KR100939467B1 - Polarizing plate, manufacturing thereof, optical film and image display - Google Patents

Abstract

(Problem) To provide a polarizing plate in which a polarizer and a transparent protective film are affixed with an active energy ray hardening-type adhesive agent, and have favorable adhesiveness.

(Solution means) A polarizing plate in which a transparent protective film is formed on at least one surface of a polarizer via an adhesive layer and an easily bonding layer in this order, wherein the adhesive layer is a curable component containing an N-substituted amide monomer having a hydroxyl group. It is formed by the active energy ray hardening-type adhesive agent which contains as an adhesive, and an easily bonding layer is at least 1 sort (s) chosen from acryloyl group, methacryloyl group, a vinyl group, and a mercapto group with respect to 100 weight part of polymer resins. It is formed of the polymer resin composition containing 3-30 weight part of organosilane compounds which have a functional group of the polarizing plate characterized by the above-mentioned.

Description

Polarizing plate, its manufacturing method, optical film, and image display apparatus {POLARIZING PLATE, MANUFACTURING THEREOF, OPTICAL FILM AND IMAGE DISPLAY}

The present invention relates to a polarizing plate and a manufacturing method thereof. The said polarizing plate can form image display apparatuses, such as a liquid crystal display device (LCD), an organic electroluminescence display, a CRT, a PDP, independently or as an optical film which laminated | stacked this.

Liquid crystal displays are rapidly expanding into markets such as watches, mobile phones, PDAs, notebook PCs, PC monitors, DVD players, and TVs. A liquid crystal display device visualizes the polarization state by switching of a liquid crystal, and a polarizer is used from the display principle. In particular, in applications such as TVs, higher luminance, higher contrast, and wider viewing angles are increasingly required, and higher transmittance, higher polarization, and higher color reproducibility are also required in polarizing plates.

As a polarizer, since the iodine type polarizer of the structure which makes iodine adsorb | suck to polyvinyl alcohol, and is extended | stretched has high transmittance | permeability and high polarization degree, it is widely used as a most common polarizer. Generally, the polarizing plate adhere | attached the transparent protective film with the so-called aqueous adhesive which melt | dissolved the polyvinyl alcohol-type material in water on both surfaces of a polarizer (patent document 1, patent document 2). As the transparent protective film, triacetyl cellulose having high moisture permeability and the like are used.

However, when manufacturing a polarizing plate as mentioned above, when using an aqueous adhesive like a polyvinyl alcohol-type adhesive agent, after attaching a polarizer and a transparent protective film, a drying process is needed. The presence of a drying process in the manufacturing process of the polarizing plate is not preferable to improve the productivity of the polarizing plate.

In addition, in the case of using an aqueous adhesive (so-called wet lamination), in order to increase the adhesiveness with the adhesive, unless the moisture content of the polarizer is relatively high (usually, the moisture content of the polarizer is about 30%), the adhesion by the aqueous adhesive It is not possible to obtain a polarizing plate having good properties. However, the polarizing plate obtained in this way has a problem that a large dimension change is carried out at high temperature, high temperature, and high humidity. On the other hand, in order to suppress the said dimensional change, the moisture content of a polarizer can be reduced or a transparent protective film with low water vapor transmission rate can be used. However, when such a polarizer and a transparent protective film are attached using an aqueous adhesive, the efficiency in the drying process, the polarization characteristics are inferior, or an appearance problem occurs, so that a practically useful polarizing plate cannot be obtained.

In addition, as represented by TV in particular, as the large screen of an image display apparatus advances in recent years, the enlargement of a polarizing plate becomes also very important from the viewpoint of productivity and cost (an increase in yield and the number of acquisitions). However, in the polarizing plate using the above-mentioned water-based adhesive, there is a problem that the so-called light omission (non-uniformity) that the polarizing plate causes a dimensional change due to the heat of the backlight and becomes uneven and that the black display appears white on a part of the whole screen is remarkable. have.

For the same reason as described above, it has been proposed to use an active energy ray-curable (particularly ultraviolet-curable) adhesive instead of an aqueous adhesive. For example, an ultraviolet curable adhesive having an acrylic or methacrylic monomer as a diluent has been proposed to an acrylic oligomer such as epoxy acrylate, urethane acrylate, polyester acrylate, etc. (patent document 3).

The performance required for a polarizing plate is becoming strict, and also when using for an active energy ray hardening-type adhesive agent, the improvement of the adhesiveness of a polarizer and a transparent protective film is calculated | required.

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-220732

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

Patent Document 3: Japanese Patent Application Laid-Open No. 61-246719

An object of the present invention is to provide a polarizing plate to which a polarizer and a transparent protective film are attached by an active energy ray-curable adhesive, and which has good adhesiveness and a method for producing the same.

Moreover, an object of this invention is to provide the optical film which laminated | stacked the said polarizing plate, Furthermore, to provide image display apparatuses, such as a liquid crystal display device using the said polarizing plate and an optical film.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, the present inventors discovered that it can achieve the said objective by the polarizing plate shown below and its manufacturing method, and came to complete this invention.

That is, this invention is a polarizing plate in which the transparent protective film is formed in this order through the adhesive bond layer and the easily bonding layer in at least one surface of a polarizer,

The adhesive layer is formed of an active energy ray curable adhesive containing an N-substituted amide monomer having a hydroxyl group as a curable component,

In addition, 3-30 weight part of organosilane compounds which have an at least 1 sort (s) of functional group out of acryloyl group, a methacryloyl group, a vinyl group, and a mercapto group with respect to 100 weight part of polymer resins. It is formed with the polymer resin composition containing, It is related with the polarizing plate characterized by the above-mentioned.

In the said polarizing plate, it is preferable that the polymer resin which forms an easily bonding layer has a polyester skeleton.

