TW202140708A - Method for producing polarizing film - Google Patents

Abstract

A method for producing a polarizing film, said method comprising: a first coating step wherein a first wet coating film is formed by applying a highly adhesive composition that contains water and a hydrophilic monomer to a bonding surface of a polarizer; a second coating step wherein a second coating film is formed by applying an adhesive composition that contains a radically polymerizable compound and a cationically polymerizable compound to a bonding surface of a transparent protective film; a first thickness measurement step wherein the thickness of the first wet coating film is in-line measured; a drying step wherein a first dry coating film is formed by removing water from the first wet coating film with use of a dryer after the first thickness measurement step; a second thickness measurement step wherein the thickness of the first dry coating film is in-line measured after the drying step; and a dryness adjustment step wherein the dryness of a newly formed first dry coating film is adjusted by adjusting the temperature and/or the air flow rate of the dryer such that the ratio of the thickness of the first dry coating film to the thickness of the first wet coating film satisfies formula (A) below. (A): ((thickness of first dry coating film)/(thickness of first wet coating film)) - (water content in highly adhesive composition) ≤ 0.05.

Description

Manufacturing method of polarizing film

The present invention relates to a manufacturing method of a polarizing film. The polarizing film is provided with a transparent protective film through an adhesive layer on at least one side of a polarizer. The polarizing film can be used alone or in the form of a laminated optical film to form image display devices such as liquid crystal display devices (LCD), organic EL display devices, CRTs, and PDPs.

Liquid crystal display devices are rapidly expanding in the markets of clocks, mobile phones, PDAs, notebook computers, computer monitors, DVD players, and TVs. The liquid crystal display device visualizes the polarization state through the switching of the liquid crystal, and uses a polarizer based on its display principle. Especially in TV and other applications, the pursuit of high brightness, high contrast, and wide viewing angle is increasingly pursued, so that polarizing films are increasingly pursuing high transmittance, high polarization, and high color reproducibility.

As a polarizer, from the viewpoint of having high transmittance and high degree of polarization, for example, an iodine-based polarizer having a structure in which polyvinyl alcohol (hereinafter also referred to as "PVA") adsorbs and stretches iodine is the most widely used. Generally, a polarizing film is formed by laminating a transparent protective film on both sides of a polarizer by a so-called water-based adhesive, which is made by dissolving a polyvinyl alcohol-based material in water (Patent Document 1 below) ). The transparent protective film uses cellulose triacetate with high moisture permeability and the like. When the aforementioned water-based adhesive is used (so-called wet lamination), a drying step is required after bonding the polarizer and the transparent protective film.

On the other hand, an active energy ray curable adhesive has been proposed to replace the aforementioned water-based adhesive. When the active energy ray curable adhesive is used to manufacture the polarizing film, since the drying step is not required, the productivity of the polarizing film can be improved.

For example, Patent Document 2 proposes an active energy ray-curable adhesive composition that can bond a polyvinyl alcohol-based film and a plastic film simply and with sufficient strength; the active energy ray-curable adhesive composition contains (A) (Meth)acrylic radical polymerizable compound, (B) cationic polymerizable compound, (C) photoradical polymerization initiator, and (D) photocationic polymerization initiator. Prior art literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. 2001-296427 Patent Document 2: Japanese Patent No. 5046721

The problem to be solved by the invention In recent years, in the field of optical films such as polarizing films, the thinning and high-definition of displays continue to advance, and more stringent appearance quality is required. Under such circumstances, measures are required to suppress the generation of bubbles when bonding the polarizer and the protective film with an adhesive. As a countermeasure to suppress the generation of bubbles, it is effective to increase the coating thickness of the adhesive or reduce the viscosity of the adhesive. However, if the coating thickness of the adhesive is increased, there will be a problem of fading after humidification. Lowering the viscosity has the problem of increasing the limitation for satisfying the optical properties or adhesion.

In addition, as a means of lowering the viscosity of the adhesive, it is an effective means to mix water that is not a dangerous substance into the adhesive. However, in the case of a cationic polymerization type adhesive as described in Patent Document 2, water has the problem of hindering the cationic polymerization reaction.

The present invention solves the above-mentioned problems, and its object is to provide a continuous and stable method for manufacturing a polarizing film, the polarizer of the polarizing film and the transparent protective film have excellent adhesion to the adhesive layer, and the generation of bubbles has been suppressed.

Means to solve the problem The above-mentioned problem can be solved by the following configuration.

That is, the present invention relates to a manufacturing method of a polarizing film, the polarizing film is provided with a transparent protective film through the adhesive layer on at least one side of the polarizer, and the manufacturing method is characterized by including the following steps: The first coating step is to apply an easy-to-adhesive composition containing water and a hydrophilic monomer to the bonding surface of the polarizer while conveying the polarizer to form a wet first coating film; The second coating step is to apply an adhesive composition containing a radical polymerizable compound and a cation polymerizable compound to the bonding surface of the transparent protective film while conveying the transparent protective film to form a second coating film; The first thickness measurement step is to measure the thickness of the aforementioned wet first coating film online; The drying step is after the first thickness measurement step, using a dryer to remove the water in the wet first coating film to form a dry first coating film; The second thickness measurement step is to measure the thickness of the dry first coating film on-line after the drying step; The drying degree adjustment step is to adjust the temperature and temperature of the dryer so that the ratio of the thickness of the wet first coating film to the thickness of the dry first coating film obtained by the online measurement satisfies the following formula (A) / Or air volume, to adjust the degree of dryness of the newly formed dry first coating film; The bonding step is to bond the dry first coating film formed on the bonding surface of the polarizer and the second coating film formed on the bonding surface of the transparent protective film to form an uncured adhesive layer; and The next step is to bond the polarizer and the transparent protective film through the adhesive layer obtained by curing the uncured adhesive layer; (The thickness of the dry first coating film/the thickness of the wet first coating film)-(the water content in the easy-to-bond composition)≦0.05(A).

(惟，X為包含反應性基之官能基，R¹ 及R² 分別獨立表示氫原子、可具有取代基之脂肪族烴基、芳基或雜環基)。此外，本發明中，亦將前述通式(1)所示化合物稱為「含硼化合物」。In the manufacturing method of the above-mentioned polarizing film, the aforementioned easy-to-bond composition preferably contains the compound represented by the following general formula (1) and/or has an MO bond in the structural formula (M-based silicon, titanium, aluminum or zirconium, O-based oxygen atom)的organometallic compound; [Chemical formula 1]

(However, X is a functional group including a reactive group, and R ¹ and R ² each independently represent a hydrogen atom, an aliphatic hydrocarbon group that may have a substituent, an aryl group, or a heterocyclic group). In addition, in the present invention, the compound represented by the aforementioned general formula (1) is also referred to as a "boron-containing compound".

(惟，Y為有機基，X、R¹ 及R² 與前述相同)。In the above-mentioned method for producing a polarizing film, the compound represented by the aforementioned general formula (1) is preferably a compound represented by the following general formula (1'): [Chemical formula 2]

(However, Y is an organic group, and X, R ¹ and R ^{2 are the} same as above).

In the above-mentioned method for manufacturing a polarizing film, the reactive group of the compound represented by the general formula (1) is preferably selected from α, β-unsaturated carbonyl, vinyl, vinyl ether, epoxy, oxa At least one reactive group in the group consisting of cyclobutanyl group, amino group, aldehyde group, mercapto group and halogen group.

In the above-mentioned manufacturing method of the polarizing film, the moisture content of the polarizing member is preferably 15% by mass or less.

In the above-mentioned manufacturing method of the polarizing film, the first coating step and the second coating step are preferably coating steps of a post-use metering coating method.

In the above-mentioned manufacturing method of the polarizing film, the post-metering coating method is preferably a gravure roll coating method using a gravure roll.

Invention effect The manufacturing method of the polarizing film of the present invention is characterized in that water is mixed with the easy-to-bond composition to be applied to the bonding surface of the polarizer to reduce the viscosity to suppress the generation of bubbles. On the other hand, it is applied to the transparent The adhesive composition that protects the bonding surface of the film contains a radical polymerizable compound and a cation polymerizable compound in order to improve adhesiveness.

In the continuous production of polarizing films, when water remains in the first coating film obtained by applying the aforementioned easy-to-adhesive composition on the bonding surface of the polarizer, the first coating film is bonded and the aforementioned adhesive composition is applied. Water will remain in the uncured adhesive layer obtained from the second coating film. As a result, the uncured adhesive layer is hindered in the cationic polymerization reaction, resulting in a decrease in the adhesiveness of the adhesive layer. Therefore, the water in the first coating film must be removed in the drying step. In the drying step, the set temperature and set air volume of the dryer at the beginning are determined according to the amount of water blended in the easy-to-bond composition. We believe that by the drying conditions set at the beginning, the first coating The water will be sufficiently removed to the extent that it does not hinder the cationic polymerization reaction.

However, due to various factors such as deterioration and breakage of the drying equipment piping, blockage of the blower outlet, and temperature changes in the surrounding environment, the degree of drying of the first coating film varies in the continuous production of polarizing film. The water is not sufficiently removed, and water remains in the first coating film after the drying step. Therefore, as described above, the cationic polymerization reaction of the uncured adhesive layer is hindered by the remaining water, and it is difficult to stably form an adhesive layer with uniform adhesive characteristics, and it is difficult to continuously and stably manufacture an adhesive layer with excellent adhesiveness. The case of polarizing film.

According to the manufacturing method of the polarizing film of the present invention, the temperature and/or temperature of the dryer is adjusted so that the ratio of the thickness of the wet-type first coating film and the thickness of the dry-type first coating film obtained by online measurement meets the above-mentioned formula (A) The air volume is used to adjust the degree of dryness of the dry first coating film to be newly formed, thereby continuously and stably forming a dry first coating film with small variations in the degree of dryness and sufficient water removal. Therefore, it is possible to prevent the disadvantage that the cationic polymerization reaction of the uncured adhesive layer is hindered by the remaining water, and the adhesive layer with uniform adhesive properties can be formed continuously and stably.

According to the above, according to the manufacturing method of the polarizing film of the present invention, it is possible to continuously and stably manufacture a polarizing film with high appearance quality. The polarizing member of the polarizing film and the transparent protective film have excellent adhesion to the adhesive layer, and the generation of bubbles has been suppressed.

The aforementioned easy-to-bond composition preferably contains the aforementioned boron-containing compound. The aforementioned boron-containing compound can react with functional groups such as hydroxyl groups possessed by the polarizer. Thereby, the adhesion between the polarizer and the adhesive layer can be improved, and as a result, the effect of improving the water-resistant adhesion of the polarizing film can be exerted. Here, when the moisture content of the polarizer is low, for example, when the moisture content of the polarizer is 15% by mass or less, there are cases where the boron-containing compound and the functional group of the polarizer cannot sufficiently react and the effect cannot be sufficiently obtained. However, even when the moisture content of the polarizer is low, the easy-to-bond composition contains water, so the reactivity of the boron-containing compound with the functional group of the polarizer will increase, thereby improving the polarizer and the adhesive Adherence of layers. As a result, even when the moisture content of the polarizer is low, it can still achieve the improvement of the water resistance of the polarizing film, the improvement of the coating properties of the easy-to-bond composition, and the suppression of bubbles in the polarizing film.

The aforementioned easy-bonding composition preferably contains the aforementioned organometallic compound. The aforementioned organometallic compound becomes an active metal species due to the inclusion of moisture, and as a result, the organometallic compound forms a strong bond with the polarizer. However, the aforementioned organometallic compound has multiple reaction points, so the organometallic compound that has reacted with the polarizer still has unreacted points. The aforementioned organometallic compound can form a strong bond with the curable component in the second coating film formed on the bonding surface of the transparent protective film. As mentioned above, the aforementioned organometallic compound can form a strong bond with both the polarizer and the adhesive layer, so the water resistance between the polarizer and the adhesive layer will be greatly improved.

The aforementioned first coating step and the aforementioned second coating step are preferably coating steps using a post-metering coating method. Thereby, the adhesiveness of the polarizing film can be improved, and at the same time, the coating properties of the easy-to-adhesive composition and the adhesive composition can be improved, and the thickness uniformity of the first coating film and the second coating film can be improved. In addition, the "post-metering coating method" in the present invention refers to a method in which an external force is applied to a liquid film to remove excess liquid to obtain a predetermined coating film thickness. Specific examples of the post-metering coating method include a gravure roll coating method, a forward roll coating method, an air knife coating method, and a rod/rod coating method.

The present invention is a manufacturing method of a polarizing film. The polarizing film is provided with a transparent protective film through an adhesive layer on at least one side of a polarizer. The manufacturing method includes the following steps: The first coating step is to apply an easy-to-adhesive composition containing water and a hydrophilic monomer to the bonding surface of the polarizer while conveying the polarizer to form a wet first coating film; The second coating step is to apply an adhesive composition containing a radical polymerizable compound and a cation polymerizable compound to the bonding surface of the transparent protective film while conveying the transparent protective film to form a second coating film; The first thickness measurement step is to measure the thickness of the aforementioned wet first coating film online; The drying step is after the first thickness measurement step, using a dryer to remove the water in the wet first coating film to form a dry first coating film; The second thickness measurement step is to measure the thickness of the dry first coating film on-line after the drying step; The drying degree adjustment step is to adjust the temperature and temperature of the dryer so that the ratio of the thickness of the wet first coating film to the thickness of the dry first coating film obtained by the online measurement satisfies the following formula (A) / Or air volume, to adjust the degree of dryness of the newly formed dry first coating film; The bonding step is to bond the dry first coating film formed on the bonding surface of the polarizer and the second coating film formed on the bonding surface of the transparent protective film to form an uncured adhesive layer; and The next step is to bond the polarizer and the transparent protective film through the adhesive layer obtained by curing the uncured adhesive layer. (The thickness of the dry first coating film/the thickness of the wet first coating film)-(the water content in the easy-to-bond composition)≦0.05(A)

Hereinafter, the manufacturing method of the polarizing film of the present invention will be described in detail.

＜Easy bonding composition＞ The easy-to-bond composition contains at least water and a hydrophilic monomer.

The hydrophilic monomer is not particularly limited as long as it is a monomer that is soluble in water. Examples include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, citraconic acid, and monobutylhydroxyfumaric acid. Carboxyl group-containing monomers such as esters and monobutylhydroxyiconate and their salts; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-(meth)acrylic acid Hydroxyl-containing monomers such as hydroxybutyl ester, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate and polyethylene glycol mono(meth)acrylate; (meth)propylene Acrylamine monomers such as amide, diacetone acrylamide, and N-methylol (meth)acrylamide; N-acryloyl mopholin, N-acryloyl piperidine, N-methyl Heterocyclic-containing (meth)acrylamide derivatives such as acrylpiperidine and N-acrylonitrile pyrrolidine; diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylic acid Both end ester compounds of ethylene glycol oligomers such as esters and polyethylene glycol di(meth)acrylate; both end ester compounds of propylene glycol oligomers, etc. These may use 1 type, and may use 2 or more types together. Among these, hydroxyl-containing monomers are preferably used.

The content of the hydrophilic monomer in the easy-to-bond composition is not particularly limited. From the viewpoint of improving adhesion, it is preferably 20% by mass or more, more preferably 40% by mass or more, and preferably 80% by mass or less, more preferably It is 65% by mass or less.

The easy bonding composition may contain a polymerizable compound X having an SP value of 21.0 (MJ/m ³ ) ^1/2 or more and 26.0 (MJ/m ³ ) ^1/2 or less as a curable component.

