TWI762500B - Laminated film - Google Patents

Abstract

An object of the present invention is to provide a laminated film capable of maintaining a high polarization degree even in a wet heat environment.

The laminated film comprises a polarizer layer in which dichroic dye is oriented in polyvinyl alcohol resin, a resin layer which comprises a resin film having a slow axis in a direction with respect to the absorption axis of polarizer layer, and an adhesive layer for adhering the polarizer layer and the resin layer, wherein the resin layer has a plasticizer, the adhesive layer has a cured product of the adhesive composition as a forming material, and the adhesive composition has a compound having at least one (meth)acryloyl group in the molecule.

Description

Laminated film

The present invention relates to a laminated film.

Conventionally, polarizing plates have been widely used as polarized light supply elements and polarized light detection elements in display devices such as liquid crystal display devices. A polarizing plate is known to have a configuration in which a protective film is bonded to one or both surfaces of a polarizing film (polarizer layer) using an adhesive or the like.

As a polarizing film, a film containing a polyvinyl alcohol-based resin in which dichroic dyes such as iodine are aligned is known. The iodine system in the polarizing film exists as an iodine complex, and the iodine complex itself is also aligned depending on the alignment of the polyvinyl alcohol-based resin. It is known that this iodine complex absorbs light in the visible light region, whereby the polarizing film exhibits polarization characteristics (polarization degree).

When a polarizing plate is applied to a display device, various optical layers (resin layers) such as a retardation plate having optical properties and an optical compensation film are bonded to the polarizing film provided with a protective film as necessary (for example, Patent Document 1). The optical layer may contain additives such as a plasticizer for the purpose of improving the performance of the film.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2008-80674

However, when the polarizing plate described in Patent Document 1 is placed in a humid and hot environment (for example, in an environment of room temperature of 60° C. and humidity of 95%), the degree of polarization may decrease.

In view of such circumstances, the present invention aims to provide a laminated film capable of maintaining a high degree of polarization even in a humid and heat environment.

In order to solve the above-mentioned problems, the inventors of the present invention, as a result of repeated studies, deduced that the plasticizer contained in the optical layer migrates to the polarizing film and reacts with the iodine complex that contributes to polarization in a humid and hot environment. The iodine complex disappears, and as a result, the polarization degree of the obtained polarizing plate is lowered. On the other hand, the adhesive layer interposed between the polarizing film and the optical layer contains, as a forming material, a cured product of an adhesive composition containing at least one (meth)acryloyl group in the molecule. Based on the compound, it is expected that the migration of the plasticizer to the polarizing film can be inhibited, and the present invention has been completed.

One aspect of the present invention provides a laminate film comprising: a polarizer layer in which a dichroic dye is aligned in a polyvinyl alcohol-based resin; A resin film with a slow axis in the cross direction is used as a forming material; and an adhesive layer, which connects the polarizer layer and the resin layer; wherein, the resin layer contains a plasticizer, and the adhesive layer contains a cured product of the adhesive composition as a The forming material and the adhesive composition include a compound having at least one (meth)acryloyl group in the molecule.

In one aspect of the present invention, both the polarizer layer and the extending film can be elongated.

According to an aspect of the present invention, it is possible to provide a laminated film that can maintain a high degree of polarization even in a humid and hot environment.

1. 2‧‧‧Laminated film

11‧‧‧Polarizer layer

21‧‧‧Resin layer

23‧‧‧Protective film

31, 33‧‧‧Adhesive layer

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the laminated film of the present embodiment.

FIG. 2 is a schematic cross-sectional view showing a modification of the layer structure of the laminated film of the present embodiment.

<Laminated film>

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the laminated film of the present embodiment. As shown in FIG. 1 , the laminate film 1 of the present embodiment includes a polarizer layer 11 , a resin layer 21 , and an adhesive layer 31 for bonding the polarizer layer 11 and the resin layer 21 to each other. In other embodiments, a protective film may be further laminated on the polarizer layer 11 on the opposite side to the resin layer 21 .

The laminated film of the present embodiment may be in a long shape, or may be a sheet-like body obtained by cutting the long laminated film into a predetermined length. The elongated laminated film system includes an elongated polarizer layer and an elongated resin layer. The elongated polarizer layer and the elongated resin layer will be described later.

[Polarizer layer]

The polarizer layer refers to an optical film having a property of absorbing linearly polarized light having a vibration plane parallel to the optical axis and transmitting linearly polarized light having a vibration plane orthogonal to the optical axis. Specifically, the polarizer layer 11 of the present embodiment is a film in which a dichroic dye is aligned in a polyvinyl alcohol-based resin (hereinafter referred to as "PVA-based resin").

The thickness of the polarizer layer 11 is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 15 μm or less, particularly preferably 10 μm or less, and particularly preferably 7 μm or less.

When the polarizer layer 11 is a film in which a dichroic dye is aligned in a PVA-based resin, the polarizer layer 11 can also be obtained by extending a green film containing the PVA-based resin. When the thickness of the polarizer layer 11 is 7 μm or less, the polarizer layer 11 may be obtained by extending the coating film containing the PVA-based resin formed on the base material together with the base material, and then peeling off the base material.

As the substrate which can also be used in this embodiment, polypropylene film, polyethylene terephthalate film, polycarbonate film, cellulose triacetate film, norbornene film, polyester film, Polystyrene film, etc.

As the PVA-based resin used in the present embodiment, a polyvinyl acetate-based resin is saponified. As the polyvinyl acetate-based resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, copolymers of vinyl acetate and other monomers which can be copolymerized therewith can also be cited. Examples of other monomers that can be copolymerized with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, acrylamides having an ammonium group, and the like.

The degree of saponification of the PVA-based resin is preferably 80 mol % or more, more preferably 90 mol % or more and 99.5 mol % or less, and still more preferably 94 mol % or more and 99 mol % or less. When the saponification degree is 80 mol % or more, the heat-and-moisture resistance of the obtained laminated film 1 can be improved. Moreover, when the saponification degree is 99.5 mol % or less, the laminated film 1 which has sufficient polarizing performance can be obtained.

The PVA-based resin may be modified polyvinyl alcohol partially modified. For example, those modified with olefins such as ethylene and propylene; modified with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; modified with alkyl esters of unsaturated carboxylic acids, acrylamide, etc. Modifier.

The modification ratio of the PVA-based resin is preferably less than 30 mol %, more preferably less than 10 mol %. When the PVA-based resin whose modification ratio is less than 30 mol % is used, the dichroic dye can be sufficiently adsorbed, and a polarizer having sufficient polarizing performance can be obtained.

The average degree of polymerization of the PVA-based resin is preferably 100 or more and 10,000 or less, more preferably 1,500 or more and 8,000 or less, and still more preferably 2,000 or more and 5,000 or less. When the average degree of polymerization is 100 or more, a polarizer having sufficient polarization performance can be obtained. Moreover, when an average degree of polymerization is 10,000 or less, the solubility to a solvent becomes favorable, and formation of the film containing a PVA-type resin becomes easy.

PVA-based resins can be easily obtained as commercial products, and as preferred examples of commercial products, they are listed by trade names: "PVA124" and "PVA117" manufactured by KURARAY Co., Ltd. (degree of saponification: 98 to 99 moles) %), "PVA624" (degree of saponification: 95 to 96 mol%), "PVA617" (degree of saponification: 94.5 to 95.5 mol%); "N-300" and "N-300" manufactured by Nippon Synthetic Chemical Industry Co., Ltd. NH-18" (degree of saponification: 98 to 99 mol%), "AH-22" (degree of saponification: 97.5 to 98.5 mol%), "AH-26" (degree of saponification: 97 to 98.8 mol% ); "JC-33" (degree of saponification: more than 99 mol%), "JF-17", "JF-17L" and "JF-20" (degree of saponification: 98) from Japan VAM & POVAL Co., Ltd. to 99 mol %), "JM-26" (degree of saponification: 95.5 to 97.5 mol %), "JM-33" (degree of saponification: 93.5 to 95.5 mol %), "JP-45" (degree of saponification: 86.5 to 89.5 mol%) and so on.

As a dichroic dye used in this embodiment, iodine, a dichroic organic dye, etc. are mentioned. Examples of the dichroic organic dye include red BR, red LR, red R, pink LB, crimson (RUBIN) BL, burgundy GS, sky blue LG, lemon yellow, blue BR, blue 2R, dark blue RY, green LG, violet LB, Purple B, Black H, Black B, Black GSP, Yellow 3G, Yellow R, Orange LR, Orange 3R, Scarlet GL, Scarlet KGL, Congo Red, Bright Purple BK, S Super Blue G, Super Blue GL, Super Orange GL, direct sky blue, direct long prison orange (DIRECT FAST ORANGE) S, long prison black (FAST BLACK).