In the polarizing plate, as a curable component, a general formula (1): CH ₂ = C (R ¹ ) -CONR ² (R ³ ) (R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrogen atom or a mercap) An alkyl group having 1 to 4 carbon atoms or a branched chain which may have an earth, amino or quaternary ammonium group, and R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or a branched chain. Except when R ² and R ³ are hydrogen atoms at the same time, or R ² and R ³ are bonded to each other to form a 5-membered ring or a 6-membered ring which may contain an oxygen atom. Amide monomers can be used.

In the polarizing plate, the active energy ray-curable adhesive is preferably an electron beam-curable adhesive.

In the polarizing plate, at least one of cellulose resin, polycarbonate resin, cyclic polyolefin resin, polyester resin and (meth) acrylic resin is preferably used as the transparent protective film.

Moreover, this invention is a manufacturing method of the said polarizing plate in which the transparent protective film is formed in at least one surface of a polarizer through an adhesive bond layer and an easily bonding layer in this order,

With polarizer,

To a polymer resin composition containing 3 to 30 parts by weight of an organosilane compound having at least one functional group selected from acryloyl, methacryloyl, vinyl and mercapto groups based on 100 parts by weight of the polymer resin. The transparent protective film in which the easily bonding layer formed by

Attaching process by active energy ray hardening-type adhesive agent which contains N-substituted amide monomer which has a hydroxyl group as a curable component so that the easily bonding layer formed in the said transparent protective film may face a polarizer,

Next, it is related with the manufacturing method of the polarizing plate which has a process of hardening the said adhesive agent by active energy ray irradiation, and forming an adhesive bond layer.

Moreover, this invention relates to the optical film characterized by the lamination | stacking of at least 1 piece of the said polarizing plates.

Moreover, this invention relates to the image display apparatus characterized by the said polarizing plate or the said optical film being used.

In the polarizing plate of this invention, an active energy ray hardening-type adhesive agent is used as an adhesive agent for attachment of a polarizer and a transparent protective film. Since the active energy ray-curable adhesive is a solvent-free adhesive, the polarizer and the transparent protective film can be attached without performing a drying step like the aqueous adhesive. Moreover, in an active energy ray hardening-type adhesive agent, since an adhesive bond layer is formed by irradiation of an active energy ray, high speed production is possible compared with an aqueous adhesive agent.

As an active energy ray hardening-type adhesive agent used for the said polarizing plate, an electron beam hardening-type adhesive agent is preferable. The electron beam curable adhesive is more productive than the ultraviolet curable adhesive, and by using an electron beam (that is, dry lamination) as a curing method of the adhesive used to attach the polarizer and the transparent protective film, a heating step such as the ultraviolet curing method becomes unnecessary, Productivity can be very high. Moreover, durability of a polarizing plate can be improved compared with an ultraviolet curable adhesive by using an electron beam curable adhesive.

On the other hand, when using an active energy ray hardening-type adhesive agent as an adhesive agent used for adhesion | attachment of a polarizer and a transparent protective film as mentioned above, the adhesive force between a polarizer and a transparent protective film may be insufficient. If the adhesive force is insufficient, there is a risk of causing the lamination of the polarizer and the transparent protective film when the polarizing plate is reworked by mispositioning the polarizing plate or the like. In this invention, adhesive force is improved by forming an easily bonding layer between the transparent protective film and the adhesive bond layer formed by the active energy ray hardening-type adhesive agent which contains the N-substituted amide type monomer which has a hydroxyl group as a curable component. The delamination in the rework can be suppressed. In this invention, since an adhesive bond layer is formed by the said active energy ray hardening-type adhesive agent, a specific organosilane compound is added to the easily bonding layer in addition to the polymer resin used as a base so that adhesive force may be improved more with respect to the said adhesive agent. Doing. That is, in this invention, especially the organosilane compound, by using the thing which has at least 1 sort (s) of functional group among what is chosen from acryloyl group, methacryloyl group, a vinyl group, and a mercapto group, the adhesive force by an easily bonding layer Is improving.

In the present invention, as described above, an N-substituted amide monomer having a hydroxyl group is used as the curable component of the active energy ray-curable adhesive. The said monomer is preferable at an adhesive point, and it is especially suitable as an electron beam curable adhesive. For example, even when a low moisture content polarizer is used and also when a material with low moisture permeability is used as the transparent protective film, the electron beam curable adhesive shows good adhesion to these, and as a result, a polarizing plate having good dimensional stability. Is obtained.

When using the said curable component, since a polarizing plate with a small dimensional change can be manufactured, it can respond easily also to enlargement of a polarizing plate, and can suppress a production cost from a viewpoint of a yield and the acquisition number. Moreover, since the polarizing plate obtained by this invention has good dimensional stability, it can suppress generation | occurrence | production of the nonuniformity of the image display apparatus by the external heat of a backlight.

As for the polarizing plate of this invention, the transparent protective film is formed through the adhesive bond layer on at least one surface of a polarizer. An active energy ray hardening-type adhesive agent is used for formation of the said adhesive bond layer. The active energy ray curable adhesive contains an N-substituted amide monomer having a hydroxyl group as the curable component. The hydroxyl group may have at least 1 substituent couple | bonded with the nitrogen atom (N) which forms an amide group, and may have 2 or more. As the N-substituted amide monomer having a hydroxyl group, both monofunctional and bifunctional or higher functional groups can be used. Moreover, the N-substituted amide monomer which has a hydroxyl group can select 1 type, or can use it in combination of 2 or more type.

The N-substituted amide monomer having a hydroxyl group exhibits good adhesion to a low moisture content polarizer and a transparent protective film using a material having a low moisture permeability. In particular, the following monomers exhibit good adhesion. For example, as an N-substituted amide monomer, N-hydroxyethyl (meth) acrylamide, N- (2,2-dimethoxy-1-hydroxyethyl)-(meth) acrylamide, N-hydride Oxymethyl (meth) acrylamide, p-hydroxyphenyl (meth) acrylamide, N, N '-(1,2-dihydroxyethylene) bis (meth) acrylamide, etc. are mentioned. Among these, N-hydroxyethyl (meth) acrylamide is preferable. In addition, (meth) acrylamide means an acrylamide group and / or a methacrylamide group. In the present invention, (meth) has the same meaning as described above.

