TWI692518B - Hardened adhesive for polarizing film, polarizing film, optical film and image display device - Google Patents

Abstract

The curable adhesive for polarizing film containing a curable component of the present invention, when the cured product of the polarizing film curable adhesive is immersed in pure water at 23° C. for 24 hours, the overall water absorption rate is expressed by the following formula 10% by weight or less, namely: overall water absorption rate (%) = formula: {(M2-M1)/M1}×100(%)

{However, in the above formula, M1 represents the weight of the hardened material before dipping, and M2 represents the weight of the hardened material after dipping}. The hardening adhesive for polarizing film is very good in the adhesion between the polarizer and the transparent protective film, and can meet the optical durability under the harsh environment of high temperature and high humidity, and even when immersed in water for a long time, It also has sufficient adhesion.

Description

Hardened adhesive for polarizing film, polarizing film, optical film and image display device Technical field

The present invention relates to a hardening adhesive for polarizing films, which is used to form the adhesive layer in a polarizing film in which a polarizer and a transparent protective film are laminated via an adhesive layer. In addition, the present invention relates to a polarizing film using the adhesive layer. The polarizing film can be used alone or as an optical film laminated with the polarizing film to form an image display device such as a liquid crystal display device (LCD), an organic EL display device, a CRT, and a PDP.

Background technique

In watches, mobile phones, PDAs, notebook personal computers, personal computer monitors, DVD players, TVs, etc., liquid crystal display devices are rapidly expanding in the market. The liquid crystal display device visualizes the polarization state using the switching of liquid crystal, and uses a polarizer according to its display principle. Especially in applications such as TV, high brightness, high contrast, and wide viewing angle are increasingly required, and in polarizing films, high transmittance, high polarization, and high color reproducibility are also required.

Due to its high transmittance and high degree of polarization, for example, iodine is adsorbed on polyvinyl alcohol (hereinafter, also simply referred to as "PVA") and extended. Iodine-based polarizers are generally the most widely used as polarizers. In general, the polarizing film uses the following polarizing film, that is, a transparent protective film is bonded to both sides of the polarizer by a so-called water-based adhesive dissolving a polyvinyl alcohol-based material in water (Patent Document 1 and Patent below Literature 2). The transparent protective film is made of triacetyl cellulose with high moisture permeability. When using the aforementioned water-based adhesive (so-called wet lamination), after the polarizer and the transparent protective film are bonded, a drying step must be performed.

On the other hand, it is currently revealed that there is an active energy ray hardening type Agent to replace the aforementioned water-based adhesive. When a polarizing film is manufactured using an active energy ray-curable adhesive, since a drying step is not necessary, the productivity of the polarizing film can be improved. For example, there is currently disclosed a radical polymerization type active energy ray-curable adhesive using N-substituted amide-based monomer as a curable component (Patent Document 3 and Patent Document 4 below). The aforementioned adhesive agent can exhibit excellent durability under severe environments under high humidity and high temperature, however, the fact is that an adhesive agent that can improve further adhesiveness and/or water resistance is still required on the market.

Also, focusing on the SP value (solubility parameter) of the hardening component, the It was previously disclosed that there is an active energy ray hardening type adhesive, which uses at least three kinds of radically polymerizable compounds with different SP values by a predetermined composition ratio, whereby an adhesive layer with improved durability and water resistance can be formed (below Refer to Patent Document 5).

Advanced technical literature Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2006-220732

Patent Document 2: Japanese Patent Laid-Open No. 2001-296427

Patent Document 3: Japanese Patent Laid-Open No. 2008-287207

Patent Document 4: Japanese Patent Laid-Open No. 2010-078700

Patent Literature 5: Japanese Patent Laid-Open No. 2012-144690

Summary of the invention

The active energy ray-curable adhesive disclosed in the aforementioned Patent Document 5 can satisfy the durability and water resistance of various transparent protective films used in the manufacture of polarizing films. However, although the polarized film prepared using the active energy ray-curable adhesive disclosed in Patent Document 5 can satisfy the water resistance (warm water immersion test) immersed in 60°C warm water for 6 hours, however, It requires further optical durability under severe environments under high temperature and high humidity. Furthermore, the polarizing film requires sufficient adhesion even when immersed in water for a long time.

The object of the present invention is to provide a hardening adhesive for polarizing film, which is very good in the adhesion between the polarizer and the transparent protective film, and can meet the optical durability under the harsh environment of high temperature and high humidity, while It has sufficient adhesion when immersed in water for a long time.

In addition, an object of the present invention is to provide a polarizing film which is formed by using an adhesive layer formed of a hardening adhesive for polarizing film, a transparent protective film is provided on a polarizer, and further, a polarizing film is used The optical film further provides an image display device using the aforementioned polarizing film or optical film.

In order to solve the above-mentioned problems, the inventors have repeatedly studied and found that the above-mentioned object can be achieved by the following hardening adhesive for polarizing film, so as to solve the present invention.

That is, the present invention relates to a hardening adhesive for polarizing films, which contains a curable component, and the hardening adhesive for polarizing films is immersed in a cured product obtained by hardening the hardening adhesive at 23°C. In the case of pure water for 24 hours, the overall water absorption rate expressed by the following formula is 10% by weight or less, that is, the overall water absorption rate (%)={(M2-M1)/M1}×100

{However, in the above formula, M1 represents the weight of the hardened material before dipping, and M2 represents the weight of the hardened material after dipping}.

The octanol/water partition coefficient (logPow value) of the hardening adhesive for polarizing film is preferably 1 or more.

The curable adhesive for polarizing film can be used as an active energy ray-curable adhesive when the curable component is an active energy ray-curable component. The curable component may contain a radical polymerizable compound. The aforementioned radical polymerizable compound preferably contains a (meth)acrylamide derivative. Furthermore, the radical polymerizable compound preferably contains a polyfunctional compound, and the polyfunctional compound has at least two radically polymerizable functional groups. Furthermore, the active energy ray-curable adhesive may further contain a photopolymerization initiator.

The hardening adhesive for polarizing film may further contain an acrylic oligomer (A).

The hardening type adhesive for polarizing films may further contain a photoacid generator (B).

The hardening-type adhesive for polarizing films may further contain a compound (C) containing any of alkoxy groups and epoxy groups. The compound (C) containing any of the aforementioned alkoxy and epoxy groups is preferably an alkoxy-containing compound (C1). Furthermore, the aforementioned alkoxy-containing compound (C1) is preferably an alkoxy-containing melamine compound.

In addition, the hardening adhesive for polarizing film may further contain an isocyanate compound (D).

The hardening type adhesive for polarizing film further contains a thermal polymerization initiator when the hardening component is a thermosetting component, and thus can be used as a thermosetting adhesive.

In addition, the present invention relates to a polarizing film in which at least one side of a polarizer is provided with a transparent protective film via an adhesive layer, and the adhesive layer is a cured product of the hardening adhesive for polarizing film Layer formation.

In the polarizing film, the thickness of the adhesive hardened layer is preferably 0.1 to 3 μm.

Furthermore, the present invention relates to an optical film in which at least one polarizing film is laminated.

Furthermore, the present invention relates to an image display device using the polarizing film or the optical film.

The hardening type adhesive for polarizing film of the present invention makes the hardening The overall water absorption of the cured product obtained by curing the type adhesive is 10% by weight or less. This overall water absorption rate shows that the water absorption when the adhesive layer is formed from the hardened layer obtained from the hardening adhesive for polarizing film of the present invention is very low. Therefore, a polarizing film provided with a transparent protective film on the polarizer through the adhesive layer formed by the hardened layer is very good in adhesion between the polarizer and the transparent protective film layer, and can meet high temperature and high humidity The optical durability under the harsh environment.

For example, a polarizing film having a hardened layer (adhesive layer) formed using the hardening type adhesive for polarizing film of the present invention is optically durable even under severe humidified environment (85°C×85%RH) The performance (humidification durability test) is also good. Therefore, even when the polarizing film of the present invention is placed under the severe humidification environment described above, it can suppress the decrease (change) in the transmittance and polarization degree of the polarizing film. In addition, the polarizing film of the present invention can suppress the decrease in adhesion even under severe environments such as being immersed in water, and can provide a polarizing film having sufficient adhesion even when immersed in water for a long time.

Forms for carrying out the invention

<overall water absorption rate>

The hardening-type adhesive for polarizing films of the present invention has an overall water absorption of 10% by weight or less as measured by immersing the hardened product obtained by hardening the hardening-type adhesive in pure water at 23° C. for 24 hours. When the polarizing film is placed in the harsh environment of high temperature and high humidity (85℃/85%RH, etc.), it has been transparent The moisture of the over-transparent protective film and the adhesive layer penetrates into the polarizer, and the cross-linked structure is hydrolyzed, whereby the orientation of the dichroic pigment is disordered, and the optical durability such as increased transmittance and decreased polarization degree is deteriorated. By setting the overall water absorption of the adhesive layer to 10% by weight or less, the movement of water toward the polarizer can be suppressed when the polarizing film is placed in a severe high temperature and high humidity environment, and the transmittance of the polarizer can be suppressed from rising and polarizing Degrees decrease. For the adhesive layer of the polarizing film, from the viewpoint of making the optical durability in a severe environment under high temperature more favorable, the overall water absorption rate is preferably 5% by weight or less, and more preferably 3% by weight or less Furthermore, it is preferably 1.5% by weight or less, and most preferably 1% by weight or less. On the other hand, when the polarizer and the transparent protective film are bonded, the polarizer will maintain a certain amount of moisture, and when the hardening adhesive contacts the moisture contained in the polarizer, it may cause appearance defects such as collapse and bubbles. . In order to suppress poor appearance, the hardening type adhesive should preferably absorb a certain amount of moisture. More specifically, the overall water absorption rate is preferably 0.01% by weight or more, and more preferably 0.05% by weight or more. Specifically, the aforementioned overall water absorption rate is measured by the water absorption rate test method disclosed in JIS K 7209.

The hardening adhesive for polarizing film of the present invention is preferably octanol/water The partition coefficient (hereinafter referred to as logPow value) is high. The so-called logPow value is an index indicating the lipophilicity of the substance, and means the logarithmic value of the partition coefficient of octanol/water. A high logPow means it is lipophilic, that is, it means low water absorption. The logPow value can be measured (the flask shaking method disclosed in JIS-Z-7260), however, it can also be calculated by calculation according to the structure of each compound that is a constituent component (hardening component, etc.) of the hardening adhesive for polarizing film To figure it out. In this manual, Chem manufactured by CambridgeSoft is used The logPow value calculated by Draw Ultra.

Based on the aforementioned calculation value, the logPow value of the hardening type adhesive for polarizing film in the present invention can be calculated by the following formula.

LogPow=Σ(logPowi×Wi) of hardening adhesive

logPowi: the logPow value of each component of the hardening adhesive

Wi: (mole number of component i)/(total moles of each component of hardening adhesive)

In the foregoing calculation, among the components of the hardening adhesive, components such as a polymerization initiator or a photoacid generator that do not form a skeleton of the cured product (adhesive layer) are deducted from the components in the foregoing calculation. The logPow value of the hardening adhesive for polarizing film of the present invention is preferably 1 or more, more preferably 1.5 or more, and most preferably 2 or more. With this, the subsequent water resistance or humidification durability can be improved. On the other hand, the logPow value of the hardening adhesive for polarizing film of the present invention is usually 8 or less, and preferably 5 or less, and more preferably 4 or less. If the logPow value is too high, as described above, since appearance such as collapse or bubbles is likely to occur, it is less desirable.

In addition, there is no particular limitation on the method of making the overall water absorption rate of 10% by weight or less in the present invention. However, when the hardening adhesive for polarizing film is a composition containing a plurality of components, by selecting each component, The overall water absorption rate can be controlled within the aforementioned range. For example, when the hardening adhesive for polarizing film is an adhesive composition containing a plurality of components, by adjusting to reduce the ratio of components with a logPow value of 1 or less in the adhesive composition, the whole The water absorption rate is controlled within the aforementioned range. To adjust the overall water absorption in the present invention to 10% by weight or less, for example In other words, it can be performed by controlling the logPow value of the hardening adhesive for polarizing film to 1 or more.

<hardening shrinkage>

In addition, since the curable adhesive for polarizing film of the present invention has a curable component, when the curable adhesive is cured, curing shrinkage usually occurs. The curing shrinkage rate is an index showing the curing shrinkage ratio when the adhesive layer is formed from the hardening adhesive for polarizing film. If the curing shrinkage of the adhesive layer increases, interface strain will occur when the adhesive layer is formed by hardening the polarizing film hardening adhesive, and it is desirable to suppress the occurrence of adhesive defects. From the aforementioned viewpoint, the curing shrinkage rate of the cured product obtained by curing the curing adhesive for polarizing film of the present invention is preferably 10% or less. Preferably, the hardening shrinkage rate is small, and the hardening shrinkage rate is preferably 8% or less, and more preferably 5% or less. The aforementioned hardening shrinkage rate is measured by the method disclosed in JP-A-2013-104869. Specifically, it is measured by a method using a hardening shrinkage sensor manufactured by SENTEC Corporation as disclosed in the examples.

<hardening ingredient>

The curable adhesive for polarizing film of the present invention contains a curable component. The curable component can be appropriately selected so that the cured product satisfies the aforementioned overall water absorption rate.

Curable components can be roughly divided into active energy ray curing type and thermosetting type such as electron beam curing type, ultraviolet curing type and visible light curing type. Furthermore, ultraviolet curing type and visible light curing type adhesives can be divided into radical polymerization curing type adhesives and cationic polymerization type adhesives. Yu Ben In the invention, the active energy line with a wavelength range of 10 nm to less than 380 nm is marked as ultraviolet rays, and the active energy line with a wavelength range of 380 nm to 800 nm is marked as visible light. The curable component of the radical polymerization hardening type adhesive can be used as the curable component of the thermosetting type adhesive.

<1: Radical polymerization hardening type adhesive>

For example, the aforementioned curable component can be exemplified by radical polymerizable compounds used in radical polymerization hardening type adhesives. Examples of the radically polymerizable compound include compounds having a radically polymerizable functional group having a carbon-carbon double bond such as (meth)acryloyl group and vinyl group. As these hardening components, any of a monofunctional radical polymerizable compound or a bifunctional or higher polyfunctional radical polymerizable compound can be used. Moreover, these radically polymerizable compounds can be used individually by 1 type or in combination of 2 or more types. For example, these radically polymerizable compounds are suitably compounds having a (meth)acryloyl group. In the present invention, the term "(meth)acryloyl" means propenyl and/or methacryl, and "(meth)" has the same meaning as below.

"Monofunctional Radical Polymerizable Compound"

For example, examples of the monofunctional radical polymerizable compound include (meth)acrylamide derivatives having a (meth)acrylamide group. The (meth)acrylamide derivative is preferable in terms of securing the adhesion to the polarizer or various transparent protective films, and in terms of fast polymerization speed and excellent productivity. For example, specific examples of (meth)acrylamide derivatives include N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N -Diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hexyl(meth)acrylamide, etc. contain N -Alkyl (Meth) acrylamide derivatives; N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N-hydroxymethyl-N-propane (meth) acryl N-hydroxyalkyl-containing (meth)acrylamide derivatives such as amides; aminemethyl (meth)acrylamide, amine ethyl (meth)acrylamides containing N-aminoalkyl ( (Meth)acrylamide derivatives; N-methoxymethacrylamide, N-ethoxymethacrylamide and other (meth)acrylamide derivatives containing N-alkoxy; mercaptomethyl N-mercaptoalkyl-containing (meth)acrylamide derivatives and the like, such as (meth)acrylamide and mercaptoethyl (meth)acrylamide. In addition, for example, the heterocyclic ring-containing (meth)acrylamide derivatives in which the nitrogen atom of the (meth)acrylamide group forms a heterocyclic ring include N-propenyl morpholine, N-acryl amide Piperidine, N-methacryloyl piperidine, N-propenyl pyrrolidine, etc.

Among the aforementioned (meth)acrylamide derivatives, if the polarizer is used Or from the viewpoint of the adhesion of various transparent protective films, it is also preferably a (meth)acrylamide derivative containing N-hydroxyalkyl, especially N-hydroxyethyl (meth)acrylamide .

In addition, for example, the monofunctional radical polymerizable compound may include various (meth)acrylic acid derivatives having (meth)acryloyloxy groups. Specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate , 2-methyl-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-di Methylbutyl (meth)acrylate, n-hexyl (meth)acrylate, hexadecyl (meth)acrylic acid Ester, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-2-propylpentyl (meth)acrylate, n-octadecyl (meth) (Meth)acrylic acid (C 1-20) alkyl esters such as acrylate.

