TW201641632A - Curable adhesive composition for polarizing films, polarizing film and method for producing same, optical film, and image display device - Google Patents

Abstract

A curable adhesive composition for polarizing films, which is used for the purpose of bonding a transparent protection film to at least one surface of a polarizer, and which is characterized by containing an active energy ray-curable component and at least one organic metal compound that is selected from the group consisting of metal alkoxides and metal chelates. It is preferable that the metal of the organic metal compound is titanium. It is also preferable that a metal alkoxide is contained as the organic metal compound and the metal alkoxide has an organic group that has 6 or more carbon atoms. It is also preferable that a metal chelate is contained as the organic metal compound and the metal chelate has an organic group that has 4 or more carbon atoms.

Description

Curable adhesive composition for polarizing film, polarizing film, manufacturing method thereof, optical film, and image display device Field of invention

The present invention relates to a curable adhesive composition for a polarizing film for forming the above-mentioned adhesive layer in a polarizing film obtained by laminating a polarizer and a transparent protective film with an adhesive. Further, the present invention relates to a polarizing film using the above-mentioned adhesive layer. The polarizing film may be formed of an optical film alone or in layers to form an image display device such as a liquid crystal display (LCD), an organic EL display device, a CRT, or a PDP.

Background of the invention

Liquid crystal display devices such as clocks, mobile phones, PDAs, notebook computers, computer monitors, DVD players, and TVs have rapidly expanded in the market. The liquid crystal display device visualizes the polarization state by switching of the liquid crystal, and it is known from the display principle that a polarizer is used. In particular, in the use of TVs and the like, the pursuit of high brightness, high contrast, and wide viewing angle is the pursuit of high transmittance, high degree of polarization, high color reproducibility, and the like of the polarizing film.

As the polarizing member, from the viewpoint of having high transmittance and high degree of polarization, for example, an iodine-based polarizing member in which polyvinyl alcohol (hereinafter also referred to as "PVA") adsorbs iodine and extends is most widely used. . Generally used The polarizing film is a so-called water-based adhesive which dissolves a polyvinyl alcohol-based material in water, and a transparent protective film is bonded to both surfaces of the polarizing material (Patent Document 1 below). The transparent protective film is made of triacetin cellulose or the like having high moisture permeability. When the water-based adhesive (so-called wet laminate) is used, a drying step is required after the polarizer is bonded to the transparent protective film.

On the other hand, in place of the water-based adhesive, an active energy ray-curable adhesive has been proposed. When a polarizing film is produced using an active energy ray-curable adhesive, the productivity of the polarizing film can be improved because a drying step is not required. For example, a radical polymerization type active energy ray-curable adhesive composition using an N-substituted amide-based monomer as a curable component has been proposed (Patent Document 2 below). The adhesive composition can exhibit excellent durability in a severe environment under high humidity and high temperature, but in fact, there is still a need in the market for an adhesive composition which further improves adhesion and/or water resistance.

Advanced technical literature Patent literature

Patent Document: Japanese Patent Laid-Open No. 2006-220732

Patent Document 2: Japanese Patent Laid-Open No. 2008-287207

Summary of invention

The present invention has been made in view of the above circumstances, and an object of the invention is to provide a cured adhesive composition for a polarizing film which can form a good adhesion between a polarizing member and a transparent protective film and under severe conditions such as a dew condensation environment. An adhesive layer that still has excellent water resistance.

Further, an object of the present invention is to provide a polarizing film which is provided with a transparent protective film on a polarizing member by using an adhesive layer formed of a hardening type adhesive composition using a polarizing film; and further provides a polarizing film using the foregoing The optical film further provides an image display device using the polarizing film or the optical film.

As a result of intensive studies to solve the above problems, the present inventors have found that the above object can be attained by the following composition for a curing adhesive for a polarizing film, and the present invention has been completed.

That is, the present invention relates to a hardenable adhesive composition for a polarizing film for adhering a transparent protective film to at least one side of a polarizing member; characterized by comprising an active energy ray hardening component, and being selected from a metal alkane At least one organometallic compound in the group consisting of an oxide and a metal chelate.

In the hardenable adhesive composition for a polarizing film, the metal of the organometallic compound is preferably titanium.

In the cured adhesive composition for a polarizing film, the organometallic compound preferably contains the metal alkoxide, and the organic alkoxide of the metal alkoxide preferably has 6 or more carbon atoms; and the organometallic compound The metal chelate compound is preferably contained, and the carbon number of the metal chelate compound is preferably 4 or more.

In the cured adhesive composition for a polarizing film, when the total amount of the active energy ray-curable components is 100 parts by weight, the above-mentioned The ratio of the organic metal compound is preferably 0.05 to 9 parts by weight.

In the hardenable adhesive composition for a polarizing film, when the cured product obtained by curing the curable adhesive composition is immersed in pure water at 23 ° C for 24 hours, the bulk water absorption ratio represented by the following formula is preferably 10% by weight or less: Formula: {(M2-M1)/M1}×100 (%)

At this time, M1: weight of the cured product before impregnation; M2: weight of the cured product after impregnation.

In the cured adhesive composition for a polarizing film, the active energy ray-curable component preferably contains a radical polymerizable compound, and the radical polymerizable compound preferably contains a (meth) acrylamide derivative, and the radical polymerization is carried out. The compound preferably contains a polyfunctional compound having at least two radically polymerizable functional groups.

The curable adhesive composition for a polarizing film preferably contains a photopolymerization initiator, and further preferably contains a vinyl ether group-containing compound, and further contains a photoacid generator.

In the cured adhesive composition for a polarizing film, it is preferred that the cured resin composition obtained by curing the curable adhesive composition has a storage elastic modulus at 25 ° C of 1 × 10 ⁷ Pa or more.

Furthermore, the present invention relates to a polarizing film provided with a transparent protective film on at least one side of a polarizing member, wherein the adhesive layer is hardened by a polarizing film according to any one of items 1 to 11. A cured layer of a type of adhesive composition is formed. The thickness of the above adhesive layer is preferably 0.1 to 3 μm. In addition, the foregoing adhesive layer is impregnated in pure water at 23 ° C. In the case of 24 hours, the overall water absorption ratio expressed by the following formula is preferably 10% by weight or less: Formula: {(M2-M1)/M1}×100 (%)

At this time, M1: the weight of the cured product before impregnation; M2: the weight of the cured product after the immersion; and the storage elastic modulus of the above-mentioned adhesive layer at 25 ° C is preferably 1.0 × 10 ⁷ Pa or more.

Further, the present invention relates to a method for producing a polarizing film according to the present invention, comprising the step of: applying a curing step of applying the polarizing film to at least one surface of the polarizer and the transparent protective film; And a bonding step of bonding the polarizing member and the transparent protective film; and, in the following step, irradiating the side of the polarizing member or the side of the transparent protective film surface with an active energy ray to harden the active energy ray The type of the adhesive composition is cured to obtain the adhesive layer, and the polarizer and the transparent protective film are passed through the adhesive layer.

Further, the present invention relates to an optical film characterized in that at least one of the above-described polarizing films is laminated, and an image display device characterized by using the above-described polarizing film or the optical film described above.

When the polarizing film in which the transparent protective film is laminated on the polarizer through the adhesive layer is exposed to a dew condensation environment, it can be presumed that the mechanism of the subsequent peeling between the adhesive layer and the polarizing member is as follows. First, penetrate The moisture of the protective film diffuses in the adhesive layer, and the moisture diffuses to the interface side of the polarizer. Here, in the case of the conventional polarizing film, the hydrogen bonding and/or the ionic bonding contributes a large amount to the adhesion between the adhesive layer and the polarizing member, but the moisture diffused to the interface side of the polarizing member causes the hydrogen on the interface. The bond and the ionic bond dissociate, resulting in a decrease in the adhesion of the adhesive layer to the polarizer. Therefore, in the dew condensation environment, there is a case where peeling occurs between the adhesive layer and the polarizer.

On the other hand, the curable adhesive composition for a polarizing film of the present invention contains at least one organometallic compound selected from the group consisting of metal alkoxides and metal chelate compounds. The organometallic compound becomes an active metal species by interfering with moisture, and as a result, the organometallic compound strongly interacts with both the polarizer and the active energy ray-curable component constituting the adhesive layer. Thereby, even if moisture exists at the interface between the polarizer and the adhesive layer, and the organic metal compound strongly interacts with each other, the subsequent water resistance between the polarizer and the adhesive layer is drastically improved.

In the cured adhesive composition for a polarizing film of the present invention, the cured water-absorbent composition is cured to obtain a total water absorption of the cured product of preferably 10% by weight or less. The overall water absorption rate shows that the water repellency is extremely low when the adhesive layer obtained by using the cured adhesive composition for a polarizing film of the present invention forms an adhesive layer. Therefore, a polarizing film of a transparent protective film is provided on the adhesive layer formed by the polarizer passing through the cured layer, and the polarizer and the transparent protective film layer have good adhesion and are in a harsh environment under high temperature and high humidity. Optical durability can meet higher levels.

For example, there is a hardened type with a polarizing film using the present invention. The polarizing film of the cured layer (adhesive layer) formed of the agent composition is also excellent in optical durability (humidification durability test) under a severe humidification environment (for example, 85 ° C × 85% RH). Therefore, the polarizing film of the present invention can lower the transmittance of the polarizing film and control the decrease (change) of the degree of polarization even if it is in the aforementioned harsh humidification environment. Further, the polarizing film of the present invention can suppress the reduction of the adhesion even in a severe environment such as immersion in water, and even between the polarizing member and the transparent protective film even under severe conditions of contact with water. The magnitude of the decrease in the adhesion force (between the polarizer and the adhesive layer) is depressed.

Form for implementing the invention

The curable adhesive composition for a polarizing film of the present invention contains an active energy ray-curable component and at least one organometallic compound selected from the group consisting of a metal alkoxide and a metal chelate.

<selected from at least one organometallic compound selected from the group consisting of metal alkoxides and metal chelate compounds>

The metal alkoxide is a compound in which at least one alkoxy group as an organic group is bonded to a metal, and the metal chelate compound is a compound in which an organic group is bonded or coordinated to a metal via an oxygen atom. As the metal, titanium, aluminum, and zirconium are preferred. Among them, the reactivity of aluminum and zirconium is faster than that of titanium, and the life of the adhesive composition is shortened, and the effect of improving the water resistance is lowered. Therefore, from the viewpoint of improving the subsequent water resistance of the adhesive layer, the metal as the organometallic compound is preferably titanium.

When the hardenable adhesive composition for a polarizing film of the present invention contains a metal alkoxide as the organometallic compound, it is preferred to use a metal alkoxide having an organic group having 4 or more carbon atoms, preferably 6 or more. By. When the carbon number is 3 or less, the life of the adhesive composition becomes short, and the effect of improving the water resistance is lowered. The organic group having 6 or more carbon atoms may, for example, be an octyloxy group, and is suitably used. Suitable metal alkoxides include, for example, tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer, tetraoctyl titanate, and tertiary pentyl titanate. , tetra-terternary butyl titanate, tetrastearyl phthalocyanate, tetraisopropoxy zirconium, tetra-n-butoxy zirconium, tetraoctyloxy zirconium, tetra-tertiary butoxy zirconium, tetrapropoxy Zirconium, aluminum butoxide, aluminum ethoxide, aluminum isopropoxide, aluminum butoxide, single- and second-butanol of aluminum isopropoxide, aluminum single-stage butoxy-diisopropylate, and the like. Among them, tetraoctyl titanate is preferred.

When the hardenable adhesive composition for a polarizing film of the present invention contains a metal chelate compound as the organometallic compound, it is preferred to use a metal chelate compound having a carbon number of 4 or more. When the carbon number is 3 or less, the life of the adhesive composition becomes short, and the effect of improving the water resistance is lowered. Examples of the organic group having 4 or more carbon atoms include an acetoacetone group, an ethyl acetoacetate group, an isostearate group, and an octene glycol group. Among them, from the viewpoint of improving the subsequent water resistance of the adhesive layer, the organic group is preferably an acetonitrile or ethyl acetoacetate group. Suitable metal chelate compounds are, for example, titanium acesulfate, titanium octene glycolate, titanium tetraacetone, titanium acetate, titanium hydroxystearate, dipropoxy-bis ( Acetylacetone) titanium, dibutoxy titanium-bis(octene glycol ester), dipropoxy titanium - bis(ethylacetamidineacetic acid), titanium lactate, titanium diethanolamine, titanium triethanolamine, titanium dipropoxide-bis(lactic acid), titanium dipropoxide-bis(triethanolamine), di-n-butoxy Titanium-bis(triethanolamine), tri-n-butoxytitanium monostearate, diisopropoxy bis(ethylacetamidineacetic acid) titanium, diisopropoxy bis (acetamidineacetic acid) Titanium, diisopropoxy ‧ bis(acetonitrile) titanium, titanium phosphate compound, titanium ammonium lactate, titanium-1,3-propanedioxybis(ethylacetamidineacetic acid), dodecylbenzenesulfonate Titanium acid compound, titanium aminoethylethanolamine, zirconium tetraethoxide, zirconium monoacetone acetone, zirconium diacetone acetone, zirconium acetonide diethyl acetoacetate, zirconium acetate, tri-n-butoxy Zirconium acetate, zirconium di-n-butoxy bis(ethylacetamidineacetate), zirconium n-butoxy oxy (ethyl acetoacetate), zirconium tetrakis (n-propyl acetonitrile), Tetrakis(ethethyleneacetate)zirconium, zirconium tetrakis(ethylacetamidineacetate), aluminum ethyl acetoacetate, aluminum acetoacetate, acetamidineacetone, diethyl acetoacetate, diisopropoxy Aluminum acetate, aluminum diisopropoxide, aluminum acetonide, isopropoxy bis (ethyl acetonitrile) Acid) aluminum, isopropoxy bis(acetamidineacetone) aluminum, ginseng (ethyl acetoacetate) aluminum, ginseng (acetonitrile) aluminum, monoethyl acetonide ‧ bis (ethyl acetonitrile) aluminum. Among them, titanium acetacetate and titanium ethyl acetate are preferred.

