 nm, in particular, an active energy ray having the largest irradiation amount of visible ray having a wavelength range of 380 nm to 450 nm. As the active energy ray, a gallium-encapsulated metal halide lamp and an LED light source emitting light in a wavelength range of 380 to 440 nm are preferable. Or ultraviolet rays and visible light such as low pressure mercury lamps, medium pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, incandescent lamps, xenon lamps, halogen lamps, carbon arc lamps, metal halide lamps, fluorescent lamps, tungsten lamps, gallium lamps, excimer lasers, May be used, and ultraviolet rays of a shorter wavelength than 380 nm may be shielded by using a band pass filter.

«Heat curing type»

On the other hand, the thermosetting type forming material is applied to a polarizer and then heated to initiate polymerization with a thermal polymerization initiator to form a cured layer (reinforcing film). The heating temperature is set according to the thermal polymerization initiator, but it is about 60 to 200 占 폚, preferably 80 to 150 占 폚.

As the material for forming the reinforcing film, for example, a cyanoacrylate-based forming material, an epoxy based forming material, or an isocyanate-based forming material can be used.

Examples of the cyanoacrylate-based forming material include alkyl-? -Cyanoacrylates such as methyl-? -Cyanoacrylate, ethyl? -Cyanoacrylate, butyl? -Cyanoacrylate and octyl-? -Cyanoacrylate ? -cyanoacrylate, cyclohexyl-? -cyanoacrylate, methoxy-? -cyanoacrylate, and the like. As the cyanoacrylate-based forming agent, for example, those used as cyanoacrylate-based adhesives can be used.

The epoxy-based forming material may be used singly as an epoxy resin, or may contain an epoxy curing agent. When an epoxy resin is used as a single unit, a photopolymerization initiator is added and cured by irradiation with active energy rays. When an epoxy curing agent is added as the epoxy-based forming material, for example, those used as an epoxy-based adhesive can be used. The mode of use of the epoxy-based forming material may be used as a one-pack type containing an epoxy resin and a curing agent thereof, but may be used as a two-pack type in which a curing agent is mixed with an epoxy resin. The epoxy-based forming material is usually used as a solution. The solution may be a solvent system, or may be a water system such as an emulsion, a colloidal dispersion, or an aqueous solution.

Examples of the epoxy resin include various compounds containing two or more epoxy groups in the molecule, and examples thereof include bisphenol type epoxy resins, aliphatic epoxy resins, aromatic epoxy resins, halogenated bisphenol type epoxy resins, biphenyl type epoxy resins And the like. The epoxy resin can be appropriately determined in accordance with the epoxy equivalent and the number of functional groups, but from the viewpoint of durability, an epoxy equivalent of 500 or less is preferably used.

The curing agent of the epoxy resin is not particularly limited, and various phenol resin-based, acid anhydride-based, carboxylic acid-based, and polyamine-based ones can be used. As the phenol resin-based curing agent, for example, phenol novolak resin, bisphenol novolac resin, xylylene phenol resin, cresol novolak resin, and the like are used. Examples of the acid anhydride-based curing agent include: Maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and succinic anhydride, and examples of the carboxylic acid-based curing agent include block carboxylic acids in which carboxylic acids such as pyromellitic acid and trimellitic acid and vinyl ether are added have. As the epoxy-based two-liquid forming material, for example, two liquids of an epoxy resin and a polythiol, two liquids of an epoxy resin and a polyamide, and the like can be used.

The blending amount of the curing agent is preferably 30 to 70 parts by weight, more preferably 40 to 60 parts by weight, based on 100 parts by weight of the epoxy resin, though it varies depending on the equivalent amount to the epoxy resin.

In addition to the epoxy resin and its curing agent, various curing accelerators may be used for the epoxy-based forming agent. Examples of the curing accelerator include various imidazole-based compounds and derivatives thereof, and dicyandiamide.

Examples of the isocyanate-based forming material include those used as a crosslinking agent in the formation of a pressure-sensitive adhesive layer. As the isocyanate-based crosslinking agent, a compound having at least two isocyanate groups can be used. For example, the polyisocyanate compound may be used as an isocyanate-based forming agent. Specific examples thereof include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, 1,3-bisisocyanatomethyl cyclohexane, hexamethylene diisocyanate, tetramethyl xylylene diisocyanate, m- Dimeric benzyl isocyanate, methylene bis 4-phenylisocyanate, p-phenylenediisocyanate, trimer thereof such as isomers thereof or isocyanurate tris (6-isocyanate hexyl) and polyhydric alcohols such as biuret or trimethylolpropane or polyhydric amines. As the isocyanate-based crosslinking agent, it is preferable to have three or more isocyanate groups such as isocyanurate tris (6-isocyanate hexyl). Examples of the isocyanate-based forming material include those used as isocyanate-based adhesives.

Among the isocyanate-based forming materials, in the present invention, it is preferable to use a material having a rigid structure in which the ratio of the cyclic structure (benzene ring, cyanurate ring, isocyanurate ring, etc.) in the molecular structure is large in the structure. As the isocyanate-based forming material, for example, trimethylolpropane-tri-tolylene isocyanate, tris (hexamethylene isocyanate) isocyanurate and the like are preferably used.

The isocyanate-based crosslinking agent may be one obtained by adding a protecting group to a terminal isocyanate group. Examples of protecting groups include oxime and lactam. When the isocyanate group is protected, the isocyanate group is reacted by dissociating the protecting group from the isocyanate group by heating.

Further, a reaction catalyst may be used to increase the reactivity of the isocyanate group. The reaction catalyst is not particularly limited, but a tin catalyst or an amine catalyst is preferred. The reaction catalyst may be used alone or in combination of two or more. The amount of the reaction catalyst used is usually 5 parts by weight or less based on 100 parts by weight of the isocyanate-based crosslinking agent. When the amount of the reaction catalyst is large, the crosslinking reaction rate is accelerated and foaming of the forming material occurs. Sufficient adhesion can not be obtained even by using a forming material after foaming. Generally, when a reaction catalyst is used, the amount is preferably 0.01 to 5 parts by weight, more preferably 0.05 to 4 parts by weight.

As the tin catalyst, any of inorganic or organic catalysts can be used, but organic catalysts are preferable. The inorganic tin-based catalyst includes, for example, stannous chloride, stannic chloride, and the like. The organic tin-based catalyst preferably has at least one organic group such as an aliphatic group having a skeleton such as a methyl group, an ethyl group, an ether group or an ester group, or an alicyclic group. For example, tetra-n-butyltin, tri-n-butyltin acetate, n-butyltin trichloride, trimethyltin hydroxide, dimethyltin dichloride, dibutyltin dilaurate and the like.