A dichroic dye may be used individually by 1 type, and may use 2 or more types together.

[resin layer]

The resin layer 21 of the present embodiment uses, as a forming material, a resin film having a slow axis in the oblique direction with respect to the absorption axis of the polarizer layer 11 . Such a resin film system can be produced by a stretching process, and the resin film system has residual tensile stress in the oblique direction with respect to the absorption axis of the polarizer layer 11. Residual stress remaining in the resin film may be one of the causes of a decrease in the degree of polarization of the polarizing plate.

The resin layer 21 has a slow axis in an oblique direction with respect to the absorption axis of the polarizer layer 11 . By making the angle of the slow axis into the above range, the difference between the phase of the light beam in the direction of the fast axis and the phase of the light beam in the direction of the slow axis becomes π/2. Since the phase difference between the fast axis and the slow axis is π/2, when the laminated film 1 of this embodiment is applied to a display device, the light passing through the laminated film 1 can be circularly polarized. Accordingly, even when viewed through polarized glass, a configuration having excellent visibility can be achieved.

The resin layer 21 of the present embodiment is preferably a retardation layer having retardation characteristics and wavelength dispersion characteristics satisfying the following formulae (1) to (4). Since the resin layer 21 satisfies the equations (1) to (4), when the laminated film 1 of the present embodiment is mounted on a display device, viewing of the screen from various directions (azimuthal angle and polar angle) through the polarizing glass can be effectively suppressed. Color changes over time. Thereby, the visibility of the image display device can be improved.

(1)100nm≦R _e (590)≦180nm, (2)0.5<R _th (590)/R _e (590)≦0.8, (3)0.85≦R _e (450)/R _e (550)<1.00 , and (4)1.00<R _e (630)/R _e (550)≦1.1

In the formula, _Re (590), _Re (450), _Re (550), and _Re (630) represent the in-plane retardation values at measurement wavelengths of 590 nm, 450 nm, 550 nm, and 630 nm, respectively, and R _th (590) Indicates the retardation value in the thickness direction at the measurement wavelength of 590 nm. These in-plane retardation values and thickness direction retardation values refer to values measured in an environment with a temperature of 23°C and a relative humidity of 55%.

The in-plane retardation value _Re and the thickness-direction retardation value R _th are defined by the refractive index in the in-plane slow-axis direction as n _x , and the in-plane fast-axis direction (direction orthogonal to the in-plane slow-axis direction) When the refractive index of y is _ny , the refractive index in the thickness direction is _nz , and the thickness of the optical film is d, the following formulas (S1) and (S2) are defined.

(S1)R _e =(n _x -n _y )×d

(S2)R _th =[{(n _x +n _y )/2}-n _z ]×d

_Re (590) in the formula (1) is preferably 105 to 170 nm from the viewpoint of more effectively suppressing the color tone change in the laminated film 1 . R _th (590)/R _e (590) in formula (2) is preferably 0.6 to 0.75. R _e (450)/R _e (550) in formula (3) is preferably 0.86 to 0.98. R _e (630)/R _e (550) in formula (4) is preferably 1.01 to 1.06.

For example, the resin layer 21 can be produced by extending a film containing a resin described later. As the stretching treatment, uniaxial stretching, biaxial stretching, and the like can be mentioned.

As the extending direction, the mechanical flow direction (MD) of the unstretched film, the direction (TD) orthogonal to this, the direction oblique to the mechanical flow direction (MD), etc. are mentioned. Here, the term "unstretched film" refers to a film in which the state is not stretched. Uniaxial stretching refers to stretching the unstretched film in any of these directions. On the other hand, biaxial stretching may be simultaneous biaxial stretching in two stretching directions, or biaxial stretching may be successive biaxial stretching in which stretching is performed in other directions after stretching in a predetermined direction.

For the stretching process, for example, it is possible to stretch the unstretched film in the longitudinal axis direction (machine flow direction: MD) by using two or more pairs of nip rolls with an increased peripheral speed on the outlet side, or to hold the unstretched film by using a chuck. It is carried out by expanding in the direction (TD) orthogonal to the mechanical flow direction on both sides of the end. At this time, the retardation value and the wavelength dispersion can be controlled within the ranges of the above-mentioned formulae (1) to (4) by adjusting the thickness of the film or adjusting the stretching ratio.

Moreover, the wavelength dispersion value can be controlled within the range of the above-mentioned formulae (3) to (4) by adding the wavelength dispersion adjusting agent to the resin.

Generally, a long polarizing film (polarizer layer) has an absorption axis in the longitudinal direction. The two strips are arranged so that the long-length resin layer and the long-length polarizer layer can be bonded to each other in a roll-to-roll manner, and the angle formed between the absorption axis of the polarizer layer and the slow axis of the resin layer is within the above-mentioned range. In other words, the resin layer 21 is preferably manufactured by biaxially extending diagonally.

Examples of resins forming the resin film include cellulose acetate-based resins, cycloolefin-based resins, polyolefin-based resins, acrylic-based resins, polyimide-based resins, polycarbonate-based resins, polyester-based resins, and the like .

The cellulose acetate-based resin is composed of a partial or complete acetate product of cellulose. As a cellulose acetate type resin, a cellulose triacetate, a cellulose diacetate, etc. are mentioned, for example.

Resin films containing cellulose acetate-based resins are readily available on the market, and a preferred example of the commercially available product is listed under the trade name: "FUJITAC (registered trademark) TD80 sold by Fuji Film Co., Ltd. ", "FUJITAC (registered trademark) TD80UF" and "FUJITAC (registered trademark) TD80UZ", "KC8UX2M" and "KC8UY" sold by Konica Minolta Opto Co., Ltd., etc.

Cycloolefin-based resins forming the resin film are, for example, thermoplastic amorphous resins (also called non-crystalline resins) having monomer units containing cyclic olefins (cycloolefins) such as norbornene and polycyclic norbornene-based monomers. crystalline polyolefin resin). The cyclic olefin resin may be a hydrogenated product of a ring-opening polymer of the above-mentioned cycloolefin, a hydrogenated product of a ring-opening copolymer using two or more cyclic olefins, or may be a cyclic olefin, a linear olefin, and/or an aromatic having a vinyl group. Addition copolymers of family compounds, etc. In addition, a polar group may be introduced.

When a resin film is formed using a copolymer of a cycloolefin, a chain olefin, and/or an aromatic compound having a vinyl group, examples of the chain olefin include ethylene, propylene, and the like. Moreover, as the aromatic compound which has a vinyl group, styrene, (alpha)-methylstyrene, the styrene which has an alkyl group substitution on a benzene ring, etc. are mentioned. In such a copolymer, the monomer unit containing the cycloolefin is preferably 50 mol % or less, more preferably 15 to 50 mol %.

In particular, when a terpolymer of an aromatic compound having a cycloolefin, a linear olefin, and a vinyl group is used, the monomer unit containing the cycloolefin can be set to a smaller amount as described above. In such a terpolymer, the unit of the monomer composed of the chain olefin is preferably 5 to 80 mol %. Moreover, it is preferable that the monomer unit containing the aromatic compound which has a vinyl group is 5-80 mol%.

Cycloolefin-based resins can be easily obtained as commercial products, and the preferred examples of the commercial products are listed under the trade name: "TOPAS (registered) manufactured by TOPAS ADVANCED POLYMERS GmbH and sold by POLY PLASTICS Co., Ltd. in Japan. trademark)", "ARTON (registered trademark)" sold by JSR Co., Ltd., "ZEONOR (registered trademark)" and "ZEONEX (registered trademark)" sold by ZEON Co., Ltd., Mitsui Chemicals Co., Ltd. "APEL (registered trademark)" sold by the company, etc.

When the resin layer 21 of the present embodiment is a retardation layer, the thickness of the retardation layer is preferably 10 μm or more and 50 μm or less.

The resin layer 21 of the present embodiment may contain a plasticizer for the purpose of imparting flexibility to the resin film and making it easy to stretch, in addition to the resin forming the resin film. As a plasticizer, polyhydric alcohols, such as ethylene glycol, glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, and trimethylolpropane, can be mentioned.

Only one type of plasticizer may be used, or two or more types may be used in combination. In particular, ethylene glycol and glycerol are suitable.