The organometallic compound which can be used in the present invention may, in addition to the above, be an organic carboxylic acid metal salt such as zinc octoate, zinc dodecanoate, zinc stearate or tin octylate; acetonitrile zinc chelate and benzene. A zinc chelate compound such as a zinc thioglycolate chelate compound, a zinc benzalkonium methane chelate compound, or an ethyl zinc chelate acetate.

In the present invention, the content of the organometallic compound is preferably in the range of 0.05 to 9 parts by weight, preferably 0.1 to 8 parts by weight, based on 100 parts by weight of the total amount of the active energy ray-curable component, and is 0.15 to 5 parts by weight. The serving is preferred. When the amount is more than 9 parts by weight, the storage stability of the adhesive composition is deteriorated, and the ratio of the components to be subsequently applied to the polarizer or the protective film is relatively insufficient and the adhesion is lowered. Further, the effect of the subsequent water resistance when the amount is less than 0.05 part by weight cannot be sufficiently exhibited.

In the present invention, from the viewpoint of improving the liquid stability of the organometallic compound in the composition, the composition may contain an organic metal compound and a polymerizable compound having a polymerizable functional group and a carboxyl group.

<Polymerizable compound having a polymerizable functional group and a carboxyl group>

The polymerizable compound having a polymerizable functional group and a carboxyl group has a polymerizable functional group and a carboxyl group. The polymerizable functional group and the carboxyl group may be one or more than two.

The polymerizable functional group is not particularly limited, and examples thereof include a carbon-carbon double bond-containing group, an epoxy group, an oxetanyl group, and a vinyl ether group.

The polymerizable functional group is preferably a radical polymerizable functional group represented by the following formula (I) or the following formula (II): H ₂ C=C(R ¹ )-COO- (I)

(wherein R ¹ represents hydrogen or an organic group having 1 to 20 carbon atoms; H ₂ C=C(R ² )-R ³ - (II)

(wherein R ¹ represents hydrogen or an organic group having 1 to 20 carbon atoms, and R ³ represents a direct bond or an organic group having 1 to 20 carbon atoms; in particular, R ¹ or R ² is hydrogen or a methyl group; A radical polymerizable functional group is particularly preferred.

The bonding position of the carboxyl group in the polymerizable compound having a polymerizable functional group and a carboxyl group is not particularly limited, but is from the lifted composition. From the viewpoint of the liquid stability of the organometallic compound, the (meth)acrylic acid having a carboxyl group directly bonded to the radical polymerizable functional group is preferably a radical polymerizable functional group having an oxygen-containing carbon number of 1 A radically polymerizable compound in which an organic group of ~20 is bonded to a carboxyl group.

Moreover, from the viewpoint of improving the liquid stability of the organometallic compound in the composition, the polymerizable compound having a polymerizable functional group and a carboxyl group has a large molecular weight, and when bonded and/or coordinated to an organometallic compound, It becomes huge and three-dimensional, and other ligands are better at forming a steric obstacle when they are coordinated. Therefore, the molecular weight of the polymerizable compound having a polymerizable functional group and a carboxyl group is preferably 100 (g/mol) or more, more preferably 125 (g/mol) or more, and particularly preferably 150 (g/mol) or more. The upper limit of the molecular weight of the polymerizable compound having a polymerizable functional group and a carboxyl group is not particularly limited, and is about exemplified in the range of about 300 (g/mol).

Further, from the viewpoint of improving the liquid stability of the organometallic compound in the composition, the polymerizable compound having a polymerizable functional group and a carboxyl group is polymerized by an organic group having an oxygen-containing carbon number of 1 to 20 A polymerizable compound having a functional group and a carboxyl group is preferred. Examples of such an organic group include an alkyl group, an alkenyl group, an alkynyl group, an alkylene group, an alicyclic group, an unsaturated alicyclic group, an alkyl ester group, an aromatic ester group, a decyl group, a hydroxyalkyl group, and an epoxy group. The alkyl group may be bonded individually or in the same organic group, or may be a complex bond of a different organic group. Specific examples of the polymerizable compound (B) include β-carboxyethyl acrylate, carboxypentyl acrylate, β-carboxyethyl methacrylate, 2-propylene methoxyethyl succinic acid, and 2-propenyloxyethyl hexahydrophthalic acid, 2-propenyloxyethyl phthalic acid, ω-carboxy-polycaprolactone monoacrylate, 2- Propylene methoxyethyltetrahydrofurfuric acid, 2-propenyloxypropoxy decanoic acid, 2-propenyloxypropyltetrahydrofurfuric acid, 2-propenyloxypropyl hexahydrophthalic acid, A Acryloxyethyl succinic acid, methacryloxyethyl phthalic acid, methacryloxyethyltetrahydrofurfuric acid, methacryloxyethyl hexahydro phthalic acid, 2-methyl Alkyl propylene oxypropoxy decanoic acid, 2-methyl propylene methoxy propyl tetrahydro phthalic acid, 2-methyl propylene methoxy propyl hexahydro phthalic acid, and the like.

When the total amount of the organometallic compound is α (mol), the polymerizable functional group and the carboxyl group are present in the cured adhesive composition for a polarizing film from the viewpoint of improving the liquid stability of the organometallic compound in the composition. The content of the polymerizable compound is preferably 0.25 α (mol) or more, more preferably 0.35 α (mol) or more, and particularly preferably 0.5 α (mol) or more. When the content of the polymerizable compound having a polymerizable functional group and a carboxyl group is less than 0.25 α (mol), the stability of the organometallic compound is insufficient, and the hydrolysis reaction and the self-condensation reaction proceed, and the service life may be shortened. In addition, the upper limit of the content of the polymerizable compound having a polymerizable functional group and a carboxyl group in the total amount of the organic metal compound α (mol) is not particularly limited, and for example, about 4α (mol) is a exemplified range.

<Composition containing organometallic compounds>

In the cured adhesive composition for a polarizing film of the present invention, when the organometallic compound is used in combination with a polymerizable compound having a polymerizable functional group and a carboxyl group, the active energy ray-curable component, the organometallic compound, and the polymerizable functional group may be used. A material obtained by simultaneously mixing a polymerizable compound having a carboxyl group and a carboxyl group, or a group containing an organometallic compound containing an organometallic compound and a polymerizable compound having a polymerizable functional group and a carboxyl group in advance A substance obtained by mixing it with an active energy ray hardening component.

In the curable adhesive composition for a polarizing film, a carboxyl group having a polymerizable functional group and a carboxyl group-containing polymerizable compound is strongly bonded and/or coordinated with a metal of the organometallic compound, thereby causing an organic metal The compound is stabilized. In this case, when the active energy ray-curable component or the like is not present, the organometallic compound is previously mixed with a polymerizable compound having a polymerizable functional group and a carboxyl group. The reaction rate and/or the coordination ratio of the substances are drastically increased, and the obtained organometallic compound-containing composition contains a high concentration of the organometallic compound and a polymerizable compound having a polymerizable functional group and a carboxyl group. Reactants and/or ligands. Therefore, the obtained organometallic compound-containing composition has extremely high stability of the organometallic compound, and the stability of the organometallic stability of the cured adhesive composition for a polarizing film containing the same is also high.

<hardenable ingredients>

In the curable adhesive composition for a polarizing film of the present invention, an active energy ray-curable component is contained as a curable component.

As the curable component, an active energy ray-curing type such as an electron beam curing type, an ultraviolet curing type, or a visible light curing type is suitably used. Further, the ultraviolet curable type and visible light curing type adhesive composition can be classified into a radical polymerization hardening type adhesive composition and a cationic polymerization type adhesive composition. In the present invention, an active energy ray having a wavelength range of 10 nm to less than 380 nm is referred to as ultraviolet light, and an active energy ray having a wavelength range of 380 nm to 800 nm is referred to as visible light.

<1: Radical polymerization hardening type adhesive composition>

The curable component is, for example, a radical polymerizable compound used in a radical polymerization-curable adhesive composition. The radically polymerizable compound may be a compound having a radical polymerizable functional group having a carbon-carbon double bond, such as a (meth)acrylonyl group or a vinyl group. As the curable component, any of a monofunctional radical polymerizable compound or a difunctional or higher polyfunctional radical polymerizable compound can be used. In addition, these radically polymerizable compounds may be used alone or in combination of two or more. As such a radically polymerizable compound, for example, a compound having a (meth) acrylonitrile group is suitable. Further, in the present invention, the (meth)acrylonitrile group means an acryloyl group and/or a methacryloyl group, and "(meth)" is synonymous with the following.

Monofunctional Radical Polymerizable Compound

The monofunctional radically polymerizable compound may, for example, be a (meth) acrylamide derivative having a (meth) acrylamide group. The (meth)acrylamide derivative is preferable in that it has the advantages of high polymerization speed and excellent productivity, in addition to adhesion to a polarizer and various transparent protective films. Specific examples of the (meth) acrylamide derivative include N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-diethyl. N-alkyl group including (meth) acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N-hexyl (meth) acrylamide (meth) acrylamide derivatives; N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N-methylol-N-propane (methyl) a (meth) acrylamide derivative containing an N-hydroxyalkyl group such as acrylamide; an amine group containing a N-amino group such as an aminomethyl (meth) acrylamide or an aminoethyl (meth) acrylamide Alkyl (meth) acrylamide derivatives; N-methoxymethyl acrylamide, N-ethoxymethyl acrylamide, etc. containing N- (meth) acrylamide derivatives of alkoxy groups; (meth) acrylamides containing N-fluorenylalkyl groups such as mercaptomethyl (meth) acrylamide, mercaptoethyl (meth) acrylamide Derivatives; and so on. Further, the heterocyclic-containing (meth) acrylamide derivative in which a nitrogen atom of a (meth) acrylamide group is formed with a hetero ring may, for example, be N-propylene hydrazino or N-propenyl fluorenyl. Piperidine, N-methylpropenylpiperidine, N-propenylpyrrolidine, and the like.

Among the above (meth) acrylamide derivatives, from the viewpoint of adhesion to a polarizer and various transparent protective films, a (meth) acrylamide derivative containing an N-hydroxyalkyl group is preferred, particularly It is preferably N-hydroxyethyl (meth) acrylamide.

Further, examples of the monofunctional radically polymerizable compound include various (meth)acrylic acid derivatives having a (meth)acryloxy group. Specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and 2-methyl group. -2-nitropropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (Meth) acrylate, n-pentyl (meth) acrylate, t-pentyl (meth) acrylate, 3-pentyl (meth) acrylate, 2,2-dimethyl butyl ( Methyl) acrylate, n-hexyl (meth) acrylate, hexadecyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 4 a (meth)acrylic acid (carbon number 1 to 20) alkyl ester such as methyl-2-propylpentyl (meth) acrylate or n-octadecyl (meth) acrylate.

Further, examples of the (meth)acrylic acid derivative include a cycloalkyl group such as cyclohexyl (meth) acrylate or cyclopentyl (meth) acrylate (A). Acrylate; aralkyl (meth) acrylate such as benzyl (meth) acrylate; 2-isobornyl (meth) acrylate, 2-norbornyl methyl (meth) acrylate, 5-northene-2-yl-methyl (meth) acrylate, 3-methyl-2-norbornylmethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, Dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, polycyclic (meth) acrylate, 2-methoxyethyl (meth) acrylate Ester, 2-ethoxyethyl (meth) acrylate, 2-methoxymethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl card Alkenyl (meth) acrylate, phenoxyethyl (meth) acrylate, alkyl phenoxy polyethylene glycol (meth) acrylate, etc. containing alkoxy or phenoxy (methyl) Acrylate; etc.

Further, examples of the (meth)acrylic acid derivative include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meth) acrylate. , 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10- a hydroxyalkyl (meth) acrylate such as hydroxydecyl (meth) acrylate or 12-hydroxydodecyl (meth) acrylate, or [4-(hydroxymethyl)cyclohexyl] methacrylate, a hydroxyl group-containing (meth) acrylate such as cyclohexane dimethanol mono(meth)acrylate or 2-hydroxy-3-phenoxypropyl (meth) acrylate; a glycidyl group (methyl group) An epoxy group-containing (meth) acrylate such as acrylate or 4-hydroxybutyl (meth) acrylate glycopropyl ether; 2,2,2-trifluoroethyl (meth) acrylate, 2,2,2-Trifluoroethylethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl (meth) acrylate, octafluoropentyl (meth) acrylate Ester, heptadecafluorodecyl (meth) acrylate, 3-chloro-2- a halogen-containing (meth) acrylate such as hydroxypropyl (meth) acrylate; an alkylaminoalkyl (meth) acrylate such as dimethylaminoethyl (meth) acrylate; 3-oxygen Heterocyclic butylmethyl (meth) acrylate, 3-methyl-oxetanylmethyl (meth) acrylate, 3-ethyl-oxetanylmethyl (meth) acrylate, 3-butyl- Oxyheterobutylmethyl (meth) acrylate, 3-hexyl-oxetanylmethyl (meth) acrylate, etc. containing oxetanyl (meth) acrylate; tetrahydrofuran methyl (meth) acrylate Ester, butyrolactone (meth) acrylate, etc. (meth) acrylate having a heterocyclic ring, or hydroxytrimethyl acetic acid neopentyl glycol (meth) acrylate adduct, p-phenyl phenol (Meth) acrylate, etc.