Moreover, as a curable component, in addition to the N-substituted amide monomer which has a hydroxyl group, another monomer can be contained. As another monomer which can be used as a curable component, the compound which has a (meth) acryloyl group, and the compound which has a vinyl group is mentioned. The other monomer used as these curable components can use either monofunction or bifunctional or more. These curable components can be used 1 type or in combination of 2 or more types.

As another monomer used as the curable component, for example, N-substituted amide monomers other than N-substituted amide monomers having a hydroxyl group are preferably used. The N-substituted amide monomers are represented by the general formula (1): CH ₂ = C (R ¹ ) -CONR ² (R ³ ) (R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or a mercapto group, A C1-C4 linear or branched alkyl group which may have an amino group or a quaternary ammonium group, R <^3> represents a hydrogen atom or a C1-C4 linear or branched alkyl group, R <^2> And when R ³ is a hydrogen atom at the same time, or R ² and R ³ are bonded to each other to form a 5- or 6-membered ring which may contain an oxygen atom. As a C1-C4 linear or branched alkyl group in R <^2> or R <^3> in the said General formula (1), a methyl group, an ethyl group, isopropyl group, t-butyl group etc. are mentioned, for example. Examples of the alkyl group having an amino group include an aminomethyl group and an aminoethyl group. Moreover, when R <^2> , R <^3> combines and forms the 5-membered ring or 6-membered ring which may contain an oxygen atom, it has a heterocyclic ring which has nitrogen. As said heterocyclic ring, a morpholine ring, a piperidine ring, a pyrrolidine ring, a piperazine ring, etc. are mentioned.

As a specific example of the said N-substituted amide monomer, For example, N-methyl (meth) acrylamide, N, N- dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N -Isopropylacrylamide, N-butyl (meth) acrylamide, N-hexyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylol-N-propane (meth) acrylamide, aminomethyl (Meth) acrylamide, aminoethyl (meth) acrylamide, mercaptomethyl (meth) acrylamide, mercaptoethyl (meth) acrylamide, and the like. Moreover, as a heterocyclic containing monomer which has a heterocyclic ring, for example, N-acryloyl morpholine, N-acryloyl piperidine, N-methacryloyl piperidine, N-acryloylpyrrolidine, etc. Can be mentioned. These N-substituted amide monomers can be used individually by 1 type or in combination of 2 or more type.

When using in combination N-substituted amide monomer which has a hydroxyl group as a curable component, and N-substituted amide monomer represented by the said General formula (1), it is N- in terms of durability, coatability, and adhesiveness. Preference is given to a combination of hydroxyethyl (meth) acrylamide and N-acryloyl morpholine. In the combination, the ratio of N-hydroxyethyl (meth) acrylamide to the total amount of N-hydroxyethyl (meth) acrylamide and N-acryloyl morpholine is preferably 40% by weight or more. It is preferable to obtain. 40-95 weight% is more preferable, and, as for the said ratio, it is still more preferable that it is 60-90 weight%.

Moreover, as a monomer which can be used together with the N-substituted amide monomer which has a hydroxyl group as a curable component, as a compound which has a (meth) acryloyl group in addition to the above, For example, various epoxy (meth) acrylates, Urethane (meth) acrylate, polyester (meth) acrylate, various (meth) acrylate type monomers, etc. are mentioned. Among these, epoxy (meth) acrylate, especially monofunctional (meth) acrylate which has an aromatic ring and a hydroxyl group, is used preferably.

As the monofunctional (meth) acrylate having an aromatic ring and a hydroxyl group, various monofunctional (meth) acrylates having an aromatic ring and a hydroxyl group can be used. Although the hydroxyl group may exist as a substituent of an aromatic ring, in this invention, it is preferable to exist as an organic group (hydrocarbon group, especially what couple | bonded with the alkylene group) which couple | bonds an aromatic ring and a (meth) acrylate.

As monofunctional (meth) acrylate which has the said aromatic ring and a hydroxyl group, the reactant of the monofunctional epoxy compound which has an aromatic ring, and (meth) acrylic acid is mentioned, for example. As a monofunctional epoxy compound which has an aromatic ring, phenyl glycidyl ether, t-butylphenyl glycidyl ether, phenyl polyethyleneglycol glycidyl ether, etc. are mentioned, for example. As a specific example of monofunctional (meth) acrylate which has an aromatic ring and a hydroxyl group, For example, 2-hydroxy-3- phenoxypropyl (meth) acrylate, 2-hydroxy-3-t-butyl Phenoxypropyl (meth) acrylate, 2-hydroxy-3-phenyl polyethylene glycol propyl (meth) acrylate, etc. are mentioned.

Moreover, a carboxyl group monomer is mentioned as a compound which has a (meth) acryloyl group. A carboxyl group monomer is also preferable at an adhesive point. As a carboxyl monomer, (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, etc. are mentioned, for example. Among these, acrylic acid is preferable.

As a compound which has a (meth) acryloyl group other than the above, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isooctyl Alkyl (meth) acrylates having 1 to 12 carbon atoms such as (meth) acrylate, isononyl (meth) acrylate, and lauryl (meth) acrylate; Alkoxy (meth) acrylate alkyl monomers, such as methoxy ethyl (meth) acrylate and ethoxy ethyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, Hydroxyl group-containing monomers such as (meth) acrylic acid 10-hydroxydecyl, (meth) acrylic acid 12-hydroxylauryl and (4-hydroxymethylcyclohexyl) -methylacrylate; Acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; Caprolactone adducts of acrylic acid; Contains sulfonic acid groups, such as styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamide propanesulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxy naphthalene sulfonic acid Monomers; Phosphoric acid group containing monomers, such as 2-hydroxyethyl acryloyl phosphate, etc. are mentioned. Moreover, (meth) acrylamide; Maleimide, N-cyclohexyl maleimide, N-phenylmaleimide, etc .; Aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate, 3- (3-pyridylyl) propyl (meth) acrylate (Meth) acrylic-acid alkylaminoalkyl monomers, such as these; Such as N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, and N- (meth) acryloyl-8-oxyoctamethylene succinimide Nitrogen containing monomers, such as a succinimide type monomer, are mentioned.