As long as the polymerizable compound X is a compound having a radical polymerizable group such as a (meth)acrylate group and having an SP value of 21.0 (MJ/m ³ ) ^1/2 or more and 26.0 (MJ/m ³ ) ^1/2 or less, Can be used indefinitely. Examples of the polymerizable compound X include N-methoxymethacrylamide (SP value 22.9), N-ethoxymethacrylamide (SP value 22.3), and the like. In addition, the polymerizable compound X can also be suitably used commercially available products. Examples include WASMER 2MA (manufactured by Kasano Kosan Co., Ltd., SP value 22.9), WASMER EMA (manufactured by Kasano Kosan Co., Ltd., SP value 22.3), and WASMER 3MA (Kasano Kosan Co., Ltd., SP value 22.3). Production company system, SP value 22.4) and so on. These may use 1 type, and may use 2 or more types together.

Here, the calculation method of the SP value (solubility parameter) of the present invention is described below.

(惟，Δei係源自原子或基團之在25℃下之蒸發能，Δvi係在25℃下之莫耳體積)。(Calculation method of solubility parameter (SP value)) In the present invention, the solubility parameter (SP value) of polymerizable compound X can be calculated by Fedors [refer to "Polymer Engineering and Science (Polymer Eng. &Sci.)", Volume 14, No. 2 (1974), pages 148~154] calculated and calculated, namely: [Math 1]

(However, Δei is derived from the evaporation energy of the atom or group at 25°C, and Δvi is the molar volume at 25°C).

The Δei and Δvi in the above-mentioned mathematical formula show the fixed value that gives the i atoms and groups in the main molecule a fixed value. The representative examples of the values of Δe and Δv assigned to atoms or groups are shown in Table 1 below.

[Table 1]

The content of the polymerizable compound X in the easy-to-bond composition is not particularly limited, but is preferably 0.5% by mass or less.

(惟，X為包含反應性基之官能基，R¹ 及R² 分別獨立表示氫原子、可具有取代基之脂肪族烴基、芳基或雜環基)。前述脂肪族烴基可舉碳數1~20之可具有取代基之直鏈或支鏈烷基、碳數3~20之可具有取代基之環狀烷基、碳數2~20之烯基；芳基可舉碳數6~20之可具有取代基之苯基、碳數10~20之可具有取代基之萘基等；雜環基可舉例如包含至少一個雜原子且可具有取代基之5員環或6員環的基團。該等可相互連結形成環。通式(1)中，作為R¹ 及R² 以氫原子、碳數1~3之直鏈或支鏈烷基為佳，且氫原子最佳。此外，通式(1)所示化合物可在最終形成之接著劑層中以未反應之狀態存在，亦可以各官能基已反應之狀態存在。In addition, the easy-to-bond composition preferably contains a compound represented by the following general formula (1): [Chemical formula 3]

(However, X is a functional group including a reactive group, and R ¹ and R ² each independently represent a hydrogen atom, an aliphatic hydrocarbon group that may have a substituent, an aryl group, or a heterocyclic group). The aforementioned aliphatic hydrocarbon group may include a linear or branched alkyl group having 1 to 20 carbon atoms, which may have substituents, a cyclic alkyl group having 3 to 20 carbon atoms, which may have substituents, and alkenyl groups having 2 to 20 carbon atoms; The aryl group may include a phenyl group having 6 to 20 carbon atoms, which may have a substituent, and a naphthyl group having 10 to 20 carbon atoms, which may have a substituent; 5-membered ring or 6-membered ring group. These can be connected to each other to form a ring. In the general formula (1), as R ¹ and R ^2, a hydrogen atom, a linear or branched alkyl group having 1 to 3 carbon atoms is preferred, and a hydrogen atom is most preferred. In addition, the compound represented by the general formula (1) may exist in an unreacted state in the finally formed adhesive layer, or may exist in a state in which each functional group has reacted.

The X of the compound represented by the general formula (1) is a functional group that contains a reactive group and can react with the curable component constituting the adhesive layer. The reactive group contained in X includes, for example, a hydroxyl group, an amino group, an aldehyde group, Carboxyl, vinyl, (meth)acrylic, styryl, (meth)acrylic, vinyl ether, epoxy, oxetanyl, α,β-unsaturated carbonyl, Mercapto, halogen, etc. When the adhesive composition constituting the adhesive layer is curable with active energy rays, the reactive group contained in X is preferably selected from vinyl, (meth)acrylic, styryl, and (meth)acrylic groups. At least one reactive group in the group consisting of an amide group, a vinyl ether group, an epoxy group, an oxetanyl group, and a mercapto group; in particular, the adhesive composition of the present invention constituting the adhesive layer is a free radical Polymerization, so the reactive group contained in X is preferably at least one reactive group selected from the group consisting of (meth)acrylic acid groups, styryl groups, and (meth)acrylic acid amino groups; When the compound represented by the general formula (1) has a (meth)acrylamido group, since it has high reactivity, the copolymerization rate with the active energy ray adhesive composition can be increased, which is preferable. In addition, the (meth)acrylamide group has high polarity and excellent adhesiveness, so the effect of the present invention can be efficiently obtained, which is also suitable from this point of view. In addition, the adhesive composition of the present invention constituting the adhesive layer is cationic polymerizable, so the reactive group contained in X preferably has a group selected from the group consisting of hydroxyl, amino, aldehyde, carboxyl, vinyl ether, epoxy, and oxygen. At least one functional group among the heterocyclobutane group and the mercapto group, especially when it has an epoxy group, is preferred because the adhesive layer obtained has excellent adhesion to the adherend; when it has a vinyl ether group, it is The adhesive composition is excellent in curability, so it is preferred.

(惟，Y為有機基，X、R¹ 及R² 與前述相同)。更佳可舉以下化合物(1a)~(1d)。Preferred specific examples of the compound represented by the general formula (1) include the compound represented by the following general formula (1'): [Chemical formula 4]

(However, Y is an organic group, and X, R ¹ and R ^{2 are the} same as above). More preferable examples include the following compounds (1a) to (1d).

[Chemical formula 5]

In the present invention, the compound represented by the general formula (1) may be a reactive group directly bonded to the boron atom. As shown in the foregoing specific examples, the compound represented by the general formula (1) is preferably separated from the reactive group and the boron atom. Those with organic bonds are compounds represented by the general formula (1'). When the compound represented by the general formula (1) is bonded to a reactive group via an oxygen atom bonded to a boron atom, the water adhesion resistance of the polarizing film tends to deteriorate. On the other hand, when the compound represented by the general formula (1) does not have a boron-oxygen bond, but has a boron-carbon bond by bonding a boron atom to an organic group and contains a reactive group (general formula ( 1')), since it can improve the water adhesion resistance of the polarizing film, it is preferred. The aforementioned organic group specifically means an organic group with 1 to 20 carbons that may have a substituent, and more specifically includes, for example, a linear or branched alkylene group having 1 to 20 carbons and may have a substituent, and a carbon number of 3 to Cyclic alkylene group of 20 which may have substituents, phenylene group of which may have substituents of carbon number of 6 to 20, and naphthylene group of which may have substituents of carbon number of 10 to 20, etc.

The compound represented by the general formula (1) can exemplify the ester of hydroxyethyl acrylamide and boric acid, the ester of hydroxymethacrylamide and boric acid, the ester of hydroxyethyl acrylate and boric acid, and Esters of (meth)acrylate and boric acid such as hydroxybutyl acrylate and boric acid.

In the easy bonding composition, if the content of the compound represented by the general formula (1) is too small, the ratio of the compound represented by the general formula (1) existing at the interface between the polarizing member and the adhesive layer will decrease, and the easy bonding effect may be reduced situation. Therefore, in the easy-to-bond composition, the content of the compound represented by the general formula (1) is preferably 0.01% by mass or more, preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and particularly preferably 0.5% by mass or more. Moreover, in the easy-to-bond composition, the content of the compound represented by the general formula (1) is usually 5% by mass or less, preferably 3% by mass or less, and preferably 2% by mass or less.

In addition, the easy-to-bond composition preferably contains an organometallic compound having an M-O bond (M-based silicon, titanium, aluminum or zirconium, and O-based oxygen atoms) in the structural formula. In addition, the aforementioned organometallic compound may exist in an unreacted state in the finally formed adhesive layer, or may exist in a state in which each functional group has reacted.

The aforementioned organometallic compound has an M-O bond (M-type silicon, titanium, aluminum or zirconium, O-type oxygen atom) in the structural formula. The aforementioned organometal is preferably at least one selected from the group consisting of organosilicon compounds, metal alkoxides, and metal chelate compounds.

The aforementioned organosilicon compound can be used without particular limitation to have Si-O bonds, and specific examples include active energy ray curable organosilicon compounds or non-active energy ray curable organosilicon compounds. In particular, it is preferable that the carbon number of the organic group contained in the organosilicon compound is 3 or more. Specific examples of active energy ray-curable compounds include: vinyl trichlorosilane, vinyl trimethoxy silane, vinyl triethoxy silane, 2-(3,4 epoxycyclohexyl) ethyl trimethoxy Silane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-benzene Vinyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyl Methyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, etc.

Preferred are 3-methacryloxypropyl trimethoxysilane and 3-acryloxypropyl trimethoxysilane.

Compounds that are not curable with active energy rays are preferably compounds with amine groups. Specific examples of the compound having an amine group include: γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, γ-aminopropylmethyl Dimethoxysilane, γ-aminopropylmethyl diethoxysilane, γ-(2-aminoethyl)aminopropyl trimethoxysilane, γ-(2-aminoethyl)aminopropylmethyl Dimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropylmethyl diethoxysilane, γ-(2- Aminoethyl)aminopropyltriisopropoxysilane, γ-(2-(2-aminoethyl)aminoethyl)aminopropyltrimethoxysilane, γ-(6-aminohexyl)aminopropyltrimethyl Oxysilane, 3-(N-ethylamino)-2-methylpropyltrimethoxysilane, γ-ureapropyltrimethoxysilane, γ-ureapropyltriethoxysilane, N-phenyl -γ-Aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl-γ-aminopropyltriethoxysilane, N-cyclohexylaminomethyl Triethoxysilane, N-cyclohexylaminomethyldiethoxymethylsilane, N-phenylaminomethyltrimethoxysilane, (2-aminoethyl)aminomethyltrimethoxysilane, N ,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine and other amino-containing silanes; N-(1,3-dimethylbutylene)-3-(triethoxy (Silyl)-1-propylamine and other ketimine silanes.

The compound having an amine group may be used alone or in combination of plural kinds. Among them, 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-propylamine is preferred.

Specific examples of non-active energy ray-curable compounds other than the above include: 3-ureapropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane , 3-Mercaptopropyl trimethoxysilane, bis(triethoxysilylpropyl) tetrasulfide, 3-isocyanate propyltriethoxysilane, imidazole silane, etc.

The aforementioned metal alkoxide is a compound in which at least one alkoxy group that is an organic group is bonded to a metal, and a metal chelate is a compound in which an organic group is bonded or coordinated to a metal via an oxygen atom. The metal is preferably titanium, aluminum, or zirconium. Among them, compared to titanium, aluminum and zirconium have faster reactivity, and the useful life of the adhesive composition may be shortened and the effect of improving the water resistance of the adhesive composition may be lower. Therefore, from the viewpoint of improving the water resistance of the adhesive layer, the metal of the organometallic compound is preferably titanium.

When the easy-to-bond composition contains a metal alkoxide as the organometallic compound, it is preferable to use a carbon number of the organic group possessed by the metal alkoxide of 3 or more, and it is more preferable to contain 6 or more. If the carbon number is 2 or less, the useful life of the easy-to-bond composition may be shortened and the effect of improving the water-resistant adhesiveness may be lowered. The organic group having a carbon number of 6 or more includes, for example, an octyloxy group, which can be suitably used. Suitable metal alkoxides can include, for example: tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer, tetraoctyl titanate, tertiary amyl titanate, tertiary titanate tertiary Butyl ester, tetrastearyl titanate, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, zirconium tetraoctoxide, zirconium tetra- and tertiary butoxide, zirconium tetra-propoxide, aluminum secondary butoxide, aluminum ethoxide, isopropyl Aluminum alkoxide, aluminum butoxide, single secondary butoxide aluminum diisopropoxide, single secondary butoxy aluminum diisopropoxide, etc. Among them, tetraoctyl titanate is preferred.

When the easy-to-bond composition contains a metal chelate as the organometallic compound, it preferably contains an organic group of the metal chelate with 3 or more carbon atoms. If the carbon number is 2 or less, the useful life of the easy-to-bond composition may be shortened, and the effect of improving the water resistance of the polarizing film may decrease. The organic group having a carbon number of 3 or more includes, for example, acetacetone group, ethylacetate group, isostearate group, and caprylyl ester group. Among them, from the viewpoint of improving the water resistance of the adhesive layer, the organic group is preferably acetacetone group or ethylacetate group. Suitable metal chelate compounds may include, for example: titanium acetone acetonate, titanium caprylate, titanium tetraacetone acetonate, titanium acetoacetate, titanium polyhydroxystearate, dipropoxy bis(acetone acetone) ) Titanium, dibutoxy bis (octanediol acid) titanium, dipropoxy bis (ethyl acetate) titanium, titanium lactate, titanium diethanolamine, titanium triethanolamine, titanium dipropoxy bis (lactate) , Dipropoxy bis(triethanolamine) titanium, di-n-butoxy bis(triethanolamine) titanium, tri-n-butoxy titanium monostearate, diisopropoxy bis(ethyl acetate) titanium, Diisopropoxy bis (acetate) titanium, diisopropoxy bis (acetone) titanium, titanium phosphate compound, titanium ammonium lactate, 1,3-propane dioxy bis (acetate) Ethyl) titanium, titanium dodecylbenzenesulfonate compound, amine ethylamine titanium ethoxide, zirconium tetraacetone acetone, zirconium acetone monoacetone, zirconium diacetone acetone, double acetone acetone (ethyl acetone) Zirconium, zirconium acetate, tri-n-butoxy (ethyl acetate) zirconium, di-n-butoxy bis (ethyl acetate) zirconium, n-butoxy ginseng (ethyl acetate) zirconium, four ( Acetate n-propyl acetate) zirconium, Si (acetate ethyl acetate) zirconium, Si (acetate ethyl acetate) zirconium, (acetate ethyl acetate) aluminum, acetone acetone aluminum, acetone acetone bis(ethyl acetone) Ethyl Acetate) Aluminum, Diisopropoxy (Ethyl Acetate) Aluminum, Diisopropoxy (Ethyl Acetate) Aluminum, Isopropoxy Bis(Ethyl Acetate) Aluminum, Isopropoxy Base bis (acetone acetone) aluminum, ginseng (acetate ethyl acetate) aluminum, ginseng (acetone acetone) aluminum, mono acetyl acetone bis (acetate ethyl acetate) aluminum. Among them, titanium acetylacetone and titanium acetacetone are preferred.

The organometallic compounds that can be used in the present invention include zinc octoate, zinc laurate, zinc stearate, tin octoate and other organic carbonate metal salts, acetone tin chelate, and benzyl acetone zinc chelate. , Zinc chelate compounds such as dibenzyl methane zinc chelate, ethyl acetate zinc chelate, etc.

If the content of the organometallic compound in the easy-to-bond composition is too small, the ratio of the organometallic compound existing at the interface between the polarizer and the adhesive layer will decrease, and the easy-to-bond effect may be reduced. Therefore, the content of the organometallic compound in the easy-to-bond composition is preferably 0.01% by mass or more, preferably 0.05% by mass or more, and more preferably 0.1% by mass or more. In addition, the content of the organometallic compound in the easy-to-bond composition is usually 10% by mass or less.

The easy-to-bond composition contains water as a solvent. It is also possible to mix organic solvents in the easy-to-bond composition within the range that does not impair the effects of the present invention, but it is better not to mix organic solvents.

The easy-to-bond composition may also contain additives.

The aforementioned additives include, for example, binder resins, surfactants, plasticizers, tackifiers, low molecular weight polymers, polymerizable monomers, surface lubricants, leveling agents, antioxidants, preservatives, light stabilizers, ultraviolet rays Absorbent, polymerization inhibitor, silane coupling agent, titanate coupling agent, inorganic or organic filler, metal powder, granular, foil, etc.