[adhesive layer]

The adhesive layer 31 of the present embodiment contains a cured product of the adhesive composition as a forming material (hereinafter, the "adhesive composition" may be referred to as "the present composition"). The adhesive composition includes a compound having at least one (meth)acryloyl group in the molecule. Compounds having at least one (meth)acryloyl group in the molecule include compounds having at least one (meth)acryloyloxy group in the molecule (hereinafter, referred to as "(meth)acrylic acid-based compounds) "Compound"), a compound having at least one (meth)acrylamido group in the molecule (hereinafter, sometimes referred to as "(meth)acrylamido compound"), and the like. These compounds are radically polymerizable compounds and can be cured by irradiation with active energy rays (eg, ultraviolet rays, visible light, electron rays, X-rays, etc.).

In this specification, the "(meth)acryloyl group" refers to a methacryloyl group or an acryl group. In addition, the so-called "(meth)acryloyloxy group" and "(meth)acryloylamino group" are also the same as those described above.

The thickness of the adhesive layer is preferably 0.01 μm or more and 5 μm or less, more preferably 0.01 μm or more and 2 μm or less, and still more preferably 0.01 μm or more and 1 μm or less. When the thickness of the adhesive layer 31 is 0.01 μm or more, sufficient adhesiveness can be obtained. Moreover, when the thickness of the adhesive agent layer 31 is 5 micrometers or less, the laminated|multilayer film 1 is hard to become an external appearance defect.

The adhesive layer is preferably selected from an evaluation sample obtained by coating the adhesive composition on a cellulose triacetate film with a thickness of 2 to 3 μm and then hardening it, and the moisture permeability of the evaluation sample is 300g/m ² ‧24 hours or less. The lower limit value of the moisture permeability is not particularly limited, but is, for example, 50 g/m ² ·24 hours. By using such an adhesive layer with moisture permeability, the decrease in the degree of polarization can be made smaller.

The evaluation sample can be produced in the following manner. First, the adhesive composition is applied on the cellulose triacetate film so as to have a thickness of 2 to 3 μm to form an adhesive composition layer. As a cellulose triacetate film for measuring the moisture permeability of the evaluation sample, a thickness of 57.5 μm and a moisture permeability [value calculated by the cup method (JIS Z 0208, temperature 40°C, humidity 90% RH) were used ] is 553g/m ² ‧24 hours. Next, from the adhesive composition layer side, ultraviolet rays were irradiated so that the cumulative light amount would be 400 mJ/cm ² , and the adhesive composition layer was hardened to serve as an evaluation sample. The moisture permeability of the obtained evaluation sample was measured by the cup method (JIS Z 0208, temperature 40°C, humidity 90%RH).

(radical polymerizable compound)

Examples of the (meth)acrylic compound used in the present embodiment include (meth)acrylate monomers having at least one (meth)acryloyloxy group in the molecule, and at least two (meth)acrylate monomers having at least one (meth)acryloyloxy group in the molecule. (meth)acrylate oligomer of a (meth)acryloyloxy group, etc. Each of these systems may be used alone, or two or more of them may be used in combination. When two or more types are used in combination, two or more (meth)acrylate monomers may be used, two or more (meth)acrylate oligomers may be used, and of course one (meth)acrylate monomer may be used in combination above and one or more (meth)acrylate oligomers.

As the above-mentioned (meth)acrylate monomer, a monofunctional (meth)acrylate monomer having one (meth)acryloyloxy group in a molecule, a monofunctional (meth)acrylate monomer having two (methyl) ) A bifunctional (meth)acrylate monomer of acryloxy group and a polyfunctional (meth)acrylate monomer having three or more (meth)acryloyloxy groups in the molecule.

Examples of monofunctional (meth)acrylate monomers include tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, and 2- or 3-hydroxypropyl (meth)acrylate. , 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, methyl (meth)acrylate, (meth)acrylate base) ethyl acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethyl (meth)acrylate Ethylhexyl, isononyl (meth)acrylate, cyclohexyl (meth)acrylate, 1,4-cyclohexanedimethanol monoacrylate, dicyclopentyl (meth)acrylate, (meth)acrylic acid Dicyclopentenyl, benzyl (meth)acrylate, isobornyl (meth)acrylate, phenoxyethyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, Dimethylaminoethyl (meth)acrylate, ethyl carbitol (meth)acrylate, trimethylolpropane mono(meth)acrylate, neotaerythritol mono(meth)acrylate, Polyethylene glycol (meth) phenoxy acrylate, etc.

As a monofunctional (meth)acrylate monomer, a carboxyl group-containing (meth)acrylate monomer can also be used. Examples of monofunctional (meth)acrylate monomers containing a carboxyl group include: 2-(meth)acryloyloxyethylphthalic acid, 2-(meth)acryloyloxyethylhexahydrophthalic acid Phthalic acid, carboxyethyl (meth)acrylate, 2-(meth)acryloyloxyethylsuccinic acid, N-(meth)acryloyloxy-N',N'-dicarboxymethyl- p-phenylenediamine, 4-(meth)acryloyloxyethyl trimellitic acid, etc.

As the (meth)acrylamide-based compound used in the present embodiment, an N-substituted (meth)acrylamide compound is exemplified. The N-substituted (meth)acrylamide compound is a (meth)acrylamide compound having a substituent at the N-position. A typical example of such a substituent is an alkyl group. Substituents at the N-position may be bonded to each other to form a ring, and -CH ₂ - constituting the ring may also be substituted by an oxygen atom. Further, a substituent such as an alkyl group and a pendant oxy group (=O) may be bonded to the carbon atoms constituting the ring. N-substituted (meth)acrylamides can generally be produced by reacting (meth)acrylic acid or its chloride with primary or secondary amines.

The N-substituted (meth)acrylamido compound is preferably a compound represented by the following formula (III). In the following formula (III), Q ¹ represents a hydrogen atom or a methyl group, Q ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Q ³ represents an alkyl group having 1 to 6 carbon atoms which may have a hydroxyl group or an amine group, Or Q ² and Q ³ are bonded to each other to form a 5-membered ring or a 6-membered ring in which -CH _2- can be substituted by an oxygen atom. The hydrogen atom of the aforementioned amine group may be substituted with an alkyl group.

唑烷酮-3-基〔C₂H₄OC(=O)N-〕、哌啶基(C₅H₁₀N-)、嗎啉基(C₂H₄OC₂H₄N-)等。 As an example in which Q ³ is an alkyl group having a hydroxyl group, a hydroxyalkyl group can be mentioned. Q ³ is an example of an alkyl group having an amino group, and examples thereof include an aminoalkyl group, an N-alkylaminoalkyl group, and an N,N-dialkylaminoalkyl group. Q ² and Q ³ can be bonded to each other to form a 5-membered ring or a 6-membered ring in which -CH _2- can be substituted by an oxygen atom. For the example of the 5-membered ring or 6-membered ring, if the N-position is bonded to a carbonyl group ( C=O) in the form of radicals, for example: 1-pyrrolidinyl (C ₄ H ₈ N-), 2-

oxazolidin-3-yl [C ₂ H ₄ OC(=O)N-], piperidinyl (C ₅ H ₁₀ N-), morpholinyl (C ₂ H ₄ OC ₂ H ₄ N-) and the like.

As the N-substituted (meth)acrylamide compound in which Q ² is a hydrogen atom and Q ³ is an alkyl group, there are N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide Amine, N-isopropyl(meth)acrylamide, N-butyl(meth)acrylamide, N-tert-butyl(meth)acrylamide, N-hexyl(meth)acrylamide Amines etc. Similarly, as N-substituted (meth)acrylamides in which both Q ² and Q ³ are alkyl groups, N,N-dimethyl (meth)acrylamides, N,N-diethyl (meth)acrylamide, etc.

As the N-substituted (meth)acrylamide compound in which ^Q2 is a hydrogen atom and ^Q3 is an alkyl group having a hydroxyl group, there are N-methylol (meth)acrylamide, N-(2-hydroxyl group) Ethyl) (meth) acrylamide, N-(2-hydroxypropyl) (meth) acrylamide, etc. As an N-substituted (meth)acrylamide compound in which Q ² is a hydrogen atom and Q ³ is an alkyl group having an amino group, N-[2-(N,N-dimethylamino)ethyl [methyl](meth)acrylamide, N-[2-(N,N-diethylamino)ethyl](meth)acrylamide, N-[3-(N,N-dimethylamino) amino)propyl](meth)acrylamide, N-[1-methyl-1-(N,N-dimethylamino)ethyl](meth)acrylamide and the like.