Further, examples of the monofunctional radically polymerizable compound include (meth)acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. , isocrotonic acid, β-carboxyethyl acrylate, carboxypentyl acrylate, β-carboxyethyl methacrylate, 2-propenyloxyethyl-succinic acid, 2-propenyloxyethyl six Hydrogenic acid, 2-propenyloxyethyl phthalic acid, ω-carboxy-polycaprolactone monoacrylate, 2-propenyloxyethyltetrahydrofurfuric acid, 2-propenyloxypropoxy fluorene Acid, 2-propenyloxypropyltetrahydrofurfuric acid, 2-propenyloxypropyl hexahydrophthalic acid, methacryloxyethyl succinic acid, methacryloxyethyl phthalic acid, Methyl propylene oxiranyl ethyl tetrahydro phthalic acid, methacryl oxiranyl ethyl hexahydro phthalic acid, 2-methyl propylene methoxy methoxy methoxy acid, 2-methyl propylene methoxy propyl A monomer having a carboxyl group such as tetrahydrofurfuric acid or 2-methylpropenyloxypropyl hexahydrophthalic acid.

Further, as the monofunctional radically polymerizable compound, for example, Such as N-vinyl hydropyrrolidone, N-ethylene-ε-caprolactam, methyl ethene pyrrolidone and other internal amide amine vinyl monomers; vinyl pyridine, ethylene piperidone, vinyl pyridinium, ethylene piperazine, ethylene A vinyl-based monomer having a nitrogen-containing hetero ring or the like, such as pyrazine, vinylpyrrole, vinylimidazole, vinyloxazole or ethylene orolin.

Further, as the monofunctional radically polymerizable compound, a radically polymerizable compound having an active vinyl group can be used. The radically polymerizable compound having a reactive vinyl group is a compound having an active double bond group such as a (meth)acryl group at the terminal or molecule and having an active vinyl group. The active vinyl group may, for example, be an ethyl acetonitrile group, an alkoxypropyl fluorenyl group or a cyanoacetin group. The aforementioned reactive vinyl group is preferably an ethyl acetonitrile group. Specific examples of the radically polymerizable compound having a reactive vinyl group include 2-ethyl acetoxyethyl (meth) acrylate and 2-ethyl ethoxy propyl methacrylate (meth) acrylate. Ethyl ethoxylated alkyl (meth) acrylate such as ester, 2-ethendyloxy-1-methylethyl (meth) acrylate; 2-ethoxypropane dioxyl (meth) acrylate, 2-cyanoacetoxyethyl (meth) acrylate, N-(2-cyanoacetoxyethyl) acrylamide, N-(2-propenyl) Anthranyl butyl) acrylamide, N-(4-acetamethyleneoxymethylbenzyl) acrylamide, N-(2-acetamidoethyl) acrylamide, and the like. The radically polymerizable compound having a reactive vinyl group is preferably acetoxyethoxyalkyl (meth) acrylate.

"Polyfunctional Radical Polymerizable Compound"

Further, examples of the polyfunctional radical polymerizable compound having a difunctional or higher functional group include N,N'-methylenebis(meth)acrylamide and tripropylene glycol which are polyfunctional (meth)acrylamide derivatives. Di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9- Decanediol di(meth)acrylate, 1,10-decanediol diacrylate, 2-ethyl-2-butylpropanediol di(meth)acrylate, bisphenol A di(meth)acrylate , bisphenol A ethylene oxide adduct di(meth) acrylate, bisphenol A propylene oxide adduct di(meth) acrylate, bisphenol A diglycidyl ether di(methyl) Acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, cyclotrimethylolpropane methylal (meth) acrylate, dioxane diol Di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol Esterified product of (meth)acrylic acid and polyvalent alcohol such as penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, EO modified diglycerol tetra(meth)acrylate, 9,9 - bis[4-(2-(methyl)acryloxyethoxyethoxy)phenyl]indole. Specific examples are ARONIX M-220 (manufactured by Toagosei Co., Ltd.), Lightacrylate 1,9ND-A (manufactured by Kyoeisha Chemical Co., Ltd.), Lightacrylate DGE-4A (manufactured by Kyoeisha Chemical Co., Ltd.), and Lightacrylate DCP-A ( It is preferably manufactured by Kyoeisha Chemical Co., Ltd., SR-531 (manufactured by Sartomer Co., Ltd.), CD-536 (manufactured by Sartomer Co., Ltd.), and the like. Further, various epoxy (meth) acrylates, urethane (meth) acrylates, polyester (meth) acrylates, and various (meth) acrylate monomers may be mentioned as needed. Wait. Further, since the polyfunctional (meth) acrylamide derivative has a high polymerization rate and is excellent in productivity, and the resin composition is excellent in crosslinkability as a cured product, it is preferably contained in a curable resin composition.

When the radically polymerizable compound contains the polyfunctional radically polymerizable compound, it is possible to control the water absorption of the cured product and to satisfy the optical durability of the polarizing film in a severe humidifying environment. before Among the polyfunctional radically polymerizable compounds, a higher logPow value to be described later is preferred.

The hardenable adhesive composition for a polarizing film of the present invention preferably has a higher octanol/water partition coefficient (hereinafter referred to as a logPow value). The logPow value is an indicator of the lipophilicity of a substance and means the logarithm of the partition coefficient of octanol/water. A high logPow is representative of lipophilicity, which means low water absorption. Although the logPow value can be measured (the flask soaking method described in JIS-Z-7260), it can be calculated and calculated. This specification is a logPow value calculated using ChemDraw Ultra manufactured by Cambridgesoft. Further, the logPow value of the adhesive composition can be calculated by the following formula.

The log composition of the subsequent composition is logPow=Σ(logPowi×Wi)

logPowi: logPow value of each component of the composition

Wi: (the number of moles of the i component) / (the total number of moles of the composition of the adhesive)

The hardening type of the adhesive composition of the present invention preferably has a log Pow value of 1 or more, preferably 2 or more, and most preferably 3 or more.

Examples of the radically polymerizable compound having a high logPow include aliphatic rings such as tricyclodecane dimethanol di(meth)acrylate (logPow=3.05) and isobornyl (meth)acrylate (logPow=3.27). Methyl acrylate; 1,9-nonanediol di(meth) acrylate (logPow = 3.68), 1,10-nonanediol diacrylate (logPow = 4.10) and other long-chain aliphatic (methyl) Acrylate; hydroxytrimethylacetic acid neopentyl glycol (meth)acrylic acid adduct (logPow=3.35), 2-ethyl-2-butylpropanediol di(meth)acrylate (logPow=3.92) Multi-branched (meth) acrylate; bisphenol A di(meth) acrylate (logPow = 5.46), bisphenol A ethylene oxide 4 molar addition di(meth) propylene Acid ester (logPow=5.15), bisphenol A propylene oxide 2 molar addition di(meth)acrylate (logPow=6.10), bisphenol A propylene oxide 4 molar addition product di(methyl) Acrylate (logPow=6.43), 9,9-bis[4-(2-(methyl)acryloxyethoxyethoxy)phenyl]anthracene (logPow=7.48), p-phenylphenol (methyl) (meth) acrylate containing an aromatic ring such as acrylate (logPow=3.98);

The radical polymerizable compound is a combination of a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound from the viewpoint of the adhesion between a polarizing member and various transparent protective films and the optical durability in a severe environment. It is better. In general, it is preferably used in an amount of from 3 to 80% by weight of the monofunctional radically polymerizable compound and from 20 to 97% by weight of the polyfunctional radically polymerizable compound, based on 100% by weight of the radically polymerizable compound.

<The aspect of the radical polymerization hardening type binder composition>

When the curable component is used as the active energy ray-curable component as the curable adhesive composition for a polarizing film of the present invention, an active energy ray-curable adhesive composition can be used. When the active energy ray-curable adhesive composition is an active energy ray using an electron beam or the like, the active energy ray-curable adhesive composition does not need to contain a photopolymerization initiator, but ultraviolet rays or visible light are used as active energy. In the case of radiation, it is preferred to contain a photopolymerization initiator.

Photopolymerization initiator

The photopolymerization initiator used in the case of using a radical polymerizable compound can be suitably selected depending on the active energy ray. When hardened by ultraviolet light or visible light, a photopolymerization initiator which uses ultraviolet light or visible light cleavage is used. As The photopolymerization initiator may, for example, be diphenyl benzenedione, diphenyl ketone, benzamidine benzoic acid, or diphenyl such as 3,3'-dimethyl-4-methoxydiphenyl ketone. Ketone compound; 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)one, α-hydroxy-α,α'-dimethylethenzene, 2-methyl- An aromatic ketone compound such as 2-hydroxypropionylbenzene or α-hydroxycyclohexyl phenyl ketone; methoxyethyl benzene, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-di An acetophenone compound such as ethoxyethyl benzene or 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1; benzoin methyl ether and benzoin ethyl a benzoin ether compound such as ether, benzoin isopropyl ether, benzoin butyl ether, fennel aceton methyl ether; an aromatic ketal compound such as benzyl dimethyl ketal; or an aromatic compound such as 2-naphthalene sulfonium chloride Sulfonium chloride-based compound; photoactive lanthanide compound such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)anthracene; thioxanthone, 2-chlorothioxanthone , 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2, 4-diisopropylthioxene , Dodecyl thioxanthone thioxanthone (thioxanthone) compounds; camphor quinone; halogenated ketones; acyl phosphine oxide; acyl phosphonate and the like. Among the photopolymerization initiators, those having a higher logPow value are preferred. The photopolymerization initiator preferably has a log Pow value of 2 or more, preferably 3 or more, and most preferably 4 or more.

The amount of the photopolymerization initiator added 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 amount of the photopolymerization initiator to be added is preferably 0.01 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, still more preferably 0.1 to 5 parts by weight.

Further, when the cured adhesive composition for a polarizing film of the present invention is used, a visible light curing type containing a radical polymerizable compound is used. As the curable component, a photopolymerization initiator which is highly sensitive to light of 380 nm or more is particularly preferable. A photopolymerization initiator having a high sensitivity to light of 380 nm or more will be described in detail later.

As the photopolymerization initiator, it is preferred to use a compound represented by the following formula (1) alone or a compound of the formula (1) in combination with a photopolymerization initiator having a high sensitivity to light of 380 nm or more to be described later:

(wherein R ¹ and R ² represent -H, -CH ₂ CH ₃ , -iPr or Cl; and R ¹ and R ² may be the same or different). When the compound represented by the formula (1) is used, the photopolymerization initiator having high sensitivity to light of 380 nm or more is excellent in adhesion. Among the compounds represented by the formula (1), diethyl thioxanthone wherein R ¹ and R ² represent -CH ₂ CH ₃ is particularly preferred. In the subsequent composition, the composition ratio of the compound represented by the formula (1) is preferably 0.1 to 5 parts by weight, preferably 0.5 to 4 parts by weight, based on 100 parts by weight of the total amount of the curable component. ~3 parts by weight is more preferred.

Further, it is preferred to add a polymerization starting aid as needed. As the polymerization initiation aid, for example, triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate , 4-dimethylamino benzoic acid ethyl ester, 4-dimethylamino benzoic acid isoamyl ester, etc., especially 4-ethylamino benzoic acid ethyl ester is preferred. When a polymerization initiator is used, the amount added is relative to the curable component. The total amount is 100 parts by weight, usually 0 to 5 parts by weight, preferably 0 to 4 parts by weight, and most preferably 0 to 3 parts by weight.

Further, the initiator may be polymerized by a known light in combination with the necessity. Since light of 380 nm or less does not penetrate the transparent protective film having a UV absorbing ability, it is preferable to use a photopolymerization initiator which is highly sensitive to light of 380 nm or more as a photopolymerization initiator. Specific examples thereof include 2-methyl-1-(4-methylthiophenyl)-2-morpholinylpropan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholine) Phenyl]-1-butanone, 2,4,6-trimethylbenzylidene-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzylidene)- Phenylphosphine oxide, bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, etc. .

In particular, as the photopolymerization initiator, in addition to the compound represented by the above formula (1), a compound represented by the following formula (2) is preferably added:

(wherein R ³ , R ⁴ and R ⁵ represent -H, -CH ₃ , -CH ₂ CH ₃ , -iPr or Cl, and R ³ , R ⁴ and R ⁵ may be the same or different). As the compound represented by the formula (2), commercially available 2-methyl-1-(4-methylthiophenyl)-2-morpholinylpropan-1-one (trade name: IRGACURE 907) can be suitably used. Manufacturer: BASF). Further, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1 (trade name: IRGACURE 369, manufacturer: BASF), 2-(dimethylamine) Benzyl-2-(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (trade name: IRGACURE379, manufacturer: BASF) High sensitivity is preferred.

<The radically polymerizable compound (a1) having an active methylene group, and a radical polymerization initiator (a2) having a hydrogen abstracting action>

In the active energy ray-curable adhesive composition, when a radically polymerizable compound (a1) having an active methylene group is used as the radical polymerizable compound, it is preferred to start with a radical polymerization having hydrogen abstraction. The agent (a2) is used in combination. With this composition, particularly in a high-humidity environment or just after being taken out of water (non-dry state), the adhesion of the adhesive layer having a polarizing film is remarkably improved. This reason is not clear, but it can be presumed to be the following reason. That is, the radically polymerizable compound (a1) having an active methylene group is polymerized with another radical polymerizable compound constituting the adhesive layer, and is subjected to a main chain and/or a branch of the base polymer in the adhesive layer. Into, forming an adhesive layer. In the polymerization process, if a radical polymerization initiator (a2) having a hydrogen abstracting action is present and the base polymer constituting the adhesive layer is gradually formed, the radically polymerizable compound (a2) having an active methylene group will be Hydrogen is taken away and free radicals are generated in the methylene group. Thus, the methylene group generating the radical reacts with the hydroxyl group of the polarizer such as PVA to form a covalent bond between the adhesive layer and the polarizer. The result can be inferred, in particular, even in a non-dry state, the adhesion of the adhesive layer of the polarizing film is remarkably improved.

In the present invention, the radical polymerization initiator (a2) having a hydrogen abstracting action may, for example, be a thioxanthone-based radical polymerization initiator or a diphenylketone-based radical polymerization initiator. The radical polymerization initiator (a2) is preferably a thioxanthone-based radical polymerization initiator. The thioxanthone-based radical polymerization initiator may, for example, be a compound 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), in particular, diethyl thioxanthone of -CH ₂ CH ₃ represented by R ¹ and R ² is preferred.