＜Adhesive composition＞ The adhesive composition of the present invention may be thermally curable or active energy ray curable. The resin constituting the thermosetting adhesive composition can include polyvinyl alcohol resin, epoxy resin, unsaturated polyester, urethane resin, acrylic resin, urea resin, melamine resin, phenol resin, etc., and can be used in combination as needed. Agent to use. As the resin constituting the thermosetting adhesive composition, polyvinyl alcohol resin and epoxy resin can be more suitably used. Active energy ray curable adhesive compositions are classified by active energy rays, and can be roughly classified into electron beam curability, ultraviolet curability, and visible light curability. In addition, the curing reaction is used to classify the radical polymerizable adhesive composition and the cationic polymerizable adhesive composition. In the present invention, a radical polymerizable and cationically polymerizable adhesive composition is used. In addition, in the present invention, the active energy rays with a wavelength range of 10 nm and less than 380 nm are labeled as ultraviolet rays, and the active energy rays with a wavelength range of 380 nm to 800 nm are labeled as visible rays.

In the manufacturing method of the polarizing film of the present invention, the adhesive composition is preferably curable with active energy rays. In addition, the visible ray hardenability using visible rays of 380nm~450nm is particularly good.

The adhesive composition of the present invention contains at least a radical polymerizable compound and a cation polymerizable compound.

Examples of the radically polymerizable compound include compounds having a radically polymerizable functional group having carbon-carbon double bonds such as a (meth)acryloyl group and a vinyl group. Either a monofunctional radical polymerizable compound or a multifunctional radical polymerizable compound having two or more functions can be used. In addition, these radically polymerizable compounds may be used alone or in combination of two or more kinds. These radically polymerizable compounds are preferably compounds having a (meth)acryloyl group, for example. In addition, in the present invention, the term "(meth)acryl" refers to an acrylic group and/or a methacryl group, and "(meth)" is synonymous below.

(惟，R³ 為氫原子或甲基，R⁴ 及R⁵ 分別獨立為氫原子、烷基、羥烷基、烷氧基烷基或環狀醚基，且R⁴ 及R⁵ 亦可形成環狀雜環)。烷基、羥烷基及/或烷氧基烷基之烷基部分的碳數無特別限定，可舉例如1~4個者。此外，R⁴ 及R⁵ 亦可形成之環狀雜環可舉例如N-丙烯醯基嗎福林等。Examples of monofunctional radical polymerizable compounds include compounds represented by the following general formula (2): [Chemical formula 6]

(However, R ³ is a hydrogen atom or a methyl group, R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a cyclic ether group, and R ⁴ and R ⁵ can also form Cyclic heterocycle). The carbon number of the alkyl part of an alkyl group, a hydroxyalkyl group, and/or an alkoxyalkyl group is not specifically limited, For example, 1 to 4 can be mentioned. In addition, R ⁴ and R ⁵ may also form a cyclic heterocyclic ring, for example, N-propenyl mopholine and the like.

Specific examples of the compound represented by the general formula (2) 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. containing N-alkyl ( (Meth)acrylamide derivatives; N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-hydroxymethyl-N-propane (meth)acrylamide N-hydroxyalkyl-containing (meth)acrylamide derivatives such as amines; N-methoxymethacrylamide, N-ethoxymethacrylamide, and other N-alkoxy-containing (meth)acrylamide Group) acrylamide derivatives and the like. In addition, the (meth)acrylamide derivative containing a cyclic ether group may include a heterocyclic ring-containing (meth)acrylamide derivative in which the nitrogen atom of the (meth)acrylamide group forms a heterocyclic ring, and may For example, N-acryloyl mopholin, N-acryloyl piperidine, N-methacryloyl piperidine, N-acryloyl pyrrolidine, and the like are listed.

In addition, the adhesive composition may contain a monofunctional radical polymerizable compound other than the above as a curable component. Examples of the monofunctional radical polymerizable compound include various (meth)acrylic acid derivatives having a (meth)acryloyloxy group. Examples of the aforementioned (meth)acrylic acid derivatives include: 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, secondary butyl (meth)acrylate, tertiary butyl (meth)acrylate Ester, n-pentyl (meth)acrylate, tertiary pentyl (meth)acrylate, 3-pentyl (meth)acrylate, 2,2-dimethylbutyl (meth)acrylate, (methyl) ) N-hexyl acrylate, cetyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-2-propylpentyl (meth) (Meth)acrylic acid (carbon number 1-20) alkyl esters such as acrylate and n-octadecyl (meth)acrylate.

In addition, the aforementioned (meth)acrylic acid derivatives include, for example, cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate and other cycloalkyl (meth)acrylates; benzyl (meth)acrylate and the like (meth) Yl) aralkyl acrylate; 2-isobornyl (meth)acrylate, 2-norbornyl methyl (meth)acrylate, 5-norbornen-2-yl-methyl (meth)acrylate, ( 3-Methyl-2-norbornyl methyl acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentyl (meth)acrylate Polycyclic (meth)acrylates such as esters; 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxymethyl (meth)acrylate Oxyethyl, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxyethyl (meth)acrylate, alkylphenoxypolyethylene glycol ( Alkoxy or phenoxy-containing (meth)acrylates such as meth)acrylates and the like. Among them, dicyclopentenoxyethyl acrylate and phenoxyethyl acrylate are preferable in view of good adhesion to various protective films.

In addition, examples of the aforementioned (meth)acrylic acid derivatives include: 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, (meth)acrylic acid Base) 2-hydroxybutyl acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxy(meth)acrylate Hydroxyalkyl (meth)acrylates such as decyl ester, 12-hydroxylauryl (meth)acrylate, etc.; or [4-(hydroxymethyl)cyclohexyl]methyl acrylate, cyclohexanedimethanol mono(methyl) Acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate and other hydroxyl-containing (meth)acrylates; glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate Epoxy-containing (meth)acrylates such as glycidyl ether; 2,2,2-trifluoroethyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate Ester, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropentyl (meth)acrylate, heptafluorodecyl (meth)acrylate, 3- Halogen-containing (meth)acrylates such as chloro-2-hydroxypropyl ester; (meth)acrylic acid alkylaminoalkyl esters such as dimethylaminoethyl (meth)acrylate; (meth)acrylic acid 3 -Methyl oxetanyl, 3-methoxy-oxetanyl methyl (meth)acrylate, 3-eth-oxetanyl methyl (meth)acrylate, (methyl) (Meth) acrylates containing oxetanyl groups such as 3-but-oxetanyl methyl acrylate and 3-hex-oxetanyl methyl (meth)acrylate; (methyl) ) (Meth)acrylates with heterocycles such as tetrahydrofurfuryl acrylate, butyrolactone (meth)acrylate, etc.; or neopentyl glycol (meth)acrylic acid adduct of hydroxytrimethylacetate, (meth) Acrylic acid p-phenylphenol ester and so on. Among them, 2-hydroxy-3-phenoxypropyl acrylate is preferable because it has excellent adhesion to various protective films.

In addition, the monofunctional radical polymerizable compound includes: (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, iso Carboxyl group-containing monomers such as crotonic acid and ω-carboxy-polycaprolactone mono(meth)acrylate.

In addition, examples of the monofunctional radical polymerizable compound include internal amine-based vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactone, and methyl vinylpyrrolidone; ethylene Vinyl pyridine, vinyl piperidone, vinyl pyrimidine, vinyl piperidine, vinyl pyridine, vinyl pyrrole, vinyl imidazole, vinyl azole, vinyl mopholin and other vinyl groups with nitrogen-containing heterocycles Department of monomers and so on.

In the adhesive composition of the present invention, if the monofunctional radical polymerizable compound contains a hydroxyl group-containing (meth)acrylate, a carboxyl group-containing (meth)acrylate or a phosphoric acid group-containing (methyl) ) Acrylic, etc., the adhesion to various substrates will be improved. The content of the hydroxyl-containing (meth)acrylate is preferably 1% by mass to 30% by mass relative to the adhesive composition. When the content of the hydroxyl-containing (meth)acrylate is too much, the water absorption rate of the hardened product may increase and the water resistance may deteriorate. The content of the carboxyl group-containing (meth)acrylate is preferably 1% by mass to 20% by mass relative to the adhesive composition. When the content of the carboxyl group-containing (meth)acrylate is too much, the optical durability of the polarizing film will decrease, which is not good. The phosphoric acid group-containing (meth)acrylate includes, for example, 2-(meth)acryloyloxyethyl acid phosphate; the content thereof is preferably 0.1% by mass to 10% by mass relative to the adhesive composition. When the content of the phosphoric acid group-containing (meth)acrylate is too much, the optical durability of the polarizing film will decrease, which is not good.

In addition, as the monofunctional radically polymerizable compound, a radically polymerizable compound having an active methylene group can be used. The radically 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 in the molecule, and having an active methylene group. Examples of the active methylene group include acetylacetoxy, alkoxypropanedioxin, cyanoacetoxy, and the like. The aforementioned active methylene group is preferably acetyl acetyl group. Examples of radically polymerizable compounds with active methylene groups include: 2-acetylacetoxyethyl (meth)acrylate, 2-acetylacetoxypropyl (meth)acrylate, 2 -Acetylacetoxy-1-methylethyl(meth)acrylate and other Acetylacetoxyalkyl(meth)acrylates; 2-ethoxypropanedioxyloxyethyl (meth) Yl)acrylate, 2-cyanoacetoxyethyl (meth)acrylate, N-(2-cyanoacetoxyethyl)acrylamide, N-(2-propionylacetate (Oxybutyl)acrylamide, N-(4-acetylacetoxymethylbenzyl)acrylamide, N-(2-acetylacetoxyaminoethyl)acrylamide, and the like. The radically polymerizable compound having a reactive methylene group is preferably acetoxyalkyl (meth)acrylate.

In addition, polyfunctional radical polymerizable compounds having two or more functions include, for example, N,N'-methylenebis(meth)acrylamide and tripropylene glycol di(meth)acrylamide derivatives which are polyfunctional (meth)acrylamide derivatives 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)acrylate, bisphenol A di(meth)acrylate, bisphenol A ethylene oxide adduct bis(methyl) Base) acrylate, bisphenol A propylene oxide adduct di(meth)acrylate, bisphenol A diglycidyl ether di(meth)acrylate, neopentyl glycol di(meth)acrylate , Tricyclodecane dimethanol di(meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, dioxanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate Base) acrylate, neopentaerythritol tri(meth)acrylate, neopentaerythritol tetra(meth)acrylate, dineopentaerythritol penta(meth)acrylate, dineopentaerythritol hexa(meth)acrylate (Meth)acrylic acid esters with polyhydric alcohols such as diglycerol tetra(meth)acrylate modified by EO, 9,9-bis[4-(2-(meth)acryloyloxyethyl) (Oxy)phenyl]茀. Specific examples are ARONIX M-220 (manufactured by Toagosei Co., Ltd.), LIGHT-ACRYLATE 1,9ND-A (manufactured by Kyoeisha Chemical Co., Ltd.), LIGHT-ACRYLATE DGE-4A (manufactured by Kyoeisha Chemical Co., Ltd.), and LIGHT-ACRYLATE DCP -A (manufactured by Kyoeisha Chemical Co., Ltd.), SR-531 (manufactured by Sartomer Co., Ltd.), CD-536 (manufactured by Sartomer Co., Ltd.), etc. are preferred. In addition, according to needs, for example, various epoxy (meth)acrylates, urethane (meth)acrylates, polyester (meth)acrylates, or various (meth)acrylate monomers, etc. . In addition, the polyfunctional (meth)acrylamide derivative has high polymerization speed and excellent productivity, and has excellent crosslinkability when the adhesive composition is made into a cured product, so it is preferably contained in the adhesive composition.

From the viewpoint of compatibility with polarizers or various transparent protective films, and optical durability in harsh environments, the radical polymerizable compound is used in combination with a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound Better. In addition, the liquid viscosity of the monofunctional radical polymerizable compound is relatively low, so by containing it in the adhesive composition, the liquid viscosity of the adhesive composition can be reduced. In addition, most of the monofunctional radical polymerizable compounds have functional groups capable of expressing various functions. By including them in the adhesive composition, the adhesive composition and/or the cured product of the adhesive composition can exhibit various functions. . Since the polyfunctional radical polymerizable compound can cause three-dimensional crosslinking of the cured product of the adhesive composition, it is preferably contained in the adhesive composition. The polyfunctional radical polymerizable compound is preferably used in 10 to 1000 parts by mass relative to 100 parts by mass of the monofunctional radical polymerizable compound.

The content of the radical polymerizable compound in the adhesive composition is preferably 55 to 80% by mass, more preferably 65 to 80% by mass, and more preferably 67 to 75% by mass from the viewpoint of improving the adhesion of the adhesive layer %.

When electron beams are used for active energy rays, the adhesive composition does not have to contain a photo-radical polymerization initiator. When ultraviolet or visible rays are used for active energy rays, the adhesive composition preferably contains light free radicals. Base polymerization initiator.

、2-氯9-氧硫𠮿

、2-甲基9-氧硫𠮿

、2,4-二甲基9-氧硫𠮿

、異丙基-9-氧硫𠮿

、2,4-二氯9-氧硫𠮿

、2,4-二乙基9-氧硫𠮿

、2,4-二異丙基9-氧硫𠮿

、十二基9-氧硫𠮿

等的9-氧硫𠮿

系化合物；樟腦醌；鹵化酮；醯基氧化膦；醯基膦酸酯等。The photoradical polymerization initiator can be appropriately selected according to the active energy rays. When curing by ultraviolet or visible light, a photo-radical polymerization initiator that cracks by ultraviolet or visible light is used. Examples of photoradical polymerization initiators include benzil, diphenyl ketone, benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone And other benzophenone compounds; 4-(2-hydroxyethoxy) phenyl(2-hydroxy-2-propyl) ketone, α-hydroxy-α,α'-dimethylacetophenone, 2- Aromatic ketone compounds such as methyl-2-hydroxypropiophenone and α-hydroxycyclohexylphenylketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2- Acetophenone compounds such as diethoxyacetophenone and 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinyl-1; benzoin methyl ether , Benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, anisin methyl ether and other benzoin alkyl ether compounds; benzyl dimethyl ketal and other aromatics Ketal compounds; aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime ; 9-oxysulfur 𠮿

, 2-Chloro 9-oxysulfur 𠮿

, 2-Methyl 9-oxysulfur 𠮿

, 2,4-Dimethyl 9-oxysulfur 𠮿

, Isopropyl-9-oxysulfur 𠮿

, 2,4-Dichloro 9-oxysulfur 𠮿

, 2,4-Diethyl 9-oxysulfur 𠮿

, 2,4-Diisopropyl 9-oxysulfur 𠮿

, Dodecyl 9-oxysulfur 𠮿

Waiting for 9-oxysulfur 𠮿

Series compounds; camphorquinone; halogenated ketones; acyl phosphine oxide; acyl phosphonate and the like.

The content of the photo-radical polymerization initiator in the adhesive composition is preferably 20% by mass or less, and is preferably 0.01-20% by mass, more preferably 0.05-10% by mass, and particularly preferably 0.1-5% by mass.

When the adhesive composition of the present invention uses a visible light curable containing a radical polymerizable compound as a curable component, it is particularly suitable to use a photoradical polymerization initiator that has high sensitivity to light of 380 nm or more. The photo-radical polymerization initiator with high sensitivity to light above 380nm will be described later.