As mentioned above, although the N-substituted amide monomer which has a hydroxyl group is used as a curable component in an active energy ray hardening-type adhesive agent, N-substituted amide represented by the said General formula (1) as a monomer used together with this System monomers are preferred. Moreover, when using together the monofunctional (meth) acrylate which has an aromatic ring and a hydroxyl group as a curable component, the ratio of the N-substituted amide monomer which has a hydroxyl group is 40 weight% or more, Furthermore, 50 weight% or more And 60 weight% or more, Furthermore, it is preferable to set it as 70 weight% or more, especially 80 weight% or more.

As the curable component, a bifunctional or higher curable component can be used. As a bifunctional or more curable component, bifunctional or more than (meth) acrylate, especially bifunctional or more than epoxy (meth) acrylate are preferable. The bifunctional or more functional epoxy (meth) acrylate is obtained by reaction of a polyfunctional epoxy compound and (meth) acrylic acid. A polyfunctional epoxy compound can illustrate various things. As a polyfunctional epoxy compound, an aromatic epoxy resin, an alicyclic epoxy resin, and an aliphatic epoxy resin are mentioned, for example.

As an aromatic epoxy resin, For example, Bisphenol-type epoxy resins, such as the diglycidyl ether of bisphenol A, the diglycidyl ether of bisphenol F, and the diglycidyl ether of bisphenol S; Novolak-type epoxy resins, such as a phenol novolak epoxy resin, a cresol novolak epoxy resin, and hydroxy benzaldehyde phenol novolak epoxy resin; And polyfunctional epoxy resins such as glycidyl ether of tetrahydroxyphenylmethane, glycidyl ether of tetrahydroxybenzophenone, and epoxidized polyvinylphenol.

As an alicyclic epoxy resin, epoxy resins, such as the hydrogenated substance of the said aromatic epoxy resin, a cyclohexane system, a cyclohexyl methyl ester system, a cyclohexyl methyl ether system, a spiro system, and a tricyclodecane system, are mentioned.

As an aliphatic epoxy resin, the polyglycidyl ether of an aliphatic polyhydric alcohol or its alkylene oxide adduct is mentioned. Examples thereof include diglycidyl ether of 1,4-butanediol, diglycidyl ether of 1,6-hexanediol, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, and diglycol of polyethylene glycol. Polyether polyols obtained by adding one or two or more alkylene oxides (ethylene oxide or propylene oxide) to aliphatic polyhydric alcohols such as cylyl ether, diglycidyl ether of propylene glycol, ethylene glycol, propylene glycol, and glycerin Polyglycidyl ether etc. are mentioned.

The epoxy equivalent of the said epoxy resin is 30-3000 g / equivalent normally, Preferably it is the range of 50-1500 g / equivalent.

As for the said bifunctional or more epoxy (meth) acrylate, the epoxy (meth) acrylate of an aliphatic epoxy resin is preferable. In particular, the epoxy (meth) acrylate of a bifunctional aliphatic epoxy resin is preferable.

Although the active energy ray hardening-type adhesive agent of this invention contains a curable component, you may add an additive suitably to the said component as needed. An active energy ray hardening-type adhesive agent can be used with the aspect of an electron beam hardening type and an ultraviolet curable type. When using the said adhesive agent by electron beam curing type, it is not necessary in particular to contain a photoinitiator in the said adhesive agent, but when using by an ultraviolet curing type, a photoinitiator is used. The usage-amount of a photoinitiator is about 0.1-10 weight part normally per 100 weight part of curable components, Preferably it is 0.5-3 weight part.

Examples of the additive include a sensitizer which increases the curing rate and sensitivity by an electron beam such as a carbonyl compound, an adhesion promoter represented by a silane coupling agent or ethylene oxide, an additive which improves the wettability with a transparent protective film, and an acryl. Representatives such as hydroxy compounds or hydrocarbon-based (natural, synthetic resin), additives to improve mechanical strength and processability, UV absorbers, antioxidants, dyes, processing aids, ion traps, antioxidants, tackifiers, fillers ( Metal compound fillers), plasticizers, leveling agents, foaming inhibitors, antistatic agents and the like.

In the polarizing plate of the present invention, a polarizer and a transparent protective film are formed via an adhesive layer, but have an easily bonding layer between the transparent protective film and the adhesive layer. The easily bonding layer is formed of a polymer resin composition containing an organosilane compound having at least one functional group selected from acryloyl group, methacryloyl group, vinyl group and mercapto group and a polymer resin.

As a polymer resin which forms an easily bonding layer, it is various resin which has a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone type, a polyamide skeleton, a polyimide skeleton, a polyvinyl alcohol skeleton, etc., for example. Can be used. Although these polymer resins can be used individually by 1 type or in combination of 2 or more types, Among these, resin which has a polyester skeleton is preferable at the point of the improvement effect of an adhesive force. The form of the said polymer resin may be either an aqueous system or a solvent system.

As an organosilane compound which has the said functional group, the silane coupling agent which has the said functional group is mentioned, for example. As an organosilane compound which has an acryloyl group, 3-acryloxypropyl trimethoxysilane, 3-acryloxypropyl triethoxysilane, etc. are mentioned, for example, The organosilane which has a methacryloyl group is mentioned. Examples of the compound include 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, and 3-methacryloxypropylmethyldiethoxy. Silane etc. are mentioned, As an organosilane compound which has a vinyl group, For example, vinyltrimethoxysilane, allyl triethoxysilane, allyl trimethoxysilane, p-styryl trimethoxysilane, p- Styryl triethoxysilane etc. are mentioned, As an organosilane compound which has a mercapto group etc., for example, 3-mercaptopropyl methyldimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3 -Mercaptopropyl triethoxysilane, etc. are mentioned There.