Also, for example, the aforementioned (meth)acrylic acid derivative can be exemplified Such as: cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate and other cycloalkyl (meth) acrylate; benzyl (meth) acrylate and other aralkyl (meth) acrylate; 2-isobornyl (meth)acrylate, 2-norbornyl methyl (meth)acrylate, 5-norbornen-2-yl-methyl (meth)acrylate, 3-methyl- 2-norbornyl methyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentyl (meth) ) Polycyclic (meth)acrylates such as acrylate; 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxymethoxy Ethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxyethyl (meth)acrylate, alkylbenzene Oxypolyethylene glycol (meth)acrylates and the like (meth)acrylates containing alkoxy or phenoxy groups.

In addition, the (meth)acrylic acid derivatives include, for example, 2-hydroxyethyl (Meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl ( Methacrylates, 6-hydroxyhexyl (meth)acrylates, 8-hydroxyoctyl (meth)acrylates, 10-hydroxydecyl (meth)acrylates, 12-hydroxylauryl (meth) Hydroxyalkyl (meth)acrylates such as acrylates or [4-(hydroxymethyl)cyclohexyl]methacrylate, cyclohexanedimethanol mono (meth)acrylate, 2-hydroxy-3-phenoxy Hydroxy-containing (meth)acrylates such as propyl (meth)acrylate; glycidyl oxide (Meth)acrylates containing epoxy groups such as (meth)acrylate, 4-hydroxybutyl (meth)acrylate epoxypropyl ether; 2,2,2-trifluoroethyl (methyl ) Acrylate, 2,2,2-trifluoroethylethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropentyl ( (Meth) acrylate, heptafluorodecyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate and other halogen-containing (meth) acrylate; dimethylamino ethyl Alkyl (meth) acrylate and other alkylamino alkyl (meth) acrylate; 3-oxetanyl methyl (meth) acrylate, 3-methyl-oxetanyl methyl (Meth)acrylate, 3-ethyl-oxetanyl methyl (meth)acrylate, 3-butyl-oxetanyl methyl (meth)acrylate, 3- Hexyl-oxetanyl methyl (meth)acrylates and other (meth)acrylates containing oxetane groups; tetrahydrofurfuryl (meth)acrylates, butyrolactone (methyl) Acrylates and the like (meth)acrylates having heterocycles, hydroxytrimethylacetic acid neopentyl glycol (meth)acrylic acid adducts, p-phenylphenol (meth)acrylates and the like.

In addition, the monofunctional radical polymerizable compound may be exemplified by: (A Base) acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid and other monomers containing carboxyl groups.

Also, for example, monofunctional radical polymerizable compounds can be listed Examples include: N-vinylpyrrolidone, N-vinyl-ε-caprolactam, methylvinylpyrrolidone, and other vinylamide vinyl monomers; vinylpyridine, vinylpiperidone, Nitrogen-containing heterocyclic vinyl monomers such as vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, etc.

In addition, monofunctional radical polymerizable compounds can be used with activity Radical polymerizable compounds of methylene. A radical polymerizable compound having an active methylene group is a compound having an active double bond group such as a (meth)acryloyl group at the terminal or molecule and having an active methylene group. For example, the active methylene group can be exemplified by: acetoacetoxy, alkoxypropanedioxy, cyanoacetoxy, etc. The aforesaid active methylene group is preferably acetyl acetyl group. For example, specific examples of the radically polymerizable compound having an active methylene group include: 2-acetoacetoxyethyl (meth)acrylate, 2-acetoxyacetoxypropyl ( Methacrylic acid ester, 2-acetoxyethyloxy-1-methylethyl (meth)acrylate, etc. Acetylacetoxyalkyl (meth)acrylate; 2-ethoxypropanedi Acetyloxyethyl (meth)acrylate, 2-cyanoacetoxyethyl (meth)acrylate, N-(2-cyanoacetoxyethyl)acrylamide, N- (2-Propionylacetoxybutyl)acrylamide, N-(4-acetylacetoxymethylbenzyl)acrylamide, N-(2-acetylacetoacetamide) Radicals) acrylamide etc. The free-radical polymerizable compound having an active methylene group is preferably acetyl acetyl oxyalkyl (meth) acrylate.

"Multifunctional Radical Polymerizable Compound"

In addition, for example, the bifunctional or higher polyfunctional radical polymerizable compound may include tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol Di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol diacrylate, 2-ethyl-2-butylpropanediol di(meth)acrylic acid Ester, 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(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(methyl) Acrylate, cyclic trimethylolpropane formal (meth)acrylate, dioxanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, neopentyl alcohol Tri (meth) acrylate, neopentaerythritol tetra (meth) acrylate, di neopentaerythritol penta (meth) acrylate, di neopentaerythritol hexa (meth) acrylate, EO modified diglycerol Ester of (meth)acrylic acid and polyol, such as tetra(meth)acrylate, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl] stilbene. Specific examples include: ARONIX M-220, M-306 (manufactured by East Asia Synthesizer), LIGHT ACRYLATE 1, 9ND-A (manufactured by Kyoeisha Chemical Company), LIGHT ACRYLATE DGE-4A (manufactured by Kyoeisha Chemical Company), LIGHT ACRYLATE DCP-A (manufactured by Kyoeisha Chemical Co., Ltd.), SR-531 (manufactured by Sadoomer), CD-536 (manufactured by Sadoomer), etc. Moreover, various epoxy (meth)acrylates, urethane (meth)acrylates, polyester (meth)acrylates, various (meth)acrylate monomers, etc. are mentioned as needed. .

In controlling the water absorption rate of the aforementioned hardened material, in addition, in meeting the polarized light In terms of optical durability of the film under severe humidified environments, it is desirable that the radically polymerizable compound contains the aforementioned multifunctional radically polymerizable compound. Among the aforementioned multifunctional radical polymerizable compounds, those with a high logPow value are also preferred. The logPow value of the radical polymerizable compound is preferably 2 or more, more preferably 3 or more, and most preferably 4 or more.

For example, a radical polymerizable compound with a high logPow value can Examples include: alicyclic (meth)acrylates such as tricyclodecane dimethanol di(meth)acrylate (logPow=3.05), isobornyl (meth)acrylate (logPow=3.27); 1,9- Nonanediol di(meth)acrylate (logPow=3.68), 1,10-decanediol diacrylate (logPow=4.10) and other long-chain aliphatic (meth)acrylate; hydroxytrimethylacetic acid neopentyl glycol (meth)acrylic acid adduct (logPow=3.35), 2-ethyl-2-butylpropanediol di(meth)acrylate (logPow=3.92) and other multi-branched (meth)acrylates; bisphenol A di(meth)acrylate ( logPow=5.46), bisphenol A ethylene oxide 4 mole adduct di(meth)acrylate (logPow=5.15), bisphenol A propylene oxide 2 mole adduct di(meth)acrylate (logPow=6.10), bisphenol A propylene oxide 4 mole adduct di(meth)acrylate (logPow=6.43), 9,9-bis[4-(2-(meth)acryloyloxy) (Ethoxy) phenyl] stilbene (logPow = 7.48), p-phenylphenol (meth) acrylate (logPow = 3.98) and other aromatic ring-containing (meth) acrylate.

If it is combined with polarizers or various transparent protective films From the viewpoint of the optical durability in the harsh environment and the harsh environment, it is preferable to use a monofunctional radically polymerizable compound and a polyfunctional radically polymerizable compound in combination with the radically polymerizable compound. Generally speaking, it is preferable to use a monofunctional radical polymerizable compound at a ratio of 3 to 80% by weight and a polyfunctional radical polymerizable compound at 20 to 97% by weight relative to 100% by weight of the radical polymerizable compound.

<Appearance of free radical polymerization hardening type adhesive>

When the curable adhesive for polarizing film of the present invention is used as a curable component as an active energy ray curable component, it can be used as an active energy ray curable adhesive, and when the curable component is a thermosetting component When used, it can be used as a thermosetting adhesive. When the active energy ray-curable adhesive described above uses electron beams or the like for active energy rays, the active The energy curable adhesive does not need to contain a photopolymerization initiator. However, when using ultraviolet rays or visible rays for the active energy ray, it is preferable to contain a photopolymerization initiator. On the other hand, when the curable component of the adhesive is used as a thermosetting component, the adhesive preferably contains a thermal polymerization initiator.

"Photopolymerization Initiator"

(thioxanthone)、2-氯9-氧硫

、2-甲基9-氧硫

、2,4-二甲基9-氧硫

、異丙基9-氧硫

、2,4-二氯9-氧硫

、2,4-二乙基9-氧硫

、2,4-二異丙基9-氧硫

、十二基9-氧硫

等9-氧硫

系化合物；樟腦醌；鹵化酮；醯基氧化膦；醯基膦酸酯等。於光聚合引發劑中，亦宜為 logPow值高者。光聚合引發劑並未包含於偏光薄膜用硬化型接著劑之logPow值之計算中之成分，然而，光聚合引發劑之logPow值宜為1以上，且更宜為2以上，最宜為3以上。 When a radically polymerizable compound is used, the photopolymerization initiator can be appropriately selected according to the active energy ray. When curing by ultraviolet rays or visible rays, a photopolymerization initiator that splits ultraviolet rays or visible rays is used. For example, the aforementioned photopolymerization initiator may include diphenyl ethyl ketone, diphenyl ketone, benzoyl benzoic acid, 3,3'-dimethyl-4-methoxydiphenyl ketone, etc. Phenyl ketone compounds; 4-(2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-dimethylacetophenone, 2-methyl Aromatic ketone compounds such as -2-hydroxyphenylacetone and α-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-bis Acetophenone compounds such as ethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinepropane-1; benzoin methyl ether, benzoin Benzoin ether compounds such as diethyl ether, benzoin isopropyl ether, benzoin butyl ether, anisein methyl ether, etc.; aromatic ketal compounds such as diphenyl ethyl ketone dimethyl ketal; 2-naphthalene Aromatic sulfonyl chloride compounds such as sulfonyl chloride; photoactive oxime compounds such as 1-benzophenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; 9-oxosulfur

(thioxanthone), 2-chloro 9-oxysulfur

, 2-methyl 9-oxysulfur

, 2,4-Dimethyl 9-oxysulfur

, Isopropyl 9-oxysulfur

, 2,4-Dichloro 9-oxysulfur

, 2,4-Diethyl 9-oxysulfur

, 2,4-Diisopropyl 9-oxysulfur

, Dodecyl 9-oxysulfur

9-oxygen sulfur

Compounds; camphorquinone; halogenated ketones; acylphosphine oxide; acylphosphonate, etc. Among photopolymerization initiators, those with a high logPow value are also preferred. The photopolymerization initiator is not included in the calculation of the logPow value of the hardening adhesive for polarizing film, however, the logPow value of the photopolymerization initiator is preferably 1 or more, more preferably 2 or more, and most preferably 3 or more .

Relative to the total content of hardening components (radical polymerizable compounds) The amount is 100 parts by weight, and the blending amount of the aforementioned photopolymerization initiator is 20 parts by weight or less. The blending amount of the photopolymerization initiator is preferably 0.01 to 20 parts by weight, and more preferably 0.05 to 10 parts by weight, and further 0.1 to 5 parts by weight.

In addition, it contains a radically polymerizable compound as a hardening component Visible light curing type When using the curing type adhesive for polarizing film of the present invention, it is particularly preferable to use a photopolymerization initiator with high sensitivity to light of 380 nm or more. The photopolymerization initiator having high sensitivity to light of 380 nm or more will be described later.

(式中，R¹及R²表示-H、-CH₂CH₃、-iPr或Cl，且R¹及R²可相同或不同)，或併用藉由一般式(1)所表示之化合物與後述對380nm以上之光為高感度之光聚合引發劑。相較於單獨使用對380nm以上之光為高感度之光聚合引發劑時，使用藉由一般式(1)所表示之化合物時接著性優異。於藉由一般式(1)所表示之化合物中，亦特別宜為R¹及R²為-CH₂CH₃之二乙基9- 氧硫

。相對於硬化性成分之全量100重量份，接著劑中藉由一般式(1)所表示之化合物之組成比率宜為0.1~5重量份，且更宜為0.5~4重量份，進而宜為0.9~3重量份。 The aforementioned photopolymerization initiator is preferably used alone as the compound represented by the following general formula (1):

(In the formula, 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), or a compound represented by general formula (1) and The photopolymerization initiator that is highly sensitive to light above 380 nm will be described later. The compound represented by the general formula (1) is superior in adhesion when the photopolymerization initiator with high sensitivity to light of 380 nm or more is used alone. Among the compounds represented by the general formula (1), diethyl 9-oxysulfur wherein R ¹ and R ² are -CH ₂ CH ₃ is also particularly preferred

. The composition ratio of the compound represented by the general formula (1) in the adhesive is preferably 0.1 to 5 parts by weight, more preferably 0.5 to 4 parts by weight, and further preferably 0.9 ~3 parts by weight.

Moreover, if necessary, it is preferable to add a polymerization initiation aid. Polymerization initiator Examples of the agent include: triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, Isoamyl 4-dimethylaminobenzoate, etc., particularly preferably ethyl 4-dimethylaminobenzoate. When using a polymerization initiation aid, the addition amount is usually 0 to 5 parts by weight, preferably 0 to 4 parts by weight, and most preferably 0 to 3 parts by weight relative to 100 parts by weight of the total amount of the hardening component.

In addition, if necessary, a known photopolymerization initiator may be used in combination. due to The transparent protective film with UV absorption ability will not transmit light below 380nm. Therefore, the photopolymerization initiator should be a photopolymerization initiator with high sensitivity to light above 380nm. Specific examples include 2-methyl-1-(4-methylthiophenyl)-2-morpholinepropane-1-one and 2-benzyl-2-dimethylamino-1-( 4-morpholinylphenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)benzene Group]-1-butanone, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzyl)-phenylphosphine Oxides, bis(η 5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl) titanium, etc.

(式中，R³、R⁴及R⁵表示-H、-CH₃、-CH₂CH₃、-iPr或Cl，且R³、R⁴及R⁵可相同或不同)。藉由一般式(2)所表示之化合物可適當地使用亦屬於市售品的2-甲基-1-(4-甲硫基苯基)-2-嗎啉丙烷-1-酮(商品名：IRGACURE907，製造者：BASF)。除此之外，2-苄基-2-二甲胺基-1-(4-嗎啉苯基)-丁酮-1(商品名：IRGACURE369，製造者：BASF)、2-(二甲胺基)-2-[(4-甲基苯基)甲基]-1-[4-(4-嗎啉基)苯基]-1-丁酮(商品名：IRGACURE379，製造者：BASF)由於感度高，因此較為理想。 In particular, in addition to the photopolymerization initiator of general formula (1), it is more preferable to use a compound represented by the following general formula (2):

(In the formula, 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 general formula (2), 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (trade name) which is also commercially available can be suitably used : IRGACURE907, manufacturer: BASF). In addition, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1 (trade name: IRGACURE369, manufacturer: BASF), 2-(dimethylamine Yl)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (trade name: IRGACURE379, manufacturer: BASF) The sensitivity is high, so it is ideal.

<Free radical polymerizable compound (a1) with active methylene group and free radical polymerization initiator (a2) with hydrogen abstraction function>

Among the aforementioned active energy ray-curable adhesives, when the radical polymerizable compound uses a radical polymerizable compound (a1) having an active methylene group, it should be combined with a radical polymerization initiator (a2) having a hydrogen abstraction effect And use. With the aforementioned structure, even after taking out from a high-humidity environment or water (non-dry state), the adhesion of the adhesive layer of the polarizing film can be significantly improved. This reason is not clear, however, the following reasons are generally considered. That is, the radically polymerizable compound (a1) having an active methylene group is polymerized together with other radically polymerizable compounds constituting the adhesive layer and taken into the main chain and/or side of the base polymer in the adhesive layer Chain and form an adhesive layer. In the aforementioned polymerization process, if a radical polymerization initiator (a2) having a hydrogen abstraction function is present, a radical polymerizable compound (a2) having an active methylene group that forms the base polymer of the adhesive layer will be formed. Hydrogen, and generate free radicals in the methylene group. Moreover, the free radical methylene The base reacts with the hydroxyl group of the polarizer such as PVA and forms a covalent bond between the adhesive layer and the polarizer. As a result, it is generally speculated that even in a non-dry state, the adhesion of the adhesive layer of the polarizing film can be significantly improved.