The amine-based catalyst is not particularly limited. For example, at least one organic group such as an alicyclic group such as quinuclidine, amidine, and diazabicyclo-undecene. Other examples of the amine catalysts include triethylamine and the like. As reaction catalysts other than the above, cobalt naphthenate, benzyltrimethylammonium hydroxide and the like can be exemplified.

The isocyanate-based forming material is usually used as a solution. The solution may be a solvent system, or may be a water system such as an emulsion, a colloidal dispersion, or an aqueous solution. The organic solvent is not particularly limited as long as the components constituting the forming material are uniformly dissolved. As the organic solvent, for example, toluene, methyl ethyl ketone, ethyl acetate and the like can be given. Also in the case of the aqueous system, for example, alcohols such as n-butyl alcohol and isopropyl alcohol, and ketones such as acetone may be blended. In the case of an aqueous system, a dispersant may be used, or a functional group having a low reactivity with an isocyanate group such as a carboxylic acid salt, a sulfonic acid salt or a quaternary ammonium salt, or a water-dispersible component such as polyethylene glycol may be added to an isocyanate-based crosslinking agent.

The formation (curing) of a reinforcing film by a cyanoacrylate-based forming material, an epoxy based forming material or an isocyanate based forming material can be appropriately selected depending on the kind of the above-mentioned forming material, but is usually about 30 to 100 DEG C, By drying at 50 to 80 DEG C for 0.5 to 15 minutes. In addition, in the case of the cyanoacrylate-based forming material, since the curing is rapid, the reinforcing film can be formed in a shorter time than the above-mentioned time.

As a material for forming the reinforcing film, polyurethane can be used. The polyurethane is preferably a reaction product of a high molecular weight polyol compound and / or a low molecular weight polyol and an isocyanate compound. Further, in addition to the high molecular weight polyol compound and the isocyanate compound, the polyurethane may be further reacted with a low molecular weight polyamino compound and / or polyol compound as a chain extender.

The polymer polyol compound preferably has a weight average molecular weight of 100 to 4,000 and has two or more hydroxyl groups in one molecule, and a polyether polyol, a polyester polyol, a polycarbonate polyol, or the like is used. The polymer polyol compound preferably has a weight average molecular weight of 500 to 4,000, more preferably 600 to 3,500, and further preferably 1,000 to 3,000.

Examples of the polyether polyol include an aliphatic polyether polyol and an aromatic polyether polyol. More specifically, it is possible to use a low-molecular polyol such as a trihydric alcohol such as ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol and the like, and trihydric alcohol such as trimethylolpropane, glycerin and pentaerythritol Polyether obtained by addition polymerization of ethylene oxide, propylene oxide, tetrahydrofuran and the like is used. These may be used alone or in combination of two or more.

Examples of the polyester polyol include an aliphatic polyester polyol and an aromatic polyester polyol. More specifically, it is possible to use an alcohol such as the above-mentioned dihydric alcohol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol and the like and a dibasic acid such as adipic acid, azelaic acid, A polyester made of a polycondensate is used. These may be used alone, or two or more kinds may be mixed and used.

Also, there may be mentioned polybutadiene-based polyols such as polybutadiene, butadiene-acrylonitrile copolymer and polyisoprene having hydroxyl groups at both ends of the molecule, polybutadiene hydrate having a hydroxyl group at both ends of the molecule, Isophthalic anhydride and polyolefin-based polyols such as polyisobutylene, and the like.

Examples of the polyamino compound used as the chain extender include an aliphatic polyamino compound and an aromatic polyamino compound. More specifically, there may be mentioned, for example, ethylenediamine, 3,3'-dichloro-4,4'-diaminodiphenylmethane (MOCA), diethyltoluenediamine (DETDA), 4,4'- Butyl) diphenylmethane, 2,4-tolylene diamine, 2,6-tolylene diamine, xylylenediamine, hexanediamine, isophoronediamine and the like. Particularly, ethylenediamine and the like are preferable. These may be used alone, or two or more kinds may be mixed and used.

Examples of the low-molecular polyol and the polyol compound used as the chain extender include a polyether polyol and a low-molecular polyol exemplified as a polyester polyol.

The chain extender is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.5 to 7 parts by weight, and more preferably 1 to 5 parts by weight, based on 100 parts by weight of the polymer polyol compound. The durability can be improved by increasing the molecular weight sufficiently by the use of the chain extender.

The isocyanate compound is a polyisocyanate (isocyanate compound) having two or more isocyanate groups, and the same isocyanate-based forming agent can be used. The isocyanate compound may also be used as a urethane prepolymer obtained by previously reacting the low-molecular polyol exemplified in the polyester polyol with the above-exemplified isocyanate compound.

In order to react the isocyanate group of the polyisocyanate with the hydroxyl group, it is preferable to use dibutyltin dilaurate, stannous octoate, 1,4-diazabicyclo (2,2,2) octane or the like as a catalyst.

The formation (curing) of the reinforcing film by the polyurethane may be performed by applying a liquid material (coating liquid) of a polyurethane prepared in advance in advance to the polarizer, or the composition containing the polymer polyol compound and the isocyanate compound May be applied to the polarizer and cured to form a reinforcing film by polyurethane. The formation of the reinforcing film may be carried out usually at about 30 to 100 DEG C, preferably at 50 to 80 DEG C for about 0.5 to 15 minutes.

After the formation of the reinforcing film (curing: this is referred to as initial curing), an annealing treatment may be performed. The annealing treatment can be carried out for the purpose of promoting the reaction in the case where the isocyanate does not react sufficiently after the initial curing (the state in which the reactor remains in the reinforcing film) in the isocyanate-based forming material, the polyurethane based forming material and the like. The annealing treatment can be performed in any of the drying conditions or the humidifying conditions. The annealing treatment temperature is about 30 to 100 DEG C, preferably 50 to 80 DEG C, similar to the conditions at the time of the initial curing. There is no particular restriction on the annealing time.

The weight average molecular weight of the polyurethane is preferably from 30,000 to 200,000, more preferably from 4,000 to 150,000, and even more preferably from 50,000 to 130,000.

(Measurement of weight average molecular weight)

The weight average molecular weight of the high molecular weight polyol compound and the polyurethane was measured by the GPC (gel permeation chromatography) method under the following conditions.

Analytical Apparatus: HLC-8120GPC manufactured by Tosoh Corporation.