When the radical energy polymerizable compound (a1) having an active methylene group and a radical polymerization initiator (a2) having a hydrogen abstracting action are contained in the active energy ray-curable adhesive composition, the curable component is When the total amount is 100% by weight, the radical polymerizable compound (a1) having the active methylene group is preferably contained in an amount of from 1 to 50% by weight, and the radical polymerization is contained in an amount of 100 parts by weight based on the total amount of the curable component. The initiator (a2) is 0.1 to 10 parts by weight.

As described above, in the present invention, when a radical polymerization initiator (a2) having a hydrogen abstracting action is present, a methylene group of a radically polymerizable compound (a1) having an active methylene group generates a radical, which is a radical. The hydroxyl group of the polarizing member such as a methyl group and a PVA reacts to form a covalent bond. Therefore, in order to generate a radical in the methylene group of the radically polymerizable compound (a1) having an active methylene group and to sufficiently form the covalent bond, it is preferred to set the total amount of the curable component to 100. When the weight % is contained, the radically polymerizable compound (a1) having an active methylene group is contained in an amount of from 1 to 50% by weight, more preferably from 3 to 30% by weight. In order to sufficiently improve the water resistance and improve the adhesion in a non-dry state, it is preferred to set the radically polymerizable compound (a1) having an active methylene group to 1% by weight or more. On the other hand, if it exceeds 50% by weight, the adhesive layer may be hardened. Further, the radical polymerization initiator (a2) having a hydrogen abstracting action is preferably contained in an amount of 0.1 to 10 parts by weight, more preferably 0.3 to 9 parts by weight, per 100 parts by weight of the total amount of the curable component. If the hydrogen abstraction reaction is to be sufficiently carried out, it is preferred to use 0.1 part by weight or more of the radical polymerization initiator (a2). On the other hand, when it exceeds 10 parts by weight, it may not be completely dissolved in the composition.

<2: Cationic polymerization hardening type adhesive composition>

The cationically polymerizable compound used for the cationically polymerizable resin composition can be classified into a monofunctional cationically polymerizable compound having one cationically polymerizable functional group in the component, and having two or more cationically polymerizable functional groups in the molecule. A polyfunctional cationically polymerizable compound. The monofunctional cationically polymerizable compound has a relatively low liquid viscosity and is contained in the resin composition to lower the liquid viscosity of the resin composition. Further, the monofunctional cationically polymerizable compound has many functional groups capable of exhibiting various functions, and is contained in the resin composition, so that the resin composition and/or the cured product of the resin composition can exhibit various functions. Since the polyfunctional cationically polymerizable compound can cause a three-dimensional cross-linking of the cured product of the resin composition, it is preferably contained in the resin composition. The ratio of the monofunctional cationically polymerizable compound to the polyfunctional cationically polymerizable compound is such that the polyfunctional cationically polymerizable compound is mixed in an amount of from 10 parts by weight to 1000 parts by weight based on 100 parts by weight of the monofunctional cationically polymerizable compound. It is better. Examples of the cationically polymerizable functional group include an epoxy group, an oxetanyl group, and a vinyl ether group. Examples of the epoxy group-containing compound include an aliphatic epoxy compound, an alicyclic epoxy compound, and an aromatic epoxy compound, and the cationically polymerizable resin composition of the present invention has curability. From the viewpoint of excellent adhesion, it is particularly preferable to contain an alicyclic epoxy compound. Examples of the alicyclic epoxy compound include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and 3,4-epoxycyclohexylmethyl- 3,4-epoxy ring Specific examples of the polycaprolactone modified product of the hexane carboxylate, the trimethyl polycaprolactone modified product or the valerolactone modified product, and the like, specifically, Celloxide 2021, Celloxide 2021A, Celloxide 2021P, Celloxide 2081, Celloxide 2083, Celloxide 2085 (above) , Daicel Chemical Industry Co., Ltd., CYRACURE UVR-6105, CYRACURE UVR-6107, CYRACURE 30, R-6110 (above, manufactured by Dow Chemical Japan Co., Ltd.), etc. Compounds with oxetanyl can be improved. The cationically polymerizable resin composition of the present invention has an effect of lowering the liquid viscosity of the composition, and therefore it is preferable to contain the compound. Examples of the compound having an oxetanyl group include 3- Ethyl-3-hydroxymethyloxetane, 1,4-bis[(3-ethyl-3-oxetanyl)methoxymethyl]benzene, 3-ethyl-3-( Phenoxymethyl)oxetane, bis[(3-ethyl-3-oxetanyl)methyl]ether, 3-ethyl-3-(2-ethylhexyloxymethyl) Oxetane, novolac oxetane, etc., commercially available as ARON OXETANE OXT-101, ARON OXETANE OXT-121, ARON OXETANE OXT-211, ARON OXETANE OXT-221, ARON OX ETANE OXT-212 (manufactured by Toagosei Co., Ltd.), etc. The compound having a vinyl ether group can improve the curability of the cationically polymerizable resin composition of the present invention, and has an effect of lowering the liquid viscosity of the composition. The substance is preferably contained. Examples of the compound having a vinyl ether group include 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. Triethylene glycol divinyl ether, cyclohexane dimethanol divinyl ether, cyclohexane dimethanol monovinyl ether, tricyclodecane vinyl ether, cyclohexyl vinyl ether, methoxy ethyl vinyl ether, ethoxylate B Vinyl ether, neopentyl alcohol type tetravinyl ether, and the like.

<Photocationic polymerization initiator>

The cationically polymerizable resin composition contains at least one compound selected from the group consisting of a compound having an epoxy group, a compound having an oxetanyl group, and a compound having a vinyl ether group as a curable component, and the like. All of them are substances which are hardened by cationic polymerization, so a photocationic polymerization initiator can be added. The photocationic polymerization initiator is irradiated with an active energy ray such as visible light, ultraviolet rays, X-rays, or electron beams to generate a cationic substance or a Lewis acid, and the polymerization reaction of the epoxy group and the oxetanyl group starts. As the photocationic polymerization initiator, a photoacid generator described later is suitably used. Further, when the curable resin composition used in the present invention is cured by visible light, it is particularly preferred to use a photocationic polymerization initiator which has high sensitivity to light of 380 nm or more, whereas a photocationic polymerization initiator is generally used. In the case of a compound that exhibits a very large absorption in the vicinity of 300 nm or a shorter wavelength range, light that is greatly absorbed by light added in a longer wavelength region, specifically, at a wavelength longer than 380 nm. The sensitizer, thus capable of sensing light at a wavelength in the vicinity, promotes the production of cationic species or acids from the photocationic polymerization initiator. Examples of the photosensitizer include a ruthenium compound, a ruthenium compound, a carbonyl compound, an organic sulfur compound, a persulfide compound, a redox compound, an azo and a diazo compound, a halide, a photoreductive dye, and the like. Two or more types can also be used in combination. In particular, the ruthenium compound is excellent in light sensitization effect, and specifically, Anthracure UVS-1331 and Anthracure UVS-1221 (manufactured by Kawasaki Kasei Co., Ltd.) are preferable. The content of the photosensitizer is preferably from 0.1% by weight to 5% by weight, more preferably from 0.5% by weight to 3% by weight.

<Other ingredients>

The hardening type adhesive composition of the present invention preferably contains the following components.

<Acrylic oligomer (A)>

In addition to the curable component of the radically polymerizable compound, the active energy ray-curable adhesive composition of the present invention may further contain an acrylic oligomer (A) obtained by polymerizing a (meth)acrylic monomer. When the active energy ray-curable adhesive composition contains the component (A), the curing energy is reduced when the active energy ray is irradiated to the composition, and the curing shrinkage is lowered, and the adhesive, the polarizing member, the transparent protective film, and the like can be lowered. The interface stress of the adherend. As a result, a decrease in the adhesion between the adhesive layer and the adherend can be suppressed. In order to sufficiently suppress the hardening shrinkage of the cured layer (adhesive layer), the content of the acrylic oligomer (A) is preferably 20 parts by weight or less, preferably about 100 parts by weight based on the total amount of the curable component. 15 parts by weight or less. When the content of the acrylic oligomer (A) in the subsequent composition is too large, the reaction rate when the composition is irradiated with active energy rays is rapidly lowered, and there is a case where the curing is poor. On the other hand, the content of the acrylic oligomer (A) is preferably 3 parts by weight or more, and preferably 5 parts by weight or more, based on 100 parts by weight of the total amount of the curable component.

In consideration of workability and uniformity at the time of coating, the active energy ray-curable adhesive composition is preferably an acrylic oligomer (A) obtained by polymerizing a (meth)acrylic monomer. ) It is also better to have a low viscosity. The acrylic oligomer having a low viscosity and preventing hardening shrinkage of the adhesive layer preferably has a weight average molecular weight (Mw) of 15,000 or less, more preferably 10,000 or less, and most preferably 5,000 or less. On the other hand, want to fully suppress The hardening shrinkage of the cured layer (adhesive layer), the weight average molecular weight (Mw) of the acrylic oligomer (A) 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 (A) include methyl (meth) acrylate, ethyl (meth) acrylate, and n-propyl (methyl). Acrylate, isopropyl (meth) acrylate, 2-methyl-2-nitropropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (methyl) Acrylate, S-butyl (meth) acrylate, t-butyl (meth) acrylate, n-pentyl (meth) acrylate, t-pentyl (meth) acrylate, 3-pentyl (meth) acrylate, 2,2-dimethylbutyl (meth) acrylate, n-hexyl (meth) acrylate, hexadecyl (meth) acrylate, n-octyl (a Acrylate, 2-ethylhexyl (meth) acrylate, 4-methyl-2-propylpentyl (meth) acrylate, N-octadecyl (meth) acrylate, etc. (methyl Acrylic acid (carbon number 1-20) alkyl esters, and, for example, cycloalkyl (meth) acrylate (for example, cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, etc.) , aralkyl (meth) acrylate (such as benzyl (meth) acrylate, etc.), polycyclic (meth) acrylate (such as 2- Isobornyl (meth) acrylate, 2-norbornylmethyl (meth) acrylate, 5-northene-2-yl-methyl (meth) acrylate, 3-methyl-2- a methyl group-containing (meth) acrylate or the like, a hydroxyl group-containing (meth) acrylate (for example, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2, 3-dihydroxypropylmethyl-butyl (methyl) methacrylate, etc.), alkoxy or phenoxy-containing (meth) acrylates (2-methoxyethyl (methyl)) Acrylate, 2-ethoxyethyl (meth) acrylate, 2-methoxymethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl Carbitol (meth) acrylate, phenoxy Ethyl (meth) acrylate, etc.), epoxy group-containing (meth) acrylates (for example, epoxy propyl (meth) acrylate), and halogen-containing (meth) acrylates (for example) 2,2,2-trifluoroethyl (meth) acrylate, 2,2,2-trifluoroethylethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl Base (meth) acrylate, octafluoropentyl (meth) acrylate, heptafluorodecyl (meth) acrylate, etc.), alkylamino alkyl (meth) acrylate (eg dimethylamine) Ethyl ethyl (meth) acrylate, etc.). These (meth) acrylates may be used alone or in combination of two or more. Specific examples of the acrylic oligomer (A) include "ARUFON" manufactured by Toagosei Co., Ltd., "ACTFLOW" manufactured by Amika Chemical Co., Ltd., and "JONCRYL" manufactured by BASF JAPAN Co., Ltd., and the like. Among the acrylic oligomers (A) obtained by polymerizing a (meth)acrylic monomer, a logPow value is preferred. The log Pow value of the acrylic oligomer (A) obtained by polymerizing the (meth)acrylic monomer is preferably 2 or more, preferably 3 or more, and most preferably 4 or more.

<Photoacid generator (B)>

The photoactive acid generator (B) may be contained in the active energy ray-curable adhesive composition. When the photo-acid generator is contained in the active energy ray-curable adhesive composition, the water resistance and durability of the adhesive layer are drastically improved as compared with the case where the photo-acid generator is not contained. The photoacid generator (B) can be represented by the following formula (3).

General formula (3) [Chemical 3] L ⁺ X ^-

(L ⁺ represents an optional phosphonium cation. Further, X ^- represents a group selected from PF6 ₆ ^- , SbF ₆ ^- , AsF ₆ ^- , SbCl ₆ ^- , BiCl ₅ ^- , SnCl ₆ ^- , ClO ₄ ^- , a counter anion composed of a thiouric acid anion and SCN-.)

Among the anions exemplified above, particularly suitable as a general formula (3), the counter anion X ^- who include PF ₆ ^-, SbF ₆ ^- and AsF ₆ ^-, and especially PF ₆ ^-, SbF ₆ ^- are preferred.

Therefore, as a specific example of a preferred onium salt constituting the photoacid generator (B) of the present invention, "CYRACURE UVI-6992", "CYRACURE UVI-6974" (above, Dow Chemical Japan Co., Ltd.), "Adekaoptomer SP150" "Adekaoptomer SP152", "Adekaoptomer SP170", "Adekaoptomer SP172" (above, ADEKA Corporation), "IRGACURE250" (made by Chiba Speciality Chemicals), "CI-5102", "CI-2855" (above, Japan's Soda Corporation, "San-Aid SI-60L", "San-Aid SI-80L", "San-Aid SI-100L", "San-Aid SI-110L", "San-Aid SI-180L" (above, Sanshin Chemical Co., Ltd.), "CPI-100P", "CPI-100A" (above, San-Apro), "WPI-069", "WPI-113", "WPI-116", WPI-041", "WPI-044", "WPI-054", "WPI-055", "WPAG-281", "WPAG-567", "WPAG-596" (above, Wako Pure Chemical Industries, Ltd.) A preferred specific example of the photoacid generator (B) of the present invention is mentioned.