系自由基聚合引發劑、二苯基酮系自由基聚合引發劑等。前述自由基聚合引發劑(a2)宜為9-氧硫

系自由基聚合引發劑。舉例言之，9-氧硫

系自由基聚合引發劑可列舉如：藉由前述一般式(1)所表示之化合物。舉例言之，藉由一般式(1)所表示之化合物之具體例可列舉如：9-氧硫

、二甲基9-氧硫

、二乙基9-氧硫

、異丙基9-氧硫

、氯9-氧硫

等。 於藉由一般式(1)所表示之化合物中，亦特別宜為R¹及R²為-CH₂CH₃之二乙基9-氧硫

。 In the present invention, for example, the radical polymerization initiator (a2) having a hydrogen abstraction effect can be exemplified by: 9-oxysulfur

Radical polymerization initiators, diphenyl ketone radical polymerization initiators, etc. The aforementioned radical polymerization initiator (a2) is preferably 9-oxysulfur

It is a radical polymerization initiator. For example, 9-oxosulfur

Examples of the radical polymerization initiator include compounds represented by the general formula (1). For example, specific examples of the compound represented by the general formula (1) include: 9-oxysulfur

Dimethyl 9-oxysulfur

, Diethyl 9-oxysulfur

, Isopropyl 9-oxysulfur

, Chlorine 9-oxygen sulfur

Wait. Among the compounds represented by the general formula (1), diethyl 9-oxysulfur wherein R ¹ and R ² are -CH ₂ CH ₃ is also particularly preferred

.

In the aforementioned active energy ray hardening type adhesive, when containing When the radically polymerizable compound (a1) of the active methylene group and the radical polymerization initiator (a2) having a hydrogen abstraction function, when the total amount of the curable component is 100% by weight, it is preferable to contain the aforementioned active methylene group The radical polymerizable compound (a1) is 1 to 50% by weight, and the total amount of the curable component is 100 parts by weight, and contains 0.1 to 10 parts by weight of the radical polymerization initiator (a2).

As mentioned above, in the present invention, the free radicals with hydrogen abstraction function In the presence of the polymerization initiator (a2), the methylene group of the radically polymerizable compound (a1) having an active methylene group generates radicals, and the aforementioned methylene group reacts with the hydroxyl group of the polarizer such as PVA to form a Price key. Therefore, in order to generate free radicals for the methylene group of the radical polymerizable compound (a1) having an active methylene group, and When the aforementioned covalent bond is sufficiently formed, when the total amount of the hardenable component is 100% by weight, it is preferable to contain 1 to 50% by weight of the radically polymerizable compound (a1) having an active methylene group, and more preferably 3 ~30% by weight. In order to sufficiently improve the water resistance and the adhesion in the non-dry state, the radical polymerizable compound (a1) having an active methylene group is preferably made 1% by weight or more. On the other hand, if it exceeds 50% by weight, the hardening of the adhesive layer may occur. Furthermore, the radical polymerization initiator (a2) having a hydrogen abstraction effect preferably contains 0.1 to 10 parts by weight relative to 100 parts by weight of the total amount of the hardenable component, and further preferably contains 0.3 to 9 parts by weight. In order to sufficiently perform the hydrogen abstraction reaction, it is preferable to use 0.1 parts by weight or more of the radical polymerization initiator (a2). On the other hand, if it exceeds 10 parts by weight, it may not be completely dissolved in the adhesive.

"Thermal Polymerization Initiator"

The thermal polymerization initiator is preferably one that does not start polymerization by thermal cracking when the adhesive layer is formed. For example, the thermal polymerization initiator is preferably a 10-hour half-life temperature of 65 ℃ or more, and further 75 ~ 90 ℃. In addition, the half-life is an index indicating the decomposition rate of the polymerization initiator and refers to the time until the remaining amount of the polymerization initiator constitutes half. The decomposition temperature used to obtain the half-life at any time or the half-life time at any temperature is disclosed in the manufacturer's catalog, etc., for example, in the "Organic Peroxide Catalog 9th Edition (2003 May)) etc.

For example, the thermal polymerization initiator can be exemplified by: Laurel peroxide Acyl (10-hour half-life temperature: 64°C), Benzoyl peroxide (10-hour half-life temperature: 73°C), 1,1-bis(t-butoxyperoxy)-3,3,5-trimethyl Cyclohexane (10-hour half-life temperature: 90°C), bis(2-ethylhexyl) peroxydicarbonate (10-hour half-life temperature: 49°C), bis(4-t-butylcyclohexyl) peroxydicarbonate, di-sec-butylperoxydicarbonate (10-hour half-life temperature: 51°C), t-butane Peroxyneodecanoate (10-hour half-life temperature: 48°C), t-hexaperoxytrimethyl acetate, t-butylperoxytrimethyl acetate, dilauryl peroxide (10 hours Half-life temperature: 64°C), di-n-octyl peroxide, 1,1,3,3-tetramethylbutoxyperoxy-2-ethylhexanoate (10-hour half-life temperature: 66°C), di( 4-methylbenzyl peroxide), dibenzoyl peroxide (10-hour half-life temperature: 73°C), t-butyl peroxyisobutyrate (10-hour half-life temperature: 81°C), Organic peroxides such as 1,1-di(t-hexaperoxy)cyclohexane.

In addition, for example, the thermal polymerization initiator may include: 2,2'-azobisisobutyronitrile (10 hour half-life temperature: 67°C), 2,2'-azobis(2-methylbutyronitrile ) (10 hour half-life temperature: 67°C), 1,1-azobis-cyclohexane-1-carbonitrile (10 hour half-life temperature: 87°C) and other azo compounds.

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

<2: Cationic polymerization hardening type adhesive>

Examples of the hardening component of the cationic polymerization hardening type adhesive include compounds having epoxy groups or oxetanyl groups. The compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known hardenable epoxy compounds can be used. Examples of the ideal epoxy compound include compounds having at least two epoxy groups and at least one aromatic ring in the molecule (aromatic epoxy compounds), or having A compound having at least two epoxy groups and at least one of which is formed between two adjacent carbon atoms constituting an alicyclic ring (alicyclic epoxy compound), etc.

<Photo cationic polymerization initiator>

Since the cationic polymerization hardening type adhesive contains the epoxy compound and the oxetane compound described above as hardening components, and these are hardened by cationic polymerization, a photo-cationic polymerization initiator is blended. The photo-cationic polymerization initiator generates cationic species or Lewis acid by irradiation of active energy rays such as visible rays, ultraviolet rays, X-rays, and electron rays, and starts the polymerization reaction of epoxy groups or oxetanyl groups.

<other ingredients>

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

<Acrylic oligomer (A)>

In addition to the curable component of the radical polymerizable compound, the active energy ray-curable adhesive of the present invention may contain an acrylic oligomer (A) composed of polymerized (meth)acrylic monomers. Since the active energy ray-curable adhesive contains an acrylic oligomer (A), the curing shrinkage when the active energy ray is irradiated to the adhesive and hardens can be reduced, and the adhesive, polarizer, transparent protective film, etc. can be reduced The interface stress of the attached body. As a result, a decrease in the adhesion between the adhesive layer and the adherend can be suppressed. In order to sufficiently suppress the curing shrinkage of the cured product layer (adhesive layer), the content of the acrylic oligomer (A) is preferably 20 parts by weight or less and more preferably 15 parts by weight with respect to 100 parts by weight of the total amount of the curable component. Below. If the content of the acrylic oligomer (A) in the adhesive is too large, the reaction rate when the active energy ray is irradiated to the adhesive is drastically reduced, and it may constitute a curing failure. another On the one hand, the acrylic oligomer (A) is preferably contained in an amount of 3 parts by weight or more relative to 100 parts by weight of the total amount of the hardenable component, more preferably 5 parts by weight or more.

When considering the workability or uniformity of coating, the active energy ray The hardening adhesive is preferably of low viscosity. Therefore, the acrylic oligomer (A) composed of polymerized (meth)acrylic monomers is also preferably of low viscosity. The acrylic oligomer which belongs to low viscosity and can prevent hardening and shrinkage of the adhesive layer preferably has a weight average molecular weight (Mw) of 15,000 or less, and more preferably 10,000 or less, and particularly preferably 5000 or less. On the other hand, in order to sufficiently suppress the curing shrinkage of the cured product layer (adhesive layer), the weight average molecular weight (Mw) of the acrylic oligomer (A) is preferably 500 or more, and more preferably 1000 or more, and particularly preferably It is more than 1500. Specifically, for example, examples of the (meth)acrylic monomer constituting the acrylic oligomer (A) include: methyl (meth)acrylate, ethyl (meth)acrylate, n-propylene (Meth)acrylate, isopropyl (meth)acrylate, 2-methyl-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-dimethylbutyl (meth)acrylate, n-hexyl (meth)acrylate, hexadecyl (meth)acrylate, n- Octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-2-propylpentyl (meth)acrylate, N-octadecyl (meth)acrylate (Meth)acrylic acid (C 1-20) alkyl esters, and, for example, cycloalkyl (meth) acrylates (such as cyclohexyl (meth) acrylate, cyclopentyl (meth Group) acrylate, etc.), aralkyl (meth)acrylate (such as benzyl (meth)acrylate, etc.), polycyclic (meth)acrylate (such as 2-isobornyl (meth)acrylic acid Ester, 2-nor camphenyl methyl (meth) acrylate, 5-nor camphen-2-yl-methyl (meth) acrylate, 3-methyl-2-nor camphenyl methyl (meth ) Acrylates, etc.), (meth)acrylates containing hydroxyl groups (eg hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2,3-dihydroxypropylmethyl -Butyl(meth)methacrylate, etc.), (meth)acrylates containing alkoxy or phenoxy groups (2-methoxyethyl(meth)acrylate, 2-ethoxy Ethyl (meth)acrylate, 2-methoxymethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylic acid Esters, phenoxyethyl (meth)acrylates, etc.), epoxy-containing (meth)acrylates (such as epoxypropyl (meth)acrylates, etc.), halogen-containing (meth) Acrylic esters (e.g. 2,2,2-trifluoroethyl (meth)acrylate, 2,2,2-trifluoroethyl ethyl (meth)acrylate, tetrafluoropropyl (meth)acrylic acid Ester, hexafluoropropyl (meth)acrylate, octafluoropentyl (meth)acrylate, heptafluorodecyl (meth)acrylate, etc.), alkylaminoalkyl (meth)acrylate (For example, dimethylaminoethyl (meth)acrylate, etc.) and the like. These (meth)acrylates can be used alone or in combination of two or more. Specific examples of the acrylic oligomer (A) include: "ARUFON" manufactured by Toya Synthetic Corporation, "ACTFLOW" manufactured by Kken Chemical Co., Ltd., and "JONCRYL" manufactured by BASF Corporation of Japan. Among acrylic oligomers (A) composed of polymerized (meth)acrylic monomers, those with a high logPow value are also preferred. The acrylic oligomer (A) is included in the calculation of the logPow value of the hardening adhesive for polarizing film. In the calculation of the logPow value, the molar number of the component of the acrylic oligomer (A) is the molar number of the (meth)acrylic monomer that has been converted into the acrylic oligomer (A). The acrylic oligomer (A) composed of polymerized (meth)acrylic monomers The logPow value should be 2 or more, more preferably 3 or more, and most preferably 4 or more.

<Photoacid generator (B)>

The aforementioned active energy ray-curable adhesive may contain a photoacid generator (B). When the active energy ray-curable adhesive contains a photoacid generator, the water resistance and durability of the adhesive layer can be improved dramatically compared to when no photoacid generator is included. The photoacid generator (B) can be represented by the following general formula (3).

[Chemical Formula 3] L in general formula (3) ⁺ X ^-

(However, L ⁺ represents a cation and any of, X ^-. Selected from the group consisting represents _{^{PF6 6 -, SbF 6 -,}} AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, disulfide Carbamate anions, relative anions in the SCN-group.)

Suitable onium cations constituting the onium cation L ⁺ of the general formula (3) include, for example, the onium cations selected from the following general formula (4) to general formula (12).

General formula (4)

General formula (5) [Chemical formula 5]

General formula (6)

General formula (7)

General formula (8)

General formula (9) [Chemical formula 9]

General formula (10)

General formula (11)

General formula (12)

(However, in the aforementioned general formulas (4)-(12), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substitution Or unsubstituted aryl, substituted or unsubstituted heterocyclic group, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted heterocyclic oxy, substituted or unsubstituted acryl Group, substituted or unsubstituted carbonyloxy group, substituted or unsubstituted oxycarbonyl group or halogen atom group. R ⁴ represents the same group as disclosed by R ¹ , R ² and R ^3. R ⁵ represents substituted or unsubstituted Substituted alkyl, substituted or unsubstituted alkylthio. R ⁶ and R ⁷ independently represent substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy. R represents halogen atom, hydroxyl, carboxyl, mercapto , Cyano, nitro, substituted or unsubstituted amine formyl, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclic, Substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted heterocyclic oxy, substituted or unsubstituted alkylthio, substituted or unsubstituted arylthio, substituted or unsubstituted Any one of heterocyclic thio group, substituted or unsubstituted acetyl group, substituted or unsubstituted carbonyloxy group, substituted or unsubstituted oxycarbonyl group. Ar ⁴ and Ar ⁵ represent substituted or unsubstituted aryl group, Either a substituted or unsubstituted heterocyclic group. X represents an oxygen or sulfur atom. i represents an integer from 0 to 5. j represents an integer from 0 to 4. k represents an integer from 0 to 3. In addition, adjacent R Each other, Ar ⁴ and Ar ⁵ , R ² and R ³ , R ² and R ⁴ , R ³ and R ⁴ , R ¹ and R ² , R ¹ and R ³ , R ¹ and R ⁴ , R ¹ and R or R ¹ and R ⁵ may also be a ring structure bonded to each other.)

Equivalent to the onium cation (cerium cation) of general formula (4): examples include: dimethylphenyl cerium, dimethyl (o-fluorophenyl) cerium, dimethyl (m-chlorophenyl) cerium, Dimethyl (p-bromophenyl) alkene, dimethyl (p-cyanophenyl) agar, dimethyl (m-nitrophenyl) agar, dimethyl (2,4,6-tribromo Phenyl) cerium, dimethyl (pentafluorophenyl) cerium, dimethyl (p-(trifluoromethyl) phenyl) cerium, dimethyl (P-hydroxyphenyl)ammonium, dimethyl (p-mercaptophenyl)ammonium, dimethyl (p-methylsulfinylphenyl)ammonium, dimethyl (p-methylsulfonylphenyl) ) 鋶, dimethyl (o-ethoxyphenyl) 鋶, dimethyl (o-benzoylphenyl) 鋶, dimethyl (p-methylphenyl) 鋶, dimethyl (p -Isopropylphenyl) agar, dimethyl (p-octadecylphenyl) agar, dimethyl (p-cyclohexylphenyl) agar, dimethyl (p-methoxyphenyl) agar, Dimethyl (o-methoxycarbonylphenyl) amide, dimethyl (p-phenylsulfonylphenyl) amide, (7-methoxy-2-oxo-2H-chromen-4-yl ) Dimethyl alkane, (4-methoxynaphthalene-1-yl) dimethyl alkane, dimethyl (p-isopropoxycarbonylphenyl) agar, dimethyl (2-naphthyl) agar, di Methyl (9-anthracenyl) alkane, diethylphenyl alkane, methyl ethyl phenyl alkane, methyl diphenyl alkane, triphenyl alkane, diisopropylphenyl alkane, diphenyl (4 -Phenylsulfonyl-phenyl)-ammonium, 4,4'-bis(diphenylammonium) diphenyl sulfide, 4,4'-bis[di[(4-(2-hydroxy-ethoxy Yl)-phenyl)] 鋶]] diphenyl sulfide, 4,4'-bis (diphenyl carbamide) biphenylene, diphenyl (o-fluorophenyl) carbamide, diphenyl (m- Chlorophenyl) alkene, diphenyl (p-bromophenyl) agar, diphenyl (p-cyanophenyl) agar, diphenyl (m-nitrophenyl) agar, diphenyl (2, 4,6-tribromophenyl) agaric, diphenyl (pentafluorophenyl) agaric, diphenyl (p-(trifluoromethyl)phenyl) agaric, diphenyl (p-hydroxyphenyl) agaric , Diphenyl (p-mercaptophenyl) alkene, diphenyl (p-methylsulfinylphenyl) alkene, diphenyl (p-methylsulfonylphenyl) alkane, diphenyl (o- Acetylphenyl) amide, diphenyl (o-benzylphenyl) amide, diphenyl (p-methylphenyl) amide, diphenyl (p-isopropylphenyl) amide, Diphenyl (p-octadecylphenyl) alkene, diphenyl (p-cyclohexylphenyl) alkane, diphenyl (p-methoxyphenyl) alkane, diphenyl (o-methoxycarbonyl) Phenyl) alkene, diphenyl (p-phenylsulfonylphenyl) alkene, (7-methoxy-2-oxo-2H-chromen-4-yl) diphenyl alkane, (4- Methoxynaphthalene-1-yl) diphenyl alkene, diphenyl (p-isopropoxycarbonylphenyl) alkene, diphenyl (2-naphthyl) alkane, diphenyl (9-anthracenyl) agar, ethyl diphenyl agar, methyl ethyl (o-tolyl) agar, methyl di (p-tolyl) agar, tri (p-tolyl) agar, diisopropyl (4-phenylsulfonylphenyl) alkane, diphenyl (2-thienyl) alkane, diphenyl (2-furyl) alkane, diphenyl (9-ethyl-9Hcarbazole-3 -Base) Kaku, etc. However, it is not limited to these.