Column: G7000HXL + GMHXL + GMHXL, manufactured by Tosoh Corporation.

Column size: Each 7.8mmΦ × 30cm 90cm in total.

Column temperature: 40 캜.

Flow rate: 0.8 ml / min.

Injection volume: 100 μl.

Eluent: tetrahydrofuran.

Detector: Differential refractometer.

Standard sample: polystyrene.

It is also possible to use a material having a functional group capable of forming a covalent bond with a PVA such as an isocyanate group or an epoxy group as a material for forming the reinforcing film and having a radically polymerizable functional group such as a (meth) acryloyl group or a vinyl group Compounds may be used. Examples of the compound include 2-isocyanatoethyl acrylate (trade name: CALENS AOI, manufactured by Showa Denko K.K.), 1,1- (bisacryloyloxymethyl) ethyl isocyanate (manufactured by Showa Denko KK, Lens BEI). As the above compound, a reaction product of a polymer having a diisocyanate compound as a component and a hydroxyl group-containing (meth) acrylate can be used. As such a reactant, for example, a reaction product of 2-hydroxyethyl acrylate and a polymer having a constituent component of 1,6-diisocyanatohexane (manufactured by BASF, product name: LaRoma LR9000) can be mentioned.

Since the compound has a functional group such as an isocyanate group or an epoxy group, a reinforcing film can be formed by thermal curing in the same manner as the isocyanate-based forming material and the like, and further annealing treatment can be performed. Further, since the compound has a radically polymerizable functional group, it can be used as an active energy ray-curable or thermosetting type forming material related to a radical polymerization curing-type forming material. When the compound is used as a radical polymerization curing type forming agent, other radical polymerizing compound may be used in combination with the compound.

Further, the reinforcing film may be formed from a forming material not containing a curable component, for example, from a forming material containing the polyvinyl alcohol-based resin as a main component. The polyvinyl alcohol-based resin forming the reinforcing film may be the same as or different from the polyvinyl alcohol-based resin contained in the polarizer as long as it is a &quot; polyvinyl alcohol-based resin &quot;.

Examples of the polyvinyl alcohol-based resin include polyvinyl alcohol. Polyvinyl alcohol can be obtained by saponifying polyvinyl acetate. As the polyvinyl alcohol-based resin, there can be enumerated a saponification product of a copolymer of vinyl acetate and a monomer having copolymerization. When the monomer having the copolymerization is ethylene, an ethylene-vinyl alcohol copolymer can be obtained. Examples of the monomer having the above-mentioned copolymerization include unsaturated carboxylic acids such as maleic anhydride, maleic acid, fumaric acid, crotonic acid, itaconic acid and (meth) acrylic acid and esters thereof; (Meth) allyl sulfonic acid (soda), soda sulfonate (monoalkyl maleate), disulfonic acid soda alkyl malate, N-methylol acrylamide, acrylamide alkylsulfonic acid alkali salt, N- Vinyl pyrrolidone, N-vinyl pyrrolidone derivatives, and the like. These polyvinyl alcohol resins may be used singly or in combination of two or more. Polyvinyl alcohol obtained by saponifying polyvinyl acetate is preferable from the viewpoint of controlling the heat of crystal fusion of the reinforcing film to 30 mJ / mg or more and satisfying the moisture resistance and water resistance.

The degree of saponification of the polyvinyl alcohol-based resin may be 95% or more, for example. From the standpoint of satisfying the heat and humidity resistance and water resistance by controlling the crystal melting heat quantity of the reinforcing film to 30 mJ / mg or more, Or more, more preferably 99.7% or more. The degree of saponification represents the ratio of units which are actually saponified with vinyl alcohol units among the units that can be converted into vinyl alcohol units by saponification, and the residues are vinyl ester units. The saponification degree can be obtained according to JIS K 6726-1994.

The average degree of polymerization of the polyvinyl alcohol-based resin may be 500 or more, for example, but the average degree of polymerization is preferably 1,000 or more from the viewpoint of satisfying the heat and humidity resistance and water resistance by controlling the crystal melting heat quantity of the reinforcing film to 30 mJ / More preferably 1,500 or more, further preferably 2,000 or more. The average polymerization degree of the polyvinyl alcohol-based resin is measured according to JIS-K 6726.

As the polyvinyl alcohol-based resin, a modified polyvinyl alcohol-based resin having a hydrophilic functional group in the side chain of the polyvinyl alcohol or a copolymer thereof can be used. Examples of the hydrophilic functional group include an acetoacetyl group, a carbonyl group, and the like. In addition, a modified polyvinyl alcohol obtained by subjecting a polyvinyl alcohol-based resin to acetalization, urethanation, etherification, grafting, phosphoric esterification, or the like can be used.

The forming material containing the polyvinyl alcohol-based resin as a main component may contain a curing component (crosslinking agent) or the like. The proportion of the polyvinyl alcohol-based resin in the reinforcing film or the forming material (solid content) is preferably 80% by weight or more, more preferably 90% by weight or more, further preferably 95% by weight or more. However, it is preferable that the forming material does not contain a curing component (crosslinking agent) from the viewpoint of easily controlling the crystal melting heat quantity of the reinforcing film to 30 mJ / mg or more.

As the crosslinking agent, a compound having at least two functional groups having reactivity with the polyvinyl alcohol-based resin can be used. Alkylenediamines having two alkylene groups and an amino group, such as ethylenediamine, triethylenediamine and hexamethylenediamine; Tolylene diisocyanate, hydrogenated tolylene diisocyanate, trimethylolpropane tolylene diisocyanate adduct, triphenylmethane triisocyanate, methylene bis (4-phenylmethane triisocyanate, isophorone diisocyanate, and ketone oxime block or phenol block water thereof) Isocyanates such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin di or triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylol propane triglycidyl ether, diglycidyl Aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, and butylaldehyde; glyoxal, malondialdehyde, succindyaldehyde, glutaraldaldehyde, maleindialdehyde, , Dialdehydes such as phthalaldehyde, methylolurea, An amino-formaldehyde resin such as a condensed product of an alkylated methylol urea, alkylated methylol melamine, acetoguanamine, benzoguanamine and formaldehyde, such as adipic acid dihydrazide, oxalic acid dihydrazide, malonic acid di Dicarboxylic acid diesters such as hydrazide, succinic dihydrazide, glutaric acid dihydrazide, isophthalic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide and itaconic acid dihydrazide Dihydrazine, ethylene-1,2-dihydrazine, propylene-1,3-dihydrazine, and butylene-1,4-dihydrazine. Of these, amino-formaldehyde resins and water-soluble di As the amino-formaldehyde resin, a compound having a methylol group is preferable. Of these, methylolmelamine, which is a compound having a methylol group, Hi is preferred.