唑烷酮、4-丙烯醯基嗎啉、N-丙烯醯基哌啶、N-甲基丙烯醯基哌啶等。 As the N-substituted (meth)acrylamido compound in which Q ² and Q ³ are bonded to each other to form a 5-membered ring or 6-membered ring in which -CH _2- may be substituted by an oxygen atom, N-acryloyl amide can be exemplified. Pyrrolidine, 3-propenyl-2-

oxazolidinone, 4-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, etc.

Among the above-mentioned N-substituted (meth)acrylamide compounds, N-hydroxyalkyl (methyl) groups such as N-methylol acrylamide and N-(2-hydroxyethyl)acrylamide are preferred Acrylamide, and N,N-dialkyl(meth)acrylamides such as N,N-dimethylacrylamide and N,N-diethylacrylamide; particularly preferably N-(2 -Hydroxyethyl) acrylamide or N,N-dimethylacrylamide.

Others, such as N-dodecyl(meth)acrylamide, N-alkyl(meth)acrylamide with long-chain alkyl groups, and N-(methoxymethyl)acrylamide, N-(methoxymethyl)acrylamide, etc. (Ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide and N-(alkoxyalkyl)(methyl) of N-(butoxymethyl)acrylamide Acrylamide can be used as an N-substituted (meth)acrylamide compound constituting an active energy ray curable compound.

烷二醇或二

烷二烷醇之二(甲基)丙烯酸酯、雙酚A或雙酚F的環氧烷加成物之二(甲基)丙烯酸酯、雙酚A或雙酚F之二(甲基)丙烯酸環氧酯等。 As a bifunctional (meth)acrylate monomer, representative examples are: alkanediol di(meth)acrylate, polyoxyalkanediol di(meth)acrylate, haloalkanediol di(meth)acrylate Acrylates, di(meth)acrylates of aliphatic polyols, di(meth)acrylates of hydrogenated dicyclopentadiene or tricyclodecanedialkanol, di(meth)acrylates

Alkanediol or Di

Di(meth)acrylate of alkanedialkanol, di(meth)acrylate of alkylene oxide adduct of bisphenol A or bisphenol F, di(meth)acrylic acid of bisphenol A or bisphenol F Epoxy esters, etc.

烷-2,5-二基二(甲基)丙烯酸酯[別稱：二

烷二醇二(甲 基)丙烯酸酯]、羥基三甲基乙醛與三羥甲基丙烷之縮醛化合物[化學名：2-(2-羥基-1,1-二甲基乙基)-5-乙基-5-羥甲基-1,3-二

烷]之二(甲基)丙烯酸酯、參(羥乙基)三聚異氫酸酯二(甲基)丙烯酸酯等。 As a bifunctional (meth)acrylate monomer, ethylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate may be mentioned. (Meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tris Methylolpropane di(meth)acrylate, neotaerythritol di(meth)acrylate, di(trimethylolpropane)di(meth)acrylate, diethylene glycol di(meth)acrylic acid ester, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate Meth)acrylate, polybutylene glycol di(meth)acrylate, polysiloxane di(meth)acrylate, hydroxytrimethylacetate neopentylglycol di(meth)acrylate, 2, 2-bis[4-(meth)acryloyloxyethoxyethoxyphenyl]propane, 2,2-bis[4-(meth)acryloyloxyethoxyethoxycyclohexyl] Propane, hydrogenated dicyclopentadienyl di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, 1,3-di(meth)acrylate

Alkane-2,5-diyl di(meth)acrylate [other name: two

Alkanediol di(meth)acrylate], acetal compound of hydroxytrimethylacetaldehyde and trimethylolpropane [chemical name: 2-(2-hydroxy-1,1-dimethylethyl)- 5-Ethyl-5-hydroxymethyl-1,3-di

Alkyl] di (meth) acrylate, ginseng (hydroxyethyl) trimer isohydrogen ester di (meth) acrylate and the like.

As trifunctional or higher polyfunctional (meth)acrylate monomers, for example, glycerol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, and di(trimethylolpropane) may be mentioned. ) tri(meth)acrylate, di(trimethylolpropane)tetra(meth)acrylate, neotaerythritol tri(meth)acrylate, neotaerythritol tetra(meth)acrylate, di(meth)acrylate Tri- or higher functional aliphatic polyols of neopentaerythritol tetra(meth)acrylate, dipeotaerythritol penta(meth)acrylate, and dipeutaerythritol hexa(meth)meth)acrylate Poly(meth)acrylate. Other examples include: poly(meth)acrylates of tri- or higher-functional halogenated polyols, tri(meth)acrylates of alkylene oxide adducts of glycerin, and alkylene oxide adducts of trimethylolpropane Tris(meth)acrylate, 1,1,1-para[(meth)acryloyloxyethoxyethoxy]propane, 3(hydroxyethyl)trimeric isohydrogenate ) acrylates, etc.

Examples of (meth)acrylate oligomers include urethane (meth)acrylate oligomers, polyester (meth)acrylate oligomers, and epoxy (meth)acrylate oligomers polymer etc.

Urethane (meth)acrylate oligomer is a compound having urethane bond (-NHCOO-) and at least 2 (meth)acryloyloxy groups in the molecule. Specifically, the urethane reaction product of a hydroxyl group-containing (meth)acrylate monomer having at least one (meth)acryloyloxy group and at least one hydroxyl group in the molecule and a polyisocyanate can be mentioned. , urethane compounds containing terminal isocyanate groups obtained by reacting polyols with polyisocyanates, and (meth)acrylic acids having at least one (meth)acryloyloxy group and at least one hydroxyl group respectively in the molecule Urethane reaction products of ester monomers, etc.

Examples of the hydroxyl group-containing (meth)acrylate monomer used in the urethane reaction include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, (meth)acrylate base) 2-hydroxybutyl acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycerol di(meth)acrylate, trimethylolpropane di(meth)acrylate, neopentyl Tetraol tri(meth)acrylate, dipeotaerythritol penta(meth)acrylate, and the like.

Examples of the polyisocyanate to be supplied to the urethane-forming reaction with the hydroxyl group-containing (meth)acrylate monomer include hexamethylene diisocyanate, lysine diisocyanate, and isophorone diisocyanate. Isocyanates, dicyclohexylmethane diisocyanate, tolyl diisocyanate, xylylene diisocyanate, diisocyanates obtained by hydrogenating aromatic isocyanates among these diisocyanates (for example, hydrogenated Di- or tri-isocyanates such as tolylylene diisocyanate, hydrogenated xylylene diisocyanate, etc.), triphenylmethane triisocyanate, diphenylmethylbenzene triisocyanate and the like, and polymerizing the above diisocyanates The resulting polyisocyanate and the like.

Furthermore, as polyols used to form a terminal isocyanate group-containing urethane compound by reaction with polyisocyanate, in addition to aromatic, aliphatic and alicyclic polyols, Polyester polyol, polyether polyol, etc. are mentioned. As aromatic polyols, 1,4-benzenedimethanol, 1,3-benzenedimethanol, 1,2-benzenedimethanol, 4,4'-naphthalene dimethanol, 3,4'-naphthalene can be mentioned. Dimethanol etc. Examples of aliphatic and alicyclic polyols include 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, and neopentyl glycol. Alcohol, Trimethylolethane, Trimethylolpropane, Di(trimethylolpropane), Neopentaerythritol, Dipivalerythritol, Dimethylolheptane, Dimethylolpropionic Acid, Dimethylolpropane Hydroxymethylbutyric acid, glycerin, hydrogenated bisphenol A, etc.

The polyester polyol is obtained by the dehydration condensation reaction of the above-mentioned polyols and a polycarboxylic acid or an acid anhydride thereof. Examples of polycarboxylic acids or their anhydrides include: succinic acid, succinic anhydride, adipic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, trimellitic acid, trimellitic anhydride, homobenzene Tetraacid, pyromellitic anhydride, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, hexahydrophthalic acid, hexahydrophthalic anhydride, and the like.

In addition to polyalkylene glycol, polyether polyols include polyoxyalkylene-modified polyols obtained by reacting the above-mentioned polyols or dihydroxybenzenes with alkylene oxide.