Equivalent to the onium cation of the general formula (5) (oxide cation): Examples include: dimethylphenyl oxide oxide, dimethyl (o-fluorophenyl) oxide oxide, dimethyl (m-chlorophenyl) oxide oxide, dimethyl (p-bromophenyl) oxide oxide , Dimethyl (p-cyanophenyl) oxide, dimethyl (m-nitrophenyl) oxide, dimethyl (2,4,6-tribromophenyl) oxide, dimethyl (Pentafluorophenyl) alkoxide, dimethyl (p-(trifluoromethyl)phenyl) alkoxide, dimethyl (p-hydroxyphenyl) alkoxide, dimethyl (p-mercaptophenyl) Oxygen oxide, dimethyl (p-methylsulfinylphenyl) oxymethylene, dimethyl (p-methylsulfonylphenyl) oxymethylene, dimethyl (o-ethoxyphenyl) oxymethylene , Dimethyl (o-benzylphenyl) oxide, dimethyl (p-methylphenyl) oxide, dimethyl (p-isopropylphenyl) oxide, dimethyl ( p-octadecylphenyl) alkoxide, dimethyl (p-cyclohexylphenyl) alkoxide, dimethyl (p-methoxyphenyl) alkoxide, dimethyl (o-methoxycarbonylbenzene Group) oxidized cerium oxide, dimethyl (p-phenylsulfonylphenyl) oxidized cerium oxide, (7-methoxy-2-oxo-2H-chromen-4-yl) dimethyl oxidized cerium oxide, ( 4-Methoxynaphthalene-1-yl) dimethyl alkoxide, dimethyl (p-isopropoxycarbonylphenyl) alkoxide, dimethyl (2-naphthyl) alkoxide, dimethyl (9 -Anthracenyl) oxide, diethylphenyl oxide, methylethylphenyl oxide, methyldiphenyl oxide, triphenyl oxide, diisopropylphenyl oxide, diphenyl oxide (4-Phenylsulfonyl-phenyl)-oxane, 4,4'-bis(diphenyloxane)diphenyl sulfide, 4,4'-bis[di[(4-(2- Hydroxy-ethoxy)-phenyl)] oxybenzone]diphenyl sulfide, 4,4'-bis(diphenyloxy Carbamazepine) biphenylene, diphenyl (o-fluorophenyl) oxide, diphenyl (m-chlorophenyl) oxide, diphenyl (p-bromophenyl) oxide, diphenyl ( p-cyanophenyl) oxide, diphenyl (m-nitrophenyl) oxide, diphenyl (2,4,6-tribromophenyl) oxide, diphenyl (pentafluorophenyl) )Cerbium oxide, diphenyl (p-(trifluoromethyl)phenyl) cerium oxide, diphenyl (p-hydroxyphenyl) cerium oxide, diphenyl (p-mercaptophenyl) cerium oxide, diphenyl (P-methylsulfinylphenyl) oxide, diphenyl (p-methylsulfonylphenyl) oxide, diphenyl (o-ethoxyphenyl) oxide, diphenyl ( o-benzylphenylphenyl) oxide, diphenyl (p-methylphenyl) oxide, diphenyl (p-isopropylphenyl) oxide, diphenyl (p-octadecyl Phenyl) alkoxide, diphenyl (p-cyclohexylphenyl) alkoxide, diphenyl (p-methoxyphenyl) alkoxide, diphenyl (o-methoxycarbonylphenyl) alkoxide, Diphenyl (p-phenylsulfonylphenyl) oxide, (7-methoxy-2-oxo-2H-chromen-4-yl) diphenyl oxide, (4-methoxy Naphthalene-1-yl)diphenyl oxide, diphenyl (p-isopropoxycarbonylphenyl) oxide, diphenyl (2-naphthyl) oxide, diphenyl (9-anthryl) oxidation Cerium oxide, ethyl diphenyl cerium oxide, methyl ethyl (o-tolyl) cerium oxide, methyl bis (p-tolyl) cerium oxide, tri (p-tolyl) cerium oxide, diisopropyl ( 4-Phenylsulfonylphenyl) oxide, diphenyl (2-thienyl) oxide, diphenyl (2-furyl) oxide, diphenyl (9-ethyl-9Hcarbazole- 3-yl) oxirane etc., however, it is not limited to these.

Equivalent to the onium cation (phosphonium cation) of the general formula (6): Examples of phosphonium cations: for example: trimethylphenylphosphonium, triethylphenylphosphonium, tetraphenylphosphonium, triphenyl (p-fluoro Phenyl)phosphonium, triphenyl(o-chlorophenyl)phosphonium, triphenyl(m-bromophenyl)phosphonium, triphenyl(p-cyanophenyl)phosphonium, triphenyl(m-nitro Phenyl)phosphonium, three Phenyl (p-phenylsulfonylphenyl) phosphonium, (7-methoxy-2-oxo-2H-chromen-4-yl) triphenylphosphonium, triphenyl (o-hydroxyphenyl ) Phosphonium, triphenyl (o-acetyl phenyl) phosphonium, triphenyl (m-benzyl phenyl) phosphonium, triphenyl (p-methylphenyl) phosphonium, triphenyl (p -Isopropoxyphenyl)phosphonium, triphenyl(o-methoxycarbonylphenyl)phosphonium, triphenyl(1-naphthyl)phosphonium, triphenyl(9-anthryl)phosphonium, triphenyl( 2-thienyl)phosphonium, triphenyl(2-furyl)phosphonium, triphenyl(9-ethyl-9Hcarbazol-3-yl)phosphonium, etc., however, it is not limited to these.

Equivalent to the onium cation of the general formula (7) (pyridinium cation): Examples of pyridinium cations: N-phenylpyridinium, N-(o-chlorophenyl)pyridinium, N-(m- Chlorophenyl)pyridinium, N-(p-cyanophenyl)pyridinium, N-(o-nitrophenyl)pyridinium, N-(p-acetylphenyl)pyridinium, N-( p-isopropylphenyl)pyridinium, N-(p-octadecyloxyphenyl)pyridinium, N-(p-methoxycarbonylphenyl)pyridinium, N-(9-anthryl)pyridine Onium, 2-chloro-1-phenylpyridinium, 2-cyano-1-phenylpyridinium, 2-methyl-1-phenylpyridinium, 2-vinyl-1-phenylpyridinium, 2 -Phenyl-1-phenylpyridinium, 1,2-diphenylpyridinium, 2-methoxy-1-phenylpyridinium, 2-phenoxy-1-phenylpyridinium, 2-ethyl Acyl-1-(p-tolyl)pyridinium, 2-methoxycarbonyl-1-(p-tolyl)pyridinium, 3-fluoro-1-naphthylpyridinium, 4-methyl-1-( 2-furyl)pyridinium, N-methylpyridinium, N-ethylpyridinium, etc., however, it is not limited to these.

Equivalent to the onium cation of the general formula (8) (quinolinium cation): Examples of quinolinium cations: N-methylquinolinium, N-ethylquinolinium, N-phenylquinoline Onium, N-naphthylquinolinium, N-(o-chlorophenyl) quinolinium, N-(m-chlorophenyl) Quinolinium, N-(p-cyanophenyl)quinolinium, N-(o-nitrophenyl)quinolinium, N-(p-acetylphenyl)quinolinium, N-( p-isopropylphenyl) quinolinium, N-(p-octadecyloxyphenyl) quinolinium, N-(p-methoxycarbonylphenyl) quinolinium, N-(9-anthracene Group) quinolinium, 2-chloro-1-phenylquinolinium, 2-cyano-1-phenylquinolinium, 2-methyl-1-phenylquinolinium, 2-vinyl-1 -Phenylquinolinium, 2-phenyl-1-phenylquinolinium, 1,2-diphenylquinolinium, 2-methoxy-1-phenylquinolinium, 2-phenoxy -1-phenylquinolinium, 2-acetoxy-1-phenylquinolinium, 2-methoxycarbonyl-1-phenylquinolinium, 3-fluoro-1-phenylquinolinium, 4 -Methyl-1-phenylquinolinium, 2-methoxy-1-(p-tolyl)quinolinium, 2-phenoxy-1-(2-furyl)quinolinium, 2- Acetyl-1-(2-thienyl)quinolinium, 2-methoxycarbonyl-1-methylquinolinium, 3-fluoro-1-ethylquinolinium, 4-methyl-1-iso Propylquinolinium and the like, however, are not limited to these.

Equivalent to the onium cation of the general formula (9) (isoquinolinium cation): Examples of the isoquinolinium cation: N-phenylisoquinolinium, N-methylisoquinolinium, N- Ethyl isoquinolinium, N-(o-chlorophenyl) isoquinolinium, N-(m-chlorophenyl) isoquinolinium, N-(p-cyanophenyl) isoquinolinium, N-(o-nitrophenyl) isoquinolinium, N-(p-acetylphenyl) isoquinolinium, N-(p-isopropylphenyl) isoquinolinium, N-( p-octadecyloxyphenyl) isoquinolinium, N-(p-methoxycarbonylphenyl) isoquinolinium, N-(9-anthryl) isoquinolinium, 1,2-diphenyl Isoquinolinium, N-(2-furyl)isoquinolinium, N-(2-thienyl)isoquinolinium, N-naphthylisoquinolinium, etc., however, it is not limited to these.

Equivalent to the onium cation of general formula (10) (benzoxazolium cation, benzothiazolium cation): Examples of benzoxazolium cations: N-methylbenzoxazolium, N-ethylbenzoxazolium, N-naphthylbenzoxazolium, N-phenylbenzoxazolium Oxazolium, N-(p-fluorophenyl)benzoxazolium, N-(p-chlorophenyl)benzoxazolium, N-(p-cyanophenyl)benzoxazolium, N -(o-methoxycarbonylphenyl)benzoxazolium, N-(2-furyl)benzoxazolium, N-(o-fluorophenyl)benzoxazolium, N-(p- Cyanophenyl)benzoxazolium, N-(m-nitrophenyl)benzoxazolium, N-(p-isopropoxycarbonylphenyl)benzoxazolium, N-(2- Thienyl)benzoxazolium, N-(m-carboxyphenyl)benzoxazolium, 2-mercapto-3-phenylbenzoxazolium, 2-methyl-3-phenylbenzoxazol Oxazolium, 2-methylthio-3-(4-phenylsulfonylphenyl)benzoxazolium, 6-hydroxy-3-(p-tolyl)benzoxazolium, 7-mercapto- 3-phenylbenzoxazolium, 4,5-difluoro-3-ethylbenzoxazolium, etc., however, it is not limited to these.

Examples of benzothiazolium cations: N-methylbenzothiazolium, N-ethylbenzothiazolium, N-phenylbenzothiazolium, N-(1-naphthyl)benzothiazole Onium, N-(p-fluorophenyl)benzothiazolium, N-(p-chlorophenyl)benzothiazolium, N-(p-cyanophenyl)benzothiazolium, N-(o- Methoxycarbonylphenyl)benzothiazolium, N-(p-tolyl)benzothiazolium, N-(o-fluorophenyl)benzothiazolium, N-(m-nitrophenyl)benzo Thiazolium, N-(p-isopropoxycarbonylphenyl) benzothiazolium, N-(2-furyl)benzothiazolium, N-(4-methylthiophenyl) benzothiazolium, N -(4-phenylsulfonylphenyl)benzothiazolium, N-(2-naphthyl)benzothiazolium, N-(m-carboxyphenyl)benzothiazolium, 2-mercapto-3- Phenylbenzothiazolium, 2-methyl-3-phenylbenzothiazolium, 2-methylthio-3-phenylbenzothiazolium, 6-hydroxy-3-phenylbenzothiazolium, 7 -Mercapto-3-phenylbenzothiazolium, 4,5-difluoro-3- Phenylbenzothiazolium and the like, however, are not limited to these.

Equivalent to the onium cation of the general formula (11) (furanyl or thienylphosphonium cation): examples include difuranylphosphonium, dithienylphosphonium, and bis(4,5-dimethyl-2-furan Group) phosphonium, bis(5-chloro-2-thienyl) sulfonium, bis(5-cyano-2-furanyl) sulfonium, bis(5-nitro-2-thienyl) sulfonium, bis (5-Acetyl-2-furanyl) sulfonium, bis(5-carboxy-2-thienyl) sulfonium, bis(5-methoxycarbonyl-2-furanyl) sulfonium, bis(5-benzene Yl-2-furyl)phosphonium, bis(5-(p-methoxyphenyl)-2-thienyl)phosphonium, bis(5-vinyl-2-furyl)phosphonium, bis(5 -Ethynyl-2-thienyl) sulfonium, bis(5-cyclohexyl-2-furyl) sulfonium, bis(5-hydroxy-2-thienyl) sulfonium, bis(5-phenoxy-2 -Furanyl) sulfonium, bis(5-mercapto-2-thienyl) sulfonium, bis(5-butylthio-2-thienyl) sulfonium, bis(5-phenylthio-2-thienyl) Phonium, etc., however, are not limited to these.

Equivalent to the onium cation of the general formula (12) (diarylionium cation): examples include: diphenyl sulfonium, bis(p-tolyl) sulfonium, bis(p-octylphenyl) sulfonium , Bis(p-octadecylphenyl) sulfonium, bis(p-octyloxyphenyl) sulfonium, bis(p-octadecyloxyphenyl) sulfonium, phenyl (p-octadecane Oxyphenyl) konium, 4-isopropyl-4'-methyldiphenyl konium, (4-isobutylphenyl)-p-tolyl konium, bis(1-naphthyl) konium Onium, bis(4-phenylsulfonylphenyl) sulfonium, phenyl (6-benzyl-9-ethyl-9H-carbazol-3-yl) sulfonium, (7-methoxy -2-oxo-2H-chromen-3-yl)-4'-isopropylphenylphosphonium, etc., however, it is not limited to these.

Next, the relative anion X ^- in the general formula (3) will be explained.

The relative anion X ^- in the general formula (3) is not particularly limited in principle, however, it is preferably a non-nucleophilic anion. When the relative anion X ^{-is a} non-nucleophilic anion, since it is not easy to cause nucleophilic reactions in the cations coexisting in the molecule or various materials used in combination, the result can be improved by the photoacid generation indicated by the general formula (2) The stability over time of the agent itself or its adhesive. The non-nucleophilic anions referred to herein refer to anions with low ability to cause nucleophilic reactions. Such anions include such _{^{as: PF 6 -, SbF 6 -}} , AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, urethane disulfide anion, SCN ^- and the like.

In the illustrated embodiment of the anion, particularly suitable as a general formula opposing anions (3) X ^- as exemplified by: PF ₆ ^-, SbF ₆ ^- and AsF ₆ ^-, particularly preferably include such as: PF ₆ ^-, SbF ₆ ^-.

Therefore, a specific example of an ideal onium salt constituting the photoacid generator (B) is an onium salt composed of the following, namely: the onium cation represented by the general formula (3) to the general formula (12) exemplified above specific examples of the structures selected from _{^{PF 6 -, SbF 6 -,}} AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, urethane disulfide anion, SCN ^- anion of.

Specifically, examples of ideal specific examples of the photoacid generator (B) include: "CYRACURE UVI-6992" and "CYRACURE UVI-6974" (above are manufactured by Japan Dow Chemical Co., Ltd.) , ``ADEKA OPTOMER SP150'', ``ADEKA OPTOMER SP152'', ``ADEKA OPTOMER SP170'', ``ADEKA OPTOMER SP172'' (above manufactured by ADEKA Co., Ltd.), ``IRGACURE250'' (Ciba Specialty Chemicals) Company), ``CI-5102'', ``CI-2855'' (the above is manufactured by Soda Japan), ``SAN-AID SI-60L'', ``SAN-AID SI-80L'', ``SAN-AID SI-100L'' , "SAN-AID SI-110L", "SAN-AID SI-180L" (above manufactured by Sanxin Chemical Co., Ltd.), "CPI-100P", "CPI-100A" (above are SAN-APRO) shares Co., Ltd.), ``WPI-069'', ``WPI-113'', ``WPI-116'', ``WPI-041'', ``WPI-044'', ``WPI-054'', ``WPI-055'', ``WPAG- "281", "WPAG-567", "WPAG-596" (above manufactured by Wako Pure Chemical Industries, Ltd.).