The curable component (cross-linking agent) may be used from the viewpoint of improving water resistance, but it is preferably 20 parts by weight or less, 10 parts by weight or less and 5 parts by weight or less based on 100 parts by weight of the polyvinyl alcohol-based resin.

The forming material is adjusted to a solution in which the polyvinyl alcohol-based resin is dissolved in a solvent. Examples of the solvent include water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide N-methylpyrrolidone, polyhydric alcohols such as various glycols and alcohols, and amines such as ethylenediamine and diethylenetriamine. . These may be used alone or in combination of two or more. Among them, it is preferable to use them as an aqueous solution using water as a solvent. The concentration of the polyvinyl alcohol-based resin in the forming material (for example, an aqueous solution) is not particularly limited, but is preferably 0.1 to 15% by weight, more preferably 0.5 to 10% by weight in view of coatability, to be.

Examples of the additive that can be incorporated into the forming material (for example, an aqueous solution) include a plasticizer and a surfactant. Examples of the plasticizer include polyhydric alcohols such as ethylene glycol and glycerin. Examples of the surfactant include nonionic surfactants.

The reinforcing film can be formed by applying the forming material to a polarizer and drying it. The application operation is not particularly limited, and any appropriate method can be employed. Various means such as a roll coating method, a spin coating method, a wire bar coating method, a dip coating method, a die coating method, a curtain coating method, a spray coating method, a knife coating method (a comma coating method and the like) .

<Surface Treatment Layer>

The surface treatment layer can be provided on one side or both sides of the flexible polarizing film of the present invention. Examples of the surface treatment layer include a hard coat layer, an anti-glare treatment layer, an anti-reflection layer, and an anti-sticking layer. The surface treatment layer is preferably a hard coat layer. As a material for forming the hard coat layer, for example, a thermoplastic resin, a material which is cured by heat or radiation can be used. Examples of the material include a radiation curable resin such as a thermosetting resin, an ultraviolet curing resin, and an electron beam curable resin. Among them, an ultraviolet curable resin which can efficiently form a cured resin layer by a simple processing operation by curing treatment by ultraviolet irradiation is preferable. Examples of the curable resin include various resins such as polyester resins, acryl resins, urethane resins, amide resins, silicon resins, epoxy resins and melamine resins, and their monomers, oligomers and polymers.

As the surface treatment layer, an antiglare layer or an antireflection layer may be provided for the purpose of improving visibility. An antiglare layer and an antireflection layer may be provided on the hard coat layer. The constituent material of the antiglare treatment layer is not particularly limited, and for example, a radiation curable resin, a thermosetting resin, a thermoplastic resin, or the like can be used. As the antireflection layer, titanium oxide, zirconium oxide, silicon oxide, magnesium fluoride and the like are used. The antireflection layer may have a plurality of layers. In addition, the surface treatment layer may be a sticking prevention layer or the like.

The thickness of the surface treatment layer can be appropriately set according to the kind of the surface treatment layer, but it is generally preferably 0.1 to 100 占 퐉. For example, the thickness of the hard coat layer is preferably 0.5 to 20 占 퐉.

<Pressure-sensitive adhesive layer>

A pressure-sensitive adhesive layer can be provided on one side or both sides of the flexible polarizing film of the present invention. A suitable pressure-sensitive adhesive may be used for forming the pressure-sensitive adhesive layer, and the kind thereof is not particularly limited. Examples of the pressure-sensitive adhesive include rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, silicone pressure-sensitive adhesives, urethane pressure-sensitive adhesives, vinyl alkyl ether pressure-sensitive adhesives, polyvinyl alcohol pressure-sensitive adhesives, polyvinylpyrrolidone pressure-sensitive adhesives, polyacrylamide pressure-sensitive adhesives and cellulosic pressure-sensitive adhesives.

Of these pressure-sensitive adhesives, those having excellent optical transparency, exhibiting appropriate wettability, cohesiveness and adhesive property, and having excellent weather resistance and heat resistance are preferably used. An acrylic pressure-sensitive adhesive is preferably used as this feature.

As a method of forming the pressure-sensitive adhesive layer, for example, a method of applying the pressure-sensitive adhesive to a separator or the like having a peeled-off treatment, drying and removing a polymerization solvent or the like to form a pressure-sensitive adhesive layer, and then transferring the layer to the flexible polarizing film, A method in which a pressure sensitive adhesive layer is formed on a polarizer by applying and drying a polymerization solvent or the like. Further, in applying the pressure-sensitive adhesive, at least one solvent other than the polymerization solvent may be newly added.

The thickness of the pressure-sensitive adhesive layer is not particularly limited and is, for example, about 1 to 100 mu m. Preferably 2 to 50 占 퐉, more preferably 2 to 40 占 퐉, and still more preferably 5 to 35 占 퐉.

When the pressure-sensitive adhesive layer is exposed, the pressure-sensitive adhesive layer may be protected with a sheet (separator) which has been peeled off until it is provided for practical use.

<Surface Protective Film>

The surface protective film may be provided on the flexible polarizing film of the present invention. The surface protective film usually has a base film and a pressure-sensitive adhesive layer, and protects the flexible polarizing film through the pressure-sensitive adhesive layer.

As the base film of the surface protective film, a film material having isotropy or isotropy is selected from the viewpoint of inspection property and manageability. Examples of the film material include a polyester resin such as a polyethylene terephthalate film, a cellulose resin, an acetate resin, a polyether sulfone resin, a polycarbonate resin, a polyamide resin, a polyimide resin, a polyolefin resin And transparent polymers such as resins and acrylic resins. Among these, a polyester resin is preferable. The base film may be used as a laminate of one kind or two or more kinds of film materials, or a stretched product of the film may be used. The thickness of the base film is generally 500 탆 or less, preferably 10 to 200 탆.

As the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer of the surface protective film, a pressure-sensitive adhesive using a polymer such as a (meth) acryl-based polymer, a silicone-based polymer, a polyester, a polyurethane, a polyamide, a polyether, have. From the viewpoints of transparency, weather resistance, heat resistance and the like, an acrylic pressure sensitive adhesive using an acrylic polymer as a base polymer is preferable. The thickness (dry film thickness) of the pressure-sensitive adhesive layer is determined according to the required adhesive force. But is usually about 1 to 100 mu m, preferably 5 to 50 mu m.