(式中，R⁶ 及R⁷ 表示-H、-CH₂ CH₃ 、-iPr或Cl，且R⁶ 及R⁷ 可相同或相異)。相較於單獨使用對380nm以上的光有高感度之光自由基聚合引發劑的情形，使用通式(3)所示化合物時之接著性較佳。通式(3)所示化合物當中，以R⁶ 及R⁷ 為-CH₂ CH₃ 之二乙基9-氧硫𠮿

尤佳。接著劑組成物中通式(3)所示化合物之組成比率，以相對於接著劑組成物之總量為0.1~5質量%為佳，0.5~4質量%較佳，而0.9~3質量%更佳。The aforementioned photo-radical polymerization initiator should preferably use the compound represented by the following general formula (3) alone or in combination with the compound represented by the general formula (3) and the photo-radical polymerization initiator with high sensitivity to light above 380 nm; [ Chemical formula 7]

(In the formula, R ⁶ and R ⁷ represent -H, -CH ₂ CH ₃ , -iPr or Cl, and R ⁶ and R ⁷ may be the same or different). Compared with the case of using a photoradical polymerization initiator with high sensitivity to light of 380 nm or more, the adhesiveness is better when the compound represented by the general formula (3) is used. Among the compounds represented by the general formula (3), R ⁶ and R ⁷ are -CH ₂ CH ₃ diethyl 9-oxysulfur 𠮿

Especially good. The composition ratio of the compound represented by the general formula (3) in the adhesive composition is preferably 0.1 to 5% by mass relative to the total amount of the adhesive composition, preferably 0.5 to 4% by mass, and 0.9 to 3% by mass Better.

In addition, it is suitable to add a polymerization initiation assistant as necessary. Examples of the polymerization initiation aid include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylamine benzoic acid, methyl 4-dimethylamine benzoate, and 4-dimethylamine benzoic acid. Ethyl, isoamyl 4-dimethylaminobenzoate, etc., and ethyl 4-dimethylaminobenzoate is particularly preferred. When the polymerization initiation assistant is used, its addition amount is generally 0-5 mass% relative to the total amount of the adhesive composition, preferably 0-4 mass%, and optimally 0-3 mass%.

In addition, a known photo-radical polymerization initiator can be used as needed. The transparent protective film with UV absorption energy does not transmit light below 380nm, so the photoradical polymerization initiator should preferably use a photoradical polymerization initiator with high sensitivity to light above 380nm. Specifically, for example, 2-methyl-1-(4-methylthiophenyl)-2-morpholinylpropan-1-one, 2-benzyl-2-dimethylamino-1-( 4-Moflinylphenyl)-butan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-Mofol Linyl) phenyl)-1-butanone, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzyl) -Phenylphosphine oxide, bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium Wait.

(式中，R⁸ 、R⁹ 及R¹⁰ 表示-H、-CH₃ 、-CH₂ CH₃ 、-iPr或Cl，且R⁸ 、R⁹ 及R¹⁰ 可相同或相異)。通式(4)所示化合物可適當使用亦屬市售品的2-甲-1-(4-甲基硫基苯基)-2-嗎福林基丙-1-酮(商品名：IRGACURE907，製造商：BASF)。除此之外，2-苄-2-二甲胺基-1-(4-嗎福林基苯基)-丁-1-酮(商品名：IRGACURE369，製造商：BASF)、2-(二甲胺基)-2-[(4-甲基苯基)甲基]-1-[4-(4-嗎福林基)苯基]-1-丁酮(商品名：IRGACURE379，製造商：BASF)由於感度高，因此較佳。In particular, in addition to the photo-radical polymerization initiator of the general formula (3), the photo-radical polymerization initiator also preferably uses the compound represented by the following general formula (4): [Chemical formula 8]

(In the formula, R ⁸ , R ⁹ and R ¹⁰ represent -H, -CH ₃ , -CH ₂ CH ₃ , -iPr or Cl, and R ⁸ , R ⁹ and R ¹⁰ may be the same or different). As the compound represented by the general formula (4), 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholinylpropan-1-one (trade name: IRGACURE907), which is also a commercially available product, can be suitably used. , Manufacturer: BASF). In addition, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butan-1-one (trade name: IRGACURE369, manufacturer: BASF), 2-(two Methylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (trade name: IRGACURE379, manufacturer: BASF) is better because of its high sensitivity.

In the above-mentioned adhesive composition, when a radical polymerizable compound having an active methylene group is used as the radical polymerizable compound, it is preferably used in combination with a radical polymerization initiator having a hydrogen abstraction effect. With this configuration, the adhesiveness of the adhesive layer of the polarizing film can be significantly improved even after being taken out of a high-humidity environment or water (non-dried state). This reason has not been clarified, but it can be presumed to be the following reason. That is, the radically polymerizable compound having a living methylene group is polymerized with other radically polymerizable compounds constituting the adhesive layer while being incorporated into the main chain and/or side chain of the base polymer in the adhesive layer. An adhesive layer is formed. In the aforementioned polymerization process, once there is a radical polymerization initiator with hydrogen abstraction, it will form the base polymer constituting the adhesive layer while abstracting hydrogen from the radical polymerizable compound with active methylene groups. Methylene produces free radicals. As a result, the methylene group that has generated free radicals reacts with the hydroxyl group of the polarizing member such as PVA to form a covalent bond between the adhesive layer and the polarizing member. As a result, it can be inferred that even in a non-dried state, the adhesiveness of the adhesive layer of the polarizing film will still 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以9-氧硫𠮿

系自由基聚合引發劑為佳。作為9-氧硫𠮿

系自由基聚合引發劑，可舉例如上述通式(3)所示化合物。通式(3)所示化合物之具體例可舉出9-氧硫𠮿

系、二甲基9-氧硫𠮿

系、二乙基9-氧硫𠮿

、異丙基9-氧硫𠮿

系、氯9-氧硫𠮿

系等。通式(3)所示化合物當中，以R⁶ 及R⁷ 為-CH₂ CH₃ 之二乙基9-氧硫𠮿

尤佳。In the present invention, the radical polymerization initiator with hydrogen abstraction can include, for example, 9-oxysulfur 𠮿

-Based radical polymerization initiators, benzophenone-based radical polymerization initiators, etc. The aforementioned free radical polymerization initiator is 9-oxysulfur 𠮿

It is preferably a radical polymerization initiator. As 9-oxysulfur 𠮿

The radical polymerization initiator includes, for example, the compound represented by the above-mentioned general formula (3). Specific examples of the compound represented by the general formula (3) can include 9-oxysulfur 𠮿

Department, dimethyl 9-oxysulfur 𠮿

Department, diethyl 9-oxysulfur 𠮿

, Isopropyl 9-oxysulfur 𠮿

Department, chlorine 9-oxysulfur 𠮿

Department etc. Among the compounds represented by the general formula (3), R ⁶ and R ⁷ are -CH ₂ CH ₃ diethyl 9-oxysulfur 𠮿

Especially good.

Cationic polymerizable compounds are classified into monofunctional cationically polymerizable compounds having one cationically polymerizable functional group in the molecule, and polyfunctional cationically polymerizable compounds having two or more cationically polymerizable functional groups in the molecule.

The liquid viscosity of the monofunctional cation polymerizable compound is relatively low, so by containing it in the adhesive composition, the liquid viscosity of the adhesive composition can be reduced. In addition, most of the monofunctional cationically polymerizable compounds have functional groups capable of expressing various functions. By including them in the adhesive composition, the adhesive composition and/or the cured product of the adhesive composition can exhibit various functions.

The polyfunctional cationic polymerizable compound can cause three-dimensional crosslinking of the cured product of the adhesive composition.

Examples of the cationically polymerizable functional group include an epoxy group, an oxetanyl group, and a vinyl ether group.

The epoxy group-containing compound may be an aliphatic epoxy compound, an alicyclic epoxy compound, and an aromatic epoxy compound. From the viewpoint of excellent curability or adhesiveness, an alicyclic epoxy compound is preferable.

Examples of the alicyclic epoxy compound include: 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate, 3,4-epoxycyclohexylmethyl-3,4-ring A modified product of caprolactone, a modified product of trimethylcaprolactone, a modified product of valerolactone, etc. of oxycyclohexane carboxylate. Specifically, CELLOXIDE 2021, CELLOXIDE 2021A, CELLOXIDE 2021P, CELLOXIDE 2081, CELLOXIDE 2083, CELLOXIDE 2085 (above, manufactured by DAICEL Chemical Industries, Ltd.), Cyracure UVR-6105, Cyracure UVR-6107, Cyracure 30, R-6110 ( The above is made by DOW CHEMICAL Japan Co., Ltd.) and so on.

Examples of compounds having an oxetanyl group include: 3-ethyl-3-hydroxymethyloxetane, 1,4-bis[(3-ethyl-3-oxetanyl)methoxy Methyl]benzene, 3-ethyl-3-(phenoxymethyl)oxetane, bis[(3-eth-3-oxetanyl)methyl]ether, 3-ethyl- 3-(2-Ethylhexyloxymethyl)oxetane, phenol novolac oxetane, etc. Specifically, ARON OXETANE OXT-101, ARON OXETANE OXT-121, ARON OXETANE OXT-211, ARON OXETANE OXT-221, ARON OXETANE OXT-212 (above, manufactured by Toagosei Co., Ltd.), etc.

Examples of compounds with vinyl ether groups include: 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, and triethylene diethylene glycol. Alcohol divinyl ether, cyclohexane dimethanol divinyl ether, cyclohexane dimethanol monovinyl ether, tricyclodecane vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, ethyl Oxyethyl vinyl ether, neopentyl erythritol type tetravinyl ether, etc.

From the viewpoint of improving the adhesion of the adhesive layer, the content of the cationic polymerizable compound in the adhesive composition is preferably 5-40% by mass, more preferably 10-30% by mass, and more preferably 15-25% by mass.

The adhesive composition of the present invention contains a cationic polymerizable compound as a curable component, and therefore preferably contains a photocationic polymerization initiator. The photocationic polymerization initiator is irradiated with active energy rays such as visible rays, ultraviolet rays, X-rays, electron beams, etc., to generate cationic species or Lewis acid, and initiate the polymerization reaction of epoxy groups or oxetanyl groups. As a photocationic polymerization initiator, a photoacid generator and a photobase generator can be used, and the photoacid generator mentioned later can be used suitably. In addition, when the adhesive composition used in the present invention is curable with visible light, it is preferable to use a photocationic polymerization initiator that is particularly sensitive to light above 380 nm, but the photocationic polymerization initiator is generally at 300 nm A compound that shows great absorption in the vicinity or a wavelength region shorter than it, so it can be achieved by blending a photosensitizer that shows great absorption to a longer wavelength region, specifically, light with a wavelength longer than 380nm. It senses light of a wavelength near it, and promotes the production of cationic species or acid from the photocationic polymerization initiator. Examples of photosensitizers include anthracene compounds, pyrene compounds, carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo and diazo compounds, halogen compounds, and photoreducible dyes, etc. They may also be used Mix two or more kinds to use. In particular, anthracene compounds are very desirable because of their excellent photosensitizing effect, and specific examples include ANTHRACURE UVS-1331 and ANTHRACURE UVS-1221 (manufactured by Kawasaki Chemical Co., Ltd.). The content of the photosensitizer is preferably 0.1% by mass to 5% by mass, and more preferably 0.5% by mass to 3% by mass.

(惟，L⁺ 表示任意的鎓陽離子；又，X^- 表示選自於由PF₆ ^- 、SbF₆ ^- 、AsF₆ ^- 、SbCl₆ ^- 、BiCl₅ ^- 、SnCl₆ ^- 、ClO₄ ^- 、二硫代胺甲酸鹽陰離子、SCN-所構成群組中的相對陰離子)。Examples of the photoacid generator include compounds represented by the following general formula (5). General formula (5) [Chemical formula 9]

(However, L ⁺ represents an arbitrary cation; and, X ^- represents a group selected consisting of _{^{PF 6 -, SbF 6 -,}} AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, disulfide The relative anion in the group consisting of carbamic acid salt anion and SCN-).

^{Next, the relative anion X −} in the general formula (5) will be described.

^{The relative anion X-} in the general formula (5) is not particularly limited in principle, but a non-nucleophilic anion is preferred. When the relative anion X ^{-is a} non-nucleophilic anion, it is difficult to cause the nucleophilic reaction of the cations coexisting in the molecule or the various materials used in combination to occur. As a result, the photoacid generator represented by the general formula (5) itself or The use of the composition has its long-term stability. The non-nucleophilic anion here refers to an anion with a low ability to initiate a nucleophilic reaction. Examples of the anion includes, for example _{^{PF 6 -, SbF 6 -,}} AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, dithio amine formate anion, SCN ^- and the like.

Preferred specific examples of the photoacid generator of the present invention include "Cyracure-UVI-6992", "Cyracure-UVI-6974" (the above are made by DOW CHEMICAL Japan Co., Ltd.), and "ADEKA OPTOMER SP150" , "ADEKA OPTOMER SP152", "ADEKA OPTOMER SP170", "ADEKA OPTOMER SP172" (the above are manufactured by ADEKA Co., Ltd.), "IRGACURE250" (manufactured by Ciba Specialty Chemicals), " CI-5102", "CI-2855" (Above are manufactured by Soda Corporation of Japan), "SANEIDO SI-60L", "SANEIDO SI-80L", "SANEIDO SI-100L", "SANEIDO SI-110L", "SANEIDO SI -180L" (The above is made by Sanxin Chemical Co., Ltd.), "CPI-100P", "CPI-110P", "CPI-100A" (The above is made by Sanya Pro (SAN-APRO) Co., Ltd.), "WPI-069" , "WPI-113", "WPI-116", "WPI-041", "WPI-044", "WPI-054", "WPI-055", "WPAG-281", "WPAG-567", " WPAG-596" (The above is made by Wako Pure Chemical Industries, Ltd.).

The content of the photoacid generator relative to the total amount of the adhesive composition is 10% by mass or less, and is preferably 0.01-10% by mass, preferably 0.05-5% by mass, and particularly preferably 0.1-3% by mass.

The photobase generator is a photobase generator that can change the molecular structure or crack the molecule by light irradiation such as ultraviolet rays or visible rays, and function as a catalyst for the polymerization reaction of radical polymerizable compounds or epoxy resins, generating more than one base Compounds of sexual substances. Examples of basic substances include secondary amines and tertiary amines. Examples of photobase generators include the above-mentioned α-aminoacetophenone compounds, the above-mentioned oxime ester compounds, or those having an oxyimino group, an N-methylated aromatic amino group, and an N-acylated aromatic group. Compounds with substituents such as amine groups, nitrobenzyl carbamate groups, and alkoxybenzyl carbamate groups. Among them, oxime ester compounds are preferred.

The compound having an oxyimino group can include, for example, O,O'-succinic acid benzophenone oxime, O,O'-succinic acid benzophenone oxime, benzophenone oxime acrylate-styrene copolymer .

Compounds having N-formylated aromatic amine groups and N-formylated aromatic amine groups include, for example, two-N-(p-formylamino) diphenylmethane, two-N(p-acetamide) Yl) diphenylmethane, bis-N-(p-benzamide) diphenylmethane, 4-methamido stilbene, 4-acetamido stilbene, 2,4-dimethyl sulfide Amino stilbene, 1-methamidonaphthalene, 1-acetamido naphthalene, 1,5-dimethylamido naphthalene, 1-methamidoanthracene, 1,4-dimethylamido naphthalene Anthracene, 1-acetylaminoanthracene, 1,4-dimethylaminoanthraquinone, 1,5-dimethylaminoanthraquinone, 3,3'-dimethyl-4,4'-dimethyl Amido biphenyl, 4,4'-dimethylamido diphenyl ketone.

Compounds having a nitrobenzyl carbamate group and an alkoxybenzyl carbamate group include, for example, bis{{(2-nitrobenzyl)oxy}carbonyl}diaminodiphenylmethane, 2 ,4-bis{(2-nitrobenzyl)oxy}stilbene, bis{(2-nitrobenzyloxy)carbonyl}hexane-1,6-diamine and stubble amine {{( 2-Nitro-4-chlorobenzyl)oxy}amide}.

The photobase generator is preferably at least one of an oxime ester compound and an α-aminoacetophenone compound, and more preferably an oxime ester compound. The α-aminoacetophenone compound is particularly preferably one having two or more nitrogen atoms.