The content of the photoacid generator (B) is less than 10 parts by weight relative to the total amount of the hardening component of 100 parts by weight, and is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, and particularly preferably 0.1 to 3 parts by weight.

<Compound (C) containing any of alkoxy group and epoxy group>

The active energy ray-curable adhesive described above may contain a compound (C) containing any one of an alkoxy group and an epoxy group. For example, in the relationship with the hydroxyl group of the PVA polarizer, the compound (C1) containing an alkoxy group will undergo a condensation reaction of an alkoxy group and a hydroxyl group, and the compound (C2) containing an epoxy group will undergo an epoxy group Addition reaction with hydroxyl groups, and can give the active energy ray hardening adhesive more firm adhesion. When using an epoxy group-containing compound (C2), by the addition reaction of an epoxy group and a hydroxyl group, a secondary hydroxyl group is formed after the reaction, and the overall water absorption rate of the present invention may be increased. Therefore, it is more suitable to use Alkoxy compound (C1). That is, through the active energy ray-curable adhesive containing the photoacid generator (B) and the compound having an alkoxy group (C1), the polarizer and the transparent protective film are laminated, and under the irradiation of the active energy ray, by generating Acids from photoacid generators (B), compounds with alkoxy groups (C1) The alkoxy group and the hydroxyl group of the polarizer will undergo a condensation reaction, and show good adhesion between the polarizer and the transparent protective film. In addition, by the condensation reaction of the compounds (C1) having alkoxy groups, an adhesive layer with a lower water absorption rate is formed, and the optical durability in a severe environment under high temperature and high humidity can be satisfied.

The aforementioned active energy ray-curable adhesive contains alkoxy The compound (C) of any one of the group and the epoxy group may be used alone or in combination. Moreover, the compound (C) containing either an alkoxy group or an epoxy group can also be used together with the compound (C1) containing an alkoxy group and the compound (C2) containing an epoxy group. In addition, the compound (C) containing any of the alkoxy group and the epoxy group may be used with or without the photoacid generator (B). However, if the hydroxyl and alkoxy groups of the PVA polarizer are promoted From the viewpoint of the reaction of epoxy groups, the compound (C) containing any of alkoxy groups and epoxy groups is preferably used in combination with the photoacid generator (B).

(Compound with alkoxy group (C1))

The compound (C1) 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 known ones can be used. For example, it can be exemplified by the following general formula: -(CH ₂ ) _n -OR (where n is an integer of 1 to 3, and R represents an alkyl group of 1 to 4 carbon or H. In the foregoing formula R is preferably a methyl group.) The compound represented by an alkoxy group as a substituent. Specifically, for example, an alkoxy-containing radical polymerizable compound such as alkoxyalkyl (meth)acrylate, alkoxyalkyl (meth)acrylamide, hydroxymethyl Based melamine, alkoxymethylated melamine and other melamine compounds, amine-based resin and silane coupling agent. Specific examples of the radical polymerizable compound containing an alkoxy group include: WASMER 2MA, WASMER 3MA, WASMER IBM, N-isobutoxymethacrylamide, WASMER EMA, N-MAM manufactured by Kasano Kosei Corporation -PC, MM90, WASMER A, etc. Specific examples of melamine compounds can be exemplified: M-3, MK, M-6, M-100, MC, etc. of SUMITEX RESIN series manufactured by Sumitomo Chemical Co., Ltd. or NIKALAC MW-30, MW-100LM manufactured by Sanwa Chemical Co., Ltd. , MX-750LM, MX-280, MX-270, etc. Among these, from the viewpoint of reactivity, WASMER 2MA, N-MAM-PC, MX-750LM, etc. are preferably used. In addition, when calculating the glass transition temperature Tg of the adhesive layer, the compound having an alkoxy group and the polymer (C1) were not included in the calculation.

(Compound with epoxy group (C2))

As the compound (C2) having an epoxy group, a compound having more than one epoxy group in the molecule or a polymer (epoxy resin) having more than two epoxy groups in the molecule can be used. When a polymer (epoxy resin) is used, a compound having two or more functional groups having reactivity with epoxy groups in the molecule may be used in combination. Here, for example, the functional group having reactivity with an epoxy group may include a carboxyl group, a phenolic hydroxyl group, a mercapto group, a primary or secondary aromatic amine group, and the like. Considering the three-dimensional hardenability, these functional groups are particularly preferably those having two or more in one molecule.

For example, polymers with more than one epoxy group in the molecule can be exemplified by epoxy resins, and include: bisphenol A epoxy resins derived from bisphenol A and epichlorohydrin, derived from bisphenol Bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F phenolic Epoxy resin, alicyclic epoxy resin, diphenyl ether epoxy resin, hydroquinone epoxy resin, naphthalene epoxy resin, biphenyl epoxy resin, fuze epoxy resin, trifunctional epoxy resin Multifunctional epoxy resin such as epoxy resin or tetrafunctional epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, allantoin epoxy resin, triisocyanate epoxy resin, Aliphatic chain epoxy resin, etc., and these epoxy resins can also be halogenated or hydrogenated. For example, commercially available epoxy resin products include: JER coatings 828, 1001, 801N, 806, 807, 152, 604, 630, 871, YX8000, YX8034, YX4000, manufactured by Japan Epoxy Resin Co., Ltd. EPICLON830, EXA835LV, HP4032D, HP820 manufactured by DIC Co., Ltd., EP4100 series, EP4000 series, EPU series, and DAICEL Chemical Co., Ltd.-made CELLOXIDE series (2021, 2021P, 2083) , 2085, 3000, etc.), EPOLEAD series, EHPE series, YD series, YDF series, YDCN series, YDB series, phenoxy resin (polyhydroxyl synthesized from bisphenols and epichlorohydrin) Polyether with epoxy groups at both ends; YP series, etc.), DENACOL series manufactured by Nagase Chemtex, EPOLIGHT series manufactured by Kyoeisha Chemical Co., etc. However, it is not limited to these. Two or more of these epoxy resins may be used in combination. In addition, when calculating the glass transition temperature Tg of the adhesive layer, the compound (C2) having an epoxy group was not included in the calculation.

Contains 100 parts by weight of the total amount of hardenable components, including alkoxy The compounding amount of the compound (C) of any one of the group and the epoxy group is usually 30 parts by weight or less, if the content of the compound (C) in the active energy ray-curable adhesive is If the amount is too large, the adhesiveness will decrease, and the impact resistance to the drop test may deteriorate. The content of the aforementioned compound (C) in the active energy ray-curable adhesive is more preferably 20 parts by weight or less. On the other hand, from the viewpoint of water resistance, the active energy ray-curable adhesive preferably contains 2 parts by weight or more of the compound (C), more preferably 5 parts by weight or more.

<isocyanate compound (D)>

The active energy ray-curable adhesive of the present invention may contain an isocyanate compound (D). The isocyanate compound (D) is a compound having at least one isocyanate group in the molecule. When the active energy ray-curable adhesive contains an isocyanate compound (D), the hydroxyl group on the surface of the polarizer interacts with the isocyanate group, thereby giving the polarizing film stronger adhesion and water resistance. In addition, when the active energy ray-curable adhesive contains an N-hydroxyalkyl group-containing (meth)acrylamide derivative as a radical polymerizable compound, if the N-hydroxyalkyl group-containing (meth)acrylamide As the content of the amine derivative increases, the hydroxyl group is contained in the adhesive layer, so the overall water absorption tends to increase, and as a result, the optical durability under severe humidified environments tends to decrease. By combining the (meth)acrylamide derivative containing N-hydroxyalkyl and the compound having an isocyanate group, it is not helpful to form a carbamate bond with the hydroxyl group and the isocyanate group of the polarizer, and It can maintain the adhesion while reducing the overall water absorption rate.

Examples of the isocyanate compound (D) include: polyfunctional isocyanate Compounds, active energy ray-curable isocyanate compounds, etc. For example, the multifunctional isocyanate compound can be exemplified by: 1,2-ethylidene diisocyanate, 1,4-butylene diisocyanate, 1,6-hexamethylene diisocyanate, etc. Aliphatic polyisocyanates; cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated methylenediphenyl diisocyanate, hydrogenated xylene diisocyanate and other alicyclic polyisocyanates; 2, Aromatic polyisocyanates such as 4-toluene diisocyanate, 2,6-tolyl diisocyanate, 4,4'-diphenylmethane diisocyanate, and stubble diisocyanate. For example, the aforementioned isocyanate compound (D) can also be exemplified by: trimethylolpropane/toluene diisocyanate adduct [manufactured by Japan Polyurethane Industry Co., Ltd., trade name "CORONATE L" ], trimethylolpropane/hexamethylene diisocyanate adduct [manufactured by Japan Polyurethane Industry Co., Ltd., trade name "CORONATE HL"], trade name "CORONATE HX" (Japanese polyamine group Formate Industrial Co., Ltd.), trimethylolpropane/stubble diisocyanate adduct [Mitsui Chemical Co., Ltd., trade name "TAKENATE110N"] and other commercially available products. Examples of the active energy ray-curable isocyanate compound (D) include isocyanates having a (meth)acryloyl group. For example, KARENZ AOI (manufactured by Showa Denko Co., Ltd.), KARENZ BEI (Showa Denko) Co., Ltd.), Laromer LR9000 (manufactured by BASF) and other commercially available products.

Relative to 100 parts by weight of the total amount of the hardenable component, isocyanate The compounding amount of the compound (D) is usually 30 parts by weight or less. If the content of the aforementioned compound (D) in the active energy ray-curable adhesive is too large, the adhesion will be lowered and it will have impact resistance to the drop test. Worsening situation. The content of the aforementioned compound (D) in the active energy ray-curable adhesive is more preferably 20 parts by weight or less. On the other hand, from the viewpoint of water resistance, the active energy ray-curable adhesive preferably contains 0.1 parts by weight or more of the compound (D), more It should preferably contain more than 1 part by weight.

<Silane Coupling Agent (E)>

When the curing adhesive for polarizing film of the present invention is an active energy ray-curable curing type, the silane coupling agent (E) is preferably an active energy ray-curable compound. However, even if it is not active energy ray-curable, the same Water resistance.

As a specific example of the silane coupling agent (E), active energy ray hardening Examples of the sexual compounds are: vinyl trichlorosilane, vinyl trimethoxy silane, vinyl triethoxy silane, 2-(3,4 epoxycyclohexyl) ethyl trimethoxy silane, 3-epoxypropyl Oxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane , 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxy Silane, 3-methacryloxypropyltriethoxysilane, 3-propenyloxypropyltrimethoxysilane, etc.

More preferably, 3-methacryloxypropyltrimethoxysilane and 3-propenyloxypropyltrimethoxysilane.

A specific example of the silane coupling agent that is not active energy ray-curable is preferably a silane coupling agent (E1) having an amine group. Specific examples of the silane coupling agent (E1) having an amine group include: γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-amineethyl Group) aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl Group) aminopropylmethyl diethoxysilane, γ-(2-aminoethyl)aminopropyltriisopropoxysilane, γ-(2-(2-aminoethyl)aminoethyl)aminopropyl Trimethoxysilane, γ-(6-aminohexyl)aminopropyltrimethoxysilane, 3-(N-ethylamino)-2-methylpropyltrimethoxysilane, γ-ureapropyltrimethoxysilane Silane, γ-ureapropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl -γ-aminopropyltriethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-cyclohexylaminomethyl diethoxymethylsilane, N-phenylaminomethyl Amino group-containing silanes such as trimethoxysilane, (2-aminoethyl)aminemethyltrimethoxysilane, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine; N-(1,3-dimethylbutylene)-3-(triethoxysilyl)-1-propanamine and other ketimine type silanes.

Only one type of silane coupling agent (E1) with an amine group may be used, and You can also use a combination of multiple species. Among these, in order to ensure good adhesion, γ-aminopropyltrimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl) Aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropylmethyldiethoxysilane, N -(1,3-dimethylbutylene)-3-(triethoxysilyl)-1-propanamine.

Silane coupling relative to 100 parts by weight of total hardenable component The blending amount of the agent (E) is preferably in the range of 0.01 to 20 parts by weight, and is preferably 0.05 to 15 parts by weight, more preferably 0.1 to 10 parts by weight. This is because when the blending amount is more than 20 parts by weight, the storage stability of the adhesive deteriorates, and when it is less than 0.1 parts by weight, the effect of water resistance adhesion cannot be sufficiently exhibited. In addition, when calculating the glass transition temperature Tg of the adhesive layer, the silane coupling agent was not used. (E) included in the calculation.

Silane coupling agent other than the aforementioned, which is not active energy ray curable Specific examples include: 3-ureapropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane , Bis(triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, imidazole silane, etc.

For the aforementioned photoacid generator (B), including alkoxy groups and epoxy groups For any of the compound (C), isocyanate compound (D), and silane coupling agent (E), the logPow value of each component should also be 1 or more, and more preferably 2 or more. In addition, the photoacid generator (B) and the silane coupling agent (E) are not included in the calculation of the logPow value of the hardening adhesive for polarizing films. On the other hand, the compound (C) and the isocyanate compound (D) containing any of the alkoxy group and the epoxy group are included in the calculation of the logPow value of the hardening adhesive for polarizing film.

<Additives other than the aforementioned>

In addition, in the hardening type adhesive for polarizing films of the present invention, various additives may be blended as other arbitrary components within a range that does not impair the object and effect of the present invention. Examples of the aforementioned additives include: polyamidoamine, polyamidoamide imine, polyurethane, polybutadiene, polychloroprene, polyether, polyester, styrene-butadiene block copolymerization Polymers, petroleum resins, xylene resins, ketone resins, cellulose resins, fluorine-based oligomers, polysiloxane-based oligomers, polysulfide-based oligomers and other polymers or oligomers; phenothiazine, 2, 6-di-t-butyl-4-cresol and other polymerization inhibitors; polymerization initiation aids; leveling agents; wettability modifiers; surfactants; plasticizers; ultraviolet absorbers; inorganic fillers; pigments; Dyes, etc. Among various additives, the one with the highest logPow value is also suitable. The logPow value of various additives should be 2 or more, more preferably 3 or more, and most preferably 4 or more. In addition, these additives are not included in the calculation of the logPow value of the hardening adhesive for polarizing films.

The aforementioned addition is relative to 100 parts by weight of the total amount of the hardenable component The agent is usually 0 to 10 parts by weight, and preferably 0 to 5 parts by weight, most preferably 0 to 3 parts by weight.

<viscosity of adhesive>

The curable adhesive for polarizing films of the present invention contains the aforementioned curable components. However, from the viewpoint of coatability, the viscosity of the adhesive is preferably 100 cp or less at 25°C. On the other hand, when the hardening adhesive for polarizing film of the present invention is 100 cp at 25° C., the temperature of the adhesive may be controlled to be 100 cp or less during coating. The more ideal range of viscosity is 1~80cp, the most ideal is 10~50cp. Viscosity can be measured using TVE22LT, an E-type viscometer manufactured by Toki Industry Corporation.

In addition, from the viewpoint of safety, the polarized light of the present invention is thin For the film-curing adhesive, a material with low skin irritation is preferably used as the aforementioned curable component. Skin irritation can be judged by the so-called P.I.I index. P.I.I is widely used to show the degree of skin disorders, and is measured by the Choi method. The measured value is expressed in the range of 0 to 8. The smaller the value, the lower the irritation. However, because the error of the measured value is large, it can be grasped as a reference value. P.I.I is preferably 4 or less, and more preferably 3 or less, and most preferably 2 or less.

<polarizing film>

The polarizing film of the present invention has at least one side of the polarizer interposed by the aforementioned polarizer A transparent protective film is bonded to the adhesive layer formed by the hardened layer of the hardening adhesive for the optical film. As described above, the adhesive layer belonging to the hardened material layer has an overall water absorption rate of 10% by weight or less.

<adhesive layer>

The thickness of the adhesive layer formed by the aforementioned hardening adhesive should be controlled to 0.1 to 3 μm. The thickness of the adhesive layer is more preferably 0.3 to 2 μm, and further preferably 0.5 to 1.5 μm. In order to suppress the occurrence of adhesion defects by the cohesive force of the adhesive layer or the appearance defects (bubbles) during lamination, it is preferable to make the thickness of the adhesive layer 0.1 μm or more. On the other hand, if the adhesive layer is thicker than 3 μm, there is a possibility that the polarizing film cannot satisfy the durability.