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

<Compound (C) containing either an alkoxy group or an epoxy group>

Among the above active energy ray-curable adhesive compositions, active The photo-ray-curable adhesive composition may be used in combination with a photoacid generator (B) and a compound (C) containing either an alkoxy group or an epoxy group.

(epoxy group-containing compound and polymer) (C)

When a compound having one or more epoxy groups in the molecule or a polymer (epoxy resin) having two or more epoxy groups in the molecule is used, it is also possible to use two or more functional groups reactive with an epoxy group in the molecule. Base compound. Here, the functional group reactive with an epoxy group may, for example, be a carboxyl group, a phenolic hydroxyl group, a fluorenyl group, a primary or secondary aromatic group or the like. In view of the unidimensional hardenability, it is particularly preferable that these functional groups have two or more in one molecule.

Examples of the polymer having one or more epoxy groups in the molecule include epoxy resins such as bisphenol A type epoxy resins derived from bisphenol A and epichlorohydrin, bisphenol F and epoxy. Bisphenol F type epoxy resin derived from chloropropane, bisphenol S type epoxy resin, novolac type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolac type epoxy group Resin, bisphenol F novolak type epoxy resin, alicyclic epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, naphthalene type epoxy resin, biphenyl type ring Polyfunctional epoxy resin such as oxy resin, fluorene type epoxy resin, trifunctional epoxy resin or tetrafunctional epoxy resin, epoxy propyl ester type epoxy resin, epoxy propyl group An amine type epoxy resin, an intramethylene urea type epoxy resin, a trimeric isocyanate type epoxy resin, an aliphatic chain epoxy resin, etc., and the epoxy resins may also be halogenated. hydrogenation. As a commercially available epoxy resin product, JER Court 828, 1001, 801N, 806, 807, 152, 604, 630, 871, YX8000, YX8034, YX4000, and DIC Corporation, manufactured by Japan Epoxy Resins Co., Ltd., may be mentioned. It EPICLON 830, EXA835LV, HP4032D, HP820, EP4100 series, EP4000 series, EPU series manufactured by ADEKA Co., Ltd., Celloxide series (2021, 2021P, 2083, 2085, 3000, etc.) manufactured by Daicel Chemical Co., Ltd., EPOLEAD series, EHPE series, YD series, YDF series, YDCN series, YDB series, phenoxy resin (polyhydroxy polyether synthesized by bisphenols and epichlorohydrin and having epoxy groups at both ends; YP series) manufactured by Nippon Steel Chemical Co., Ltd. Etc., the Denacol series manufactured by Nagase ChemteX, the Epolite series manufactured by Kyoritsu Chemical Co., Ltd., etc., but are not limited thereto. These epoxy resins may be used in combination of two or more kinds. Further, when the glass transition temperature Tg of the adhesive layer is calculated, the epoxy group-containing compound and the polymer (C) are not counted.

(C alkoxy group-containing compound and polymer) (C) The compound having an alkoxy group in the molecule is not particularly limited as long as it has one or more alkoxy groups in the molecule, and a known one can be used. As such a compound, a melamine compound, an amine resin, a decane coupling agent, etc. are mentioned as a representative. Further, when the glass transition temperature Tg of the adhesive layer is calculated, the alkoxy group-containing compound and the polymer (C) are not counted.

The amount of the compound (C) containing any one of an alkoxy group and an epoxy group is usually 30 parts by weight or less based on 100 parts by weight of the total amount of the curable component, and the content of the compound (C) in the composition is Too much, the adhesion will be lowered, and the impact resistance of the drop test will be deteriorated. The content of the compound (C) in the composition is preferably 20 parts by weight or less. On the other hand, the compound (C) is preferably contained in an amount of 2 parts by weight or more, and more preferably 5 parts by weight or more, from the viewpoint of water resistance.

<decane coupling agent (D)>

When the curable adhesive composition for a polarizing film of the present invention is an active energy ray curable curing type, the decane coupling agent (D) is preferably a compound using active energy ray curability, but it is not active energy ray hardening property. It can also give the same water resistance.

Specific examples of the decane coupling agent (D) include, as an active energy ray-curable compound, ethylene trichlorodecane, ethylene trimethoxy decane, ethylene triethoxy decane, and 2-(3, 4-epoxy ring). Hexyl)ethyltrimethoxydecane, 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropylmethyldiethoxydecane, 3-glycidoxypropyltri Ethoxy decane, p-styryl trimethoxy decane, 3-methyl propylene methoxy propyl methyl dimethoxy decane, 3-methyl propylene methoxy propyl trimethoxy decane, 3- Methyl propylene methoxy propyl methyl diethoxy decane, 3-methyl propylene methoxy propyl triethoxy decane, 3- propylene methoxy propyl trimethoxy decane, and the like.

Preferred is 3-methacryloxypropyltrimethoxydecane, 3-propenyloxypropyltrimethoxydecane.

As a specific example of the decane coupling agent which is not an active energy ray hardening property, a decane coupling agent (D1) having an amine group is preferred. Specific examples of the decane coupling agent (D1) having an amine group include γ-aminopropyltrimethoxydecane, γ-aminopropyltriethoxydecane, and γ-aminopropyltriisopropyl. Oxydecane, γ-aminopropylmethyldimethoxydecane, γ-aminopropylmethyldiethoxydecane, γ-(2-aminoethyl)aminopropyltrimethoxydecane , γ-(2-aminoethyl)aminopropylmethyldimethoxydecane, γ-(2-aminoethyl)aminopropyltriethoxydecane, γ-(2-amino group Ethyl)aminopropylmethyldiethoxy Decane, γ-(2-aminoethyl)aminopropyltriisopropoxydecane, γ-(2-(2-aminoethyl)aminoethyl)aminopropyltrimethoxydecane, Γ-(6-Aminohexyl)aminopropyltrimethoxydecane, 3-(N-ethylamino)-2-methylpropyltrimethoxydecane, γ-ureidopropyltrimethoxydecane , γ-ureidopropyltriethoxydecane, N-phenyl-γ-aminopropyltrimethoxydecane, N-benzyl-γ-aminopropyltrimethoxydecane, N-vinylbenzyl -γ-Aminopropyltriethoxydecane, N-cyclohexylaminomethyltriethoxydecane, N-cyclohexylaminomethyldiethoxymethyldecane, N-phenylaminomethyl Alkyltrimethoxydecane, (2-aminoethyl)aminomethyltrimethoxydecane, N,N'-bis[3-(trimethoxyindolyl)propyl]ethylenediamine, etc. a ketimine-type decane such as N-(1,3-dimethylbutylidene)-3-(triethoxyindolyl)-1-propanamine.

The decane coupling agent (D1) having an amine group may be used singly or in combination of plural kinds. Among these, γ-aminopropyltrimethoxydecane, γ-(2-aminoethyl)aminopropyltrimethoxydecane, γ-(2) are preferred in order to ensure good adhesion. -aminoethyl)aminopropylmethyldimethoxydecane, γ-(2-aminoethyl)aminopropyltriethoxydecane, γ-(2-aminoethyl)amine Propylmethyldiethoxydecane, N-(1,3-dimethylbutylidene)-3-(triethoxyindolyl)-1-propanamine.

The amount of the decane coupling agent (D) to be added is preferably in the range of 0.01 to 20 parts by weight, preferably 0.05 to 15 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the total amount of the curable component. good. When the amount is more than 20 parts by weight, the storage stability of the adhesive composition is deteriorated, and when it is less than 0.1 part by weight, the effect of the subsequent water resistance cannot be sufficiently exhibited. In addition, when calculating the glass transition temperature Tg of the adhesive layer, the decane coupling agent is not calculated. (D).

Specific examples of the decane coupling agent other than the above-mentioned active energy ray-curable exemplifying agent include 3-ureidopropyltriethoxydecane, 3-chloropropyltrimethoxydecane, and 3-mercaptopropylmethyl Dimethoxy decane, 3-mercaptopropyltrimethoxy decane, bis(triethoxymethyl propyl) tetrasulfide, 3-isocyanate propyl triethoxy decane, imidazolium, and the like.

<Compound (E) with vinyl ether group>

When the hardenable adhesive composition for a polarizing film of the present invention contains the compound (E) having a vinyl ether group, the water resistance of the polarizer and the adhesive layer is improved, which is preferable. Although the reason for obtaining this effect is not clear, one of the reasons is that the vinyl ether group of the compound (E) interacts with the polarizer, so that the adhesion between the polarizer and the adhesive layer becomes high. In order to further improve the water resistance of the polarizer and the adhesive layer, the compound (E) is preferably a radical polymerizable compound having a vinyl ether group. Further, the content of the compound (E) is preferably 0.1 to 19 parts by weight based on 100 parts by weight of the total amount of the curable component.

<Compound (F) which produces keto-enol tautomerism>

The hardenable adhesive composition for a polarizing film of the present invention may contain a compound which produces keto-enol tautomerism. For example, an adhesive composition containing a crosslinking agent or an adhesive composition to which a crosslinking agent can be added is preferably one which contains the above-mentioned compound which produces keto-enol tautomerism. Thereby, it is possible to suppress an excessive increase in viscosity or gelation of the adhesive composition and formation of a microgel after the addition of the organometallic compound, and it is possible to achieve an effect of prolonging the life of the composition.

As the compound (F) which produces keto-enol tautomerism, various β-dicarbonyl compounds can be used. Specific examples thereof include acetamidine acetone, 2,4-hexanedione, 3,5-heptanedione, 2-methylhexyl-3,5-dione, and 6-methylheptyl-2,4. a β-diketone such as diketone or 2,6-dimethylheptyl-3,5-dione; methyl acetate acetate, ethyl acetate, isopropyl acetate, acetonitrile tert - acetoacetate such as butyl ester; ethyl acetate, ethyl acetonate, isopropyl acetate, butyl acetate, tert-butyl acetate, etc.; Isobutyl hydrazine acetate such as isobutyl hydrazine ethyl acetate, isobutyl hydrazine acetate, tert-butyl acetate such as tert-butyl acetate; malonic acid ester such as methyl malonate or ethyl malonate; . Among them, as a suitable compound, acetamidineacetone and acetamidine acetate are mentioned. The compound (F) which produces keto-enol tautomerism may be used singly or in combination of two or more.

The compound which produces keto-enol tautomerism is used in an amount of 0.05 parts by weight to 10 parts by weight, preferably 0.2 parts by weight to 3 parts by weight, based on 1 part by weight of the organometallic compound, for example, 0.3 parts by weight. 2 parts by weight). When the amount of the compound used is less than 0.05 part by weight based on 1 part by weight of the organometallic compound, it may be difficult to exhibit a sufficient use effect. On the other hand, when the amount of the compound is more than 10 parts by weight based on 1 part by weight of the organometallic compound, there is an excessive interaction with the organometallic compound, and the water resistance for the purpose may be difficult to express.

<Additives other than the above>

Further, the curable adhesive composition for a polarizing film of the present invention may contain other optional components as various additives within a range not impairing the object and effect of the present invention. As the additive, an epoxy resin, Polyamide, polyamidimide, polyurethane, polybutadiene, polychloroprene, polyether, polyester, styrene-butadiene block copolymer, petroleum resin, xylene a polymer or oligomer such as a resin, a ketone resin, a cellulose resin, a fluorine-based oligomer, a polyoxymethylene oligomer, or a polysulfide oligomer; phenothiazine, 2,6-di-t- Polymerization inhibitors such as butyl-4-cresol; polymerization initiator; leveling agent; wettability improver; surfactant; plasticizer; ultraviolet absorber; inorganic filler; pigment; dye, etc. Among the various additives, the higher the logPow value is preferred. The logPow value of each of the additives is preferably 2 or more, preferably 3 or more, and most preferably 4 or more.

The additive is usually 0 to 10 parts by weight, preferably 0 to 5 parts by weight, more preferably 0 to 3 parts by weight, based on 100 parts by weight of the total amount of the curable component.

<Adhesiveness of adhesive composition>

The curable adhesive composition for a polarizing film of the present invention contains the curable component, and the adhesiveness of the adhesive composition is preferably 100 cp or less at 25 ° C from the viewpoint of coatability. On the other hand, when the cured adhesive composition for a polarizing film of the present invention exceeds 100 cp at 25 ° C, the temperature of the adhesive composition can be controlled at the time of coating to be adjusted to 100 cp or less. The preferred range of viscosity is from 1 to 80 cp, preferably from 10 to 50 cp. The viscosity was measured using an E-type viscometer TVE22LT manufactured by Toki Sangyo Co., Ltd.

Further, from the viewpoint of safety, the curable adhesive composition for a polarizing film of the present invention is preferably a material having a low skin irritation as the curable component. Skin irritation can be judged by the P.I.I index. P.I.I is widely used as a degree of skin disorder and is measured by Cui's test. set. The measured value is in the range of 0 to 8. The smaller the value, the lower the irritancy is determined. However, the error of the measured value is large, so it is preferable as a reference value. P.I.I is preferably 4 or less, preferably 3 or less, and most preferably 2 or less.

<Total water absorption rate>

In the hardenable adhesive composition for a polarizing film of the present invention, the cured product obtained by curing the curable adhesive composition is immersed in pure water at 23 ° C for 24 hours, and the total water absorption measured as described above is 10 weight. % below is better. When the polarizing film is subjected to severe high temperature and high humidity (85 ° C / 85% RH, etc.), the water that penetrates the transparent protective film and the adhesive layer will invade the polarizing member, and the crosslinked structure will be hydrolyzed to cause two colors. The alignment of the pigments is disturbed, and the optical durability such as an increase in the transmittance and a decrease in the degree of polarization is deteriorated. When the total water absorption rate of the adhesive layer is 10% by weight or less and the polarizing film is placed in a severe high-temperature and high-humidity environment, the movement of water toward the polarizing member is suppressed, and the transmittance of the polarizing member can be suppressed from increasing. The degree of polarization is reduced. The overall water absorption is preferably 5% by weight or less, more preferably 3% by weight or less, from the viewpoint that the optical durability of the adhesive layer of the polarizing film is better in a severe environment at a high temperature. Preferably, it is 1% by weight or less. On the other hand, when the polarizer is bonded to the transparent protective film, the polarizer retains a certain amount of moisture, and when the composition of the hardened adhesive is in contact with the moisture of the polarizer, unevenness such as unevenness or bubbles may occur. In order to suppress the appearance defect, the hardening type adhesive composition preferably absorbs a certain amount of moisture. Specifically, the total water absorption is preferably 0.01% by weight or more, preferably 0.05% by weight or more. Specifically, the total water absorption rate is measured by the water absorption rate test method described in JIS K 7209.