Other photobase generators can also use WPBG-018 (trade name: 9-anthrylmethyl N,N'-diethylcarbamate), WPBG-027 (trade name: (E)-1-[3-(2-hydroxyphenyl)-2- propenoyl]piperidine), WPBG-082 (trade name: guanidinium2-(3-benzoylphenyl)propionate), WPBG-140 (trade name: 1-(anthraquinon-2-yl)ethyl imidazolecarboxylate) and other photobase generators.

The above-mentioned adhesive composition may use a photoacid generator and a compound containing either an alkoxy group or an epoxy group in the adhesive composition.

When using a compound with more than one epoxy group in the molecule or a polymer (epoxy resin) with more than two epoxy groups in the molecule, it can also be used in combination with more than two epoxy groups in the molecule. Base compound. The functional group reactive with an epoxy group here includes, for example, 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, it is better to have two or more of these functional groups in one molecule.

Examples of polymers with more than one epoxy group in the molecule include epoxy resins, and there are bisphenol A type epoxy resins derived from bisphenol A and epichlorohydrin, and bisphenol F and epichlorohydrin. Derived bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F phenolic resin Varnish type epoxy resin, alicyclic epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, sulphur type epoxy resin, trifunctional Polyfunctional epoxy resin such as type epoxy resin or tetrafunctional type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, trimeric isocyanate type epoxy resin Resins, aliphatic chain epoxy resins, etc., these epoxy resins can be halogenated or hydrogenated. Commercially available epoxy resin products include, for example, JERCoat 828, 1001, 801N, 806, 807, 152, 604, 630, 871, YX8000, YX8034, YX4000 manufactured by Japan Epoxy Resins Co., Ltd.; Epiclon 830 manufactured by DIC Co., Ltd. EXA835LV, HP4032D, HP820; EP4100 series, EP4000 series, EPU series manufactured by ADEKA Co., Ltd.; CELLOXIDE series (2021, 2021P, 2083, 2085, 3000, etc.) manufactured by DAICEL Chemical Co., Ltd., EPOLEAD series, EHPE series; Nippon Steel YD series, YDF series, YDCN series, YDB series, phenoxy resins manufactured by the chemical company (polyhydroxy polyether synthesized from bisphenols and epichlorohydrin with epoxy groups at both ends; YP series, etc.) ; DENACOL series manufactured by NAGASE CHEMTEX; Epolite series manufactured by Kyoeisha Chemical Company, etc., but not subject to these restrictions. These epoxy resins can also use 2 or more types together.

The compound having an alkoxy group in the molecule is not particularly limited as long as it has one or more alkoxy groups in the molecule, and a known compound can be used. Such compounds can be exemplified by melamine compounds, amine-based resins, and silane coupling agents.

Relative to the total amount of the adhesive composition, the blending amount of the compound containing either an alkoxy group or an epoxy group is usually 30% by mass or less. If the content of the compound in the composition is too large, the adhesiveness will decrease , The impact resistance of the drop test may deteriorate. The content of the compound in the composition is preferably 20% by mass or less. On the other hand, from the viewpoint of water resistance, the composition preferably contains 2% by mass or more of the compound, and more preferably 5% by mass or more.

The adhesive composition used in the present invention preferably contains the aforementioned polymerizable compound X as a curable component. The SP value of the aforementioned polymerizable compound X is similar to that of transparent protective films such as unsaponified cellulose triacetate film and acrylic film. Therefore, the aforementioned polymerizable compound X helps to improve the adhesion between the adhesive layer and the transparent protective film. .

The content of the aforementioned polymerizable compound X in the adhesive composition is not particularly limited, but from the viewpoint of improving the adhesion between the adhesive layer and the transparent protective film, 80% by mass or less is preferable, and 60% by mass or less is more preferable. Furthermore, 25% by mass or more is preferable, and 35% by mass or more is more preferable.

In the present invention, the compound described in the aforementioned general formula (1), preferably the compound described in the aforementioned general formula (1'), and more preferably the compound described in the aforementioned general formula (1a) to (1d) can be blended In the adhesive composition. Furthermore, in the present invention, the aforementioned organometallic compound may be blended into the adhesive composition. When these compounds are blended into the adhesive composition, it is better to improve the adhesion with the polarizer or the transparent protective film. From the viewpoint of improving the adhesiveness and water resistance when the polarizer and the transparent protective film are bonded through the adhesive layer, the content of the compound described in the aforementioned general formula (1) in the adhesive composition is preferably 0.001-50% by mass. It is more preferably 0.1-30% by mass, and more preferably 1-10% by mass. In addition, in the adhesive composition, the content of the aforementioned organometallic compound is preferably 0.1 to 10% by mass, more preferably 0.5 to 7% by mass, and more preferably 1 to 5% by mass.

The bubble inhibitor is a compound that can reduce the surface tension of the adhesive composition by blending it, thereby having the effect of reducing bubbles between the laminated transparent protective film. The bubble inhibitor can be used to reduce the surface tension when added to the adhesive composition, such as: polydimethylsiloxane and other polysiloxane-based bubble inhibitors having a polysiloxane skeleton, (former (Meth)acrylic-based bubble inhibitors with (meth)acrylic acid-based skeletons, vinyl ethers or cyclic ethers, etc., which are formed by polymerization of acrylates, etc. Fluorine bubble suppressant composed of perfluoroalkyl fluorine compounds.

The bubble inhibitor preferably has a reactive group in the compound. At this time, when laminating polarizers and transparent protective films, the occurrence of laminated bubbles can be reduced. The reactive group possessed by the bubble suppressor may include a polymerizable functional group, specifically, for example, a radical polymerizable functional group having an ethylenic double bond such as (meth)acrylic acid group, vinyl group, and allyl group. ; Epoxy groups such as glycidyl groups, oxetanyl groups, vinyl ether groups, cyclic ether groups, cyclic thioether groups, lactone groups and other cationically polymerizable functional groups. From the viewpoint of reactivity in the adhesive composition, a bubble inhibitor having a double bond as a reactive group is preferable, and a bubble inhibitor having a (meth)acrylic acid group is more preferable.

Considering the effect of suppressing build-up bubbles and improving adhesion, polysiloxane-based bubble inhibitors are preferred among the aforementioned bubble inhibitors. In addition, in the bubble inhibitor, when considering the adhesiveness of the adhesive layer, it is preferable that the main chain skeleton or the side chain contains a urethane bond or a trimeric isocyanate ring structure. As the polysiloxane-based bubble suppressor, commercially available products can also be suitably used, for example, "BYK-UV3505" (manufactured by BYK Japan) made of acryl-based modified polydimethylsiloxane.

In order to take into account both the adhesive force of the resulting adhesive layer and the effect of reducing the build-up bubbles, when the total amount of the adhesive composition is set to 100% by mass, the content of the bubble inhibitor is preferably 0.01 to 0.6% by mass.

The adhesive composition used in the present invention may contain, in addition to the curable component of the radical polymerizable compound, an acrylic oligomer formed by polymerizing (meth)acrylic monomers. Since the acrylic oligomer is contained in the adhesive composition, the curing shrinkage can be reduced when the composition is irradiated with active energy rays to make it harden, and the adhesive, polarizer, transparent protective film and other adherends can be reduced. Interface stress. As a result, the adhesion between the adhesive layer and the adherend can be prevented from decreasing. In order to sufficiently suppress the curing shrinkage of the adhesive layer, the content of the acrylic oligomer is preferably 20% by mass or less, preferably 15% by mass or less, relative to the total amount of the adhesive composition. If the content of the acrylic oligomer in the adhesive composition is too large, the reaction rate will be drastically reduced after the composition is irradiated with active energy rays, resulting in poor curing. On the other hand, the acrylic oligomer preferably contains 3% by mass or more with respect to the total amount of the adhesive composition, and more preferably 5% by mass or more.

Considering the workability and uniformity during coating, the adhesive composition is preferably low viscosity, so the acrylic oligomer polymerized by (meth)acrylic monomer is also preferably low viscosity. As an acrylic oligomer with low viscosity and capable of preventing the hardening and shrinkage of the adhesive layer, the weight average molecular weight (Mw) is preferably 15,000 or less, preferably 10,000 or less, and particularly preferably 5,000 or less. On the other hand, in order to sufficiently suppress the curing shrinkage of the adhesive layer, the weight average molecular weight (Mw) of the acrylic oligomer is preferably 500 or more, preferably 1000 or more, and particularly preferably 1500 or more. The (meth)acrylic monomer constituting the acrylic oligomer, specifically, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, (meth) Isopropyl acrylate, 2-methyl-2-nitropropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, S-butyl (meth)acrylate, ( Tertiary butyl meth)acrylate, n-pentyl (meth)acrylate, tertiary pentyl (meth)acrylate, 3-pentyl (meth)acrylate, 2,2-dimethyl (meth)acrylate Butyl ester, n-hexyl (meth)acrylate, cetyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-(meth)acrylate (Meth) acrylic acid (carbon number 1-20) alkyl esters such as 2-propylpentyl ester and N-octadecyl (meth)acrylate; and, for example, cycloalkyl (meth)acrylate (for example, ( Cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate, etc.), aralkyl (meth)acrylate (for example, benzyl (meth)acrylate, etc.), polycyclic (meth)acrylate ( For example, 2-isobornyl (meth)acrylate, 2-norbornyl methyl (meth)acrylate, 5-norbornen-2-yl-methyl (meth)acrylate, 3-norbornyl (meth)acrylate Methyl-2-norbornyl methyl ester, etc.), hydroxyl-containing (meth)acrylates (for example, hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2,3-dihydroxy Propylmethyl-butyl (meth)methacrylate, etc.), (meth)acrylates containing alkoxy or phenoxy groups (2-methoxyethyl (meth)acrylate, (meth) Base) 2-ethoxyethyl acrylate, 2-methoxymethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylic acid Ester, phenoxyethyl (meth)acrylate, etc.), epoxy-containing (meth)acrylates (for example, glycidyl (meth)acrylate, etc.), halogen-containing (meth)acrylates (E.g. 2,2,2-trifluoroethyl (meth)acrylate, 2,2,2-trifluoroethyl ethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, (methyl) ) Hexafluoropropyl acrylate, octafluoropentyl (meth)acrylate, heptafluorodecyl (meth)acrylate, etc.), alkylaminoalkyl (meth)acrylate (e.g. dimethylaminoethyl) (Meth)acrylate etc.) and so on. These (meth)acrylates can be used individually or in combination of 2 or more types. Specific examples of acrylic oligomers include "ARUFON" manufactured by Toagosei Co., Ltd., "ACTFLOW" manufactured by Soken Chemical Co., Ltd., and "JONCRYL" manufactured by BASF JAPAN.

When the adhesive composition used in the present invention is active energy ray curable, the silane coupling agent preferably uses an active energy ray curable compound, but even if it is not active energy ray curable, it can still impart the same water resistance.

Specific examples of silane coupling agents include vinyl trichlorosilane, vinyl trimethoxy silane, vinyl triethoxy silane, 2-(3,4 epoxycyclohexyl) as active energy ray-curable compounds. ) Ethyl trimethoxy silane, 3-glycidoxy propyl trimethoxy silane, 3-glycidoxy propyl methyl diethoxy silane, 3-glycidoxy propyl triethyl Oxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methyl Acrylic oxypropyl methyl diethoxysilane, 3-methacryloxy propyl triethoxy silane, 3-acryloxy propyl trimethoxy silane, etc.

Preferred are 3-methacryloxypropyl trimethoxysilane and 3-acryloxypropyl trimethoxysilane.

In terms of specific examples of the silane coupling agent that is not curable with active energy rays, a silane coupling agent having an amine group is preferred. Specific examples of silane coupling agents with amino groups include: γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, and γ-aminopropyl Methyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-(2-aminoethyl)aminopropyl trimethoxysilane, γ-(2-aminoethyl)aminopropyl Methyldimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropylmethyldiethoxysilane, γ-( 2-aminoethyl)aminopropyl triisopropoxysilane, γ-(2-(2-aminoethyl)aminoethyl)aminopropyl trimethoxysilane, γ-(6-aminohexyl)aminopropyl Trimethoxysilane, 3-(N-ethylamino)-2-methylpropyltrimethoxysilane, γ-ureapropyltrimethoxysilane, γ-ureapropyltriethoxysilane, N- Phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl-γ-aminopropyltriethoxysilane, N-cyclohexyl Aminomethyltriethoxysilane, N-cyclohexylaminomethyldiethoxymethylsilane, N-phenylaminomethyltrimethoxysilane, (2-aminoethyl)aminomethyltrimethoxysilane , N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine and other amino-containing silanes; N-(1,3-dimethylbutylene)-3-(triethyl (Oxysilyl)-1-propylamine and other ketimine silanes.

The silane coupling agent having an amine group may be used only by one type, or may be used in combination of a plurality of types. Among them, 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-propaneamine is preferred.

The blending amount of the silane coupling agent is preferably in the range of 0.01-20% by mass relative to the total amount of the adhesive composition, preferably 0.05-15% by mass, and more preferably 0.1-10% by mass. When the blending amount is more than 20% by mass, the storage stability of the adhesive composition will deteriorate, and when it is less than 0.1% by mass, the effect of water-resistant adhesiveness cannot be fully exhibited.

Specific examples of non-active energy ray-curable silane coupling agents other than the above include: 3-ureapropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethyldimethyl Oxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl) tetrasulfide, 3-isocyanatepropyltriethoxysilane, imidazole silane, etc.

When the adhesive composition used in the present invention contains a compound having a vinyl ether group, the water resistance of the polarizer and the adhesive layer will be improved, so it is ideal. Although the reason for this effect is not clear, it can be presumed that one of the reasons is that the vinyl ether group of the compound interacts with the polarizing member, thereby increasing the adhesion between the polarizing member and the adhesive layer. In order to further improve the water resistance of the polarizer and the adhesive layer, the compound is preferably a radical polymerizable compound with a vinyl ether group. In addition, the content of the compound is preferably 0.1-19% by mass relative to the total amount of the adhesive composition.

The adhesive composition used in the present invention may contain a compound capable of producing keto-enol tautomerism. For example, in an adhesive composition containing a cross-linking agent or an adhesive composition in which a cross-linking agent is blended for use, a form containing the above-mentioned compound capable of producing keto-enol tautomerism can be suitably adopted. Thereby, the excessive increase in viscosity or gelation of the adhesive composition after the blending of the organometallic compound and the formation of microgels can be suppressed, and the effect of prolonging the life span of the composition can be achieved.

Various β-dicarbonyl compounds can be used as the above-mentioned compound capable of producing keto-enol tautomerism. Specific examples include: acetone, 2,4-hexanedione, 3,5-heptanedione, 2-methylhexan-3,5-dione, 6-methylheptane-2,4-dione , 2,6-Dimethylheptane-3,5-dione and other β-diketones; methyl acetylacetate, ethyl acetylacetate, isopropyl acetylacetate, tertiary butyl acetylacetate Acetyl acetates; ethyl acrylate, ethyl acrylate, isopropyl acrylate, tertiary butyl acrylate, etc. Acetate esters; ethyl isobutyl acetate, isobutyl acetate Isobutyl acetates such as ethyl acetate, isobutyl isopropyl acetate, tertiary butyl isobutyl acetate; malonic acid esters such as methyl malonate and ethyl malonate, etc. Among them, suitable compounds include acetone and acetone acetate. The compound capable of producing keto-enol tautomerism may be used alone or in combination of two or more kinds.

The amount of the compound that can produce keto-enol tautomerism is set to, for example, 0.05 parts by mass to 10 parts by mass, preferably 0.2 parts by mass to 3 parts by mass relative to 1 part by mass of the organometallic compound (e.g. 0.3 parts by mass to 2 parts by mass). If the usage amount of the above-mentioned compound is less than 0.05 parts by mass relative to 1 part by mass of the organometallic compound, it may be difficult to fully exert the effect of use. On the other hand, if the amount of the compound used is more than 10 parts by mass relative to 1 part by mass of the organometallic compound, there will be excessive interaction with the organometallic compound, and it may be difficult to exhibit the desired water resistance.