Moreover, the hardening type adhesive should be selected as the adhesive formed by this The Tg of the layer will constitute above 60°C, and more preferably above 70°C. Furthermore, it is preferably above 75°C, further above 100°C, or even above 120°C. On the other hand, if the Tg of the adhesive layer is too high, the bendability of the polarizing film will decrease. Therefore, the Tg of the adhesive layer should preferably be 300°C or lower, further 240°C or lower, or even 180°C or lower. Tg <glass transition temperature> is measured using the following measuring conditions using a dynamic viscoelasticity measuring device RSAIII made by TA Instruments.

Sample size: width 10mm, length 30mm, fixture distance 20mm, measurement mode: stretching, frequency: 1Hz, heating rate: 5°C/min

The dynamic viscoelasticity is measured and used as the temperature Tg at the peak top of tan δ.

In addition, the hardening type adhesive preferably has a storage modulus of 1.0×10 ⁶ Pa or higher in a field where the storage modulus of the adhesive layer formed by this is 70° C. or lower. Furthermore, it is more preferably 1.0×10 ⁷ Pa or more. The storage modulus of the adhesive layer will affect the polarizer cracking when the polarizing film is subjected to a thermal cycle (-40°C to 80°C, etc.). When the storage modulus is low, the polarizer cracking problem is likely to occur. The temperature range with a high storage modulus is more preferably below 80°C and most preferably below 90°C. The storage modulus was measured with the same measurement conditions using the dynamic viscoelasticity measuring device RSAIII made by TA Instruments at the same time as Tg<glass transition temperature>. The dynamic viscoelasticity is measured and the value of the storage modulus (Eˊ') is used.

The polarizing film of the present invention includes the steps of bonding the polarizing member and the transparent protective film after applying a hardening adhesive on the surface of the polarizing member where the adhesive layer is formed and/or the transparent protective film forming the adhesive layer; The step of curing the hardening adhesive to form an adhesive layer.

The polarizer and the transparent protective film may be surface-modified before applying the hardening adhesive. Specific treatments include, for example, treatment using corona treatment, plasma treatment, and saponification treatment.

The application method of the hardening adhesive can be appropriately selected according to the viscosity of the hardening adhesive or the target thickness. For example, examples of coating methods include: reverse coater, gravure coater (direct, reverse or indirect), rod reverse coater, roll coater, die casting die coating Machine, bar coater, rod coater, etc. In addition, for the coating, a dipping method or the like can be used as appropriate.

The polarizer and the transparent protective film are bonded through the hardening adhesive that has been applied as described above. The bonding of the polarizer and the transparent protective film can be performed by a roll laminator or the like.

<hardening of adhesive>

The hardening type adhesive for polarizing films of the present invention can be used as an active energy ray hardening type adhesive or a thermosetting type adhesive. It can be used in the form of electron beam curing type, ultraviolet curing type, visible light curing type in active energy ray curing type adhesive. From the viewpoint of productivity, the form of the aforementioned hardening adhesive is that the active energy ray curing adhesive is superior to the thermosetting adhesive. Furthermore, from the viewpoint of productivity, the active energy ray The hardening type adhesive is preferably a visible light hardening type adhesive.

"Active Energy Ray Hardening Type"

In the active energy ray-curable adhesive, after bonding the polarizer and the transparent protective film, the active energy ray (electron rays, ultraviolet rays, visible light, etc.) is irradiated, and the active energy ray-curable adhesive is hardened to form an adhesive layer . The irradiation direction of active energy rays (electron rays, ultraviolet rays, visible rays, etc.) can be irradiated from any suitable direction. It is more desirable to irradiate from the side of the transparent protective film. If irradiated from the polarizer side, the polarizer may deteriorate due to active energy rays (electron rays, ultraviolet rays, visible rays, etc.).

"Electronic beam hardening type"

In the electron beam curing type, as long as the irradiation condition of the electron beam is a condition that can cure the aforementioned active energy ray curing type adhesive, any appropriate conditions can be adopted. For example, for electron beam irradiation, the acceleration voltage should be 5 kV to 300 kV, and more preferably 10 kV to 250 kV. When the acceleration voltage is less than 5kV, the electron beam cannot reach the adhesive and there is a risk of insufficient hardening. If the acceleration voltage is greater than 300kV, the penetration force of the sample is too strong, which may damage the transparent protective film or the polarizer. The irradiation dose is 5~100kGy, and more preferably 10~75kGy. When the irradiation dose is less than 5kGy, the adhesive will not harden If it is more than 100kGy, it will cause damage to the transparent protective film or polarizer, and reduce the mechanical strength or yellowing, and the predetermined optical characteristics cannot be obtained.

Electron beam irradiation is usually carried out in an inert gas, but However, if necessary, it can also be carried out in the atmosphere or under the condition of introducing a small amount of oxygen. Although it differs according to the material of the transparent protective film, by introducing oxygen appropriately, the surface of the transparent protective film initially irradiated with electron beams intentionally produces oxygen suppression, and can prevent damage to the transparent protective film and can effectively The electron beam is irradiated only to the adhesive.

"Ultraviolet curing type, visible light curing type"

In the manufacturing method of the polarizing film of the present invention, the active energy ray preferably includes visible light with a wavelength range of 380 nm to 450 nm, especially the active energy line with the largest exposure to visible light with a wavelength range of 380 nm to 450 nm. In the ultraviolet curing type and the visible light curing type, when using a transparent protective film (ultraviolet-transmissive transparent protective film) that has been provided with ultraviolet absorption capacity, the light with a wavelength shorter than 380nm is generally absorbed, so the light with a wavelength shorter than 380nm It will not reach the active energy ray hardening type adhesive without helping its polymerization reaction. Furthermore, the light with a wavelength shorter than 380 nm absorbed by the transparent protective film will be converted into heat, and the transparent protective film itself will generate heat, and cause the curling, wrinkling and other defects of the polarizing film. Therefore, when the ultraviolet curing type and the visible light curing type are used in the present invention, the active energy ray generating device should preferably use a device that does not emit light with a wavelength shorter than 380 nm. More specifically, the cumulative illuminance of the wavelength range 380 to 440 nm and The ratio of the cumulative illuminance in the wavelength range 250~370nm should be 100:0~100:50, and more preferably It is 100:0~100:40. The active energy ray of the present invention is preferably a metal halide lamp enclosed with gallium and an LED light source with a light emitting wavelength range of 380-440 nm. Or, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, incandescent lamps, xenon lamps, halogen lamps, carbon arc lamps, metal halogen lamps, fluorescent lamps, tungsten filament lamps, gallium lamps, excimer lasers or Sunlight and other light sources including ultraviolet rays and visible rays can also be used with a band-pass filter to block ultraviolet rays with a wavelength shorter than 380nm. In order to improve the adhesion performance of the adhesive layer between the polarizer and the transparent protective film, and to prevent the curling of the polarizing film, it is advisable to use the following active energy ray, that is: use a metal halide lamp enclosed in gallium and pass through to block wavelengths shorter than 380nm The active energy line obtained by the bandpass filter of light, or the active energy line with a wavelength of 405 nm obtained by using an LED light source.

Suitable for irradiation in ultraviolet curing type or visible light curing type The active energy ray-curable adhesive is heated before ultraviolet or visible light (heating before irradiation). At this time, the heating is preferably 40°C or higher, and more preferably 50°C or higher. In addition, it is also suitable to heat the active energy ray-curable adhesive after irradiating ultraviolet rays or visible rays (heating after irradiation). In this case, the temperature is preferably 40°C or higher, and more preferably 50°C or higher.

In particular, the active energy ray-curable adhesive of the present invention can be suitably used in the case of forming an adhesive layer for adhering a polarizer and a transparent protective film having a light transmittance of less than 5% at a wavelength of 365 nm. Here, the active energy ray-curable adhesive of the present invention contains the photopolymerization initiator of the general formula (1), whereby the transparent protective film with UV absorption ability can be irradiated with ultraviolet rays to harden to form an adhesive layer . Accordingly, even though Yu has already laminated transparent protective films with UV absorption In the polarizing films on both sides of the optical member, the adhesive layer can also be hardened. However, as a matter of course, the adhesive layer can also be hardened in a polarizing film that has been laminated with a transparent protective film that does not have UV absorption capability. In addition, the so-called transparent protective film with UV absorption capability means a transparent protective film whose transmittance to light at 380 nm is less than 10%.

The method of imparting UV absorption ability to the transparent protective film may include, for example, a method of containing an ultraviolet absorber in the transparent protective film, or a method of laminating a surface treatment layer containing an ultraviolet absorber on the surface of the transparent protective film.

For example, specific examples of ultraviolet absorbers can be cited as: Conventionally known oxygen diphenyl ketone compounds, benzotriazole compounds, salicylate compounds, diphenyl ketone compounds, cyanoacrylate compounds, nickel complex compounds, triazine compounds, etc. .

After the polarizer and the transparent protective film are bonded, active energy rays (electron rays, ultraviolet rays, visible rays, etc.) are irradiated, and the active energy ray hardening type adhesive is hardened to form an adhesive layer. The irradiation direction of active energy rays (electron rays, ultraviolet rays, visible rays, etc.) can be irradiated from any suitable direction. It is more desirable to irradiate from the side of the transparent protective film. If irradiated from the polarizer side, the polarizer may deteriorate due to active energy rays (electron rays, ultraviolet rays, visible rays, etc.).

"Thermosetting"

On the other hand, in the thermosetting adhesive, after the polarizer and the transparent protective film are bonded, by heating, the polymerization is started by the thermal polymerization initiator, and a hardened layer is formed. The heating temperature can be set according to the thermal polymerization initiator It is fixed, but it is 60~200℃, and preferably 80~150℃.

When manufacturing the polarizing film of the present invention by a continuous wire, the wire Although the speed varies according to the curing time of the adhesive, it is preferably 1 to 500 m/min, and more preferably 5 to 300 m/min, and further preferably 10 to 100 m/min. When the linear speed is too small, it lacks productivity, or the damage to the transparent protective film is too great to make a polarizing film that can withstand durability tests. When the linear velocity is too high, the curing of the adhesive is insufficient, and the target adhesiveness may not be obtained.

In addition, the polarizing film of the present invention is hard through the aforementioned active energy rays The adhesive layer formed by the hardened layer of the chemical adhesive bonds the polarizer and the transparent protective film. However, an easy adhesive layer may be provided between the transparent protective film and the adhesive layer. For example, the easy-adhesion layer can be formed by having a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a polysiloxane system, a polyamide skeleton, a polyimide skeleton, polyethylene It is formed by various resins such as alcohol skeleton. These polymer resins can be used alone or in combination of two or more. In addition, other additives may be added to the formation of the easy-adhesion layer. Specifically, stabilizers such as adhesion-imparting agents, ultraviolet absorbers, antioxidants, and heat-resistant stabilizers can also be used.

The easy-adhesive layer is usually provided in advance on the transparent protective film, and the easy-adhesive layer side of the transparent protective film and the polarizer are bonded by an adhesive layer. The formation of the easy-adhesion layer is performed by coating and drying the forming material of the easy-adhesion layer on the transparent protective film by a known technique. The forming material of the easy-adhesion layer is usually adjusted to a solution having an appropriate concentration after taking into consideration the thickness after drying, the smoothness of coating, etc. The thickness of the easy-adhesion layer after drying should be 0.01~5μm, and more preferably 0.02~2μm, further preferably 0.05~1μm. In addition, the easy-adhesion layer may be provided with a plurality of layers, however, at this time, the total thickness of the easy-adhesion layer is also preferably within the aforementioned range.

<polarizer>

There are no special restrictions on polarizers, and various polarizers can be used. For example, the polarizer may include, for example, adsorbing a dichroic material such as iodine or a dichroic dye to a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, and ethylene. Vinyl acetate copolymers are hydrophilic polymer films such as partially saponified films and uniaxially stretched, polyene oriented films such as dehydration treatment of polyvinyl alcohol or dehydrochlorination treatment of polyvinyl chloride. Among these, a polarizer composed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is also suitable. The thickness of these polarizers is not particularly limited, however, it is generally below 80 μm.

For example, a polarizing member in which a polyvinyl alcohol-based film is dyed by iodine and uniaxially extended can be produced as follows: that is, dyed by dipping polyvinyl alcohol in an aqueous solution of iodine and extended to the original length 3~7 times. If necessary, it can also be immersed in an aqueous solution of boric acid or potassium iodide. Furthermore, if necessary, the polyvinyl alcohol-based film may be immersed in water and washed before being dyed. By washing the polyvinyl alcohol-based film with water, the dirt or anti-caking agent on the surface of the polyvinyl alcohol-based film can be washed. In addition, by swelling the polyvinyl alcohol-based film, it also prevents uneven dyeing. Uniform effect. The extension can be carried out after dyeing with iodine, or it can be dyed on one side and extended on the other side, or it can be dyed with iodine after the extension. It can also be extended in aqueous solutions such as boric acid or potassium iodide or in a water bath.

In addition, the hardening type adhesive of the present invention has a thickness of 10 μm When the following thin polarizer is used as a polarizer, its effect can be clearly exhibited (satisfying the optical durability under severe environments under high temperature and high humidity). Compared with polarizers with a thickness greater than 10 μm, the polarizers with a thickness of 10 μm or less have a relatively large influence on moisture, and have insufficient optical durability under high-temperature and high-humidity environments, and are likely to cause an increase in transmittance or a decrease in polarization. . That is, when the polarizer with the overall water absorption rate of 10% by weight or less according to the present invention is laminated to the polarizer with a thickness of 10 μm or less, by suppressing the movement of water toward the polarizer in an environment under severe high temperature and high humidity, it is obvious To suppress deterioration of optical durability such as increase in transmittance of polarizing film and decrease in polarization degree. From the viewpoint of thinning, the thickness of the polarizer is preferably 1 to 7 μm. Such a thin polarizer has less unevenness in thickness and excellent recognizability, and has less dimensional change. Furthermore, the thickness of the polarizing film is also ideal for achieving thinness.

Representatives, the thin polarizers can be listed as follows: Kazakhstan 51-069644 or JP 2000-338329, WO2010/100917, PCT/JP2010/001460, Japanese Patent Application No. 2010-269002 or Japanese Patent Application No. 2010-263692 Thin polarizing film. Such thin polarizing films can be obtained by a manufacturing method including the following steps: a step of extending a layer of a polyvinyl alcohol-based resin (hereinafter also referred to as PVA-based resin) and a resin substrate for extension in a state of a laminate; And dyeing steps. According to this manufacturing method, even if the PVA-based resin layer is thin, by supporting the resin substrate for stretching, there is no problem such as cracking due to stretching and the like, and it can be stretched.

In the manufacturing method including the step of extending in the state of the laminate and the step of dyeing, if it can be extended to a high magnification to improve the polarization performance From a viewpoint, the aforementioned thin polarizing film should also be included in the specification disclosed in WO2010/100917, PCT/JP2010/001460, Japanese Patent Application No. 2010-269002, or Japanese Patent Application No. 2010-263692. The preparation method of the step of extending in the aqueous solution of boric acid, in particular, it is preferable to include the step of auxiliary air extension before extension in the aqueous solution of boric acid as disclosed in the specification of Japanese Patent Application No. 2010-269002 or the specification of Japanese Patent Application No. 2010-263692 Derived from the system.

The thinness disclosed in the aforementioned PCT/JP2010/001460 specification Type high-performance polarizing film is integrally formed on the resin substrate, and is composed of PVA-based resin that has already oriented the dichroic substance, and has a thickness of 7 μm or less, and has a single transmittance of 42.0% or more and a degree of polarization The optical characteristics are above 99.95%.

The aforementioned thin high-performance polarizing film can be manufactured as follows, namely: By coating and drying the PVA-based resin, a PVA-based resin layer is formed on a resin substrate having a thickness of at least 20 μm, and the generated PVA-based resin layer is immersed in the dyeing solution of the dichroic substance, and the dichroic The sexual substance is adsorbed on the PVA-based resin layer, and in the boric acid aqueous solution, the PVA-based resin layer on which the dichroic substance has been adsorbed and the resin base material are integrally extended to a total extension ratio of more than 5 times the original length.