The polyester (meth)acrylate oligomer refers to a compound having at least two ester bonds and at least two (meth)acryloyloxy groups in the molecule. Specifically, it can be obtained by the dehydration condensation reaction of (meth)acrylic acid, polyvalent carboxylic acid or its acid anhydride, and polyhydric alcohol. Examples of the polyvalent carboxylic acid or its acid anhydride used in the dehydration condensation reaction include succinic acid, succinic anhydride, adipic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and trimellitic acid. Acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, etc. . Moreover, as the polyhydric alcohol used for the dehydration condensation reaction, 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol can be mentioned. Alcohol, Trimethylolethane, Trimethylolpropane, Di(trimethylolpropane), Neopentaerythritol, Dipivalerythritol, Dimethylolheptane, Dimethylolpropionic Acid, Dimethylolpropane Hydroxymethylbutyric acid, glycerin, hydrogenated bisphenol A, etc.

The epoxy (meth)acrylate oligomer can be obtained by addition reaction of the polyglycidyl ether which has at least 2 (meth)acryloyloxy groups in a molecule|numerator, and (meth)acrylic acid. As the polyglycidyl ether used in the addition reaction, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, bis Phenol A diglycidyl ether, etc.

It is recognized that compounds having at least one (meth)acryloyl group in the molecule, in addition to the above-mentioned low affinity with plasticizers, form a cross-linked structure during polymerization, so plasticizers are less likely to invade and contain such compounds. A hardened product of a composition of compounds. Therefore, it can be estimated that in a humid and hot environment (for example, an environment of room temperature of 60° C. and humidity of 95%), even if the plasticizer migrates from the resin layer 21 to the polarizer layer 11 (in the direction of the arrow in FIG. 1 ), Intrusion of plasticizers can also be suppressed.

The content of the radically polymerizable compound is preferably 1 part by mass or more and 70 parts by mass or less, more preferably 10 parts by mass or more and 60 parts by mass or less, with respect to 100 parts by mass of the present composition.

In this composition, the radically polymerizable compound may be used alone or in combination of two or more.

(other ingredients) (cationic polymerizable compound)

In addition to the above-mentioned radical polymerizable compound, this composition may contain a cationic polymerizable initiator as needed. As a cationically polymerizable compound, an oxetane compound, an epoxy compound, etc. are mentioned, for example

As an oxetane compound, 3-ethyl-3-hydroxymethyl oxetane etc. are mentioned, for example.

These oxetane compounds can be easily obtained as commercial products, and commercial products such as "ARON OXETANE (registered trademark) OXT-101" and the like are listed below by the trade names of Toagosei Co., Ltd.

In the present composition, the oxetane compound may be used alone or in combination of two or more.

Moreover, in addition to the above-mentioned radically polymerizable compound, this composition system may contain an epoxy compound as needed. The epoxy compound is one of the cationically polymerizable compounds like the oxetane compound, and can be cured by irradiation with active energy rays. By containing an epoxy compound in this composition, the adhesiveness of the resin layer 21 and the polarizer layer 11 can be improved.

As an epoxy compound, an aromatic epoxy compound, the glycidyl ether of a polyhydric alcohol which has an alicyclic ring, an aliphatic epoxy compound, an alicyclic epoxy compound, etc. are mentioned.

Examples of aromatic epoxy compounds include bisphenol-type epoxy compounds such as diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, and diglycidyl ether of bisphenol S. Resins; such as phenol novolac epoxy resin, cresol novolac epoxy resin and novolak epoxy resin of hydroxybenzaldehyde phenol novolak epoxy resin; such as glycidyl ether of tetrahydroxyphenylmethane, Glycidyl ether of hydroxydiphenyl ketone and polyfunctional epoxy resin of epoxidized polyvinyl phenol, etc.

Examples of glycidyl ethers of polyhydric alcohols having alicyclic rings include cores obtained by selectively hydrogenating aromatic rings of aromatic polyhydric alcohols under pressure in the presence of a catalyst. Hydrogenated polyhydroxy compounds and glycidyl etherification. Examples of aromatic polyols include bisphenol-type compounds such as bisphenol A, bisphenol F, and bisphenol S; Resins; such as tetrahydroxydiphenylmethane, tetrahydroxydiphenyl ketone, polyfunctional compounds of polyvinylphenol, etc.

The alicyclic polyol obtained by hydrogenating the aromatic ring of these aromatic polyols can be reacted with epichlorohydrin to be glycidyl ether.

Among such glycidyl ethers of polyols having an alicyclic ring, preferred ones include diglycidyl ethers of hydrogenated bisphenol A.

As an aliphatic epoxy compound, the polyglycidyl ether etc. of an aliphatic polyol or its alkylene oxide adduct are mentioned. Specifically, diglycidyl ether of 1,4-butanediol; diglycidyl ether of 1,6-hexanediol; triglycidyl ether of glycerin; triglycidyl ethers of ethylene glycol; diglycidyl ethers of polyethylene glycol; diglycidyl ethers of propylene glycol; diglycidyl ethers of neopentyl glycol; such as ethylene glycol, propylene glycol or Polyglycidyl ether of a polyether polyol obtained by adding one or more types of alkylene oxides (ethylene oxide and propylene oxide) to an aliphatic polyol of glycerin.

Moreover, the monofunctional epoxy compound represented by following formula (I) can also be mentioned as an aliphatic epoxy compound. R ¹ may be a branched alkyl group having 1 to 15 carbons. The carbon number of the alkyl group is preferably 6 or more, more preferably 6 to 10. Of these, branched alkyl groups are preferred. As the monofunctional epoxy compound represented by formula (I), 2-ethylhexylglycidyl ether can be mentioned.

The alicyclic epoxy compound refers to a compound having at least one in the molecule which forms an ethylene oxide ring structure together with the carbon atom of the alicyclic ring. Here, "the ethylene oxide ring structure is formed together with the carbon atoms of the alicyclic ring" means a structure represented by the following formula (II). n in the formula is an integer of 2 to 5.

The group in the form in which one or a plurality of hydrogen atoms in (CH ₂ )n of the formula (II) is removed is bonded to a compound of another chemical structure to form an alicyclic epoxy compound. In addition, one or a plurality of hydrogen atoms in (CH ₂ )n forming an alicyclic ring may be substituted with a straight-chain alkyl group such as a methyl group and an ethyl group.

As the epoxy compound, an alicyclic epoxy compound is preferable, and an epoxy cyclohexane (in the above formula (II)) is preferable because it is easy to obtain a protective layer with better adhesion to the polarizer. , n=4), or epoxy cycloheptane (in the above formula (II), n=5) epoxy compound.

In this composition, an epoxy compound may be used individually by 1 type, and may use 2 or more types together.

(radical polymerization initiator)

When the present composition contains the above-mentioned radically polymerizable compound, it is preferable to further contain a radical polymerization initiator. The radical polymerization initiator may be one that can initiate polymerization of radically polymerizable compounds such as (meth)acrylic compounds by irradiating active energy rays, and well-known ones can be used.

酮、茀酮、樟腦醌、苯甲醛、蒽醌等。 As a radical polymerization initiator, for example, acetophenone, 3-methylacetophenone, benzyldimethylketal, 1-(4-isopropylphenyl)-2-hydroxy- 2-Methylpropan-1-one, 2-methyl-1-[4-(methylthio)phenyl-2-morpholinopropan-1-one and 2-hydroxy-2-methyl-1- Acetophenone-based starter of phenylpropan-1-one; such as benzophenone, 4-chlorobenzophenone and 4,4'-diaminobenzophenone benzoin ether-based initiators such as benzoin propyl ether and benzoin ethyl ether; thioxanthone-based initiators such as 4-isopropyl thioxanthone; and

ketone, fenone, camphorquinone, benzaldehyde, anthraquinone, etc.

Radical polymerization initiators can be easily obtained as commercial products, for example, "IRGACURE (registered trademark) 184", "IRGACURE (registered trademark) 907", and "DAROCUR (registered trademark) manufactured by BASF Corporation are each listed by their trade names. )1173", "Lucirin (registered trademark) TPO", etc.

In the present composition, the radical polymerization initiators may be used alone or in combination of two or more.

(cationic polymerization initiator)

When the present composition contains a cationically polymerizable compound such as the above-mentioned oxetane compound and the above-mentioned epoxy compound, it is preferable to further contain a cationic polymerization initiator. The cationic polymerization initiator can generate a cationic species or a Lewis acid by irradiating active energy rays such as visible rays, ultraviolet rays, X rays, and electron rays, and start the polymerization reaction of the cationically polymerizable compound. Examples of the cationic polymerization initiator include onium salts such as aromatic diazonium salts, aromatic iodonium salts, and aromatic peronium salts, iron-aromatic complexes, and the like.