The adhesive composition of the present invention may contain polyrotaxane. The polyrotaxane has a cyclic molecule, a linear molecule penetrating the opening of the cyclic molecule, and an end capping group, and the end capping group is arranged in such a way that the cyclic molecule will not be separated from the linear molecule Both ends of the linear molecule. The cyclic molecule preferably has a functional group that is hardenable by active energy rays.

The cyclic molecule is not particularly limited as long as the opening of the cyclic molecule has a linear molecule surrounded by a thorn, can move on the linear molecule, and has an active energy ray polymerizable group. In addition, in this specification, the "cyclic" of the "cyclic molecule" means that it is substantially a "cyclic". That is, as long as it can move on a linear molecule, the cyclic molecule may be incompletely closed.

Specific examples of cyclic molecules include cyclic polymers such as cyclic polyethers, cyclic polyesters, cyclic polyetheramines, and cyclic polyamines; and α-cyclodextrin, β-cyclodextrin, and γ-ring Cyclodextrins such as dextrin. Among them, from the viewpoint that it is easier to obtain and can choose a variety of end-capping groups, cyclodextrins such as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin are preferable. Two or more types of cyclic molecules may be mixed in the polyrotaxane or the adhesive.

In the polyrotaxane used in the present invention, the cyclic molecule has an active energy ray polymerizable group. Thereby, even after the polyrotaxane reacts with the active energy ray curable component and is cured, an adhesive with a movable crosslinking point can be obtained. The active energy ray polymerizable group possessed by the cyclic molecule may be a group that can be polymerized with the above-mentioned active energy ray curable compound, and examples include radicals such as (meth)acryloyl and (meth)acryloyloxy groups. Polymeric base.

When cyclodextrin is used as the cyclic molecule, the active energy ray polymerizable group is preferably introduced into the hydroxyl group of the cyclodextrin through any appropriate linker. The number of active energy ray polymerizable groups that the polyrotaxane has in one molecule is preferably 2 to 1280, preferably 50 to 1000, and more preferably 90 to 900.

It is preferable to introduce a hydrophobic modifying group into the cyclic molecule. By introducing a hydrophobic modifying group, the compatibility with the active energy ray hardening component can be improved. In addition, due to the hydrophobicity, it can prevent water from entering the interface between the adhesive layer and the polarizer when used in a polarizing film, and can further improve the water resistance. Examples of the hydrophobic modifying group include polyester chains, polyamide chains, alkyl chains, oxyalkylene chains, and ether chains. Specific examples include the groups described in [0027] to [0042] of WO2009/145073.

A polarizing film that uses a resin composition containing polyrotaxane as an adhesive has good water resistance. The reason for the improved water resistance of the polarizing film is not clear, but we guess as follows. That is, we believe that the mobility of the cyclic molecules of the polyrotaxane makes the cross-linking point movable (the so-called pulley effect), thereby imparting flexibility to the cured adhesive and increasing the adhesion of the unevenness on the surface of the polarizer. As a result, it prevents water from invading the interface between the polarizer and the adhesive layer. And we also believe that the hydrophobicity of the adhesive can be imparted to the adhesive by the polyrotaxane having a hydrophobic modifying group, which also helps to prevent water from invading the interface between the polarizer and the adhesive layer. The content of the polyrotaxane is preferably 2% by mass to 50% by mass relative to the resin composition.

＜Polarizers＞ In the present invention, from the viewpoint of improving the optical durability in a harsh environment under high temperature and high humidity, a thin polarizer with a thickness of 3 µm or more and 15 µm or less should be used as the polarizer, preferably 12 µm or less, and more preferably Below 10µm, especially below 8µm. This thin polarizer has less variation in thickness, good visibility and less dimensional change, so it has excellent durability against thermal shock.

In addition, thin polarizers generally have a low moisture content. Specifically, in most cases, the moisture content is below 15% by mass. Although the low-moisture thin polarizer has the aforementioned effects, on the other hand, it has low reactivity with the boron-containing compound or organometallic compound contained in the easy-to-bond composition used in the present invention, thereby improving the polarizer When the effect of adhesion with the adhesive layer is insufficient. Therefore, in the manufacturing method of the polarizing film of the present invention, when using a polarizer with a moisture content of 15% by mass or less, when the total amount of the easy-to-bond composition is set to 100% by mass, the water content is preferably 5 to 90% by mass. 30 to 80% by mass is preferable, and 40 to 70% by mass is more preferable.

The polarizer is made of polyvinyl alcohol resin. Examples of polarizers include hydrophilic polymer films such as polyvinyl alcohol-based films, partially formalized polyvinyl alcohol-based films, and ethylene-vinyl acetate copolymer-based partially saponified films that adsorb iodine or dichroic dyes. Dichroic materials are uniaxially stretched, and polyene-based oriented films such as dehydrated polyvinyl alcohol or dehydrated polyvinyl chloride. Among these, a polarizer composed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is suitable.

The polarizing member in which a polyvinyl alcohol-based film is dyed with iodine and uniaxially stretched can be produced by, for example, immersing polyvinyl alcohol in an iodine aqueous solution for dyeing, and stretching it to 3 to 7 times its original length. If necessary, it may be immersed in an aqueous solution that may also contain potassium iodide such as boric acid, zinc sulfate, and zinc chloride. If necessary, the polyvinyl alcohol-based film may be immersed in water for washing before dyeing. By washing the polyvinyl alcohol-based film with water, the dirt and anti-blocking agent on the surface of the polyvinyl alcohol-based film can be washed away. In addition, by swelling the polyvinyl alcohol-based film, it also has the effect of preventing uneven dyeing. The extension may be performed after dyeing with iodine, or it may be dyed and extended at the same time, or it may be dyed with iodine after extension. It can also be extended in aqueous solutions such as boric acid or potassium iodide or in a water bath.

From the viewpoint of extension stability and humidification reliability, the polarizer should preferably contain boric acid. In addition, from the viewpoint of suppressing the generation of penetrating cracks, the content of boric acid contained in the polarizer is preferably 22% by mass or less, and more preferably 20% by mass or less with respect to the total amount of the polarizer. From the viewpoint of extension stability and humidification reliability, the content of boric acid relative to the total amount of the polarizer is preferably 10% by mass or more, and more preferably 12% by mass or more.

Examples of thin polarizers include: Japanese Patent No. 4751486 specification, Japanese Patent No. 4751481 Specification, Japanese Patent No. 4815544 Specification, Japanese Patent No. 5048120 Specification, International Publication No. 2014/077599 Bulletin Manual, The thin polarizer described in the manual of International Publication No. 2014/077636, etc. or the thin polarizer manufactured by the manufacturing method described in the same.

In the manufacturing method including the stretching step and the dyeing step in the state of a layered body, from the viewpoint that it can be stretched at a high magnification to improve the polarization performance, the aforementioned thin polarizer is described in Japanese Patent No. 4751486 and Japanese Patent No. 4751481. It is preferable to obtain the method described in the specification of Japanese Patent No. 4815544 and Japanese Patent No. 4815544 that includes the step of extending in an aqueous solution of boric acid, and particularly as described in the specification of Japanese Patent No. 4751481 and Japanese Patent No. 4815544. It is preferable to obtain a manufacturing method that includes a step of auxiliary air extension before extension in a boric acid aqueous solution. These thin polarizers can be produced by a manufacturing method including the following steps: a step of stretching a polyvinyl alcohol-based resin (hereinafter, also referred to as PVA-based resin) layer and a resin substrate for stretching in the state of a laminate and dyeing step. As long as this method is used, even if the PVA-based resin layer is thin, it is supported by the resin base material for stretching, so it can be stretched without causing problems such as breakage due to stretching.

＜Transparent protective film＞ The transparent protective film is preferably one that is excellent in transparency, mechanical strength, thermal stability, moisture barrier properties, and isotropy. Examples include polyester-based polymers such as polyethylene terephthalate or polyethylene naphthalate, cellulose-based polymers such as cellulose diacetate or cellulose triacetate, polymethyl methacrylate, etc. Acrylic polymers, styrene polymers such as polystyrene or acrylonitrile-styrene copolymer (AS resin), polycarbonate polymers, etc. In addition, the following polymers can also be cited as examples of polymers forming the above-mentioned transparent protective film: such as polyethylene, polypropylene, polyolefins having cyclic or even norbornene structures, and polyolefin-based polymerization of ethylene-propylene copolymers. Materials, vinyl chloride-based polymers, nylon or aromatic polyamides and other amide-based polymers, imine-based polymers, turbid polymers, polyether-ether-ketone polymers, polyetheretherketone-based polymers, and Phenylene sulfide polymer, vinyl alcohol polymer, chlorinated vinylene polymer, vinyl butyral polymer, aryl ester polymer, polyoxymethylene polymer, epoxy polymer or the above polymerization Blends of materials, etc. The transparent protective film may also contain one or more arbitrary appropriate additives. Examples of additives include ultraviolet absorbers, antioxidants, slip agents, plasticizers, mold release agents, anti-coloring agents, flame retardants, nucleating agents, antistatic agents, pigments, colorants, and the like. The content of the above-mentioned thermoplastic resin in the transparent protective film is preferably 50-100% by mass, preferably 50-99% by mass, more preferably 60-98% by mass, and particularly preferably 70-97% by mass. When the content of the thermoplastic resin in the transparent protective film is 50% by mass or less, the high transparency inherent in the thermoplastic resin may not be sufficiently exhibited.

Also, as a transparent protective film, a polymer film described in Japanese Patent Application Laid-Open No. 2001-343529 (WO01/37007), for example, a polymer film containing (A) having a substituted and/or unsubstituted imino group in the side chain The thermoplastic resin, and the resin composition of the thermoplastic resin having substituted and/or unsubstituted phenyl groups and nitrile groups in the side chain. A specific example may be a film containing a resin composition of an alternating copolymer composed of isobutylene and N-methylmaleimide and an acrylonitrile-styrene copolymer. For the film, a film composed of a mixed extruded product of a resin composition can be used. Due to the small phase difference and low photoelastic coefficient, these films can eliminate the unevenness caused by the strain of the polarizing film, and have excellent humidification durability due to low moisture permeability.

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

The transparent protective film set on one or both sides of the polarizer should be excellent in transparency, mechanical strength, thermal stability, moisture barrier and isotropy, especially the moisture permeability of 150g/m ² /24h The following are preferred, 120g/m ² /24h or less is particularly preferred, and 5~70g/m ² /24h or less is more preferred.

The material for forming a transparent protective film that satisfies the aforementioned low moisture permeability can use polyester resins such as polyethylene terephthalate or polyethylene naphthalate; polycarbonate resins; arylate resins; nylon or aromatics. Amine-based resins such as polyamides; such as polyethylene, polypropylene, polyolefin-based polymers of ethylene-propylene copolymers, cyclic olefin-based resins with cyclic or even norbornene structures, (meth)acrylic Resin, or a mixture of these. Among the aforementioned resins, polycarbonate resins, cyclic polyolefin resins, and (meth)acrylic resins are 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 handling, and thin layer properties, it is preferably 5-100 µm. Especially preferably 10~60μm, 13~40μm is more preferred.

The aforementioned transparent protective film usually uses a front retardation of less than 40 nm and a thickness direction retardation of less than 80 nm. The frontal phase difference Re is represented by Re=(nx-ny)×d. The thickness direction retardation Rth is represented by Rth=(nx-nz)×d. And, the Nz coefficient is represented by Nz=(nx-nz)/(nx-ny). [However, set the refractive index of the slow axis direction, fast axis direction and thickness direction of the film as nx, ny, nz, and d(nm) as the thickness of the film; the slow axis direction as the refractive index in the film plane Become the biggest direction]. In addition, the transparent protective film should be as colorless as possible. A protective film with a retardation value of -90nm~+75nm in the thickness direction can be suitably used. By using the retardation value (Rth) in the thickness direction of -90nm~+75nm, the situation that the transparent protective film causes coloring (optical coloring) of the polarizing film can be almost solved. The retardation value (Rth) in the thickness direction is more preferably -80nm~+60nm, particularly preferably -70nm~+45nm.

On the other hand, as the aforementioned transparent protective film, a retardation plate having a frontal retardation of 40 nm or more and/or a retardation of 80 nm or more in the thickness direction can be used. The frontal phase difference is usually controlled in the range of 40~200nm, and the thickness direction phase difference is usually controlled in the range of 80~300nm. When a phase difference plate is used as a transparent protective film, the phase difference plate can also function as a transparent protective film, so it can be reduced in thickness.

Examples of the retardation plate include a birefringent film obtained by uniaxially or biaxially stretching a polymer material, an oriented film of a liquid crystal polymer, a film supporting an oriented layer of a liquid crystal polymer, and the like. The thickness of the phase difference plate is also not particularly limited, and is generally about 20 to 150 μm. The polymer material can include, for example, polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, poly Carbonate, polyarylate, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polyether sulfide, polyphenylene sulfide, polyphenylene oxide, polyaryl sulfide, polyamide, poly Imidine, polyolefin, polyvinyl chloride, cellulosic resin, cyclic polyolefin resin (norbornene resin), or various copolymers, graft copolymers, blends of these binary and ternary systems Things etc. These polymer materials become oriented objects (stretched films) by stretching or the like.

Examples of the liquid crystal polymer include various main chain types or side chain types in which a conjugated linear atomic group (mesogen) that can impart liquid crystal orientation is introduced into the main chain or side chain of the polymer. Specific examples of the main chain type liquid crystal polymer include a structure in which a mesogen group is bonded to a flexible spacer, such as a nematic polyester-based liquid crystal polymer, a discotic polymer, or a cholesterol type. Polymers, etc. Specific examples of side chain liquid crystal polymers include: polysiloxane, polyacrylate, polymethacrylate, or polymalonate as the main chain skeleton, and a spacer composed of conjugated atomic groups is interposed Those having a mesogen part composed of a para-substituted cyclic compound unit imparting nematic orientation as a side chain, etc. The liquid crystal polymers are formed by the following methods: for example, those that have been rubbed on the surface of a film of polyimide or polyvinyl alcohol formed on a glass plate, and those that have been vapor-deposited with silicon oxide obliquely, etc. On the orientation treatment surface, heat treatment is performed after spreading the liquid crystalline polymer solution.

The retardation plate can be, for example, one that has a proper retardation according to the purpose of use, such as for the purpose of coloring or compensating the viewing angle by using the birefringence of various wavelength plates or liquid crystal layers, or it can be controlled by stacking two or more types of retardation plates. Optical characteristics such as phase difference etc.

The phase difference plate can be selected for various purposes to meet nx=ny＞nz, nx＞ny＞nz, nx＞ny=nz, nx＞nz＞ny, nz=nx＞ny, nz＞nx＞ny, nz＞nx=ny Those who are related to it will use it. In addition, ny=nz not only includes the case where ny and nz are exactly the same, but also the case where ny and nz are substantially the same.

For example, for a retardation plate that satisfies nx>ny>nz, it is advisable to use a frontal retardation that meets 40-100nm, a thickness direction retardation that meets 100-320nm, and an Nz coefficient that meets 1.8-4.5. For example, for a phase difference plate (positive A plate) that satisfies nx>ny=nz, it is advisable to use a phase difference that satisfies 100~200nm. For example, for a phase difference plate (negative A plate) that satisfies nz=nx>ny, it is advisable to use a positive phase difference that satisfies 100~200nm. For example, for a phase difference plate that satisfies nx>nz>ny, it is advisable to use a frontal phase difference that satisfies 150~300nm and the Nz coefficient satisfies greater than 0 to 0.7. Also, as described above, for example, those satisfying nx=ny>nz, nz>nx>ny, or nz>nx=ny can be used.