Also, a manufacturing method that contains already oriented dichroic substances A laminated film of a high-performance polarizing film, which includes the following steps, that is, a step of forming a laminated film including a resin base material and a PVA-based resin layer, and the resin base material has at least 20 μm The thickness of the PVA-based resin layer is due to the fact that one side of the resin substrate will contain PVA It is formed by coating and drying an aqueous solution of a resin; the adsorption step is performed by immersing the laminate film including the resin base material and the PVA-based resin layer formed on one side of the resin base material into a dye containing a dichroic substance In the solution, the PVA-based resin layer contained in the laminate film adsorbs the dichroic substance; the extension step is in a boric acid aqueous solution to allow the aforementioned laminate film containing the PVA-based resin layer that has adsorbed the dichroic substance to The stretching ratio is stretched by 5 times or more of the original length; and a step of manufacturing a laminate film, which is formed on the resin base by integrally extending the PVA-based resin layer that has adsorbed the dichroic substance and the resin substrate The thin high-function polarizing film is formed on one side of the material, and the thin high-function polarizing film is composed of a PVA-based resin layer that has oriented a dichroic substance, has a thickness of 7 μm or less, and has a monomer transmittance of 42.0% The above and the optical property of the polarization degree is 99.95% or more; thereby, the aforementioned thin high-performance polarizing film can be manufactured.

The thin polarizing film of the aforementioned Japanese Patent Application No. 2010-269002 or Japanese Patent Application No. 2010-263692 is a continuous base polarizing film composed of PVA-based resins which have orientated dichroic substances, and contains the film formed in The laminated body of the PVA-based resin layer of the amorphous ester-based thermoplastic resin substrate is extended by two-step stretching step, thereby making the thickness less than 10 μm, and the two-step extension step is assisted by air-assisted extension and boric acid Consists of extension in water. When the transmittance of the monomer is T and the polarization degree is P, the thin polarizing film is preferably made to satisfy P>-(10 ^{0.929T-42.4-1} )×100 (however, T<42.3) and P≧99.9 (However, the optical characteristics of the condition T≧42.3).

Specifically, the thin polarizing film may include the following steps It is manufactured by a method of manufacturing a thin polarizing film in one step, that is, in one step, it is formed by stretching the PVA-based resin layer of an amorphous ester-based thermoplastic resin substrate that has been deposited on a continuous base material at high temperature in the air to generate The extended intermediate product composed of the oriented PVA-based resin layer; a step of generating a dichromatic substance (preferably iodine or iodine and organic) by adsorbing the dichroic substance of the extended intermediate product A mixture of dyes) a colored intermediate product composed of an oriented PVA-based resin layer; and a step of generating a PVA-based resin layer by orienting a dichroic substance by extending the colored intermediate product in boric acid water A polarizing film with a thickness of 10 μm or less.

In this manufacturing method, high temperature extension in the air and boric acid water are used The total stretching ratio of the PVA-based resin layer that has been filmed on the amorphous ester-based thermoplastic resin substrate for stretching is preferably 5 times or more. The liquid temperature of the boric acid aqueous solution for extension in boric acid water can be made to be above 60°C. Before extending the colored intermediate product in the aqueous solution of boric acid, the colored intermediate product is preferably subjected to an insolubilization treatment. In this case, it is preferably performed by immersing the aforementioned colored intermediate product in an aqueous solution of boric acid having a liquid temperature not higher than 40°C. The aforementioned amorphous ester-based thermoplastic resin substrate can be made of copolymerized polyethylene terephthalate copolymerized with isophthalic acid and copolymerized polyethylene terephthalate copolymerized with cyclohexane dimethanol Or other copolymerized polyethylene terephthalate, amorphous polyethylene terephthalate, and preferably made of transparent resin, the thickness of which can be made up to 7 times the thickness of the film-formed PVA-based resin layer . In addition, the stretching ratio of the high-temperature stretching in the air is preferably 3.5 times or less, and the stretching temperature of the high-temperature stretching in the air is preferably higher than the glass transition temperature of the PVA-based resin, specifically in the range of 95°C to 150°C. When the high-temperature stretching in the air is carried out by uniaxial stretching at the free end, the film has been formed in the amorphous The total stretching ratio of the PVA-based resin layer of the ester-based thermoplastic resin substrate is preferably 5 times or more and 7.5 times or less. In addition, when performing high-temperature stretching in the air by uniaxial stretching at the fixed end, the total stretching ratio of the PVA-based resin layer that has been formed on the amorphous ester-based thermoplastic resin substrate is preferably 5 times or more and 8.5 times or less.

More specifically, a thin polarizing film can be manufactured by the following method.

The manufacturing operation has made the isophthalic acid 6mol% copolymerized isophthalic acid copolymerized polyethylene terephthalate (non-crystalline PET) continuous base material of the base material. The glass transition temperature of amorphous PET is 75℃. A laminate composed of an amorphous PET substrate of a continuous base material and a polyvinyl alcohol (PVA) layer was prepared as follows. Incidentally, the glass transition temperature of PVA is 80°C.

Prepare an amorphous PET substrate with a thickness of 200 μm, and a PVA aqueous solution with a concentration of 4 to 5% that has dissolved PVA powder with a polymerization degree of 1000 or more and a saponification degree of 99% or more in water. Next, the PVA aqueous solution was applied to a 200 μm thick amorphous PET substrate, and dried at a temperature of 50 to 60° C., and a laminate having a 7 μm thick PVA layer formed on the amorphous PET substrate was prepared.

The laminate including the PVA layer with a thickness of 7 μm was subjected to the following steps including the two-step extension step of air-assisted extension and boric acid water extension, and a thin high-function polarizing film with a thickness of 3 μm was manufactured. By the air-assisted extension step of the first stage, the laminate including the 7 μm thick PVA layer and the amorphous PET substrate are extended integrally, and an extended laminate including the 5 μm thick PVA layer is produced. Specifically, the extension laminate is an extension device equipped with a laminate including a 7 μm thick PVA layer placed in an oven, and uniaxially extended at a free end to an extension ratio of 1.8 times, and the oven is set to 130 ℃ extended temperature environment. By this extension process, the PVA included in the extension laminate The layer changes to a 5 μm thick PVA layer with PVA molecules already oriented.

Second, through the dyeing step, the production has already adsorbed iodine to PVA The colored layered body of PVA layer with 5μm thickness oriented by molecules. Specifically, the colored laminate is to immerse the stretch laminate in a dyeing solution containing iodine and potassium iodide at a liquid temperature of 30°C for an arbitrary period of time, so as to make the single-component transmittance of the PVA layer constituting the high-functional polarizing film finally generated The composition is 40% to 44%, thereby allowing iodine to be adsorbed on the PVA layer included in the elongated laminate. In this step, the dyeing solution uses water as a solvent, and the iodine concentration is in the range of 0.12 to 0.30% by weight, and the potassium iodide concentration is in the range of 0.7 to 2.1% by weight. The concentration ratio of iodine to potassium iodide is 1 to 7. By the way, when iodine is to be dissolved in water, potassium iodide must be used. More specifically, by immersing the extended laminate in a dyeing solution having an iodine concentration of 0.30% by weight and a potassium iodide concentration of 2.1% by weight for 60 seconds, a 5 μm-thick PVA layer having iodine adsorbed to PVA molecules has been formed. Colored laminate.

Furthermore, through the boric acid water extension step of the second paragraph, the coloring The laminate is further extended integrally with the amorphous PET substrate, and an optical thin-film laminate including a PVA layer constituting a high-functional polarizing film having a thickness of 3 μm is produced. Specifically, the optical film laminate is an extension device equipped with a colored laminate placed in a processing device, and is uniaxially extended at a free end to an extension magnification of 3.3 times, and the processing device is set to include boric acid and potassium iodide Boric acid aqueous solution with a liquid temperature range of 60~85℃. More specifically, the liquid temperature of the aqueous solution of boric acid is 65°C. The boric acid content was 4 parts by weight with respect to 100 parts by weight of water, and the potassium iodide content was 5 parts by weight with respect to 100 parts by weight of water. In this step, the color lamination body with adjusted iodine adsorption capacity is first dipped Stain in boric acid aqueous solution for 5~10 seconds. Then, the colored layered product is directly passed between rollers with different peripheral speeds of the complex device belonging to the stretching device provided in the processing device, and it takes 30 to 90 seconds to uniaxially stretch to a stretch magnification of 3.3 times at the free end. By this extension treatment, the PVA layer included in the colored laminate was changed to adsorbed iodine as a polyiodide ion complex and oriented multiple times in a direction of a 3 μm thick PVA layer. The PVA layer constitutes a high-performance polarizing film of an optical thin film laminate.

Although it is not a necessary step for the manufacture of optical film laminates However, it is advisable to take out the optical film laminate from the aqueous solution of boric acid by the washing step, and wash the boric acid attached to the surface of the 3 μm thick PVA layer that has been formed on the amorphous PET substrate by the aqueous potassium iodide solution. Then, the dried optical film laminate is dried by a drying step using warm air at 60°C. In addition, the washing step is a step to solve the appearance defects such as boric acid precipitation.

Although it is also not necessary for the manufacture of optical film laminates However, it is also possible to apply a bonding agent on the surface of the 3 μm thick PVA layer of the amorphous PET substrate that has been film-formed by bonding and/or transfer steps, while bonding 80 μm thick triethyl acetylene on the one side After the cellulose film, the amorphous PET substrate was peeled off, and the 3 μm thick PVA layer was transferred to an 80 μm thick triacetyl cellulose film.

[Other steps]

In addition to the aforementioned steps, the aforementioned method of manufacturing the thin polarizing film may include other steps. For example, other steps may include, for example, an insolubilization step, a cross-linking step, and a drying (adjustment of water content) step. Other steps can be arbitrary At the right time.

Representatively, the aforementioned insolubilization step is performed by immersing the PVA-based resin layer in an aqueous solution of boric acid. By performing insolubilization treatment, water resistance can be imparted to the PVA-based resin layer. The concentration of the boric acid aqueous solution is preferably 1 part by weight to 4 parts by weight relative to 100 parts by weight of water. The liquid temperature of the insolubilization bath (boric acid aqueous solution) is preferably 20°C to 50°C. It is preferable that the insolubilization step is performed after the layered body is produced and before the dyeing step or the water extension step.

Representatively, the aforementioned cross-linking step is performed by immersing the PVA-based resin layer in an aqueous solution of boric acid. By performing the cross-linking treatment, the PVA-based resin layer can be given water resistance. The concentration of the boric acid aqueous solution is preferably 1 part by weight to 4 parts by weight relative to 100 parts by weight of water. In addition, when the cross-linking step is performed after the aforementioned dyeing step, it is more preferable to blend the iodide. By blending iodide, the elution of iodine that has been adsorbed to the PVA-based resin layer can be suppressed. The blending amount of iodide is preferably 1 part by weight to 5 parts by weight relative to 100 parts by weight of water. Specific examples of iodide are as described above. The liquid temperature of the cross-linking bath (boric acid aqueous solution) is preferably 20°C to 50°C. Preferably, the cross-linking step is performed before the second boric acid water extension step. In an ideal embodiment, the dyeing step, the cross-linking step, and the second boric acid water extension step are performed in this order.

<transparent protective film>

The material forming the transparent protective film provided on one or both sides of the polarizer is preferably a material excellent in transparency, mechanical strength, thermal stability, moisture blocking property, isotropy and the like. Examples include polyester-based polymers such as polyethylene terephthalate or polyethylene naphthalate, cellulose-based polymers such as diethyl cellulose or triethylene cellulose, and polymethine Methacrylate Acrylic polymer, polystyrene or acrylonitrile. Styrene-based polymers such as styrene copolymers (AS resins) and polycarbonate-based polymers. Also, examples of the polymer forming the transparent protective film are: polyethylene, polypropylene, polyolefin having a ring system or norbornene structure, ethylene. Propylene copolymers such as polyolefin-based polymers, vinyl chloride-based polymers, nylon or aromatic polyamide-based amide-based polymers, amide-imide-based polymers, lanyard-based polymers, polyether lanyard-based polymers, Polyetheretherketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, dichlorovinylidene polymer, ethylene butyraldehyde polymer, aryl ester polymer, polyoxymethylene polymer, epoxy It is a polymer or a blend of the aforementioned polymers. The transparent protective film may also contain more than one kind of any suitable additives. For example, the additives may include, for example, ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, anti-coloring agents, flame retardants, nucleating agents, anti-static agents, pigments, coloring agents, and the like. The content of the aforementioned thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, and more preferably 50 to 99% by weight, further preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. When the content of the thermoplastic resin in the transparent protective film is 50% by weight or less, there is a possibility that the high transparency originally possessed by the thermoplastic resin and the like may not be sufficiently exhibited.

In addition, the transparent protective film may be exemplified by Japanese Patent Application The polymer film disclosed in Gazette No. 2001-343529 (WO01/37007), for example, a thermoplastic resin containing (A) a substituted and/or unsubstituted imide group in the side chain and (B) a substituted and/or side chain Resin composition of unsubstituted phenyl and nitrile based thermoplastic resin. Specific examples include, for example, containing alternating copolymers consisting of isobutylene and N-methylmaleimide and acrylonitrile. Styrene Film of resin composition of olefin copolymer. As the film, a film composed of a mixed extruded product of a resin composition or the like can be used. The phase difference of these films is small, and the photoelastic coefficient is small. Therefore, the unevenness caused by the strain of the polarizing film can be solved. Also, because the moisture permeability is small, the humidification durability is excellent.

In the polarizing film, the transparent protective film preferably has a moisture permeability of 150 g/m ² /24h or less. With the aforementioned structure, it is difficult for moisture in the air to enter the polarizing film, and the change in the water content of the polarizing film itself can be suppressed. As a result, the curling or dimensional change of the polarizing film due to the storage environment can be suppressed.

The material forming the transparent protective film provided on one or both sides of the polarizer is preferably a material with excellent transparency, mechanical strength, thermal stability, moisture blocking property, isotropy, etc. 150 g/m ² /24h or less, and particularly preferably 140 g/m ² /24h or less, and more preferably 120 g/m ² /24h or less. The water vapor permeability can be obtained by the method disclosed in the embodiment.

For example, a transparent protective film that satisfies the aforementioned low moisture permeability The forming material can be used: polyester resins such as polyethylene terephthalate or polyethylene naphthalate; polycarbonate resins; aryl ester resins; nylon or aromatic polyamide resins such as polyamide resins; such as Polyethylene, polypropylene, ethylene. A polyolefin polymer of a propylene copolymer, a cyclic olefin resin having a ring system or norbornene structure, a (meth)acrylic resin, or a mixture of these. Among the aforementioned resins, polycarbonate resins, cyclic polyolefin resins, and (meth)acrylic resins are also preferred, and cyclic polyolefin resins and (meth)acrylic resins are particularly preferred.

The thickness of the transparent protective film can be appropriately determined. Generally speaking, From the viewpoint of workability such as strength and handleability, and thin layer properties, it is 1 to 100 μm. In particular, it is preferably 1 to 80 μm, and more preferably 3 to 60 μm.

In addition, when the transparent protective films are provided on both sides of the polarizer, a transparent protective film composed of the same polymer material on the surface and a transparent protective film composed of different polymer materials can also be used.

A functional layer such as a hard coat layer, an anti-reflection layer, an anti-adhesive layer, a diffusion layer, or an anti-glare layer may be provided on the surface of the transparent protective film that is not attached to the polarizer. In addition, the functional layer such as the hard coat layer, the anti-reflection layer, the anti-sticking layer, the diffusion layer, or the anti-glare layer can be provided not only on the transparent protective film itself, but also on a transparent protective film.

<optical film>

The polarizing film of the present invention can be used as an optical film laminated with other optical layers in practical use. The optical layer is not particularly limited. For example, one or more reflective plates, semi-transmissive plates, retardation plates (including 1/2 or 1/4 wavelength plates) or viewing angle compensation can be used Thin films and the like are used for optical layers formed in liquid crystal display devices and the like. It is particularly desirable to construct a reflective polarizing film or a semi-transmissive polarizing film configured as a laminated polarizer film or a semi-transmissive reflective plate of the present invention, an elliptical polarizing film or a circularly polarized light configured as a polarizing film further laminated as a retardation plate The film, the wide viewing angle polarizing film configured to layer a viewing angle compensation film on the polarizing film, or the polarizing film configured to layer a brightness enhancement film on the polarizing film.

The optical films that have been laminated on the polarizing film can also be individually laminated in sequence due to the manufacturing process of liquid crystal display devices, etc. However, the optical film that is laminated in advance to produce an optical film has the advantages of excellent quality stability, assembly work, and the like, and can improve the manufacturing steps of the liquid crystal display device and the like. For the lamination, an appropriate bonding mechanism such as an adhesive layer can be used. When attaching the aforementioned polarizing film or other optical film, the optical axes of these can be arranged at an appropriate angle according to the target phase difference characteristics and the like.