Although the organosilane compound which has the said functional group can improve adhesive force by mix | blending with the said polymer resin, In order to improve the adhesive force more, the organosilane compound which has the said functional group is added with respect to 100 weight part of said polymer resins (solid content). 3-30 weight part is mix | blended. It is further more preferable that the compounding ratio of the organosilane compound which has the said functional group is 5-25 weight part and 7-15 weight part with respect to 100 weight part of said polymer resins (solid content).

Moreover, you may add another additive to formation of an easily bonding layer. Specifically, you may use stabilizers, such as a tackifier, a ultraviolet absorber, antioxidant, and a heat resistant stabilizer. Moreover, it can be crosslinking components, such as methylol compounds, such as oxazoline, a boric acid, and a trimethylol melamine, a carbodiimide, an isocyanate compound, the organosilane compound which does not have the said functional group, or has functional groups other than the said functional group Organosilane compound (silane coupling agents, such as an epoxy group containing silane coupling agent, an amino group containing silane coupling agent, and an isocyanate group containing silane coupling agent) can also be mix | blended. In addition, although an additive (or crosslinking component) other than the organosilane compound having the functional group is used alone, the adhesive force cannot be sufficiently improved, but these additives do not prevent the combination with the organosilane compound having the functional group. In addition, adhesiveness can be improved further by using together. In addition, when using additives other than the organosilane compound which has the said functional group, the compounding ratio is 50 weight part or less with respect to 100 weight part of said polymer resins, Furthermore, it is 1-40 weight part, Especially 5-30 weight part It is preferable.

The easily bonding layer is usually formed in advance in the transparent protective film, and the easily bonding layer side and the polarizer of the said transparent protective film are affixed with an adhesive bond layer. Formation of an easily bonding layer prepares the polymer resin composition (forming material of an easily bonding layer) containing the said polymer resin and the organosilane compound which has the said functional group, and forms this formation material by a well-known technique on a transparent protective film. It is performed by coating and drying. The formation material of an easily bonding layer is normally adjusted as a solution diluted to an appropriate density | concentration in consideration of the thickness after drying, the smoothness of coating, etc. The thickness after drying of an easily bonding layer becomes like this. Preferably it is 0.01-5 micrometers, More preferably, it is 0.02-2 micrometers, Especially preferably, it is 0.05-1 micrometer. In addition, although the easily bonding layer can be formed in multiple layers, also in this case, it is preferable to make the total thickness of an easily bonding layer into the said range. Moreover, before and after coating an easily bonding layer to a transparent protective film, a transparent protective film can be extended | stretched.

The polarizer is formed of polyvinyl alcohol-based resin. The polarizer is one obtained by dyeing a polyvinyl alcohol resin film with a dichroic substance (typically iodine, dichroic dye) and uniaxially stretching it. Preferably the polymerization degree of the polyvinyl alcohol-type resin which comprises a polyvinyl alcohol-type resin film is 100-5000, More preferably, it is 1400-4000. If the degree of polymerization is too low, the stretching is likely to be interrupted at the time of carrying out a predetermined stretching, and if the degree of polymerization is too high, tension is abnormally required at the time of stretching and mechanical stretching may not be possible.

The polyvinyl alcohol-based resin film constituting the polarizer can be molded by any suitable method (e.g., casting method, casting method, extrusion method for casting film into a solution in which resin is dissolved in water or an organic solvent). Although the thickness of a polarizer is suitably set according to the objective and the use of LCD which a polarizing plate is used, it is about 5-80 micrometers normally.

As a manufacturing method of a polarizer, arbitrary appropriate methods are employ | adopted according to the objective, material used, conditions, etc .. For example, the method of providing the said polyvinyl alcohol-type resin film to a series of manufacturing processes normally including a swelling, dyeing, crosslinking, extending | stretching, water washing, and a drying process is employ | adopted. In each processing process except a drying process, it processes by immersing a polyvinyl alcohol-type resin film in the liquid containing the solution used for each process. The order, frequency, and presence of each treatment of swelling, dyeing, crosslinking, stretching, washing with water and drying can be appropriately set according to the purpose, materials used and conditions. For example, several treatments may be performed simultaneously in one process, and swelling treatment, dyeing treatment and crosslinking treatment may be performed simultaneously. For example, it can be preferably employed to carry out the crosslinking treatment before and after the stretching treatment. For example, the water washing treatment may be performed after all the treatments or only after the specific treatment.

The swelling step is typically performed by immersing the polyvinyl alcohol-based resin film in a treatment bath filled with water. By this treatment, the contamination of the surface of the polyvinyl alcohol-based resin film and the blocking agent are washed, and the non-uniformity such as dyeing unevenness can be prevented by swelling the polyvinyl alcohol-based resin film. Glycerine, potassium iodide, etc. are added suitably to a swelling bath. The temperature of the swelling bath is usually about 20 to 60 ° C, and the immersion time in the swelling bath is usually about 0.1 to 10 minutes.

The dyeing step is typically performed by immersing the polyvinyl alcohol-based resin film in a treatment bath containing dichroic substances such as iodine. As a solvent used for the solution of the dyeing bath, water is generally used, but an appropriate amount of an organic solvent having compatibility with water may be added. Dichroic substance is normally used in the ratio of 0.1-1 weight part with respect to 100 weight part of solvents. In the case of using iodine as the dichroic substance, the solution of the dyeing bath preferably further contains an auxiliary such as iodide. This is because the dyeing efficiency is improved. The adjuvant is preferably used in an amount of 0.02 to 20 parts by weight, more preferably 2 to 10 parts by weight with respect to 100 parts by weight of the solvent. Specific examples of iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, titanium iodide, and the like. The temperature of a dyeing bath is about 20-70 degreeC normally, and the immersion time to a dyeing bath is about 1 to 20 minutes normally.