The surface protective film may be provided with a peeling treatment layer on the opposite surface of the base film on which the pressure-sensitive adhesive layer is provided by a low-adhesive material such as silicone treatment, long-chain alkyl treatment or fluorine treatment.

<Other optical layers>

The flexible polarizing film of the present invention can be used for various applications that can not be applied to a conventional polarizer or polarizing film as a substitute for a polarizer or a polarizing film (a polarizing film provided with a transparent protective film). For example, It can be used as an optical film laminated with other optical layers. The optical layer is not particularly limited. For example, when the flexible polarizing film of the present invention is used as a substitute for a polarizer, a protective film (including a retardation film, a brightness enhancement film, a diffusion film, etc.) used for protecting the polarizer is used When used as a substitute for a polarizing film, a liquid crystal display device, an organic EL display device, or the like, such as a reflection plate or a transflective plate, a retardation film (including a wave plate of ½ or ¼) An optical layer which may be used for the formation of an image display device of one or more layers.

<Intervening layer>

The optical layer and the flexible polarizing film can be laminated via an intervening layer such as an adhesive layer, a pressure-sensitive adhesive layer, and an undercoat layer (primer layer). At this time, it is preferable to stack the both without air gap by the interposition layer.

The flexible polarizing film of the present invention or an optical film using the same can be suitably used for forming various image display devices such as a liquid crystal display device and an organic EL display device. The formation of the liquid crystal display device can be performed in a conventional manner. That is, the liquid crystal display device is generally formed by appropriately assembling the liquid crystal cell, the flexible polarizing film of the present invention or an optical film using the flexible film, and a lighting system, if necessary, and incorporating a driving circuit. Except that the flexible polarizing film of the present invention is used. As for the liquid crystal cell, any kind of IPS type or VA type, for example, can be used, and it is particularly preferable for the IPS type.

[Example]

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the following examples. In the examples, all parts and percentages are based on weight. The conditions at room temperature, which are not specifically limited below, are all 23 deg. C and 65% RH.

<Fabrication of Polarizer A0>

(IPA copolymerized PET) film (thickness: 100 占 퐉) of amorphous isophthalic acid copolymerized polyethylene terephthalate (thickness: 100 占 퐉) having a water absorption rate of 0.75% and a Tg of 75 占 폚 was subjected to corona treatment on one side of the substrate. Polyvinyl alcohol , 99.0% by mol), and acetoacetyl modified PVA (polymerization degree: 1,200, degree of acetoacetyl modification of 4.6%, degree of saponification of 99.0 mol% or more, trade name: GOSHEIMAIMER Z200, manufactured by Nippon Gosei Chemical Industry Co., Was applied at 25 캜 and dried to form a PVA resin layer having a thickness of 11 탆, thereby preparing a laminate.

The obtained laminate was free-end uniaxially stretched in an oven at 120 캜 in the longitudinal direction (lengthwise direction) between free rolls different in the main speed (air assisted stretching process).

Subsequently, the laminate was immersed (insolubilization treatment) for 30 seconds in an insolubilizing bath (a boric acid aqueous solution obtained by mixing 4 parts by weight of boric acid with 100 parts by weight of water) at a liquid temperature of 30 占 폚.

Subsequently, the polarizing plate was immersed in a dyeing bath at a liquid temperature of 30 캜 while adjusting the iodine concentration and the immersion time so that the polarizing plate had a predetermined transmittance. In this Example, 0.2 part by weight of iodine was blended with 100 parts by weight of water, and 1.0 part by weight of potassium iodide was blended, followed by immersion for 60 seconds in an aqueous iodine solution (dyeing treatment).

Subsequently, the resultant was immersed in a crosslinking bath (aqueous solution of boric acid obtained by mixing 3 parts by weight of potassium iodide and 3 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30 占 폚 for 30 seconds (crosslinking treatment).

Thereafter, the laminate was immersed in a boric acid aqueous solution having a liquid temperature of 70 DEG C (an aqueous solution obtained by mixing 4 parts by weight of boric acid and 5 parts by weight of potassium iodide with respect to 100 parts by weight of water) And the uniaxial stretching was performed so that the total draw ratio was 5.5 times in the direction (length direction) (underwater stretching treatment)

Thereafter, the laminate was immersed in a cleansing bath (an aqueous solution obtained by mixing 4 parts by weight of potassium iodide with respect to 100 parts by weight of water) at a liquid temperature of 30 DEG C (washing treatment).

Thus, an optical film laminate comprising a polarizer having a thickness of 5 탆 was obtained.

&Lt; Fabrication of Polarizer (A1-A2) >

Polarizers (A1-A2) were produced in the same manner as in the production of polarizer (A0) except that the production conditions of the polarizer (A0) were changed as shown in Table 1. Table 1 shows the thicknesses, optical characteristics (single transmittance, polarization degree) and boric acid concentrations of the polarizers A0 to A2.

[Table 1]

&Lt; Production of Polarizer B1 (Polarizer with 12 占 퐉 thickness)

A polyvinyl alcohol film having an average degree of polymerization of 2,400 and a degree of saponification of 99.9 mol% and a thickness of 30 mu m was immersed in hot water at 30 DEG C for 60 seconds to swell. Subsequently, the film was dipped in an aqueous solution having a concentration of 0.3% of iodine / potassium iodide (weight ratio = 0.5 / 8) and stretched to 3.5 times. Thereafter, it was stretched so as to have a total draw ratio of 6 in an aqueous solution of boric ester at 65 캜. After stretching, it was dried in an oven at 40 캜 for 3 minutes to obtain a polarizer (B1). The thickness of the obtained polarizer B1 was 12 占 퐉. The optical characteristics of the obtained polarizer (B1) had a transmittance of 42.8% and a polarization degree of 99.99%.

&Lt; Production of Polarizer B2 (Polarizer with a Thickness of 23 탆)

A polyvinyl alcohol film having an average degree of polymerization of 2,400 and a saponification degree of 99.9 mol% and a thickness of 75 mu m was immersed in hot water at 30 DEG C for 60 seconds to swell. Subsequently, the film was dipped in an aqueous solution having a concentration of 0.3% of iodine / potassium iodide (weight ratio = 0.5 / 8) and stretched to 3.5 times. Thereafter, it was stretched so as to have a total draw ratio of 6 in an aqueous solution of boric ester at 65 캜. After stretching, it was dried in an oven at 40 DEG C for 3 minutes to obtain a polarizer B2. The thickness of the obtained polarizer B2 was 23 占 퐉. The optical characteristics of the obtained polarizer B2 were 42.8% in transmittance and 99.99% in polarization.