<hardening shrinkage rate>

Further, the curable adhesive composition for a polarizing film of the present invention has a curable component, and when the curable adhesive composition is cured, curing shrinkage usually occurs. The curing shrinkage ratio is an index indicating the ratio of hardening shrinkage when the adhesive layer is formed of the cured adhesive composition for a polarizing film. When the curing shrinkage ratio of the coating layer is increased, the cured film composition for a polarizing film is cured to form an adhesive layer, and interfacial deformation occurs, which suppresses the occurrence of defects. From the above viewpoints, the cured shrinkage ratio of the cured product obtained by curing the cured adhesive composition of the polarizing film of the present invention is preferably 10% or less. The hardening shrinkage ratio is preferably small, and the hardening shrinkage ratio is preferably 8% or less, more preferably 5% or less. The hardening shrinkage ratio is measured by the method described in JP-A-2013-104869, and specifically, it is measured by a method using a curing shrinkage sensor manufactured by Sentech.

<Polarized film>

In the polarizing film of the present invention, a transparent protective film is bonded to an adhesive layer formed by passing through the cured layer of the cured adhesive composition for a polarizing film on at least one surface of the polarizing member. The adhesive layer belonging to the above-mentioned cured layer is as described above, and the overall water absorption is preferably 10% by weight or less.

<Binder layer>

The thickness of the adhesive layer formed by the above-mentioned hardening type adhesive composition is preferably controlled to be 0.1 to 3 μm. The thickness of the subsequent layer is preferably 0.3 to 2 μm, more preferably 0.5 to 1.5 μm. When the thickness of the layer of the second layer is 0.1 μm or more, the occurrence of adhesion defects due to the cohesive force of the adhesive layer is suppressed, and It is preferable to produce a poor appearance (bubble) when laminating. On the other hand, if the adhesive layer becomes thicker than 3 μm, the polarizing film may fail to satisfy the durability.

Further, the curable adhesive composition is preferably selected such that the Tg of the adhesive layer formed is 60 ° C or higher, more preferably 70 ° C or higher, more preferably 75 ° C or higher, and even 100. Above °C is preferred, and more preferably above 120 °C. On the other hand, if the Tg of the adhesive layer is too high, the flexibility of the polarizing film is lowered. Therefore, the Tg of the adhesive layer is 300 ° C or lower, more preferably 240 ° C or lower, and even more preferably 180 ° C or lower. . Tg <glass transition temperature> was measured using the dynamic viscoelasticity measuring apparatus RSAIII manufactured by TA INSTRUMENTS using the following measurement conditions.

Sample size: width 10 mm, length 30 mm, jaw distance 20 mm, measurement mode: stretching, cycle frequency: 1 Hz, temperature increase rate: 5 ° C / minute for dynamic viscoelasticity measurement, using the temperature Tg as the peak of tan δ.

Further, the curable adhesive composition preferably has a storage elastic modulus of the adhesive layer formed at a temperature of 25 ° C of 1.0 × 10 ⁷ Pa or more, and preferably 1.0 × 10 ⁸ Pa or more. Further, the storage elastic modulus of the adhesive layer was 1.0 × 10 ³ Pa to 1.0 × 10 ⁶ Pa, which was different from the storage elastic modulus of the adhesive layer. The storage elastic modulus of the subsequent layer affects the cracking of the polarizer when the polarizing film is subjected to thermal cycling (from -40 ° C to 80 ° C, etc.), and when the storage elastic modulus is low, the polarizing member crack is likely to occur. The temperature range having a high storage modulus is preferably 80 ° C or less, and preferably 90 ° C or less. The storage elastic modulus was measured in the same measurement conditions as the Tg <glass transition temperature> using the dynamic viscoelasticity measuring apparatus RSAIII manufactured by TA INSTRUMENTS. The dynamic viscoelasticity was measured using the value of the storage elastic modulus (E').

The polarizing film of the present invention can be produced by a manufacturing method comprising the following steps:

a coating step of applying a curing adhesive composition for a polarizing film on at least one side of the polarizing member and the transparent protective film; a bonding step of bonding the polarizing member and the transparent protective film; and a subsequent step of the side of the polarizing member Or the active energy ray is irradiated to the side of the transparent protective film surface, the active energy ray-curable adhesive composition is cured to obtain an adhesive layer, and the polarizer and the transparent protective film are passed through the adhesive layer. In the manufacturing method, the moisture content of the polarizing member in the bonding step is preferably 8 to 19%.

The polarizing member and the transparent protective film may be subjected to surface modification treatment before the application of the above-mentioned hardening type adhesive composition. Specific treatments include corona treatment, plasma treatment, and saponification treatment.

The coating method of the hardened adhesive composition can be suitably selected depending on the viscosity of the composition and the thickness of the object. Examples of the coating method include reverse coating, gravure coating (direct, reverse, and offset), reverse bar coating, roll coating, die coating, bar coating, and rod. Coating, etc. Other coatings may also be suitably carried out by means of a dipping method or the like.

The polarizing member and the transparent protective film are bonded to each other by the hardening type adhesive composition as described above. The bonding of the polarizing member and the transparent protective film can be carried out using a roll laminator.

<hardening of the composition of the adhesive>

The curable adhesive composition for a polarizing film of the present invention can be used as an active energy ray-curable adhesive composition. The active energy ray-curable adhesive composition can be used in the form of an electron beam curing type, an ultraviolet curing type, and a visible light curing type. The aspect of the hardening type adhesive composition is preferably a visible light hardening type adhesive composition from the viewpoint of productivity.

Active Light Ray Hardening Type

The active energy ray-curable adhesive composition is formed by irradiating an active energy ray (electron beam, ultraviolet ray, visible light, etc.) after the polarizer and the transparent protective film are bonded, and hardening the active energy ray-curable adhesive composition. Then the agent layer. The direction of irradiation of the active energy ray (electron beam, ultraviolet light, visible light, etc.) can be irradiated from an optional suitable direction. It is preferred to irradiate from the side of the transparent protective film. When irradiated from the side of the polarizer, the polarizer may be deteriorated due to active energy rays (electron beam, ultraviolet light, visible light, etc.).

"Electron beam hardening type"

Regarding the electron beam curing type, the irradiation condition of the electron beam is any suitable condition as long as it belongs to the above-described conditions for curing the active energy ray-curable adhesive composition. For example, in the case of electron beam irradiation, the acceleration voltage is preferably 5 kV to 300 kV, more preferably 10 kV to 250 kV. If the accelerating voltage is less than 5kV, the electron beam will not reach the adhesive and cause insufficient hardening. If the accelerating voltage exceeds 300kV, the penetration of the sample will be too strong, which will damage the transparent protective film or polarizer. The amount of irradiation line is 5 to 100 kGy, preferably 10 to 75 kGy. When the amount of irradiation line is less than 5kGy, the adhesive will harden insufficiently. If it exceeds 100kGy, it will damage the transparent protective film or polarizer, causing the machine. The mechanical strength is reduced or yellowed, and specific optical properties cannot be obtained.

The electron beam irradiation is usually carried out in an inert gas, and if necessary, in the atmosphere or with a small amount of oxygen. Depending on the material of the transparent protective film, proper introduction of oxygen deliberately causes oxygen barrier on the surface of the initial electron beam contacting the transparent protective film, preventing the transparent protective film from being damaged, and effectively illuminating the electron beam only for the adhesive.

"Ultraviolet hardening type, visible light hardening type"

In the method for producing a polarizing film of the present invention, as the active energy ray, it is preferred to use a ray containing a visible light having a wavelength range of 380 nm to 450 nm, particularly a visible light having a wavelength range of 380 nm to 450 nm. Active energy rays are preferred. In the ultraviolet curing type and visible light curing type, when a transparent protective film (ultraviolet-opaque transparent protective film) which imparts ultraviolet absorbing energy is used, light having a wavelength shorter than about 380 nm and light having a shorter wavelength than 380 nm are absorbed. The active energy ray-curable adhesive composition could not be reached, and its polymerization reaction did not help. Further, light having a wavelength shorter than 380 nm absorbed by the transparent protective film is converted into heat, and the transparent protective film itself generates heat, which causes a defect such as bending or wrinkles of the polarizing film. Therefore, when the ultraviolet curable type or visible light hardening type of the present invention is used, it is preferable to use an apparatus which does not emit light having a wavelength shorter than 380 nm as an active energy ray generating apparatus, and more specifically, a wavelength range of 380 to 440 nm. The ratio of the integrated illuminance to the integrated illuminance of the wavelength range of 250 to 370 nm is preferably 100:0 to 100:50, more preferably 100:0 to 100:40. As the active energy ray of the present invention, a metal halide lamp in which gallium is enclosed and an LED light source having a wavelength range of 380 to 440 nm are preferably used. Or, you can use low Pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, ultra high pressure mercury lamp, white heat bulb, xenon lamp, halogen lamp, carbon arc lamp, metal halide lamp, fluorescent lamp, tungsten lamp, gallium lamp, excimer laser or sunlight, etc. A source of ultraviolet light and visible light can also be used by a band pass filter to shield ultraviolet light having a wavelength shorter than 380 nm. In order to improve the adhesion performance of the adhesive layer between the polarizer and the transparent protective film, and to prevent the bending of the polarizing film, it is preferable to use a metal halide lamp in which gallium is enclosed, and pass through a band pass filter capable of shielding light having a wavelength shorter than 380 nm. The active energy ray obtained by the device, or the active energy ray of wavelength 405 nm obtained by the LED light source.

Regarding the ultraviolet curing type or the visible light curing type, it is preferred to heat the active energy ray-curable adhesive composition before heating (visual heating before irradiation), and it is preferable to increase the temperature to 40 ° C or higher. It is preferred to heat to 50 ° C or higher. In addition, it is preferred to warm the active energy ray-curable adhesive composition after irradiation with ultraviolet light or visible light (warming after irradiation), in which case it is preferably heated to 40 ° C or higher to be heated to 50 ° C. The above is preferred.

The active energy ray-curable adhesive composition of the present invention is particularly suitably used in forming a transparent protective film for a polarizing member and a light transmittance of less than 5% at a wavelength of 365 nm, followed by an adhesive layer. In this case, the active energy ray-curable adhesive composition of the present invention is irradiated with a transparent protective film having UV absorbing energy by a photopolymerization initiator containing the above formula (1), and can be hardened to form an adhesive layer. . Therefore, even if a polarizing film having a transparent protective film having UV absorbing energy is laminated on both areas of the polarizing member, the adhesive layer can be cured. But of course, for the product A polarizing film formed by laminating a transparent protective film having no UV absorbing energy can also harden the adhesive layer. Further, the transparent protective film having UV absorbing energy means a transparent protective film having a transmittance of less than 10% for light of 380 nm.

The method of imparting UV absorbing energy to the transparent protective film includes a method of including an ultraviolet absorber in the transparent protective film, and a method of including a surface treatment layer of the ultraviolet absorber on the surface layer of the transparent protective film.

Specific examples of the ultraviolet absorber include, for example, a well-known oxydiphenylketone compound, a benzotriazole compound, a salicylate compound, a diphenylketone compound, a cyanoacrylate compound, and a nickel offset. A salt-containing compound, a triazine-based compound, or the like.

After the polarizer is bonded to the transparent protective film, an active energy ray (electron beam, ultraviolet ray, visible light, or the like) is irradiated to cure the active energy ray-curable adhesive composition to form an adhesive layer. The direction of irradiation of the active energy ray (electron beam, ultraviolet light, visible light, etc.) can be irradiated from an optional suitable direction. It is preferred to irradiate from the side of the transparent protective film. When irradiated from the side of the polarizer, the polarizer may be deteriorated due to active energy rays (electron beam, ultraviolet light, visible light, etc.).

When the polarizing film of the present invention is produced on a continuous production line, the line speed is preferably from 1 to 500 m/min, preferably from 5 to 300 m/min, and from 10 to 100 m/min, depending on the hardening time of the adhesive composition. Better. When the production line speed is too small, there is a lack of productivity, or excessive damage to the transparent protective film, and it is impossible to produce a polarizing film that has been subjected to durability tests and the like. Line speed When the degree is too large, the curing of the adhesive composition is insufficient, and there is a case where the intended adhesion is not obtained.

Further, in the polarizing film of the present invention, the adhesive layer formed by the cured layer of the active energy ray-curable adhesive composition is bonded to the polarizing member and the transparent protective film, and the transparent protective film and the adhesive layer are Easy to connect layers can be set. The easy-adhesive layer may be, for example, various resins having a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a polyoxane-based, a polyamide-based skeleton, a polyimine skeleton, a polyvinyl alcohol skeleton, and the like. Formed. These polymer resins may be used alone or in combination of two or more. Further, other additives may be added to the formation of the easy adhesion layer. Specifically, a stabilizer such as an adhesion-imparting agent, an ultraviolet absorber, an antioxidant, or a heat-resistant stabilizer can be additionally used.

The easy-adhesive layer is usually first disposed on the transparent protective film, and the side of the easy-adhesion layer of the transparent protective film and the polarizing member are bonded together by the adhesive layer. Regarding the formation of the easy-adhesion layer, the formation of the easily-adhesive layer can be applied and dried by a known technique on a transparent protective film. The material of the easy-adhesion layer is usually adjusted to a solution diluted to an appropriate concentration in consideration of the thickness after drying, the smoothness of coating, and the like. The thickness of the easily-adherent layer after drying is preferably 0.01 to 5 μm, preferably 0.02 to 2 μm, more preferably 0.05 to 1 μm. Further, the easy-adhesion layer may be provided with a plurality of layers, and in this case, the total thickness of the easy-adhesion layer is preferably set to the above range.