The polarizing film or the optical film laminated with at least one polarizing film may also be provided with an adhesive layer for adhering to other members such as liquid crystal cells. The adhesive that forms the adhesive layer is not particularly limited. For example, acrylic polymers, polysiloxane polymers, polyesters, polyurethanes, polyamides, Polymers such as ether, fluorine or rubber are used as adhesives for basic polymers. In particular, adhesives that are excellent in optical transparency like acrylic adhesives, exhibit moderate wettability, cohesiveness, and adhesive properties, and have excellent weather resistance, heat resistance, etc. are preferably used.

The adhesive layer can also be made as an overlapping layer of different composition or type, etc. and provided on one side or both sides of the polarizing film or the optical film. In addition, when it is provided on both sides, adhesive layers of different compositions, types, or thicknesses may be formed on the surface of the polarizing film or the optical film. The thickness of the adhesive layer can be appropriately determined according to the purpose of use or adhesion, etc. However, it is generally 1 to 500 μm, and preferably 1 to 200 μm, especially 1 to 100 μm.

During the period until it is put into practical use, for the purpose of preventing contamination, etc., the exposed surface of the adhesive layer is temporarily adhered to cover the partition. This prevents contact with the adhesive layer under conventional processing conditions. In addition to the aforementioned thickness conditions, the separator can be used, for example, by a suitable release agent such as polysiloxane-based or long-chain alkyl-based, fluorine-based or molybdenum sulfide, to separate the plastic film, rubber sheet, Appropriate sheet materials such as paper, cloth, non-woven fabric, mesh, foamed sheet or metal foil, laminates of these, etc. are subjected to coating treatment, etc., which are in conformity with conventional standards.

<Image display device>

The polarizing film or optical film of the present invention can be preferably used for forming various devices such as liquid crystal display devices. The formation of the liquid crystal display device can be carried out in accordance with previous standards. That is, in general, a liquid crystal display device is formed by appropriately assembling a liquid crystal cell and a polarizing film or an optical film, and as necessary a lighting system and other components, and incorporating a driving circuit, etc. However, in the present invention, except There is no special restriction on the use of the polarizing film or optical film according to the present invention, and it can follow the previous standards. For example, the liquid crystal cell may use any type such as TN type, STN type, or π type.

Appropriate liquid crystal display devices such as a liquid crystal display device in which a polarizing film or an optical film is arranged on one or both sides of a liquid crystal cell, or a backlight or a reflective plate used in an illumination system can be formed. At this time, the polarizing film or the optical film according to the present invention can be disposed on one side or both sides of the liquid crystal cell. When polarizing films or optical films are provided on both sides, these may be the same or different. Furthermore, in the formation of the liquid crystal display device, for example, appropriate parts such as a diffusion plate, an anti-glare layer, an anti-reflection film, a protection plate, a prism array, a lens array sheet, a light diffusion plate, a backlight, etc. can be used Arrange one layer or more than two layers in appropriate locations.

Examples

The embodiments of the present invention are disclosed below, however, the embodiments of the present invention are not limited to these.

<Production of polarizers>

A 75 μm thick polyvinyl alcohol film with an average degree of polymerization of 2400 and a degree of saponification of 99.9 mol% was immersed in warm water at 30° C. for 60 seconds and swelled. Next, it was immersed in an aqueous solution of 0.3% concentration of iodine/potassium iodide (weight ratio=0.5/8), and the film was dyed while being extended to 3.5 times. Then, stretching is carried out in an aqueous solution of boric acid ester at 65° C., so that the total stretching ratio becomes 6 times. After the extension, drying was carried out in an oven at 40° C. for 3 minutes, and a PVA-based polarizer X (thickness 23 μm) was prepared.

<transparent protective film>

Transparent protective film 1: without saponification, corona treatment, etc., a triacetyl cellulose film with a thickness of 60 μm (moisture permeability 530 g/m ² /24h) (marked as TAC in Table 1) was used.

Transparent protective film 2: (meth)acrylic resin having a lactone ring structure with a thickness of 40 μm (moisture permeability 96 g/m ² /24h) is used after corona treatment (marked as acrylic in Table 1).

Transparent protective film 3: cyclic polyolefin film with a thickness of 55 μm (manufactured by Zeon Corporation: ZEONOR, moisture permeability 11 g/m ² /24h) and used for corona treatment (marked as COP in Table 1) .

<Moisture permeability of transparent protective film>

The moisture permeability is measured in accordance with the moisture permeability test (moisture permeability cup method) of JIS Z0208. Place the sample that has been cut into a diameter of 60mm in a moisture-permeable cup that has been placed with about 15g of calcium chloride, and put it into a thermostat with a temperature of 40°C and a humidity of 90%RH, and measure the chlorine before and after 24 hours. By increasing the weight of calcium chloride, the moisture permeability (g/m ² /24h) was determined.

<active energy line>

The active energy ray uses visible light (metal halide lamp enclosed in gallium), irradiation device: Fusion UV Systems, Inc. Light HAMMER10, valve: V valve, peak illuminance: 1600mW/cm ² , cumulative exposure 1000mJ/cm ² ( (Wavelength 380~440nm). In addition, the illuminance of visible light is measured using the Sola-Check system manufactured by Solatell.

Examples 1 to 4 and Comparative Examples 1 to 5

(Preparation of active energy ray hardening adhesive)

According to the blending table disclosed in Table 1, the components were mixed and stirred at 50° C. for 1 hour, and the active energy ray-curable adhesives related to Example 1 and Comparative Example 1 were prepared. In addition, the viscosity of the active energy ray-curable adhesive in Example 1 is 95 cp (25°C), and the viscosity of the active energy ray-curable adhesive in Comparative Example 1 is 45 cp (25°C).

(Production of polarizing film)

Using the MCD coater (manufactured by Fuji Machinery Co., Ltd.) (single cell shape: honeycomb shape, gravure roll line number: 1000 pcs/inch, rotation speed 140%/pair line speed), the above-mentioned implementation of the above-mentioned transparent protective film The active energy ray hardening type adhesive of the example or the comparative example is coated to a thickness of 0.7 μm, and is bonded to both sides of the polarizer X by a roller machine. Then, using an IR heater, the self-adhesive transparent protective film side (both sides) is heated to 50° C., and the aforementioned visible light is irradiated to both sides to make the active energy ray-curable adhesive agent related to the aforementioned example or comparative example. After curing, it is dried by hot air at 70°C for 3 minutes, and a polarizing film having transparent protective films on both sides of the polarizing member is prepared. The linear speed of bonding is carried out by 25m/min.

The polarizing film is produced for the three types of transparent protective films 1 to 3 mentioned above.

The following evaluation was performed on the polarizing film produced by the foregoing examples and comparative examples. Table 1 shows the evaluation results. In addition, in the evaluation of the humidification durability and the subsequent water resistance, the same polarizing film was separately prepared.

<overall water absorption rate>

The hardening adhesive for polarizing film used in each example was used, sandwiched by two pieces of glass provided with a 100 μm separator, and cured with the same active energy conditions as in the example to modulate a thickness of 100 μm. Agent layer (hardened). Use this as a sample. Make the weight of the sample M1g. The sample M1g was immersed in pure water at 23°C for 24 hours. Then, after taking out from pure water and wiping with a dry cloth, the weight (M2g) of the sample was measured again within 1 minute. The overall water absorption rate is calculated from these results by the following formula, namely: Formula: {(M2-M1)/M1}×100(%).

<hardening shrinkage>

It is measured by the hardening shrinkage sensor "resin hardening shrinkage stress measuring device EU201C" manufactured by Shengtieke. Specifically, by the method disclosed in JP-A 2013-104869, the hardening shrinkage ratio is calculated. In addition, the curing shrinkage rate of the cured product formed from the active energy ray hardening type adhesive of Example 1 is 8.9%, and the curing shrinkage rate of the cured product formed from the active energy ray hardening type adhesive of Related Example 1 is 11.9%.

<adhesion>

The polarizing film prepared in each example was cut out to a size parallel to the extending direction of the polarizing member of 200 mm and a straight direction of 20 mm, and by a cutting knife, A cut is added between the transparent protective film and the polarizer, and the polarizing film is adhered to the glass plate. With a universal testing machine (TENSILON), the transparent protective film and the polarizer were peeled at a peeling speed of 500 mm/min in the direction of 90 degrees, and the peel strength was measured. In addition, the infrared absorption spectrum of the peeled surface after peeling was measured by the ATR method, and the peeling interface was evaluated according to the following criteria.

A: Cohesive destruction of transparent protective film

B: Interface peeling between transparent protective film/adhesive layer

C: Interface peeling between adhesive layer/polarizer

D: Cohesive destruction of polarizer

In the aforementioned criteria, A and D mean that the adhesive force is more than the cohesive force of the film, and therefore, the adhesive force is very excellent. On the other hand, B and C mean that the adhesive force at the interface of the transparent protective film/adhesive layer (adhesive layer/polarizer) is insufficient (adhesive force is poor). Considering these and making the adhesive force when it belongs to A or D ○, it will belong to A. B (simultaneously produces "agglomeration destruction of transparent protective film" and "interfacial peeling between transparent protective film/adhesive layer") or A. C (At the same time, the "cohesive failure of the transparent protective film" and "the peeling of the interface between the adhesive layer and the polarizer") are made into △, and the adhesion force of B or C is made into ×.

<Humidity Durability: Measurement of Changes in Transmittance and Polarization of Monomers>

By the same method as in the examples and comparative examples, a polarizing film having transparent protective films 2 and 3 as transparent protective films laminated on each side of the polarizer was prepared as a sample. This polarizing film (sample) was put into a constant temperature and humidity machine at 85°C/85%RH for 500 hours. Use a spectrophotometer with an integrating sphere (Dot-3c from Murakami Color Technology Research Institute) to measure the Monomer transmittance and polarization degree of the polarizing film after input, and calculate: the amount of change in monomer transmittance (△T:%) = (monomer transmittance after input (%))-(single before input Volume transmittance (%)); the amount of change in polarization (△P:%) = (polarization after input (%))-(polarization before input (%)).

In addition, the polarization degree P is obtained by stacking two identical polarizing films into a parallel transmission axis (parallel transmittance: Tp) and when the transmission axes of the two are orthogonal. The transmittance (orthogonal transmittance: Tc) is obtained by applying the following formula.

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

Each transmittance is expressed by the Y value of the visual acuity correction which has been performed by the 2 degree field of view (C light source) of JIS Z8701 by making 100% of the fully polarized light obtained by the polarizer of Gran Taylor.

<Next water resistance (warm water immersion test)>

By the same method as the examples and the comparative examples, polarizing films which have been respectively laminated with transparent protective films 1 and 3 as transparent protective films on both sides of the polarizer were prepared as samples. The polarizing film (sample) was cut into a rectangular shape in which the polarizer had an extension direction of 50 mm and a vertical direction of 25 mm. After immersing the polarizing film in warm water at 60°C for 6 hours, the length after peeling was visually measured with a magnifying glass. The measurement is the maximum value (mm) of the vertical distance of the cross-section from the part causing peeling.

<Next Water Resistance (Water Peeling Resistance)>

By the same method as the examples and comparative examples, a transparent protective film 1 and 3 have been laminated on both sides of the polarizer as a transparent protective thin film The polarized film of the film is made into a sample. The polarizing film (sample) was cut out to a size parallel to the extending direction of the polarizer of 200 mm and the straight direction of 20 mm. After immersing the polarizing film in pure water at 23°C for 24 hours, remove it from the pure water and wipe it off with a dry cloth, add a cut between the transparent protective film and the polarizer with a cutting knife, and apply the polarizing film Bonded to the glass plate. It takes less than 1 minute from taking out pure water to evaluation. Thereafter, the same evaluation as the aforementioned <adhesive force> is performed.

<Calculation of logPow>

The logPow value of each compound obtained by Chem Draw Ultra (manufactured by Cambridge Software Corporation) was used, and calculation was performed by the following formula. In addition, the polymerization initiator and photoacid generator will be deducted from the calculation.

LogPow=Σ(logPowi×Wi) of hardening adhesive

logPowi: the logPow value of each component of the hardening adhesive

Wi: (mole number of component i)/(total moles of each component of hardening adhesive)

)，logPow=5.12，日本化藥公司製。 In Table 1, the radically polymerizable compounds are shown as follows: HEAA: hydroxyethyl acrylamide, logPow=-0.56, homopolymer Tg=123°C, manufactured by Xingren Company; ACMO: acryloyl morpholine, logPow= -0.20, Tg of homopolymer=150℃, manufactured by Xingren Company; FA-THFM: tetrahydrofurfuryl (meth)acrylate, logPow=1.13, Tg of homopolymer=45℃, manufactured by Hitachi Chemical; LIGHT ACRYLATE DCP-A: Tricyclodecane dimethanol diacrylate, logPow=3.05, homopolymer Tg=134℃, manufactured by Kyoeisha Chemical Company; LIGHT ACRYLATE1,9ND-A: 1,9-nonanediol Diacrylate, logPow=3.68, homopolymer Tg=68℃, manufactured by Kyoeisha Chemical Company; ARONIX M-220: tripropylene glycol diacrylate, logPow=1.68, homopolymer Tg69℃, manufactured by East Asia Synthesis ; ARONIX M-306: neopentaerythritol tri/tetraacrylate, logPow=1.04, homopolymer Tg=250℃ or more, manufactured by East Asia Synthetic Corporation. Acrylic oligomer: ARUFON UP-1190, logPow=1.95 is made by East Asia Synthetic Corporation; compound containing alkoxy groups: NIKALAC MX-750LM, logPow=0.8 is made by Japan Carbide Industry Corporation; contains epoxy group Compound: JER828, logPow=4.76 is manufactured by Japan Epoxy Resin Co., Ltd.; isocyanate compound: KARENZ AOI, logPow=1.6 is manufactured by Showa Denko Corporation. The photopolymerization initiator shows: IRGACURE907 (2-methyl-1-(4-methylthiophenyl)-2-morpholinepropane-1-one), logPow=2.09, manufactured by BASF; KAYACURE DETX-s( Diethyl 9-oxosulfur

), logPow=5.12, manufactured by Nippon Kayaku.

The photoacid generator is CPI-100P (a 50% propylene carbonate solution containing triaryl hexafluoride phosphate as the main component), manufactured by Sanya Pro Company.

Claims (17)

A hardening type adhesive for polarizing film, which contains a hardening component, and the hardening type adhesive for polarizing film when the hardened product obtained by hardening the hardening type adhesive is immersed in pure water at 23°C for 24 hours Below, the overall water absorption rate represented by the following formula is 10% by weight or less, and the hardening type adhesive further contains an acrylic oligomer (A) formed by polymerizing (meth)acrylic monomers; the overall water absorption rate (%) ={(M2-M1)/M1}×100 In the above formula, M1 represents the weight of the hardened material before dipping, and M2 represents the weight of the hardened material after dipping. The hardening adhesive for polarizing film according to claim 1, wherein the octanol/water partition coefficient (logPow value) is 1 or more. The curable adhesive for polarizing films according to claim 1 or 2, wherein the curable component is an active energy ray curable component. The curable adhesive for polarizing film according to claim 3, wherein the active energy ray curable component contains a radical polymerizable compound. The hardening-type adhesive for polarizing films according to claim 4, wherein the radical polymerizable compound contains a (meth)acrylamide derivative. The hardening-type adhesive for polarizing films according to claim 4, wherein the radical polymerizable compound contains a polyfunctional compound, and the polyfunctional compound has at least two functional groups having radical polymerizable properties. The hardening-type adhesive for polarizing films according to claim 3 further contains a photopolymerization initiator. The hardening-type adhesive for polarizing films according to claim 3 further contains a photoacid generator (B). The hardening-type adhesive for polarizing films according to claim 3 further contains a compound (C) containing any of alkoxy groups and epoxy groups. The hardening-type adhesive for polarizing films according to claim 9, wherein the compound (C) containing any of alkoxy groups and epoxy groups is a compound (C1) containing alkoxy groups. The hardening type adhesive for polarizing films according to claim 10, wherein the aforementioned alkoxy-containing compound (C1) is an alkoxy-containing melamine compound. The hardening-type adhesive for polarizing films according to claim 3 further contains an isocyanate compound (D). The curable adhesive for polarizing films according to claim 1 or 2, wherein the curable component is a thermosetting component and further contains a thermal polymerization initiator. A polarizing film comprising a transparent protective film on at least one side of a polarizer with an adhesive layer interposed therebetween, and the adhesive layer is formed by a hardening type adhesive for polarizing film according to any one of claims 1 to 13. The hardened layer is formed. The polarizing film according to claim 14, wherein the thickness of the adhesive hardened layer is 0.1 to 3 μm. An optical film having at least one polarizing film as claimed in claim 14 or 15. An image display device using the polarizing film as in claim 14 or 15, or the optical film as in claim 16.