&Lt; Material for forming reinforcement film &

(1) Polyurethane-based materials

50 parts of a polycarbonate polyol (Desmophen C3100XP, manufactured by Sumika Bayer Urethane Co., Ltd.), 50 parts of a urethane prepolymer composed of tolylene isocyanate and trimethylol propane (Coronate L, manufactured by Tosoh Corporation) 0.1 part of Enzizer OL-1 manufactured by Fine Chemical Co., Ltd.) was added, and a solid content concentration of 35% was adjusted using methyl isobutyl ketone as a solvent to obtain a coating solution.

(2) UV hardening material

50 parts of a urethane acrylate oligomer (manufactured by Nippon Gosei Chemical Industry Co., Ltd., Magnetite UV1700TL) was added with a reaction product of 2-hydroxyethyl acrylate and a polymer having a constituent component of 1,6-diisocyanatohexane (manufactured by BASF, Rome LR9000) and 3 parts of a photoinitiator (IRGACURE 907, manufactured by BASF) were added to the mixture, and the solid concentration was adjusted to 35% by using methyl isobutyl ketone as a solvent to obtain a coating liquid.

(3) Water-based resin emulsion material

Pure water as a solvent was added to an acrylic emulsion (trade name: SE-2915E, manufactured by TAISEI PINE CHEMICAL CO., LTD.) To prepare a coating liquid having a solid concentration of 30%.

<Protective film (acrylic) and adhesive>

(Adhesive) treated surface of a (meth) acrylic resin film having a lactone ring structure with a thickness of 20 mu m was subjected to corona treatment.

40 parts by weight of N-hydroxyethylacrylamide (HEAA), 60 parts by weight of acryloylmorpholine (ACMO) and 3 parts by weight of a photoinitiator "IRGACURE 819" (manufactured by BASF) as an adhesive to be applied to the protective film (acrylic) Were mixed to prepare an ultraviolet curable adhesive.

Example 1 (Fabrication of Flexible Polarizing Film)

The polyurethane material (1) of the reinforcing film was applied to a polarizer (first face) of the polarizer A0 (optical film laminate including the polarizer having a thickness of 5 m) obtained above by using a wire bar coater, Mu] m, and then cured at 60 DEG C for 10 minutes. Thereafter, annealing was further performed at 60 DEG C for 12 hours to form a first reinforcing film. Subsequently, a surface protective film (RP301, manufactured by Nitto Denko Corporation) was applied onto the first reinforcing film, and then the amorphous PET substrate of the optical film laminate was peeled off. Thereafter, the polyurethane material (1) of the reinforcing membrane was coated on the polarizer (the second side to be peeled) with a wire bar coater so as to have a thickness of 5 mu m after cured, and then subjected to initial curing Thereafter, an annealing treatment was further performed under the condition of 60 占 폚 for 12 hours to form a second reinforcing film. Thereafter, the surface protective film fused on the first reinforcing film was peeled off to obtain a flexible polarizing film having a reinforcing film on both surfaces of the polarizer.

Examples 2 to 4

A flexible polarizing film having a reinforcing film on both surfaces of a polarizer was prepared in the same manner as in Example 1 except that the kind of polarizer and the thickness of the reinforcing film were changed as shown in Table 2 in Example 1. [

Example 5 (Fabrication of Flexible Polarizing Film)

The UV curable material (2) of the reinforcing film was cured on the polarizer (first side) of the polarizer A0 (the optical film laminate including the polarizer having a thickness of 5 m) obtained above by using a wire bar coater 5 탆, and then heated at 60 캜 for 1 minute. The coated film after heating was irradiated with ultraviolet rays having a cumulative light quantity of 300 mJ / cm ² with a high-pressure mercury lamp to form a first reinforcing film. Subsequently, a surface protective film (RP301, manufactured by Nitto Denko Corporation) was applied onto the first reinforcing film, and then the amorphous PET substrate of the optical film laminate was peeled off. Thereafter, the UV curable material (2) of the reinforcing film was coated on the polarizer (the second side that is the release side) with a wire bar coater so as to have a thickness of 5 탆 after curing, and then heated at 60 캜 for 1 minute. A second reinforcing film was formed by irradiating ultraviolet rays of a total light quantity of 300 mJ / cm &lt; 2 &gt; with a high-pressure mercury lamp to the coated film after heating. Thereafter, the surface protective film bonded to the first reinforcing film was peeled off to obtain a flexible polarizing film having a reinforcing film on both surfaces of the polarizer.

Example 6 (Fabrication of Flexible Polarizing Film)

The water-based resin emulsion material (3) of the reinforcing film was cured on the polarizer (first face) of the polarizer (A0) (optical film laminate including the polarizer having a thickness of 5 m) 5 탆, and then cured at 80 캜 for 5 minutes to form a first reinforcing film. Subsequently, a surface protective film (RP301, manufactured by Nitto Denko Corporation) was applied onto the first reinforcing film, and then the amorphous PET substrate of the optical film laminate was peeled off. Thereafter, the water-based resin emulsion material (3) of the reinforcing membrane was coated on the polarizer (the second face as the release face) so as to have a thickness of 5 mu m after cured using a wire bar coater, and then cured To form a second reinforcing film. Thereafter, the surface protective film fused on the first reinforcing film was peeled off to obtain a flexible polarizing film having a reinforcing film on both surfaces of the polarizer.

Example 7

A flexible polarizing film having a second reinforcing film on only one side of the polarizer was produced in the same manner as in Example 1 except that the first reinforcing film was not provided.

Example 8

A flexible polarizing film having a first reinforcing film on only one side of the polarizer was produced in the same manner as in Example 1 except that the second reinforcing film was not provided.

Comparative Examples 1 to 3

A polarizing film having a reinforcing film on both sides of the polarizer was prepared in the same manner as in Example 1 except that the kind of polarizer and the thickness of the reinforcing film were changed as shown in Table 2 in Example 1. [

Comparative Example 4 (Production of protective polarizing film)

The ultraviolet curable adhesive was applied to the polarizer (first side) of the polarizer A0 (optical film laminate including the polarizer having a thickness of 5 m) obtained above and the thickness of the cured adhesive layer was 1 占 퐉, (Acrylic) was cured, and ultraviolet rays were irradiated as an active energy ray to cure the adhesive. UV light irradiation was performed using a gallium-containing metal halide lamp, irradiation apparatus: Light HAMMER10 valve manufactured by Fusion UV Systems, Inc. V valve, peak illuminance: 1600 mW / cm 2, cumulative irradiation amount 1000 / mJ / cm 2 (wavelength 380-440 nm) , And the illuminance of ultraviolet rays was measured using Sola-Check system manufactured by Solatell. Subsequently, the amorphous PET substrate of the optical film laminate was peeled off to obtain a polarized protective polarizing film.