A crosslinking process is typically performed by immersing the said dyed polyvinyl alcohol-type resin film in the process bath containing a crosslinking agent. Arbitrary suitable crosslinking agents are employ | adopted as a crosslinking agent. As a specific example of a crosslinking agent, boron compounds, such as a boric acid and borax, glyoxal, glutaraldehyde, etc. are mentioned. These are used individually or in combination. As a solvent used for the solution of a crosslinking bath, although water is generally used, the appropriate amount of the organic solvent which is compatible with water may be added. A crosslinking agent is normally used in 1-10 weight part with respect to 100 weight part of solvents. When the concentration of the crosslinking agent is less than 1 part by weight, sufficient optical properties cannot be obtained. When the density | concentration of a crosslinking agent exceeds 10 weight part, the stress which arises in a film at the time of extending | stretching may become large, and the polarizing plate obtained may shrink | contract. It is preferable that the solution of a crosslinking bath further contains adjuvant, such as iodide. It is because it is easy to obtain a uniform characteristic in surface. The concentration of the adjuvant is preferably 0.05 to 15% by weight, more preferably 0.5 to 8% by weight. Specific examples of the iodide are the same as in the dyeing process. The temperature of the crosslinking bath is usually about 20 to 70 ° C, preferably 40 to 60 ° C. Immersion time to a crosslinking bath is about 1 second-about 15 minutes normally, Preferably they are 5 second-10 minutes.

The stretching step may be performed at any stage as described above. Specifically, it may be carried out after the dyeing treatment, may be carried out before the dyeing treatment, may be performed simultaneously with the swelling treatment, the dyeing treatment and the crosslinking treatment, or may be carried out after the crosslinking treatment. The cumulative stretching ratio of the polyvinyl alcohol-based resin film is usually 5 times or more. Preferably it is 5 to 7 times, More preferably, it is 5 to 6.5 times. When the cumulative draw ratio is less than 5 times, it becomes difficult to obtain a polarizing plate with high polarization degree. When the cumulative stretching ratio exceeds 7 times, the polyvinyl alcohol-based resin film may be easily broken. Arbitrary appropriate methods are employ | adopted as a specific method of extending | stretching. For example, when the wet stretching method is adopted, the polyvinyl alcohol-based resin film is stretched at a predetermined magnification in the treatment bath. As a solution of an extending | stretching bath, the solution which added the compound of various metal salts, iodine, boron, or zinc in solvent, such as water or an organic solvent (for example, ethanol), is used preferably.

The washing process is typically performed by immersing the polyvinyl alcohol-based resin film subjected to the various treatments in a treatment bath. The unnecessary residue of a polyvinyl alcohol-type resin film can be wash | cleaned by the water washing process. The water washing bath may be pure water or an aqueous solution of iodide (for example, potassium iodide, sodium iodide, etc.) may be used. The concentration of the iodide aqueous solution is preferably 0.1 to 10% by weight. You may add adjuvant, such as zinc sulfate and zinc chloride, to an iodide aqueous solution. The temperature of the water washing bath is preferably 10 to 60 ° C, more preferably 30 to 40 ° C. Immersion time is from 1 second to 1 minute. The water washing step may be performed only once or may be performed multiple times as necessary. In the case of carrying out a plurality of times, the kind and concentration of the additive contained in the water washing bath used for each treatment are appropriately adjusted. For example, the washing step is a step of immersing the polyvinyl alcohol-based resin film subjected to the above various treatments in an aqueous solution of potassium iodide (0.1 to 10% by weight, 10 to 60 ° C) for 1 second to 1 minute and rinsing with pure water. Process. Moreover, in the water washing process, in order to improve the surface modification of a polarizer and the drying efficiency of a polarizer, you may add the organic solvent (for example, ethanol etc.) which is compatible with water suitably.

The drying process may employ any suitable method (eg, natural drying, blowing drying, heating drying). For example, the drying temperature in the case of heat drying is about 20-80 degreeC normally, and a drying time is about 1 to 10 minutes normally. A polarizer is obtained as mentioned above.

The water content of the polarizer used in this invention becomes like this. Preferably it is 20 weight% or less, More preferably, it is 0-15 weight%, More preferably, it is 1-15 weight%. When moisture content is larger than 20 weight%, there exists a possibility that the dimension change of the obtained polarizing plate may become large, and the problem that the dimensional change in high temperature or under high temperature, high humidity becomes large may arise.

What is necessary is just to adjust the moisture content of the polarizer of this invention by arbitrary appropriate methods. For example, the method of controlling by adjusting the conditions of the drying process in the manufacturing process of a polarizer is mentioned.

The moisture content of a polarizer is measured by the following method. That is, the polarizer was cut into the size of 100x10 mm, and the initial weight of this sample was measured. Then, this sample was dried at 120 degreeC for 2 hours, dry weight was measured, and moisture content was measured by the following formula. Moisture content (% by weight) = {(initial weight-dry weight) / initial weight} × 100. The weight is measured three times each, and the average value is used.

As a material which comprises a transparent protective film, the thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, etc. is used, for example. Specific examples of such thermoplastic resins include polyester resins such as cellulose resins such as triacetyl cellulose, polyethylene terephthalate, polyethylene butyrate and polyethylene naphthalate, polyether sulfone resins, polysulfone resins, polycarbonate resins, and polyamides. Resins, polyimide resins, polyolefin resins, (meth) acrylic resins, cyclic polyolefin resins (norbornene-based resins), polyallylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof. In addition, a transparent protective film is attached to one side of the polarizer by an adhesive layer. On the other side, a thermosetting resin such as (meth) acrylic, urethane, acrylic urethane, epoxy, silicone, or ultraviolet curable resin can be used as the transparent protective film. Can be. The transparent protective film may contain one or more types of appropriate additives arbitrarily. As an additive, a ultraviolet absorber, antioxidant, a lubricating agent, a plasticizer, a mold release agent, a coloring agent, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a coloring agent, etc. are mentioned, for example. Content of the said thermoplastic resin in a transparent protective film becomes like this. Preferably it is 50-100 weight%, More preferably, it is 50-99 weight%, More preferably, it is 60-98 weight%, Especially preferably, it is 70-97 weight%. When content of the said thermoplastic resin in a transparent protective film is 50 weight% or less, there exists a possibility that the high transparency etc. which a thermoplastic resin originally has may not be fully expressed.