<polarizer>

The polarizer is not particularly limited, and various polarizers can be used. Examples of the polarizing member include a polyvinyl alcohol-based film and a partially formalized polyvinyl alcohol. Film, ethylene. In a hydrophilic polymer film such as a partially saponified film of a vinyl acetate copolymer, a dichroic material such as iodine or a dichroic dye is adsorbed and uniaxially stretched, and a dehydrated material of polyvinyl alcohol or polyvinyl chloride is exemplified. A polyene-based alignment film such as a hydrochloric acid-treated product. Among these, a polarizing member comprising a polyvinyl alcohol-based film and a dichroic material such as iodine is suitable. The thickness of the polarizing members is not particularly limited, and is generally about 80 μm or less.

The polarizing material in which the polyvinyl alcohol-based film is iodine-dyed and uniaxially stretched can be produced, for example, by dyeing polyvinyl alcohol by immersion in an aqueous solution of iodine and extending it to 3 to 7 times the original length. It may be immersed in an aqueous solution such as boric acid or potassium iodide as needed. The polyvinyl alcohol-based film may be immersed in water for washing with water before the dyeing as needed. By washing the polyvinyl alcohol-based film with water, the stain or the anti-caking agent on the surface of the polyvinyl alcohol-based film can be washed, and the polyvinyl alcohol-based film can be swollen, thereby preventing unevenness in dyeing unevenness. The extension can be carried out after iodine dyeing, or it can be extended while dyeing, or it can be extended and then subjected to iodine dyeing. It can also be extended in an aqueous solution such as boric acid or potassium iodide or in a water bath.

In addition, when a thin polarizer having a thickness of 10 μm or less is used as the polarizer, the effect of the composition of the curable adhesive composition of the present invention (the optical durability in a severe environment under high temperature and high humidity) can be remarkably exhibited. The polarizing member having a thickness of 10 μm or less has a relatively large influence on moisture as compared with a polarizing member having a thickness of more than 10 μm, and the optical durability in an environment under high temperature and high humidity is insufficient, and the transmittance is likely to increase or the degree of polarization is lowered. . Therefore, the polarizer of 10 μm or less and the hardenable adhesive composition for a polarizing film of the present invention (containing a metal alkoxide and a metal chelate compound) An adhesive layer composed of a cured product constituting at least one organometallic compound in the group, and an adhesive layer having a total water absorption of 10% by weight or less is laminated, under severe high temperature and high humidity In the environment, the movement of the water toward the polarizer is suppressed, so that the deterioration of the optical durability such as the increase in the transmittance of the polarizing film and the decrease in the degree of polarization can be remarkably suppressed. The thickness of the polarizer is preferably 1 to 7 μm from the viewpoint of thickness reduction. Such a thin polarizer has a small thickness unevenness, is excellent in visibility, and has little dimensional change, and is also preferable because the thickness of the polarizing film is also thinner.

Typical examples of the thin-type polarizing members include the specifications of JP-A-51-069644, JP-A-2000-338329, WO2010/100917, PCT/JP2010/001460, and JP-A-2010-269002. The thin polarizing film described in the specification of Japanese Patent Application No. 2010-263692. These thin polarizing films are obtained by a method comprising a step of stretching a layer of a polyvinyl alcohol-based resin (hereinafter also referred to as a PVA-based resin) and a resin substrate for stretching in a state of being laminated, and a step of dyeing. According to this method, even if the PVA-based resin layer is thin, it can be stretched by the resin substrate for stretching, and can be extended without causing defects such as breakage due to stretching.

In the above-mentioned thin polarizing film, in the method of including the step of stretching in the state of the laminated body and the step of dyeing, from the viewpoint of being able to extend at a high magnification and improving the polarizing performance, it is a manual such as WO2010/100917, PCT. /JP2010/001460, or the purpose of the specification of the Japanese Patent Application No. 2010-263692, and the specification of the Japanese Patent Application No. 2010-263692, which is preferably obtained by the method of the step of extending the aqueous solution of boric acid, especially the special wish 2010-269002 No. 2010-263692 It is preferred to carry out a method comprising the step of performing an auxiliary aerial extension before extending in an aqueous solution of boric acid.

<Transparent protective film>

The material which is formed on the one surface or both surfaces of the polarizer is preferably excellent in transparency, mechanical strength, thermal stability, moisture shielding property, and the like. For example, a polyester-based polymer such as polyethylene terephthalate or polyethylene naphthalate, a cellulose-based polymer such as diethyl cellulose or triethyl fluorenyl cellulose, or polymethyl methacrylate An acrylic polymer such as an ester, a styrene polymer such as polystyrene or acrylonitrile ‧ styrene copolymer (AS resin), or a polycarbonate polymer. Further, such as polyethylene, polypropylene, a polyolefin having a ring- or norbornene structure, a polyolefin polymer of a vinyl/propylene copolymer, a vinyl chloride polymer, a nylon or an aromatic polyamide, and the like. Polymer, quinone imine polymer, fluorene polymer, polyether fluorene polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinyl chloride polymer Further, an ethylene butyral polymer, a polyarylate polymer, a polyoxymethylene polymer, an epoxy polymer, or a mixture of the above polymers is also an example of a polymer forming the transparent protective film. The transparent protective film may contain one or more optional additives as appropriate. The additive may, for example, be an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color preventive agent, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a colorant or the like. The content of the above thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, preferably 50 to 99% by weight, more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. . The content of the above thermoplastic resin in the transparent protective film is 50 When the amount is less than or equal to a part, the high transparency and the like which the thermoplastic resin originally has may not be sufficiently exhibited.

Further, as the transparent protective film, a polymer film described in JP-A-2001-343529 (WO01/37007), for example, a thermoplastic resin containing (A) a branched chain having a substituted and/or unsubstituted quinone group. And (B) a resin composition of a thermoplastic resin having a substituted and/or unsubstituted phenyl group and a nitrile group. Specific examples include an alternating copolymer of isobutylene and N-methylbutyleneimine and acrylonitrile. A film of a resin composition of a styrene copolymer. As the film, a film composed of a mixed product of a resin composition or the like can be used. Since these films have a small phase difference and a small photoelastic coefficient, they are capable of solving the problem of unevenness due to distortion of the polarizing film, and also have low moisture permeability and excellent humidifying durability.

In the above polarizing film, the moisture permeability of the transparent protective film is preferably 150 g/m ² /24 h or less. According to this configuration, it is difficult for the moisture in the air to enter the polarizing film, and the change in the moisture content of the polarizing film itself can be suppressed. As a result, it is possible to suppress the bending and dimensional change of the polarizing film caused by the storage environment.

The material which is formed on the one or both surfaces of the polarizing member is preferably a transparent material, a mechanical strength, a thermal stability, a moisture shielding property, an isotropic property, etc., particularly in a moisture permeability. It is preferably 150 g/m ² /24 h or less, particularly preferably 140 g/m ² /24 h or less, and more preferably 120 g/m ² /24 h or less. The moisture permeability can be determined by the method described in the examples.

a material for forming a transparent protective film having the aforementioned low moisture permeability, For example, a polyester resin such as polyethylene terephthalate or polyethylene naphthalate; a polycarbonate resin; a polyarylate resin; a guanamine resin such as nylon or an aromatic polyamide; A polyolefin polymer of a polypropylene, an ethylene/propylene copolymer, a cycloolefin resin having a ring system or a norbornene structure, a (meth)acrylic resin, or a mixture thereof. Among the above resins, a polycarbonate resin, a cyclic polyolefin resin, or a (meth)acrylic resin is preferred, and a cycloolefin resin or a (meth)acrylic resin is particularly preferred.

The thickness of the transparent protective film can be appropriately determined, and is generally about 1 to 100 μm from the viewpoints of workability such as strength and workability, and thin layer properties. In particular, it is preferably 1 to 80 μm, more preferably 3 to 60 μm.

In addition, if a transparent protective film is provided on both sides of the polarizing member, a transparent protective film made of the same polymer material may be used in the surface, and a transparent protective film made of a different polymer material may be used.

The transparent protective film may be provided with a functional layer such as a hard coat layer, an antireflection layer, an anti-adhesion layer, a diffusion layer, and an anti-glare layer, which is not adjacent to the polarizing member. Further, the functional layer such as the hard coat layer, the antireflection layer, the anti-adhesion layer, the diffusion layer, and the anti-glare layer may be provided on the transparent protective film itself, or may be separately provided as an individual different from the transparent protective film.

<Optical film>

The polarizing film of the present invention can be used as an optical film laminated with other optical layers when practical. The optical layer is not particularly limited, and for example, an optical layer used for forming a reflection plate or a semi-transmissive plate, a phase difference plate (including a wavelength plate of 1/2 or 1/4, etc.), a liquid crystal display device such as a viewing angle compensation film, or the like. It can be used in 1 layer or more. In particular, it is preferably a polarizing thin film of the present invention. a reflective polarizing film or a semi-transmissive polarizing film formed by a film re-reflecting plate or a semi-transmissive reflecting plate, an elliptically polarizing film or a circularly polarizing film which is formed by laminating a phase difference plate on a polarizing film, and laminated on the polarizing film A wide viewing angle polarizing film made of a viewing angle compensation film or a polarizing film formed by laminating a brightness enhancement film on a polarizing film.

The optical film in which the optical layer is laminated on the polarizing film can be formed by sequentially laminating in a manufacturing process such as a liquid crystal display device. However, in order to form an optical film in advance, it is excellent in quality stability and assembly work. It has the advantage of improving the manufacturing steps of a liquid crystal display device or the like. A suitable bonding method such as an adhesive layer can be used for the laminate. In the case of the above-mentioned polarizing film or other optical film, the optical axes can be appropriately arranged according to the purpose of the phase difference characteristic or the like.

The polarizing film described above and the optical film in which at least one polarizing film is laminated may be provided with an adhesive layer for subsequent bonding with other members such as a liquid crystal cell. The adhesive for forming the adhesive layer is not particularly limited, and an acrylic polymer, a polyoxymethylene polymer, a polyester, a polyurethane, a polyamide, a polyether, a fluorine-based or a rubber-based polymer can be suitably used. As a base polymer. In particular, it is preferred to use an acrylic pressure-sensitive adhesive which is excellent in optical transparency, exhibits excellent wettability and cohesiveness, and is excellent in weather resistance and heat resistance.

The adhesive layer can be provided on one side or both sides of the polarizing film or the optical film in such a manner that an overlapping layer of composition or type is different. Further, in the case of being disposed on both sides, the surface of the polarizing film or the optical film may be an adhesive layer having a different composition or type or thickness. The thickness of the adhesive layer can be used accordingly The purpose and the adhesion are appropriately determined, and are generally 1 to 500 μm, preferably 1 to 200 μm, and particularly preferably 1 to 100 μm.

For the exposed surface of the adhesive layer, for the purpose of preventing contamination between the actual use, the separator may be temporarily adhered and covered. Thereby, it is possible to prevent contact with the adhesive layer under normal operating conditions. As the separator, it is possible to use a suitable article according to the above-mentioned thickness conditions, and for example, a plastic film, a rubber sheet, a paper, a cloth, a non-woven fabric, a net, a foamed sheet or a metal foil, and the like can be used. The sheet is formed by coating with a suitable release agent such as polyoxymethylene or long-chain alkyl, fluorine or molybdenum sulfide.

<Image display device>

The polarizing film or optical film of the present invention is suitably used for the formation of various devices such as liquid crystal display devices. The formation of the liquid crystal display device can be carried out in accordance with conventional knowledge. In other words, the liquid crystal display device is generally formed by suitably assembling a liquid crystal cell, a polarizing film or an optical film, and a lighting system such as a required lighting device into a driving circuit or the like. In the present invention, in addition to using the polarizing film of the present invention or Other than the matter of the optical film, there is no particular limitation and it can be followed. As the liquid crystal cell, an optional form such as a TN type, an STN type, or a π type can be used.

It is possible to provide a liquid crystal display device in which a polarizing film or an optical film is disposed on one side or both sides of a liquid crystal cell, or a liquid crystal display device using a backlight or a reflecting plate as an illumination system. At this time, the polarizing film or the optical film of the present invention may be disposed on one side or both sides of the liquid crystal cell. When a polarizing film or an optical film is disposed on both sides, the same may be the same or different. In addition, when forming a liquid crystal display device, it can be in a suitable position A suitable member such as a diffusion plate, an antiglare layer, an antireflection film, a protective plate, a tantalum array, a lens array sheet, a light diffusing plate, or a backlight is disposed in one layer or two or more layers.

[Examples]

The embodiments of the present invention are described below, but the embodiments of the present invention are not limited thereto.

<Production of polarizer>

A polyvinyl alcohol film having an average polymerization degree of 2400 and a saponification degree of 99.9 mol% and a thickness of 75 μm was immersed in warm water of 30 ° C for 60 seconds to swell. Next, it was immersed in an aqueous solution of 0.3% by weight of iodine/potassium iodide (weight ratio = 0.5/8), which was extended to 3.5 times and the film was dyed. Thereafter, the solution was extended in a boric acid aqueous solution at 65 ° C so that the total stretching ratio was 6 times. After stretching, it was dried in an oven at 40 ° C for 3 minutes to obtain a PVA-based polarizer X (thickness: 23 μm).

<Transparent protective film>

Transparent protective film 1: a thickness of 60 μm of triethylene glycol cellulose film (water permeability 530g / m ² / 24h) without saponification. It is used in the case of corona treatment or the like (described as TAC in Table 1).