The transparent protective film can be appropriately selected according to the applied liquid crystal display device. For example, in the case of VA (Vertical Alignment, including MVA and PVA), it is preferable that the transparent protective film on at least one side (cell side) of the polarizing film has a phase difference. As far as the specific phase difference is concerned, the range of Re=0~240nm and Rth=0~500nm is better. In terms of three-dimensional refractive index, nx>ny=nz, nx>ny>nz, nx>nz>ny, nx=ny>nz (positive A plate, biaxial, negative C plate (negative C plate)) The situation is good. VA type is better to use a combination of positive A plate and negative C plate, or a biaxial film. When a polarizing film is used on the top and bottom of the liquid crystal cell, the liquid crystal cell can have a phase difference between the top and bottom, or the transparent protective film that can be either up or down has a phase difference.

For example, in the case of IPS (In-Plane Switching, including FFS), it can be used regardless of whether the transparent protective film on one side of the polarizing film has a phase difference or when there is no phase difference. For example, when there is no phase difference, it is better that the liquid crystal cell has no phase difference above and below (on the cell side). When there is a phase difference, it is better that the liquid crystal cell has a phase difference between the upper and lower sides, and the upper and lower sides have a phase difference (for example, the upper side is a biaxial film that satisfies the relationship nx>nz>ny and the lower side is a case where there is no phase difference, or The case where the upper side is a positive A plate and the lower side is a negative C plate). When there is a phase difference, the range of Re=-500~500nm and Rth=-500~500nm is better. In terms of three-dimensional refractive index, nx>ny=nz, nx>nz>ny, nz>nx=ny, nz>nx>ny (positive A plate, biaxial, negative C plate) are preferable.

In order to supplement the mechanical strength or handleability of the transparent protective film, a peelable substrate may be further laminated. The peelable substrate can be peeled from the laminate containing the transparent protective film and the polarizer before or after the transparent protective film and the polarizer are attached, in this step or in other steps.

＜Manufacturing method of polarizing film＞ Hereinafter, each step in the manufacturing method of the polarizing film of the present invention will be described with reference to FIG. 1.

<The first coating step> The first coating step is a step of applying an easy-to-adhesive composition to the bonding surface of the polarizer 2 while conveying the polarizer 2 to form a wet first coating film. In addition, the easy-adhesive composition can be coated on one side of the polarizer 2 or the easy-adhesive composition can be coated on both sides of the polarizer 2.

＜Second coating step＞ The second coating step is a step of applying the aforementioned adhesive composition to the bonding surface of the transparent protective film 3 while conveying the transparent protective film 3 to form a second coating film.

The polarizer 2 and the transparent protective film 3 may also undergo surface modification treatment before the coating step. It is particularly suitable to perform surface modification treatment on the surface of the polarizer 2. Surface modification treatment can include corona treatment, plasma treatment, excimer treatment and flame treatment, etc., and corona treatment is particularly preferred. By performing corona treatment, reactive functional groups such as carbonyl groups or amine groups can be generated on the surface of the polarizer 2 to improve the adhesion with the adhesive layer. In addition, the ashing effect can remove surface foreign matter and reduce surface irregularities, so a polarizing film with excellent appearance characteristics can be made.

Coating machines 4 and 5 are not particularly limited, and examples include reverse coaters, gravure coaters (direct, reverse and offset), bar reverse coaters, roll coaters, die coaters, bar coaters, and Rod coating machine, etc.

The method of coating the easy-to-adhesive composition on the bonding surface of the polarizing member 2 and the method of coating the adhesive composition on the bonding surface of the transparent protective film 3 can be appropriately selected depending on the viscosity of each composition or the desired thickness. However, from the viewpoints of removing foreign matter on the surface of the polarizer 2 and the transparent protective film 3, coating properties, and controlling the thickness of the coating film, the post-use metering coating method is suitable. Specific examples of the post-metering coating method include a gravure roll coating method, a forward roll coating method, an air knife coating method, and a rod/rod coating method. Among them, the gravure roll coating method is particularly suitable from the viewpoints of removing foreign matter on the surfaces of the polarizing member 2 and the transparent protective film 3, coating properties, and controlling the thickness of the coating film.

In the gravure roll coating method, various patterns can be formed on the surface of the gravure roll, for example, a honeycomb grid pattern, a trapezoidal pattern, a lattice pattern, a pyramid pattern, or a diagonal pattern can be formed. In order to effectively prevent appearance defects of the finally obtained polarizing film, the pattern formed on the surface of the aforementioned gravure roll is preferably a honeycomb grid pattern. When it is a honeycomb grid pattern, in order to improve the surface accuracy of the coated surface after coating, the groove volume should be 1~5cm ³ /m ² , and more preferably 2~3cm ³ /m ² . Also in order to improve the surface accuracy of the coated surface after coating, the number of groove lines per inch of the roller should be 200~3000 lines/inch. In addition, the ratio of the rotation speed of the gravure roll with respect to the traveling speed of the polarizer 2 and the transparent protective film 3 is preferably 100 to 300%.

<The first thickness measurement procedure> The first thickness measurement step is a step for online measurement of the thickness of the wet first coating film. The film thickness meter 6 used for online measurement is preferably an optical (non-contact) film thickness meter. The optical (non-contact) film thickness meter is not particularly limited, and examples thereof include a spectroscopic interference type film thickness meter, a reflection spectroscopic type film thickness meter, and a conjugate focus type film thickness meter. In particular, it is suitable to use the spectroscopic interference film thickness which can measure the thickness of the coating film in the total width.

＜Drying step＞ The easy-to-bond composition contains water, so after measuring the thickness of the wet-type first coating film on-line, the dryer 7 is used to remove the water in the wet-type first coating film. When water remains in the dry first coating film, water will remain in the uncured adhesive layer obtained by bonding the dry first coating film and the second coating film. As a result, problems such as segregation of the polymerization initiator in the uncured adhesive layer and hindrance of cationic hardening of the uncured adhesive layer may occur, resulting in a decrease in the adhesiveness of the adhesive layer. Therefore, a drying step is provided to remove as much water as possible from the wet first coating film. The drying step is a method well-known to those skilled in the art, and can be carried out by air drying, heat drying, or hot air drying, for example.

The temperature of the dryer 7 is not particularly limited, but it is preferably 15-40°C, more preferably 20-35°C. In addition, the air volume of the dryer 7 is not particularly limited, but it is preferably 3.8 to 30.0 m ³ /min per unit width (m), and more preferably 6.0 to 15.5 ^{m 3} /min.

＜Dry degree adjustment procedure＞ After the aforementioned drying step, the thickness of the dry first coating film was measured on-line with a film thickness of 8, and the ratio of the thickness of the wet first coating film obtained by the aforementioned online measurement to the thickness of the dry first coating film satisfies the following In the method of the formula (A), the temperature and/or air volume of the dryer 7 are adjusted to adjust the degree of drying of the dry first coating film to be newly formed. (The thickness of the dry first coating film/the thickness of the wet first coating film)-(the water content in the easy-to-bond composition)≦0.05(A)

(The thickness of the dry first coating film/the thickness of the wet first coating film)-(the water content in the easy-to-bond composition) is preferably 0.04 or less, preferably 0.03 or less, more preferably 0.02 or less.

The film thickness gauge 8 used for online measurement is preferably an optical (non-contact) film thickness gauge. The optical (non-contact) film thickness meter is not particularly limited, and examples of the above-mentioned film thickness meter can be mentioned. In particular, it is preferable to use the spectroscopic interference film thickness which can measure the thickness of the dry first coating film in the total width.

＜Fixing Steps＞ The bonding step is a step of bonding the dry first coating film formed on the bonding surface of the polarizer 2 and the second coating film formed on the bonding surface of the transparent protective film 3 to form an uncured adhesive layer. The bonding can be performed by a roll laminator 9 or the like.

<Next steps> The next step is a step of manufacturing the polarizing film 1 by adhering the polarizer 2 and the transparent protective film 3 through the adhesive layer obtained by curing the uncured adhesive layer.

After the polarizer 2 and the transparent protective film 3 are laminated, active energy rays (electron beams, ultraviolet rays, visible rays, etc.) are irradiated or heated to harden the uncured adhesive layer to form the adhesive layer. The irradiation direction of the active energy rays (electron beam, ultraviolet rays, visible rays, etc.) can be irradiated from any appropriate direction. It is preferable to irradiate from the transparent protective film 3 side. If irradiated from the side of the polarizer 2, the polarizer 2 may deteriorate due to active energy rays (electron beam, ultraviolet rays, visible rays, etc.).

As long as the irradiation conditions when irradiating the electron beam are conditions that can harden the above-mentioned uncured adhesive layer, any appropriate conditions can be adopted. For example, the acceleration voltage when irradiating electron beams should be 5kV~300kV, more preferably 10kV~250kV. When the accelerating voltage is lower than 5kV, the electron beam cannot reach the uncured adhesive layer and there is a risk of insufficient curing; when the accelerating voltage is higher than 300kV, the penetration force will be too strong, and there is a risk of causing damage to the transparent protective film or polarizer. The radiation dose should be 5-100kGy, more preferably 10~75kGy. When the amount of radiation is less than 5kGy, the uncured adhesive layer will not be hardened enough; when it is greater than 100kGy, it will cause damage to the transparent protective film or polarizer, reduce the mechanical strength or produce yellowing, and it may not be able to obtain the predetermined optical properties. tendency.

The electron beam irradiation is usually carried out in an inert gas, but if necessary, it can also be carried out in the atmosphere or with a small amount of oxygen introduced. Although it depends on the material of the transparent protective film, an oxygen barrier is deliberately generated on the transparent protective film surface that the electron beam will initially contact by introducing oxygen appropriately, which prevents damage to the transparent protective film and can efficiently Only the uncured adhesive layer is irradiated with electron beams.

In the manufacturing method of the polarizing film of the present invention, the active energy rays are preferably those that include visible rays in the wavelength range of 380nm~450nm, especially the active energy rays that use the most irradiated amount of visible rays in the wavelength range of 380nm to 450nm. When using ultraviolet or visible light, if a transparent protective film (transparent ultraviolet non-transmissive protective film) with ultraviolet absorbing energy is used, it will absorb light with a wavelength shorter than about 380nm, so light with a wavelength shorter than 380nm will not reach the next It does not help its polymerization reaction. In addition, the light with a wavelength shorter than 380nm absorbed by the transparent protective film will be converted into heat, causing the transparent protective film itself to generate heat, causing the polarizing film to curl, wrinkle and other undesirable causes. Therefore, when ultraviolet rays and visible rays are used in the present invention, the active energy ray generator is preferably a device that does not emit light with a wavelength shorter than 380nm. More specifically, the cumulative illuminance in the wavelength range of 380~440nm and the wavelength range of 250 The ratio of the cumulative illuminance of ~370nm is preferably 100:0 to 100:50, preferably 100:0 to 100:40. In the manufacturing method of the polarizing film of the present invention, the active energy line is preferably a gallium-filled metal halide lamp, and an LED light source with a wavelength range of 380 to 440 nm. Or you can use low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, incandescent bulbs, xenon lamps, halogen lamps, carbon arc lamps, metal halide lamps, fluorescent lamps, tungsten lamps, gallium lamps, excimer-containing lasers or Sunlight and other ultraviolet and visible light sources can also be used with band-pass filters to shield ultraviolet rays with a wavelength shorter than 380nm. In order to improve the bonding performance of the adhesive layer between the polarizer and the transparent protective film, while preventing the polarizing film from curling, it is advisable to use a gallium-filled metal halide lamp and use a bandpass filter that can block light with a wavelength shorter than 380nm. The obtained active energy ray, or the active energy ray with a wavelength of 405 nm obtained by using an LED light source.

It is advisable to heat the unhardened adhesive layer before irradiating ultraviolet rays or visible rays (heating before irradiation). At this time, it is better to heat to 40°C or higher, and it is better to heat to 50°C or higher. In addition, it is also advisable to heat the adhesive layer after irradiating ultraviolet rays or visible rays (heating after irradiation), and at this time, it is better to heat up to 40°C or more, and it is better to heat up to 50°C or more.

The adhesive composition used in the present invention is particularly suitable for forming an adhesive layer for bonding a polarizer to a transparent protective film with a light transmittance of less than 5% at a wavelength of 365 nm. Here, the adhesive composition used in the present invention contains the photo-radical polymerization initiator of the above general formula (3) and irradiates ultraviolet rays through a transparent protective film with UV absorbing energy to harden the adhesive layer. Therefore, even if there is a polarizing film with a UV-absorbing transparent protective film on the two area layers of the polarizer, the adhesive layer can be hardened. Of course, the layered polarizing film with a transparent protective film that does not have UV absorption energy can also harden the adhesive layer. In addition, the so-called transparent protective film with UV absorption energy means a transparent protective film with a transmittance of less than 10% to 380nm light.

The method of imparting UV absorbing energy to the transparent protective film may include a method of containing an ultraviolet absorber in the transparent protective film, or a method of containing a surface treatment layer of the ultraviolet absorber in the surface area of the transparent protective film.

Specific examples of ultraviolet absorbers include, for example, conventionally known oxybenzophenone-based compounds, benzotriazole-based compounds, salicylate-based compounds, benzophenone-based compounds, cyanoacrylate-based compounds, and nickel complexes. Salt-based compounds, three 𠯤-based compounds, etc.

In the manufacturing method of the polarizing film of the present invention, the production line speed depends on the curing time of the uncured adhesive layer, but is preferably 1 to 500 m/min, preferably 5 to 300 m/min, and more preferably 10 to 100 m/min. When the production line speed is too low, productivity is poor, or excessive damage is caused to the transparent protective film, and a polarizing film that can withstand durability tests, etc. cannot be produced. When the production line speed is too high, the curing of the uncured adhesive layer will be insufficient, and the desired adhesiveness may not be obtained in some cases.

＜Adhesive layer＞ The adhesive layer is formed by curing the uncured adhesive layer. The thickness of the adhesive layer is preferably 0.01~3µm. When the thickness of the adhesive layer is too thin, the peeling force is reduced due to insufficient cohesion of the adhesive layer, which is not good. When the thickness of the adhesive layer is too thick, peeling easily occurs when stress is applied to the cross section of the polarizing film, and peeling failure due to impact occurs, which is not good. The thickness of the adhesive layer is preferably 0.1~2.5μm, more preferably 0.5~1.5μm.

＜Optical film＞ In actual use, the polarizing film of the present invention can be used as an optical film laminated with other optical layers. The optical layer is not particularly limited. Examples include retardation films (including 1/2 or 1/4 wavelength plates), visual compensation films, brightness enhancement films, reflective plates, or semi-transmissive plates that can be used to form liquid crystals. Those in the optical layer of display devices.

As the aforementioned retardation film, one having a frontal retardation of 40 nm or more and/or a retardation of 80 nm or more in the thickness direction can be used. The frontal phase difference is usually controlled in the range of 40~200nm, and the thickness direction phase difference is usually controlled in the range of 80~300nm.

Examples of the retardation film include a birefringent film obtained by uniaxially or biaxially stretching a polymer material, an oriented film of a liquid crystal polymer, and an oriented layer of a liquid crystal polymer supported by a film. The thickness of the retardation film is also not particularly limited, and is generally about 20 to 150 μm.

As the retardation film, a reverse wavelength dispersion type retardation film that satisfies the following formulas (1) and (3) can also be used: 0.70＜Re[450]/Re[550]＜0.97…(1) 1.5×10-3＜Δn＜6×10-3…(2) 1.13＜NZ＜1.50…(3) (In the formula, Re[450] and Re[550] are the in-plane retardation values of the retardation film measured at 23°C with wavelengths of 450nm and 550nm, respectively; Δn is the slow axis direction of the retardation film, respectively 、When the refractive index in the fast axis direction is set to nx, ny, the in-plane birefringence of nx-ny; NZ is the in-plane birefringence of the thickness direction birefringence when nz is the refractive index in the thickness direction of the retardation film. Nx-ny ratio of refraction).