Moreover, as a transparent protective film, the polymer film of Unexamined-Japanese-Patent No. 2001-343529 (WO01 / 37007), for example, (A) thermoplastic resin which has a substituted and / or unsubstituted imide group in a side chain, ( B) The resin composition containing the thermoplastic resin which has a substituted and / or unsubstituted phenyl and a nitrile group in a side chain is mentioned. As a specific example, the film of the resin composition containing the alternating copolymer which consists of isobutylene and N-methyl maleimide, and an acrylonitrile styrene copolymer is mentioned. As a film, the film which consists of a mixed extrusion product of a resin composition, etc. can be used. Since these films have a small phase difference and a small photoelastic coefficient, problems such as nonuniformity due to deformation of the polarizing plate can be solved, and the moisture permeability is small, so the humidification durability is excellent.

Although the thickness of a transparent protective film can be suitably determined, it is about 1-500 micrometers generally from the points of workability, thinness, etc., such as strength and handleability. 1-300 micrometers is especially preferable, and 5-200 micrometers is more preferable. A transparent protective film is especially preferable when it is 5-150 micrometers.

In addition, when forming a transparent protective film on both sides of a polarizer, you may use the protective film which consists of the same polymer material in the front and back, and may use the protective film which consists of different polymer materials.

As the transparent protective film of the present invention, it is preferable to use at least one selected from a cellulose resin, a polycarbonate resin, a cyclic polyolefin resin, a polyester resin, and a (meth) acrylic resin. The adhesive agent for electron beam curable polarizing plates of this invention shows preferable adhesiveness with respect to the said various transparent protective films. In particular, the adhesive agent for electron beam hardening type polarizing plates of this invention shows favorable adhesiveness also with respect to the acrylic resin which was difficult to satisfy adhesiveness.

Cellulose resins are esters of cellulose and fatty acids. Specific examples of such cellulose ester-based resins include cellulose triacetate, cellulose diacetate, cellulose tripropionate, cellulose dipropionate, and the like. Among these, cellulose triacetate is particularly preferable. Cellulose triacetate is commercially available in many products, and is advantageous in terms of availability and cost. Examples of commercially available products of cellulose triacetate include trade names "UV-50", "UV-80", "SH-80", "TD-80U", "TD-TAC" and "UZ-TAC" manufactured by Fuji Photo Film Co., Ltd. And "KC series" manufactured by Konica Corporation. Generally, these cellulose triacetates have an in-plane retardation (Re) of almost zero, but the thickness retardation (Rth) has a thickness of about 60 nm.

Moreover, the cellulose resin film with a small thickness direction retardation is obtained by processing the said cellulose resin, for example. For example, base films, such as polyethylene terephthalate, polypropylene, and stainless steel, which are coated with solvents such as cyclopentanone and methyl ethyl ketone, are attached to a common cellulose-based film and dried by heating (for example, 3 to 10 at 80 to 150 ° C). After a minute), and the method of peeling a base film; A solution obtained by dissolving norbornene-based resin and (meth) acrylic resin in a solvent such as cyclopentanone and methyl ethyl ketone is coated on a common cellulose resin film and dried by heating (for example, at about 80 to 150 ° C. for about 3 to 10 minutes). After making it, the method of peeling a coating film, etc. are mentioned.

Moreover, as a cellulose resin film with a small thickness direction retardation, the fatty acid cellulose resin film which controlled fat substitution degree can be used. In the triacetyl cellulose generally used, although acetic acid substitution degree is about 2.8, Preferably, Rth can be made small by controlling acetic acid substitution degree to 1.8-2.7. Rth can be controlled small by adding plasticizers, such as dibutyl phthalate, p-toluenesulfonanilide, and acetyl triethyl citrate, to the said fatty acid substituted cellulose resin. The amount of the plasticizer added is preferably 40 parts by weight or less, more preferably 1 to 20 parts by weight, still more preferably 1 to 15 parts by weight based on 100 parts by weight of fatty acid cellulose resin.

As a specific example of cyclic polyolefin resin, Preferably it is norbornene-type resin. Cyclic olefin resin is a general term for resin which superpose | polymerizes a cyclic olefin as a polymerization unit, For example, Unexamined-Japanese-Patent No. 1-240517, Unexamined-Japanese-Patent No. 3-14882, Unexamined-Japanese-Patent No. 3 The resin described in -122137 etc. is mentioned. Specific examples include ring-opening (co) polymers of cyclic olefins, addition polymers of cyclic olefins, α-olefins such as cyclic olefins, ethylene and propylene, and copolymers thereof (typically random copolymers), and these Graft copolymers modified with unsaturated carboxylic acids and derivatives thereof, and their hydrides. As a specific example of a cyclic olefin, a norbornene-type monomer is mentioned.

Various products are commercially available as the cyclic polyolefin resin. As a specific example, the brand name "Xeonex", "Xeonoa" made by Japan Xeon Corporation, a brand name "Aton" made by JSR Corporation, a brand name "Topas" made by TICONA company, a brand name "APEL" made by Mitsui Chemicals, Inc. are mentioned Can be.

As (meth) acrylic-type resin, Tg (glass transition temperature) becomes like this. Preferably it is 115 degreeC or more, More preferably, it is 120 degreeC or more, More preferably, it is 125 degreeC or more, Especially preferably, it is 130 degreeC or more. When Tg is 115 degreeC or more, durability of a polarizing plate can be excellent. Although the upper limit of Tg of the said (meth) acrylic-type resin is not specifically limited, From a viewpoint of moldability etc., Preferably it is 170 degrees C or less. From (meth) acrylic-type resin, the film whose in-plane phase difference Re and thickness direction phase difference Rth are almost zero can be obtained.