The transparent protective film 2: 100 parts by weight of the sulfiminated MS resin described in Production Example 1 of JP-A-2010-284840, and 0.62 parts by weight of a triazine-based ultraviolet absorber (trade name: T-712, manufactured by ADEKA Corporation) The resin pellets were prepared by mixing at 220 ° C in a 2-axis kneading machine. The obtained resin pellet was dried at 100.5 kPa and 100 ° C for 12 hours, and extruded from a T die at a die temperature of 270 ° C by a uniaxial extruder and formed into a film shape (thickness: 160 μm). The film was further extended in a conveyance direction (thickness: 80 μm) in a gas atmosphere of 150 ° C, and secondly, after applying an easy-adhesive agent containing an aqueous urethane resin, it was oriented perpendicular to the film transport direction in a gas atmosphere of 150 ° C. The direction was extended to obtain a transparent protective film 2 (referred to as acrylic acid in Table 1) having a thickness of 40 μm (humidity: 58 g/m ² /24 h).

<Transparency of transparent protective film>

The measurement of the moisture permeability is carried out in accordance with the moisture permeability test (the moisture permeable cup method) of JIS Z0208. The sample cut into a diameter of 60 mm was placed in a moisture permeable cup containing about 15 g of calcium chloride, and placed in a thermostat having a temperature of 40 ° C and a humidity of 90% RH to measure the weight increase of calcium chloride before and after standing for 24 hours. The moisture permeability (g/m ² /24h) can be determined.

<Total water absorption rate>

Using a curing adhesive for a polarizing film used in each of the examples, two sheets of glass separated by a gap of 100 μm were rubbed, and cured under the same active energy conditions as in the examples to prepare an adhesive layer (cured product) having a thickness of 100 μm. . Take this as a sample. The weight of the sample was set to (M1)g. Sample M1g was immersed in pure water at 23 ° C for 24 hours. Thereafter, the sample was taken out from pure water and wiped with a dry cloth, and the weight (M2) g of the sample was measured again within 1 minute. From this result, the overall water absorption rate was calculated by the following formula.

Formula: {(M2-M1)/M1}×100 (%)

<Storage Elasticity Coefficient>

The storage elastic modulus was measured using the dynamic viscoelasticity measuring apparatus RSAIII manufactured by TA INSTRUMENTS using the following measurement conditions.

Sample size: 10mm wide and 30mm long Clamping distance 20mm, measurement mode: stretching, weekly frequency: 1Hz, heating rate: 5 °C / minute

The dynamic viscoelasticity was measured as a measured value of the storage elastic modulus at 25 °C.

<Active energy ray>

As the active energy ray, a visible light (a metal halide lamp enclosed in gallium) irradiation device: Light HAMMER10 lamp manufactured by Fusion UV Systems, Inc.: V-tube peak illuminance: 1600 mW/cm 2 , integrated irradiation amount: 1000/mJ/ Cm ² (wavelength 380~440nm). Further, the illuminance of visible light was measured using a Sola-Check system manufactured by Solatell.

Examples 1 to 12 and Comparative Examples 1 to 3

(modulation of active energy ray hardening type adhesive)

According to the matching table described in Table 1, the components were mixed, and then KAYACURE-DETX-S (2,4-diethylthioxanthone; manufactured by Nippon Kayaku Co., Ltd.) and IRGACURE 907 (2-methyl-1-() were added. 4-methylthiophenyl)-2-morpholinylpropan-1-one (manufactured by BASF), 1.5 g and 3 g of each of 100 g of the radically polymerizable compound were added and stirred to obtain Examples 1 to 9 and The active energy ray-curable adhesive composition of Comparative Example 1.

(production of polarizing film)

On the transparent protective film, the active energy ray-curable adhesives of Examples 1 to 12 or Comparative Examples 1 to 3 were used in an MCD coater (Fuji Machinery Co., Ltd.) (groove shape: honeycomb shape, number of gravure rolls) : 1000 strips/inch, the number of revolutions of 140% / the line speed) was applied so as to have a thickness of 0.7 μm, and bonded to both sides of the polarizing member X by a roll press. Thereafter, the transparent protective film from the fit On the side (both sides) of the film, the visible light was applied to both surfaces by an active energy ray irradiation apparatus, and the active energy ray-curable adhesives of Example 1 and Comparative Example 1 were cured, and then dried by hot air at 70 ° C for 3 minutes. A polarizing film having a transparent protective film on both sides of the polarizing member is obtained. The line speed of the bonding was performed at 25 m/min.

The polarizing films obtained in the above examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 1.

<Adhesion force after water immersion (water resistance evaluation)>

The polarizing film was cut in a direction parallel to the extending direction of the polarizing member of 200 mm and a straight direction of 15 mm, and the polarizing film was immersed in water at 23 ° C for 3 hours, and then taken out and the polarizing film was taken within 30 minutes (non-dry state). Fitted with a glass plate. Next, the transparent protective film (acrylic acid or TAC) and the polarizing member were cut out by a cutting blade, and the protective film and the polarizing member were peeled off at a peeling speed of 300 mm/min in a direction of 90 degrees using a Tensilon tester, and the peeling was measured. Strength (N/15mm). The case where the peeling strength is 0.5 N/15 mm or more is ◎, the case of 0.1 N/15 mm or more is ○, and the case of less than 0.1 N/15 mm is ╳.

In Table 1, the radical polymerizable monomer is expressed as follows: HEAA: hydroxyethyl acrylamide, manufactured by Xingren Co., Ltd.; 4HBA; 4-hydroxybutyl acrylate, manufactured by Osaka Organic Chemical Co., Ltd.; ACMO: Acrylate Fulin, Xingren Co., Ltd.; TPGDA: propylene glycol diacrylate, manufactured by Toagosei Co., Ltd. (Aronix M-220); 1,9-NDA: 1,9-decanediol diacrylate, manufactured by Kyoeisha Chemical Co., Ltd. Metal alkoxides and metal chelate compounds are as follows: TC-750: ethyl acetoacetate ethyl chelate (organic group carbon number 6), manufactured by Matsumoto Fine Chemical Co., Ltd.; TC-100: titanium acetonitrile acetone (organic Carbon number of the base 5), manufactured by Matsumoto Fine Chemical Co., Ltd.; TA-30: octyloxy titanium (carbon number of organic base 8), manufactured by Matsumoto Fine Chemical Co., Ltd.; D-20: titanium butoxide (carbon number of organic base) 4), Shin-Etsu Silicone Co., Ltd.; ZA-65: butadiene zirconium (carbon number of organic base 4), manufactured by Matsumoto Fine Chemical Co., Ltd.; aluminum chelate M: alkyl acetoacetate diisopropyl ester (organic basis) Carbon number 4 or more), manufactured by Kawasaki Fine Chemical Co., Ltd.; vinyl ether compound: VEEA: 2-(2-vinyloxyethoxy)ethyl acrylate, manufactured by Nippon Shokubai Co., Ltd.; Generating agent expressed as: CPI-100P, San-Apro Co., Ltd..

Example 13~15

(modulation of active energy ray hardening type adhesive)

According to the matching table described in Table 2, the components were mixed, and KAYACURE-DETX-S (2,4-diethylthioxanthone; manufactured by Nippon Kayaku Co., Ltd.) and IRGACURE 907 (2-methyl-1-() were added. 4-methylthiophenyl)-2-morpholinylpropan-1-one (manufactured by BASF Corporation), 1.5 g and 3 g of the total of 100 g of the radically polymerizable compound were added and stirred, and Examples 13 to 15 were obtained. Active energy ray-curable adhesive composition.

(production of polarizing film)

In the above-mentioned transparent protective film, the active energy ray-curable adhesive of Examples 13 to 15 was an MCD coater (manufactured by Fuji Machinery Co., Ltd.) (groove shape: honeycomb shape, number of gravure rolls: 1000 strips/inch, The rotation speed of 140%/pairing speed was applied so as to have a thickness of 0.7 μm, and was bonded to both faces of the polarizing member X by a roll press. Thereafter, the visible light was applied to both sides from the side (both sides) of the bonded transparent protective film by an active energy ray irradiation device, and the active energy ray-curable adhesives of Example 1 and Comparative Example 1 were cured. The film was dried by hot air at 70 ° C for 3 minutes to obtain a polarizing film having a transparent protective film on both sides of the polarizing member. The line speed of the bonding was performed at 25 m/min.

In Table 2, the radical polymerizable monomer is expressed as follows: HEAA: hydroxyethyl acrylamide, manufactured by Xingren Co., Ltd.; ACMO: acryl oxime, Fahrenheit; 1,9-NDA: 1, 9-decanediol diacrylate, manufactured by Kyoeisha Chemical Co., Ltd.; M-5300: ω-carboxy-polycaprolactone (n≒2) monoacrylate (polymerizable compound having a polymerizable functional group and a carboxyl group), East Asia The metal alkoxide and the metal chelate compound are as follows: TA-21: titanium butoxide (carbon number 4 of organic group), manufactured by Matsumoto Fine Chemical Co., Ltd.; TC-750: ethyl chelating acetic acid ethyl chelate (organic carbon number 6), Matsumoto Fine TC-100: Titanium acetonitrile (carbon number of organic group 5), manufactured by Matsumoto Fine Chemical Co., Ltd.; and other components of the composition of the adhesive: UP-1190: manufactured by Toagosei Co., Ltd.

The polarizing films obtained in the above examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 2.

<Adhesion force after water immersion (water resistance evaluation)>

The polarizing film was cut in a direction parallel to the extending direction of the polarizing member of 200 mm and a straight direction of 15 mm, and the polarizing film was immersed in water at 23 ° C for 3 hours, and then taken out and the polarizing film was taken within 30 minutes (non-dry state). Fitted with a glass plate. Next, the transparent protective film (acrylic acid or TAC) and the polarizing member were cut out by a cutting blade, and the protective film and the polarizing member were peeled off at a peeling speed of 300 mm/min in a direction of 90 degrees using a Tensilon tester, and the peeling was measured. Strength (N/15mm). The case where the peeling strength is 0.5 N/15 mm or more is ◎, the case of 0.1 N/15 mm or more is ○, and the case of less than 0.1 N/15 mm is ╳.

Claims (20)

A hardening type adhesive composition for a polarizing film for use in a transparent protective film on at least one side of a polarizing member, characterized by containing an active energy ray hardening component, and being selected from a metal alkoxide and a metal chelate At least one organometallic compound in the group consisting of the compounds. The hardening type adhesive composition for a polarizing film according to claim 1, wherein the metal of the organometallic compound is titanium. The hardened adhesive composition for a polarizing film according to claim 1 or 2, which contains the metal alkoxide as the organometallic compound, and the metal alkoxide has an organic group having a carbon number of 6 or more. The curable adhesive composition for a polarizing film according to claim 1 or 2, which comprises the metal chelate compound as the organometallic compound, and the metal chelate compound has an organic group having 4 or more carbon atoms. The composition for a polarizing adhesive for a polarizing film according to any one of claims 1 to 4, wherein, when the total amount of the active energy ray-curable component is 100 parts by weight, the ratio of the organometallic compound is 0.05 to 9 by weight. Share. The cured adhesive composition for a polarizing film according to any one of claims 1 to 5, wherein the cured product obtained by curing the hardened adhesive composition is immersed in pure water at 23 ° C for 24 hours, The total water absorption of the formula is 10% by weight or less: Formula: {(M2-M1)/M1}×100 (%) However, M1: weight of hardened material before impregnation; M2: weight of hardened material after impregnation. The curable adhesive composition for a polarizing film according to any one of claims 1 to 6, wherein the active energy ray-curable component contains a radical polymerizable compound. The hardenable adhesive composition for a polarizing film according to claim 7, wherein the radically polymerizable compound contains a (meth) acrylamide derivative. The hardenable adhesive composition for a polarizing film according to claim 7 or 8, wherein the radical polymerizable compound contains a polyfunctional compound having at least two radically polymerizable functional groups. The hardenable adhesive composition for a polarizing film according to any one of claims 1 to 9, which further comprises a photopolymerization initiator. The hardenable adhesive composition for a polarizing film according to any one of claims 1 to 10, which further comprises a compound having a vinyl ether group. The hardening type adhesive composition for a polarizing film according to any one of claims 1 to 11, which further comprises a photoacid generator. The hardenable adhesive composition for a polarizing film according to any one of claims 1 to 12, wherein the cured resin obtained by curing the hardened adhesive composition has a storage elastic modulus of not less than 1.0 × 10 ⁷ Pa at 25 ° C. . A polarizing film which is provided with a transparent protective film on at least one side of a polarizing member and which is provided with an adhesive layer, wherein the adhesive layer is a hardening type adhesive for a polarizing film according to any one of claims 1 to 13. A cured layer of the composition is formed. The polarizing film of claim 14, wherein the thickness of the adhesive layer is 0.1~3μm. The polarizing film of claim 14 or 15, wherein the adhesive layer is immersed in pure water at 23 ° C for 24 hours, and the overall water absorption ratio expressed by the following formula is 10% by weight or less: Formula: {(M2-M1) / M1} × 100 (%) only, M1: weight of the cured product before impregnation; M2: weight of the cured product after impregnation. The polarizing film according to any one of claims 14 to 16, wherein the adhesive layer has a storage elastic modulus at 25 ° C of 1.0 × 10 ⁷ Pa or more. A method of producing a polarizing film according to any one of claims 14 to 17, characterized by comprising the step of coating a coating layer on at least one side of the polarizing member and the transparent protective film a curing adhesive composition for a polarizing film; a bonding step of bonding the polarizing member and the transparent protective film; and a step of irradiating active energy to a side of the polarizing member surface or a side of the transparent protective film surface The radiation is obtained by curing the active energy ray-curable adhesive composition to obtain the adhesive layer, and the polarizer and the transparent protective film are passed through the adhesive layer. An optical film characterized in that at least one of the polarizing films of any one of claims 14 to 17 is laminated. An image display device using the polarizing film of any one of claims 14 to 17 or the optical film of claim 19.