As an aromatic diazonium salt, a benzodiazonium hexafluoroantimonate, a benzodiazonium hexafluorophosphate, a benzodiazonium hexafluoroborate, etc. are mentioned, for example.

As the aromatic iodonium salt, for example, diphenyliodonium (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, bis( 4-nonylphenyl) iodonium hexafluorophosphate, etc.

Examples of the aromatic perylene salt include triphenyl perylene hexafluorophosphate, triphenyl perylene hexafluoroantimonate, triphenyl perylene (pentafluorophenyl) borate, 4,4'-bis [Diphenylperyl]diphenylsulfide bishexafluorophosphate, 4,4'-bis[bis(β-hydroxyethoxy)phenylperyl]diphenylsulfide bishexafluoroantimonate , 4,4'-bis[bis(β-hydroxyethoxy)phenyl peryl]diphenyl sulfide bishexafluorophosphate, 7-[bis(p-tolyloxy) peryl]-2- Isopropyl thioxanthone (thioxanthone) hexafluoroantimonate, 7-[bis(p-tolylyl) perionyl]-2-isopropyl thioxanthone (thioxanthone) tetra(pentafluorophenyl) borate , 4-phenylcarbonyl-4'-diphenyl peryl-diphenyl sulfide hexafluorophosphate, 4-(p-tert-butylphenylcarbonyl)-4'-diphenyl peryl-diphenyl thioether hexafluoroantimonate, 4-(p-tert-butylphenylcarbonyl)-4'-bis(p-toluyl) peryl-diphenylsulfide tetra(pentafluorophenyl)borate Wait.

Examples of iron-aromatic complexes include xylene-cyclopentadienyl iron (II) hexafluoroantimonate, cumene-cyclopentadienyl iron (II) hexafluorophosphate, Toluene-cyclopentadienyl iron (II) ginseng (trifluoromethylsulfonyl) methide, etc.

These cationic polymerization initiators are easily available on the market, and for example, "KAYARAD (registered trademark) PCI-220" and "KAYARAD (registered trademark) sold by Nippon Kayaku Co., Ltd., respectively, are listed by their respective trade names. PCI-620", "UVI-6990" sold by Dow Chemical Co., Ltd., "UVACURE (registered trademark) 1590" sold by DAICEL-CYTEC Co., Ltd., "ADEKA OPTOMER (registered trademark) SP sold by ADEKA Co., Ltd. -150" and "ADEKA OPTOMER (registered trademark) SP-170", "CI-5102", "CIT-1370", "CIT-1682", "CIP-1866S", "CIP" sold by Nippon Soda Co., Ltd. -2048S" and "CIP-2064S", "DPI-101", "DPI-102", "DPI-103", "DPI-105", "MPI-103", "MPI" sold by MIDORI Chemical Co., Ltd. -105", "BBI-101", "BBI-102", "BBI-103", "BBI-105", "TPS-101", "TPS-102", "TPS-103", "TPS-105" ", "MDS-103", "MDS-105", "DTS-102" and "DTS-103", "PI-2074" sold by Rhodia, etc.

Among these cationic polymerization initiators, aromatic periconium salts are preferred because they can absorb light having a wavelength of 300 nm or more, have excellent curability, and can obtain cured products having good mechanical strength and adhesion.

The cationic polymerization initiator may be used alone or in combination of two or more.

(other additives)

The present composition may contain, in addition to the above-mentioned compounds, a photosensitizer, a solvent, a leveling agent, an antioxidant, a light stabilizer, an ultraviolet absorber, and the like within the range that does not impair the effects of the present invention.

Examples of photosensitizers that can also be used in the present embodiment include carbonyl compounds, organic sulfur compounds, persulfide compounds, redox compounds, azo compounds, diazo compounds, halogen compounds, and photoreducing dyes. .

As the solvent that can also be used in this embodiment, for example, aliphatic hydrocarbons such as n-hexane and cyclohexane; aromatic hydrocarbons such as toluene and xylene; such as methanol, ethanol, propanol, isopropanol and normal Alcohols such as butanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as methyl acetate, ethyl acetate and butyl acetate; such as methylcellulo Cyrus, ethyl Cyrus and butyl Cyrus; halogenated hydrocarbons such as dichloromethane and chloroform, etc.

Various compounds such as polysiloxane-based, fluorine-based, polyether-based, acrylic copolymer-based, and titanate-based compounds can be used as leveling agents that can also be used in the present embodiment.

As an antioxidant which can also be used in this embodiment, for example, the primary antioxidant of a phenol type and an amine type, a sulfur type secondary antioxidant, etc. are mentioned.

As a light stabilizer which can also be used in this embodiment, hindered amine light stabilizer (HALS) etc. are mentioned.

As an ultraviolet absorber which can also be used in this embodiment, a benzophenone type, a benzotriazole type, a benzoate type, etc. are mentioned.

[protective film]

FIG. 2 is a schematic cross-sectional view showing a modification of the layer structure of the laminated film of the present embodiment. As shown in FIG. 2 , in the laminated film 2 , a protective film 23 can be further laminated on the side opposite to the side where the polarizer layer 11 and the resin layer 21 are laminated. As a material for forming the protective film 23, the same resin as the material for forming the resin layer 21 described above can be used. The material for forming the resin layer 21 and the material for forming the protective film 23 may be the same or different.

The protective film 23 is laminated on the polarizer layer 11 through the adhesive layer 33 .

Examples of the adhesive layer 33 include water-based adhesives and active energy ray-curable adhesives, and examples of active energy ray-curable adhesives include cationic polymerization-based active-energy-ray-curable adhesives and radical polymerization-based adhesives. Energy ray hardening adhesive. In addition, a pressure-sensitive adhesive layer may be provided instead of the adhesive layer 33 . As an adhesive layer, the adhesive containing an acrylic resin is mentioned.

An adhesive layer (not shown) may be provided on the opposite side of the polarizer layer 11 and the resin layer 21, or on the opposite side of the protective film on which the polarizer layer 11 is laminated. By providing the adhesive layer, the laminated film 2 can be bonded to the liquid crystal cell of the display device. As an adhesive layer, the adhesive containing an acrylic resin is mentioned. The laminated film of the present invention is preferably arranged on the viewing side of a liquid crystal cell.

[Manufacturing method of laminated film]

The laminated film 1 of the present embodiment includes the following steps: (i) forming an adhesive composition layer containing a compound having at least one (meth)acryloyl group in the molecule on one side of the resin layer 21 having a slow axis (hereinafter referred to as "adhesive composition layer") step; (ii) the polarizer layer 11 and the above-mentioned (i) adhesive composition layer formed with the resin layer 21, the slow axis of the resin layer 21 is aligned The steps of laminating the polarizer layer 11 in such a way that the absorption axis of the polarizer layer 11 becomes 45±10° or 135±10° to obtain a laminate having the polarizer layer 11 , the adhesive composition layer and the resin layer 21 laminated in this order; and ( iii) A step of obtaining the adhesive layer 31 by irradiating the laminate obtained in the above (ii) with active energy rays (eg, ultraviolet rays, visible light, electron rays, X-rays, etc.) to harden the adhesive composition layer. Hereinafter, each step will be described with a specific example.

In the step shown in the above (i), first, the resin layer 21 having the slow axis is prepared. When the polarizer layer 11 is continuously produced, there is a case where the elongated polarizer layer has an absorption axis in the flow direction. From the viewpoint of being able to manufacture a laminated body (laminated film) by a roll-to-roll method, and from the viewpoint of being able to arrange both so that the angle formed between the absorption axis and the slow axis of the resin layer 21 falls within the above-mentioned range, the resin The layer 21 is preferably manufactured by extending diagonally.

As a stretching machine used for diagonal stretching, for example, a tenter-type stretching machine is mentioned. The tenter-type stretching machine can apply a feed force, a stretching force or a pulling force at different speeds on the left and right sides, in the transverse direction or in the longitudinal direction or in both directions. As such a tenter-type stretching machine, a horizontal uniaxial stretching machine, a simultaneous biaxial stretching machine, etc. are mentioned, and any appropriate stretching machine can be used as long as the resin film can be continuously diagonally stretched.

As a method of forming an adhesive composition layer on one surface of the resin layer 21, a method of directly applying the present composition and drying as necessary can be mentioned. Moreover, as another method, after apply|coating this composition to a transparent base material film and drying as needed, the method of transcribe|transferring this coating layer to the polarizer layer 11 is mentioned. In the latter case, the base film is removed before the step shown in the above (ii). The transparent base film system can use the same resin as the above. In addition, in the transparent base film, the coating surface of this composition may be subjected to a peeling treatment in advance.