A sample was prepared for the polarizing film and polarizing polarizing film having the flexible polarizing film obtained in the above example and the reinforcing film obtained in the comparative example, and the following evaluation was carried out. The results are shown in Table 2. In Comparative Examples 5 to 7, evaluation was made for the single polarizers (A0, A1, B1). Polarizers A0 and A1 having thin film thicknesses were withdrawn, and evaluation in a group was impossible to measure except laminating property. The evaluation was carried out at 23 DEG C and 65% RH.

&Lt; Bulk transmittance (T) and polarization degree (P) of polarizer >

The basic transmittance (T) and the degree of polarization (P) of the obtained polarizing film were measured using a spectral transmittance measuring instrument with an integrating sphere (Dot-3c, Murakami Color Research Laboratory).

The degree of polarization P is calculated from the transmittance (parallel transmittance: Tp) in the case where two identical polarizing films are superimposed so that the transmission axes thereof are parallel to each other and the transmittance (orthogonal transmittance: Tc) to the following formula.

(%) = {(Tp-Tc) / (Tp + Tc)} ^1/2 100

Each transmittance is represented by a Y value corrected for visibility by a 2-degree field of view (C light source) of JIS Z8701 with 100% of complete polarization obtained through a Glan Taylor prism.

&Lt; Measurement of compressive modulus of elasticity &

TI900 TriboIndenter (manufactured by Hysitron) was used for measurement of compressive modulus. The obtained polarizing film (polarizing film) with a reinforcing membrane was cut into a size of 10 mm x 10 mm, fixed to a support of a tribolndenter apparatus, and the compression elastic modulus was measured by the nanoindentation method. At this time, the position of the use indenter was adjusted so as to press the vicinity of the center of the transparent layer. Measurement conditions are shown below.

Used indenter: Berkovich (triangular)

Measuring method: Single indentation measurement

Measuring temperature: 23 ° C

Indentation depth setting: 100nm

<Torsion (Thinning) Test>

(Main body: TCDM111LH and jig: no-load torsion test jig for the surface body) manufactured by Yuasa Systems Co., Ltd.

(Both sides) of a rectangular object (1, rectangular) (sample) having a length of 100 mm (absorption axis direction) × 150 mm (transmission axis direction) The other side of the clip 11 on the short side was twisted under the following conditions while being fixed with the clip 12. The twisted state is shown in Fig.

Torsion speed: 10 rpm

Torsion angle: 45 degrees

Torsion frequency: 100 times

The state of the sample after the torsion test was visually evaluated by the following criteria.

?: Cracks and light leakage did not occur. Also, no folds were left.

C: Cracks and light leakage did not occur. But there was a fold left.

X: Cracks and light leakage occurred. Also, the folds remained.

&Lt; U &lt;

(Product name: main body DLDM111LH and jig: surface unloaded U uniaxial stretching test jig) manufactured by Yuasa System Co., Ltd.

Both ends (x, y) (50 mm) of the rectangular object 1 (sample) of 50 mm (absorption axis direction) × 100 mm (transmission axis direction) were attached to the supporting portions 21, , And then stretched and contracted such that the one surface side (first surface) of the rectangular object 1 became U-shape inward, and the rectangular object was bent (the first surface side in the transmission axis direction . Fig. 3 shows the state of a process of the U axis expansion and contraction. In the U axis, the bending radius (bending radius) was set to be 0, and the rectangular object 1 (sample) was bent from the plane state until it contacted in a folded state. The bending is performed such that both end portions (x, y) are brought into contact with both end portions (x, y) by the operation of the support portion and the other portions of the rectangular object 1 (sample) ) So as to be brought into contact with each other from no outer side to no load.

Further, the bending due to the expansion and contraction was performed in the same manner as described above (bending of the second surface side in the transmission axis direction) in which the U-shape was inward with respect to the other side (second surface) of the rectangular object.

The elongation and bending by the expansion and contraction was performed in the same manner as described above for a rectangular object (sample) of 50 mm (transmission axis direction) × 100 mm (absorption axis direction) such that the first and second surfaces were inward U- (Bending of the first surface side and the second surface side in the absorption axis direction).

Stretching speed: 30 rpm

Bending (R): 0

Number of construction: 100 times

The state of the U-shaped elastic test sample was visually evaluated by the following criteria.

?: No cracks or light leakage occurred in any of the bending of the first surface side and the second surface side in the transmission axis direction, and the bending of the first surface side and the second surface side in the absorption axis direction. Also, there were no folds left.

C: Cracks or light leakage occurred in any of the bending of the first surface side and the second surface side in the transmission axis direction, and the bending of the first surface side and the second surface side in the absorption axis direction. Or folds were identified.

The criteria of the twist test, the crack in the U-shaped elongation and shrinkage test, the folded marks and the cracking are as follows.

"Crack" indicates that the sample (the entire layer constituting the flexible polarizing film, the polarizing film having the reinforcing film, or the layer constituting the protective polarizing film or a part thereof) penetrates, and tearing or cracking occurs.

The " folded mark " refers to a visible mark which remains on the sample (a flexible polarizing film, a polarizing film having a reinforcing film, or a whole layer or a part thereof constituting the protective polarizing film) Is generated.

&Quot; Light leakage " indicates that the polarizer itself is torn or cracked. Confirmation of the leakage can be confirmed by pasting the sample (the entire layer constituting the flexible polarizing film, the reinforcing film, or the protective polarizing film) and other conventional polarizing films after the test on both sides of the glass in cross-Nicol state, And light.

&Lt; Bending test >

A rectangular object 1 (sample) of 200 mm (absorption axis direction) × 300 mm (transmission axis direction) was provided on a horizontal stand 31. Subsequently, the rectangular object 1 was folded into three pieces in the direction of the transmission axis (long axis direction), and then a load 32 of 100 g was stuck thereon so that a load was applied to the entire uppermost portion, and left for 5 minutes. The state of bending is shown in Fig. Thereafter, the load 32 was removed.

The same operation was performed on the rectangular object (sample) of 200 mm (transmission axis direction) × 300 mm (absorption axis direction) (the sample was folded in three in the absorption axis direction (long axis direction)).