It is also possible to provide an adhesive layer for bonding with other components such as liquid crystal cells on the aforementioned polarizing film or an optical film laminated with at least one layer of polarizing film. The adhesive forming the adhesive layer is not particularly limited, and acrylic polymer, silicone polymer, polyester, polyurethane, polyamide, polyether, fluorine-based or rubber-based polymers can be appropriately selected. Used as a base polymer. It is particularly preferable to use an acrylic adhesive that exhibits excellent optical transparency and adhesive properties such as moderate wettability, cohesiveness, and adhesion, and has excellent weather resistance and heat resistance.

The adhesive layer can also be arranged on one side or both sides of the polarizing film or the optical film in the form of overlapping layers of different compositions or types. Moreover, when it is installed on both sides, the front and back of the polarizing film or the optical film can also be made into adhesive layers with different compositions, types, or thicknesses. The thickness of the adhesive layer can be appropriately determined according to the purpose of use or adhesion, etc., generally 1~500µm, preferably 1~200µm, especially 1~100µm.

In order to prevent contamination of the exposed surface of the adhesive layer, it can be temporarily attached and covered with a separate piece during the period before actual use. This prevents contact with the adhesive layer under normal operating conditions. As the separator, in addition to the above-mentioned thickness conditions, suitable articles according to conventional knowledge can be used, for example, plastic films, rubber sheets, paper, cloth, non-woven fabrics, meshes, foam sheets or metal foils and laminates of these can be used. Appropriate thin body such as body is coated with appropriate release agent such as polysiloxane-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide as needed.

＜Video display device＞ The polarizing film or optical film of the present invention can be suitably used in the formation of various devices such as liquid crystal display devices. The formation of the liquid crystal display device can be carried out as before. That is, the liquid crystal display device is generally formed by appropriately assembling the liquid crystal cell, the polarizing film or the optical film, and the component parts such as the lighting system according to the demand, and integrating them into the driving circuit. In the present invention, in addition to using the polarizing film of the present invention The film or optical film is not particularly limited except for this point, and it can follow conventional knowledge. Regarding the liquid crystal cell, any type such as TN type, STN type, and π type can be used.

It can form a liquid crystal display device with a polarizing film or optical film on one side or both sides of the liquid crystal cell, or an appropriate liquid crystal display device such as a backlight or a reflective plate used in the lighting system. At this time, the polarizing film or optical film of the present invention can be arranged on one side or both sides of the liquid crystal cell. When polarizing films or optical films are arranged on both sides, they may be the same or different. In addition, when forming a liquid crystal display device, one layer or two or more layers such as diffuser, anti-glare layer, anti-reflection film, protective plate, ridge array, lens array sheet, light diffuser, and backlight can be arranged in an appropriate position. Appropriate parts such as pieces.

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

＜Polarizers＞ First, a laminate with a 9μm thick PVA layer is formed on an amorphous PET substrate, and the stretched laminate is made by air-assisted stretching at a stretching temperature of 130°C, and then the stretched laminate is dyed to produce a colored laminate. The colored laminate and the amorphous PET substrate were stretched integrally by stretching in boric acid water at a stretching temperature of 65 degrees so that the total stretching ratio was 5.94 times to produce an optical film laminate including a PVA layer with a thickness of 5 μm. By the two-stage extension, an optical film laminate including a PVA layer with a thickness of 5 μm for forming a thin polarizer can be obtained. The PVA molecule of the optical film laminate is formed on the PVA layer of the amorphous PET substrate. Highly oriented, and the iodine adsorbed by dyeing is highly oriented in one direction in the form of polyiodide ion complexes. The moisture content of the thin polarizer (PVA layer) is 10% by mass.

＜Transparent protective film＞ As a transparent protective film, a cycloolefin polymer film with a thickness of 13 µm (manufactured by ZEON, Japan: ZF-14) was used.

<Active energy rays> As the active energy rays, a polarizing film was produced by ^{irradiating ultraviolet rays with a maximum illuminance of 500 mW/cm 2} and a cumulative light amount of 800 mJ/cm ² from the transparent protective film side with a UV irradiation device (high-pressure mercury lamp manufactured by Toshiba Corporation).

＜Preparation of easy-to-bond composition＞ 54 parts by mass of 4-hydroxybutyl acrylate, 1 part by mass of 3-propenylaminophenylboronic acid (manufactured by Junsei Chemical Co., Ltd.), and 45 parts by mass of water were mixed, and stirred at 25°C for 10 minutes to prepare easy Then the composition. In addition, the water content in the easy-to-bond composition was 0.45.

<Preparation of Adhesive Composition> 5 parts by mass of ω-carboxy-polycaprolactone (n≒2) monoacrylate (manufactured by Toagosei Co., Ltd., M5300), 10 parts by mass of isobornyl acrylate, and acrylate mopholine (Manufactured by Xingren Co., Ltd., trade name "ACMO", SP value: 22.9) 20 parts by mass, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate (manufactured by Daicel Chemical Industry Co., Ltd.) , CELLOXIDE 2021P) 10 parts by mass, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide (manufactured by Ciba Specialty Chemicals, TPO) 1 part by mass, and p-phenylthiodiphenyl 2 parts by mass of base PF ₆ salt (manufactured by San-Apro, CPI-110P) were mixed and stirred at 50°C for 1 hour to prepare an adhesive composition.

Example 1 In a continuous production line, using a gravure roller coating method with a gravure roller, the PVA surface of an optical film laminate containing a PVA layer with a thickness of 5µm was coated and prepared with an initial set thickness of 1190nm. It is easy to adhere to the composition to continuously form a wet first coating film. On the other hand, on another continuous production line, using a gravure roller coating method with a gravure roller, the adhesive composition prepared was coated with an initial set thickness of 1500nm on the bonding surface of the aforementioned transparent protective film. The second coating film is continuously formed. Then, the thickness of the aforementioned wet first coating film was measured on the continuous production line with a spectroscopic interference film thickness meter (manufactured by Ocean Optics: Spectroscope "USB2000+", light source "HL-2000", optical fiber "OCF-103995") . And on a continuous production line, while using a dryer at 25°C and ^{an initial setting of 12.5m 3} /min of air volume per unit width (m) to remove the water in the wet first coating film, it interferes with spectroscopy. The thickness of the dry first coating film obtained by measuring the thickness of the dry-type first coating film on-line with a type film thickness meter (manufactured by Ocean Optics: Spectroscope "USB2000+", light source "HL-2000", optical fiber "OCF-103995"), and adjusting the dryer's thickness based on the measurement result The temperature and air volume are used to adjust the degree of dryness of the newly formed dry first coating film. In addition, the degree of dryness of the dry first coating film is adjusted to satisfy the following formula (A), the temperature of the dryer is appropriately adjusted to 22-28°C, and the air volume is appropriately adjusted to 6.0-15.5m ³ / Minutes to proceed. (The thickness of the dry first coating film/the thickness of the wet first coating film)-(The water content in the easy-to-bond composition)≦0.05(A) Next, use a rolling machine to bond the formed optical film laminate The dry first coating film on the bonding surface and the second coating film formed on the bonding surface of the transparent protective film form an uncured adhesive layer. After that, the above-mentioned ultraviolet rays were irradiated with the active energy ray irradiation device from the side of the laminated transparent protective film to allow the polarizer and the transparent protective film to pass through the adhesive layer. Then, they were dried with hot air at 70°C for 3 minutes to remove the amorphous PET The substrate is peeled and removed to obtain a polarizing film with a transparent protective film on one side of the polarizer. The production line speed of laminating is carried out at 25m/min. Through the aforementioned series of steps, the polarizing film was continuously manufactured for 15 hours.

Comparative Example 1 In a continuous production line, using a gravure roller coating method with a gravure roller, the PVA surface of an optical film laminate containing a PVA layer with a thickness of 5µm was coated and prepared with an initial set thickness of 1195nm. It is easy to adhere to the composition to continuously form a wet first coating film. On the other hand, on another continuous production line, using a gravure roller coating method with a gravure roller, the adhesive composition prepared was coated with an initial set thickness of 1500nm on the bonding surface of the aforementioned transparent protective film. The second coating film is continuously formed. Then, the thickness of the aforementioned wet first coating film was measured on the continuous production line with a spectroscopic interference film thickness meter (manufactured by Ocean Optics: Spectroscope "USB2000+", light source "HL-2000", optical fiber "OCF-103995") . And on a continuous production line, use a dryer at 25°C and ^{an initial setting of 12.5m 3} /min of air volume per unit width (m) to remove water in the wet first coating film to form a dry first 1 Coating film. Next, the dry first coating film formed on the bonding surface of the optical film laminate and the second coating film formed on the bonding surface of the transparent protective film were bonded together using a rolling mill to form an uncured adhesive layer. After that, the above-mentioned ultraviolet rays were irradiated with the active energy ray irradiation device from the side of the laminated transparent protective film to allow the polarizer and the transparent protective film to pass through the adhesive layer. Then, they were dried with hot air at 70°C for 3 minutes to remove the amorphous PET The substrate is peeled and removed to obtain a polarizing film with a transparent protective film on one side of the polarizer. The production line speed of laminating is carried out at 25m/min. Through the aforementioned series of steps, the polarizing film was continuously manufactured for 15 hours.

Comparative Example 2 On a continuous production line, using a gravure roller coating method with a gravure roller, the PVA surface of an optical film laminate containing a PVA layer with a thickness of 5 µm was coated with an initial set thickness of 1200 nm. It is easy to adhere to the composition to continuously form a wet first coating film. On the other hand, on another continuous production line, using a gravure roller coating method with a gravure roller, the adhesive composition prepared was coated with an initial set thickness of 1500nm on the bonding surface of the aforementioned transparent protective film. The second coating film is continuously formed. Then, the thickness of the aforementioned wet first coating film was measured on the continuous production line with a spectroscopic interference film thickness meter (manufactured by Ocean Optics: Spectroscope "USB2000+", light source "HL-2000", optical fiber "OCF-103995") . And on a continuous production line, use a dryer at 25°C and ^{an initial setting of 12.5m 3} /min of air volume per unit width (m) to remove water in the wet first coating film to form a dry first 1 Coating film. Next, the dry first coating film formed on the bonding surface of the optical film laminate and the second coating film formed on the bonding surface of the transparent protective film were bonded together using a rolling mill to form an uncured adhesive layer. After that, the above-mentioned ultraviolet rays were irradiated with the active energy ray irradiation device from the side of the laminated transparent protective film to allow the polarizer and the transparent protective film to pass through the adhesive layer. Then, they were dried with hot air at 70°C for 3 minutes to remove the amorphous PET The substrate is peeled and removed to obtain a polarizing film with a transparent protective film on one side of the polarizer. The production line speed of laminating is carried out at 25m/min. Through the aforementioned series of steps, the polarizing film was continuously manufactured for 15 hours.

(Assess adhesion) Cut the polarizing film 5 minutes and 15 hours after the start of manufacturing into a size of 200 mm parallel to the extension direction of the polarizer and 15 mm in the straight direction, and then attach the polarizing film to the glass plate. Then use a utility knife to make a cut mark between the transparent protective film and the polarizer, and use a universal testing machine (TENSILON) to peel the transparent protective film and the polarizer 90 degrees at a peeling speed of 1000 mm/min, and measure the peel strength (N /15mm), evaluate the adhesive force according to the following criteria. ○: When the peeling force is 1N or more ×: When the peeling force is less than 1N

(Assessing bubbles) The number of bubbles was counted by observing both sides of the polarizing film 5 minutes and 15 hours after the start of production with an optical microscope. The number of bubbles is counted within the range of 5cm×5cm. When the total number of bubbles on both sides is less than 3, it is evaluated as ○, and when there are more than 3 bubbles, it is evaluated as ×.

[Table 2]

It can be seen from Table 2 that there is a drying degree adjustment step in Example 1, so the variation of the drying degree of the dry first coating film in continuous production is suppressed, and even 15 hours after the start of production, excellent adhesion can be obtained stably The polarizing film. And it can be seen that the resulting polarizing film has suppressed the generation of bubbles. On the other hand, it can be seen that the drying degree adjustment step was not performed in Comparative Examples 1 and 2, so that the dry first coating film fluctuates greatly in continuous production, and the polarizing film 15 hours after the start of production is left in the first coating film. 1 Water in the coating film hinders the cationic polymerization reaction, so the adhesive layer has a low adhesive force.

Industrial availability The polarizing film of the present invention can be used alone or in the form of an optical film formed by laminating it in image display devices such as liquid crystal display devices (LCD), organic EL display devices, CRTs, and PDPs.

1: Polarizing film 2: Polarizing parts 3: Transparent protective film 4,5: Coating machine 6, 8: Film thickness gauge 7: Dryer 9: Roll laminator

Fig. 1 is a schematic diagram showing an example of a method of manufacturing a polarizing film of the present invention.

1: Polarizing film

2: Polarizing parts

3: Transparent protective film

4,5: Coating machine

6, 8: Film thickness gauge

7: Dryer

9: Roll laminator

Claims (7)

A method for manufacturing a polarizing film. The polarizing film is provided with a transparent protective film through an adhesive layer on at least one side of a polarizer. The manufacturing method is characterized by including the following steps: The first coating step is to apply an easy-adhesion composition containing water and a hydrophilic monomer to the bonding surface of the polarizer while conveying the polarizer to form a wet first coating film; The second coating step is to apply an adhesive composition containing a radical polymerizable compound and a cation polymerizable compound to the bonding surface of the transparent protective film while conveying the transparent protective film to form a second coating film; The first thickness measurement step is to measure the thickness of the aforementioned wet first coating film online; The drying step is after the first thickness measurement step, using a dryer to remove the water in the wet first coating film to form a dry first coating film; The second thickness measurement step is to measure the thickness of the dry first coating film on-line after the drying step; The drying degree adjustment step is to adjust the temperature and temperature of the dryer so that the ratio of the thickness of the wet first coating film to the thickness of the dry first coating film obtained by the online measurement satisfies the following formula (A) / Or air volume, to adjust the degree of dryness of the newly formed dry first coating film; The bonding step is to bond the dry first coating film formed on the bonding surface of the polarizer and the second coating film formed on the bonding surface of the transparent protective film to form an uncured adhesive layer; and The next step is to bond the polarizer and the transparent protective film through the adhesive layer obtained by curing the uncured adhesive layer; (The thickness of the dry first coating film/the thickness of the wet first coating film)-(the water content in the easy-to-bond composition)≦0.05(A). The method of manufacturing a polarizing film according to claim 1, wherein the aforementioned easy-to-bond composition contains the compound represented by the following general formula (1) and/or the structural formula has an MO bond (M-based silicon, titanium, aluminum or zirconium, O-based Oxygen atom) organometallic compound; [Chemical formula 1]

(However, X is a functional group including a reactive group, and R ¹ and R ² each independently represent a hydrogen atom, an aliphatic hydrocarbon group that may have a substituent, an aryl group, or a heterocyclic group). The method for manufacturing a polarizing film according to claim 2, wherein the compound represented by the aforementioned general formula (1) is a compound represented by the following general formula (1'): [Chemical formula 2]

(However, Y is an organic group, and X, R ¹ and R ^{2 are the} same as above). The method for producing a polarizing film according to any one of claim 2 or 3, wherein the reactive group contained in the compound represented by the general formula (1) is selected from the group consisting of α, β-unsaturated carbonyl, vinyl, and vinyl At least one reactive group in the group consisting of an ether group, an epoxy group, an oxetanyl group, an amine group, an aldehyde group, a mercapto group, and a halogen group. The method for manufacturing a polarizing film according to any one of claims 1 to 4, wherein the moisture content of the polarizing member is 15% by mass or less. The method for manufacturing a polarizing film according to any one of claims 1 to 5, wherein the first coating step and the second coating step are coating steps of a post-use metering coating method. The method for manufacturing a polarizing film according to claim 6, wherein the aforementioned post-metering coating method is a gravure roll coating method using a gravure roll.

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