As a coating method of this composition, a well-known coating method can be employ|adopted, for example, a doctor blade, a wire bar, a die coater, a comma coater, a gravure coater, etc. are mentioned.

In the step shown in the above (ii), the polarizer layer 11 and the adhesive composition layer with the resin layer 21 formed in the above (i) can be laminated to obtain the polarizer layer 11 and the adhesive composition layered in sequence. A laminate of the material layer and the resin layer 21.

In the step shown in the above (iii), the layered product obtained in the above (ii) is irradiated with active energy rays such as visible rays, ultraviolet rays, X rays, or electron rays to harden the adhesive composition layer into an adhesive layer. The agent layer 31 is formed to obtain the laminated film 1 .

The light source system used for irradiating the active energy rays is not particularly limited, and a light source having a light emission distribution at a wavelength of 400 nm or less can be used. Examples of such a light source include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and metal halide lamps.

The irradiation intensity of active energy rays varies depending on the adhesive composition to be cured, and the irradiation intensity in the wavelength region effective for activation of the cationic polymerization initiator is preferably set in the range of 10 to 2500 mW/cm ² .

The irradiation time of the active energy ray varies depending on the adhesive composition to be cured, and the cumulative light amount represented by the product of the irradiation intensity and the irradiation time is preferably set in the range of 10 to 2500 mJ/cm ² .

In addition, in the above-mentioned production example, the adhesive composition layer is formed on one side of the resin layer 21, but it may be formed on one side of the polarizer layer 11, or may be formed on both sides. As shown in FIG. 2 , on the opposite side of the polarizer layer 11 to which the resin layer 21 is attached, a protective film 23 may be laminated, or an adhesive layer (not shown in the figure) may be provided for attaching to the liquid crystal cell. Show).

According to the laminated film having the above-mentioned constitution, a high degree of polarization can be maintained even in a humid and hot environment.

<Laminated film blank>

In this embodiment, both the polarizer layer and the resin layer may be elongated. The laminated film base film (long-shaped laminated film) of the present embodiment has a strip-shaped polarizing film base film (long-shaped polarizer layer); a strip-shaped resin film base film (long-shaped resin layer); and the polarizing film The base film and the resin film base film are bonded to the adhesive layer.

The polarizing film blank film is a tape-shaped film using a PVA-based resin as a forming material, and a dichroic dye is oriented in the longitudinal axis direction of the film. The PVA-based resin and the dichroic dye are the same as above.

The resin film blank film is formed by extending a tape-shaped film with a thermoplastic resin and a plasticizer as forming materials in an oblique direction with respect to the longitudinal axis direction of the film. Thereby, the roll-to-roll method can be adopted when laminating with the polarizing film blank film, and the manufacturing process can be simplified. The thermoplastic resin and the plasticizer are the same as those described above.

The resin film blank film is preferably a retardation film blank film. The resin film base film is provided with a slow axis at an arbitrary angle with respect to the absorption axis of the above-mentioned polarizing film base film. The arbitrary angle is, for example, preferably 45±10° or 135±10° with respect to the absorption axis of the above-mentioned polarizing film blank. By setting the angle of the slow axis in the above-mentioned range, when the laminated film blank of the present embodiment is applied to a display device, even when viewed through a polarizing glass, a configuration having excellent visibility can be achieved.

The adhesive layer contains, as a forming material, a cured product of an adhesive composition, and the adhesive composition contains a compound having at least one (meth)acryloyl group in the molecule. The compound which has at least 1 (meth)acryloyl group in a molecule|numerator is the same as above. It is recognized that compounds having at least one (meth)acryloyl group in the molecule, in addition to the above-mentioned low affinity with plasticizers, form a cross-linked structure during polymerization, so plasticizers are less likely to invade and contain the A hardened product of a composition of compounds. Therefore, it can be presumed that in a humid and hot environment (for example, an environment of room temperature of 60°C and humidity of 95%), even when the plasticizer migrates from the resin film blank to the polarizing film blank, the intrusion of the plasticizer can be suppressed.

When the laminated film blank having the above-mentioned constitution is used, a high degree of polarization can be maintained even in a humid and hot environment.

[Example]

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to these examples. The unstretched film used in this embodiment refers to a film in an unstretched state.

[Evaluation of moisture and heat resistance of laminated films]

The laminated films of Examples and Comparative Examples were left to stand for 250 hours in an environment with a temperature of 65° C. and a relative humidity of 90%, and the visual sensitivity correction polarization degree before and after the stand was compared. At this time, the absolute value (ΔPy) of the value obtained by subtracting the visual sensitivity-corrected polarization degree before standing after being left alone was 0.3 or less was rated as ○, and those with ΔPy greater than 0.3 were rated as ×. In addition, the viewing sensitivity correction polarization degree was measured using the following method. The results are shown in Tables 1 to 3.

(Measurement of Sensitivity Correction Polarization Degree)

The MD transmittance and TD transmittance in the wavelength range of 380nm - 780nm were measured about the laminated film of an Example and a comparative example using the spectrophotometer (manufactured by JASCO Corporation, "V7100") with an integrating sphere. Next, the degree of polarization at each wavelength is calculated based on (T1) using the MD transmittance and the TD transmittance.

Here, the "MD transmittance" means the transmittance when the polarization direction from the Glan-Thomson plane is parallel to the transmission axis of the laminated film sample. In addition, the "TD transmittance" refers to the transmittance when the polarization direction from the Glan-Thomson plane is perpendicular to the transmission axis of the laminated film sample.

(Measurement of the moisture permeability of the evaluation sample)

Evaluation samples were prepared in the following manner. First, the adhesive composition is applied on a cellulose triacetate film using a rod coater so that the thickness may be about 2 to 3 μm to form an adhesive composition layer. As the cellulose triacetate film for measuring the moisture permeability of the evaluation sample, a value calculated by the cup method (JIS Z 0208, temperature 40°C, humidity 90% RH) was used with a thickness of 57.5 μm and a moisture permeability. ) is KC6UA manufactured by Konica Minolta Co., Ltd. at 553 g/m ² ‧24 hours. Next, from the adhesive composition layer side, using "D Bulb" manufactured by Fusionv UV Systems, ultraviolet rays were irradiated so that the cumulative light intensity was 400 mJ/cm ² , and the adhesive composition layer was cured to serve as an evaluation sample. The moisture permeability cup method of the obtained evaluation sample was measured by the cup method (JIS Z 0208, temperature 40°C, humidity 90% RH).

[Production Example (Preparation of Adhesive Composition)]

According to the compounding amounts shown in Tables 1 to 3, the adhesive compositions of Examples and Comparative Examples were prepared, respectively. However, the names of the compounds used for preparation may be represented by abbreviations.

In addition, the cationic polymerization initiator "ADEKA OPTOMER (registered trademark) SP-150" used the propylene carbonate solution, and Table 1 shows the amount of the active ingredient. In addition, the epoxy-based crosslinking agent "Sumirez Resin (registered trademark) 650" is an aqueous solution, and Table 2 shows the active ingredient amount.

In addition, the following compounds were used for each component of the adhesive composition.

[Active energy ray curable adhesive composition] (cationic polymerizable compound)

"CELLOXIDE (registered trademark) 2021P": 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, available from Daicel Chemical Co., Ltd.

"YX8000": Diglycidyl ether of bisphenol, purchased from Mitsubishi Chemical Corporation.

"ARON OXETANE (registered trademark) OXT-101": 3-ethyl-3-hydroxymethyl oxetane, available from Toagosei Co., Ltd.

Among the above-mentioned cationically polymerizable compounds, the structure of the oxetane compound is represented by the following formula (IV).

(radical polymerizable compound)

"DMAA": Dimethacrylamido group, purchased from KJ Chemicals Co., Ltd.

"4HBA": 4-hydroxybutyl acrylate, available from Nippon Kasei Co., Ltd.

"UV-3700B": urethane acrylate, purchased from Nippon Synthetic Chemical Industry Co., Ltd.

"CHDMMA": 1,4-cyclohexanedimethanol monoacrylate, available from Nippon Kasei Co., Ltd.

"A-DCP": Tricyclodecane dimethanol diacrylate, purchased from Shin-Nakamura Chemical Industry Co., Ltd.