After the bending maintenance test, whether or not the sample was held in a folded state was visually confirmed. When three folded shapes were maintained, the sample was returned to its original state (plane) and visually evaluated based on the following criteria. The evaluation was performed three times for each of the long side in the transmission axis direction and the long side in the absorption axis direction.

∘: In any sample, three folded shapes were maintained, and no cracks were observed and the original state was maintained (retentive).

X: Three folded shapes were not retained in any one sample. Alternatively, three folded shapes were maintained, but cracks were generated at the time of loading (no retentivity).

Further, the judgment of " crack " is the same as the above-mentioned twist test and U-shaped elastic shrinkage test.

<Lecture test>

No. Of Yasuda Seiki Works. A 476 cantilever type flexibility tester was used. In addition, in this test, in order to eliminate the influence of the static electricity, samples and the like used for the test were appropriately subjected to static elimination.

A rectangular object 1 (sample) of 50 mm (absorption axis direction) × 150 mm (transmission axis direction) has a plane (50 mm × 150 mm: the same size as the sample) and a slope of 45 ° at one end of the long side (See Fig. 5) so as to be positioned on the top surface of a smooth SUS platform 41 having a trapezoidal cross-section. The sample was installed so that the slope was in the direction of the transmission axis.

The sample was slid to the slope side at an extrusion rate of 10 mm / sec and moved (1). The movement of the sample was stopped at the point where the tip of the sample first contacted the inclined surface (2). The distance (L) (mm) in which the sample moved the plane in the plane was measured.

The same operation as above was performed on the rectangular object 1 (sample of the flexible polarizing film) in the direction of 50 mm (transmission axis direction) × 150 mm (absorption axis direction) (provided that the sample was inclined in the absorption axis direction) .

The polish degree (mm) was 3 for each of the two patterns of the sample in which the first side was set to the upper side and the second side was set to the upper side with respect to the long side of the transmission axis direction and the long side of the absorption axis direction, And the shortest straight line distance L (mm) were measured (a total of 12 samples), and their arithmetic mean values were determined.

In addition, in the case of one or more measurements of any one of the twelve samples, when there is a sample that can not be measured due to deformation or curl of the sample, the sample was judged to be unmeasurable.

<Tensile test>

(A sample of a flexible polarizing film) was prepared by cutting it into a predetermined shape of 10 mm (absorption axis direction) x 150 mm (transmission axis direction) with a multipurpose test piece cutter (dumbbell).

The sample was subjected to a tensile test at a tensile rate of 50 mm / min using Autograph AG-IS manufactured by Shimadzu Corporation.

The sample was carried out while both sides of the transmission axis direction were fixed with clamps 51 and 52 (the distance 53 between the initial clamps was 50 mm) while pulling one of the clamps 52 side ). The point at which the sample started fracturing or plastic deformation was evaluated as " tensile strength ".

The tensile strength was determined as the arithmetic average of the results measured three times.

[Table 2]

1 flexible polarizing film
a transparent protective film
b1 first reinforcing membrane
b2 Second reinforcement membrane

Claims (17)

A polyvinyl alcohol-based polarizer having a thickness of 10 占 퐉 or less in which a polyvinyl alcohol-based resin is oriented in one direction and an iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-based resin, And a reinforcing film adhered to at least one surface of the polyvinyl alcohol polarizer in close contact with the polyvinyl alcohol polarizer. The method according to claim 1,
Wherein the thickness of the reinforcing film is 15 占 퐉 or less. 3. The method according to claim 1 or 2,
A first reinforcing film having a thickness of 15 m or less on the first side of the polyvinyl alcohol polarizer and a second reinforcing film having a thickness of 15 m or less on the other side of the second side. The method of claim 3,
Wherein the difference in thickness between the first reinforcing film and the second reinforcing film is 10 占 퐉 or less. 5. The method according to any one of claims 1 to 4,
Wherein the ratio of the thickness of the reinforcing film to the thickness of the polyvinyl alcohol polarizer is 0.4 or more. 6. The method according to any one of claims 1 to 5,
Wherein the reinforcing film has a compressive modulus at 23 占 폚 of 1 MPa or more. 7. The method according to any one of claims 1 to 6,
Wherein the reinforcing film is substantially not oriented. 8. The method according to any one of claims 1 to 7,
Wherein the reinforcing film is a resin film. 9. The method of claim 8,
Wherein the resin film is a thermosetting resin or an active energy ray-curable resin. 10. The method according to any one of claims 1 to 9,
Wherein no cracks, folding marks and light leakage are observed after the bit is twisted (twisted or twisted) in the direction in which the polyvinyl alcohol-based resin is oriented. 11. The method according to any one of claims 1 to 10,
And after stretching and shrinking in a U-shape in a direction perpendicular to the alignment direction in which the polyvinyl alcohol-based resin is oriented and in the direction perpendicular to the alignment direction, a U-shape stretching test is performed in which no cracks, folding marks, Wherein the polarizer is a polarizer. 12. The method according to any one of claims 1 to 11,
After the bending and holding test of bending and holding in the direction in which the polyvinyl alcohol resin is oriented and the direction orthogonal to the alignment direction is carried out, the bending shape is maintained in any direction and no crack is generated A flexible polarizing film characterized by. 13. The method according to any one of claims 1 to 12,
(Mm) is 60 mm or less in a direction of orientation in which the polyvinyl alcohol-based resin is oriented and in a laminating property test in a direction orthogonal to the orientation direction. 14. The method according to any one of claims 1 to 13,
Wherein the tensile strength in a direction orthogonal to the alignment direction in which the polyvinyl alcohol-based resin is oriented in the tensile test is 5 N / 10 mm or more. 15. The method according to any one of claims 1 to 14,
Wherein the polyvinyl alcohol polarizer has an optical property represented by a single transmittance (T) and a polarization degree (P)
P > - (10 ^0.929 T ^-42.4 -1) x 100 (T <42.3), or
P? 99.9 (where T? 42.3). A method for producing a flexible polarizing film according to any one of claims 1 to 15,
(1) a step of preparing a polyvinyl alcohol polarizer having a thickness of 10 탆 or less in which a polyvinyl alcohol-based resin is oriented in one direction and iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-
(2) of coating a liquid material containing a curable component that can constitute a resin component or a resin film on at least one surface of the polyvinyl alcohol polarizer, and thereafter solidifying or curing the liquid material to form a reinforcing film And a second polarizing film. An image display apparatus having the flexible polarizing film according to any one of claims 1 to 15.

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