(cationic polymerization initiator)

"ADEKA OPTOMER (registered trademark) SP-150": 4,4'-bis[diphenylperionyl]diphenyl sulfide bishexafluorophosphate-based photocationic polymerization initiator, in the form of an acrylic carbonate solution Purchased from ADEKA Co., Ltd.

(radical polymerization initiator)

"DAROCUR (registered trademark) 1173": 2-hydroxy-2-methyl-1-phenyl-propan-1-one, available from BASF Japan Co., Ltd.

"IRGACURE (registered trademark) 907": 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, available from BASF JAPAN Co., Ltd.

[Water-based adhesive composition] (polyvinyl alcohol)

"KURARAY POVAL (registered trademark) KL-318": Carboxyl group-modified polyvinyl alcohol, available from KURARAY Co., Ltd.

(Epoxy based crosslinking agent)

"Sumirez Resin (registered trademark) 650": water-soluble polyamide epoxy resin (aqueous solution with a solid content concentration of 30%), purchased from Sumika Chemtex Co., Ltd.

[other ingredients]

"SH710": Silicone leveling agent, purchased from TORAY. DOW CORNING Co., Ltd.

[Examples 1 to 5, Comparative Examples 1 to 6] (a) Manufacture of polarizer layer

A polyvinyl alcohol film with an average degree of polymerization of about 2400, a degree of saponification of 99.9 mol% or more, and a thickness of 30 μm was subjected to dry uniaxial stretching to about 5 times, and immersed in pure water 1 at 60°C in a state of tension. Minutes later, it was immersed for 60 seconds at 28 degreeC in the aqueous solution of the weight ratio of iodine/potassium iodide/water of 0.05/5/100. Subsequently, it was immersed in an aqueous solution of potassium iodide/boric acid/water in a weight ratio of 8.5/8.5/100 at 72°C for 300 seconds. Next, after washing with pure water at 26° C. for 20 seconds, drying was performed at 65° C. to produce a polarizer layer in which iodine was aligned on the polyvinyl alcohol film after uniaxial stretching. The thickness of the polarizer was 12 μm.

(b) Preparation of resin layer

A plasticizer-containing cellulose triacetate film produced by diagonal stretching was prepared as a resin layer. One surface of this cellulose triacetate film is formed with a hard coat layer. In addition, the angle of the slow axis with respect to the longitudinal axis direction of the resin layer was about 45° on average.

The following materials were used as the cellulose triacetate film system produced by diagonal stretching.

Cellulose triacetate film produced by oblique stretching: Konica Minolta Co., Ltd., KC4UGR-HC, thickness=44 μm, _Re (590)=106 nm, R _th (590)=75 nm, R _th (590 )/R _e (590)=0.71, R _e (450)/R _e (550)=0.96, R _e (630)/R _e (550)=1.02)

In addition, _Re (590), _Re (450), _Re (550), and _Re (630) represent in-plane retardation values at measurement wavelengths of 590 nm, 450 nm, 550 nm, and 630 nm, respectively, and R _th (590) It shows the retardation value in the thickness direction at the measurement wavelength of 590 nm.

(c) Production of Laminated Films

Next, the adhesive composition obtained in the production example was applied to the surface of the resin layer (b) on which the hard coat layer was not formed to form an adhesive composition layer. Specifically, the adhesive composition was applied using a rod coater (manufactured by Daiichi Rika Co., Ltd.) so that the film thickness after curing was about 2 µm. Further, a corona discharge treatment was performed on one side of an unstretched film of norbornene-based resin having a thickness of 23 μm [trade name “ZEONOR (registered trademark)” by ZEON Co., Ltd.]. The said adhesive composition was apply|coated to this corona discharge-treated surface similarly to a resin layer, and the adhesive composition layer was formed. In addition, the unstretched film is the raw material of the protective film in the laminated film.

One surface of the polarizer layer produced in the above (a) was bonded to the resin layer, and the other surface of the polarizer layer was bonded to the adhesive composition layer on which the unstretched film was formed to produce a laminate. For the lamination system, an attachment device (manufactured by Fujipla Co., Ltd., "LPA3301") was used. At the time of bonding, the formation angle of the absorption axis of the polarizer layer and the slow axis of the resin layer was set to 45°.

Next, ultraviolet rays were irradiated from the non-stretched film side of the obtained laminate so that the cumulative light intensity was 250 mJ/cm ² using an ultraviolet irradiation device with a conveyor belt [the lamp system used "D Bulb" manufactured by Fusionv UV Systems Co., Ltd.] to harden the adhesive composition layer. In this way, a laminated film including a protective film/polarizer layer/adhesive layer/resin layer/hard coat layer is produced.

The moisture permeability of the evaluation samples obtained from the adhesive compositions used in the respective Examples and Comparative Examples is as follows.

Example 3: 297g/m ² . 24hr, Example 5: 251g/m ² . 24hr, Comparative Example 1: 447g/m ² . 24hr, Comparative Example 3: 307g/m ² . 24hr, Comparative Example 4: 428g/m ² . 24hr, Comparative Example 5: 529g/m ² . 24hr

[Comparative Example 7]

(c) In the production of the laminated film, the laminated film of Comparative Example 7 was produced in the same manner as in Example 1 except that the following operations were performed.

The resin layer prepared in the above (b) was bonded to one side of the polarizer layer produced in the above (a) via the water-based adhesive composition obtained in the production example. Then, after drying at 80 degreeC for 5 minutes, ageing was performed at 40 degreeC and 23%RH for 72 hours, and the laminated|multilayer film was manufactured.

[Reference example] (a-1) Production of polarizer layer

A polarizer layer with a thickness of 30 μm in which iodine was aligned on the polyvinyl alcohol film after uniaxial stretching was produced.

(b-1) Preparation of resin layer

A cellulose triacetate film (KC4FR-1, manufactured by Konica Minolta Opto Co., Ltd.) having a thickness of 43 μm was prepared by saponification. The film is a stretch film and contains a plasticizer.

(b-2) Preparation of protective film

Prepare a saponification treatment for the hard-coated cellulose triacetate film. The thickness of the film was 83 μm.

(c-1) Production of Laminated Film

The resin layer prepared in (b-1) was bonded to one side of the polarizer layer produced in (a-1) above through a nip roll through the water-based adhesive composition obtained in the above production example, and the same adhesive was passed through. Composition The protective film prepared in (b-2) was bonded to the other side to produce a laminate. At this time, the slow axis of the resin layer and the absorption axis of the polarizer layer were made substantially parallel. When bonding the protective film prepared in (b-2), the side without the hard coat layer is the bonding surface with the polarizer layer. Next, the laminate was passed through a drying furnace while maintaining the tension, and the adhesive was dried to obtain a laminate film.

An adhesive layer (thickness 15 μm) having a storage elastic modulus of about 0.7 MPa was provided on the opposite side of the resin layer and the polarizer layer. Through this adhesive layer, the laminated film was bonded to the glass, and the sample was evaluated. The sample was left in an environment with a temperature of 65° C. and a relative humidity of 90% for 250 hours in the same manner as in the above-mentioned evaluation of the heat and humidity resistance, and the sensitivity-corrected polarization degree before and after being left was compared. As a result, the change amount ΔPy of the correction polarization degree of visibility was 0.3% or less.

The results from Tables 1 to 3 show that when an adhesive composition containing a compound having at least one (meth)acryloyl group in the molecule is used, even if ΔPy is 0.3 or less, the adhesive composition can be kept high in a humid heat environment degree of polarization.

From the above, it can be confirmed that the present invention is useful.

[Industrial Availability]

The present invention can be utilized as a polarized light supply element or a polarized light detection element in a display device such as a liquid crystal display device.

1‧‧‧Laminated film

11‧‧‧Polarizer layer

21‧‧‧Resin layer

31‧‧‧Adhesive layer

Claims (2)

A laminated film comprising: a polarizer layer in which a dichroic pigment is aligned in a polyvinyl alcohol-based resin; A forming material; and an adhesive layer, which is a bonding agent of the polarizer layer and the resin layer; wherein, the resin layer contains a plasticizer, the adhesive layer contains a cured product of an adhesive composition as a forming material, and the adhesive The adhesive composition contains a compound having at least one (meth)acryloyl group in the molecule, and the adhesive composition is coated on a cellulose triacetate film with a thickness of 2 to 3 μm and hardened. The water vapor transmission rate of the evaluation sample calculated by the cup method is 300g/m ² ·24 hours or less, wherein the cup method is implemented according to JIS Z 0208 at a temperature of 40°C and a humidity of 90%RH. The laminated film according to claim 1, wherein the polarizer layer and the resin layer are both elongated.

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