As (meth) acrylic-type resin, arbitrary appropriate (meth) acrylic-type resin can be employ | adopted within the range which does not impair the effect of this invention. For example, poly (meth) acrylic acid ester, such as polymethyl methacrylate, methyl methacrylate- (meth) acrylic acid copolymer, methyl methacrylate- (meth) acrylic acid ester copolymer, methyl methacrylate-acrylate ester- (Meth) acrylic acid copolymer, methyl (meth) acrylate-styrene copolymer (such as MS resin), polymer having an alicyclic hydrocarbon group (for example, methyl methacrylate-cyclohexyl copolymer, methyl methacrylate) -Norbornel (meth) acrylate copolymer, etc.) can be mentioned. Preferably, poly (meth) acrylic-acid C1-6 alkyl, such as methyl poly (meth) acrylate, is mentioned. More preferably, methyl methacrylate type resin which has methyl methacrylate as a main component (50-100 weight%, Preferably 70-100 weight%) is mentioned.

As a specific example of (meth) acrylic-type resin, For example, Mitsubishi Rayon Co., Ltd. Acripet VH, Acripet VRL20A, (meth) acrylic-type resin which has a ring structure in the molecule | numerator of Unexamined-Japanese-Patent No. 2004-70296. And a high Tg (meth) acrylic resin system obtained by intramolecular crosslinking or intramolecular cyclization reaction.

As (meth) acrylic-type resin, you may use (meth) acrylic-type resin which has lactone ring structure. It is because it has high mechanical strength by high heat resistance, high transparency, and biaxial stretching.

As (meth) acrylic-type resin which has a lactone ring structure, Unexamined-Japanese-Patent No. 2000-230016, Unexamined-Japanese-Patent No. 2001-151814, Unexamined-Japanese-Patent No. 2002-120326, Unexamined-Japanese-Patent No. 2002-254544, Japan (Meth) acrylic-type resin which has a lactone ring structure as described in Unexamined-Japanese-Patent No. 2005-146084 etc. is mentioned.

The (meth) acrylic resin having a lactone ring structure preferably has a ring structure represented by the following General Formula (Formula 1).

In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom or an organic residue having 1 to 20 carbon atoms. In addition, the organic residue may contain the oxygen atom.

The content ratio of the lactone ring structure represented by General Formula (Formula 1) in the structure of the (meth) acrylic resin having a lactone ring structure is preferably 5 to 90% by weight, more preferably 10 to 70% by weight, still more preferably Is 10 to 60% by weight, particularly preferably 10 to 50% by weight. When the content rate of the lactone ring structure represented by General formula (Formula 1) in the structure of (meth) acrylic-type resin which has a lactone ring structure is less than 5 weight%, there exists a possibility that heat resistance, solvent resistance, and surface hardness may become inadequate. When the content rate of the lactone ring structure represented by General formula (Formula 1) in the structure of (meth) acrylic-type resin which has a lactone ring structure is more than 90 weight%, there exists a possibility that molding workability may become inadequate.

The (meth) acrylic resin having a lactone ring structure preferably has a mass average molecular weight (sometimes referred to as a weight average molecular weight), preferably 1000 to 2000000, more preferably 5000 to 1000000, still more preferably 10000 to 500000, particularly preferably Preferably 50000 to 500000. If the mass average molecular weight is out of the above range, it is not preferable in terms of molding processability.

The (meth) acrylic resin having a lactone ring structure preferably has a Tg of 115 ° C or higher, more preferably 120 ° C or higher, still more preferably 125 ° C or higher, and particularly preferably 130 ° C or higher. Since Tg is 115 degreeC or more, when it is built in a polarizing plate as a transparent protective film, it becomes excellent in durability, for example. Although the upper limit of Tg of (meth) acrylic-type resin which has the said lactone ring structure is not specifically limited, From a viewpoint of moldability etc., Preferably it is 170 degrees C or less.

The (meth) acrylic resin having a lactone ring structure is preferably the higher the total light transmittance measured by the method according to ASTM-D-1003 of the molded article obtained by injection molding, and is preferably 85% or more, more preferably Is 88% or more, more preferably 90% or more. If the total light transmittance is less than 85% on the basis of transparency, the transparency of the total light transmittance may decrease.

As for the said transparent protective film, a thing whose frontal phase difference is less than 40 nm and whose thickness direction phase difference is less than 80 nm is normally used. The front phase difference Re is represented by Re = (nx-ny) x d ,. Thickness direction retardation (Rth) is represented by Rth = (nx-nz) xd. In addition, Nz coefficient is represented by Nz = (nx-nz) / (nx-ny). [However, the refractive indices of the slow axis direction, the fast axis direction, and the thickness direction of the film are nx, ny, and nz, respectively, and d (nm) is the thickness of the film. The slow axis direction is a direction in which the refractive index in the film plane is maximized. Moreover, it is preferable that a transparent protective film does not have coloring as much as possible. The protective film whose retardation value of the thickness direction is -90 nm-+75 nm is used preferably. By using what is the phase difference value (Rth) of these thickness directions from -90 nm-+75 nm, coloring (optical coloring) of the polarizing plate resulting from a transparent protective film can be almost eliminated. The thickness direction retardation value Rth is more preferably -80 nm to +60 nm, particularly preferably -70 nm to +45 nm.

On the other hand, a retardation plate having a phase difference of 40 nm or more and / or a thickness direction retardation of 80 nm or more can be used as the transparent protective film. The front phase difference is usually controlled in the range of 40 to 200 nm, and the thickness direction phase difference is usually controlled in the range of 80 to 300 nm. When using a retardation plate as a transparent protective film, since the said retardation plate also functions as a transparent protective film, thickness can be aimed at.

As a retardation plate, the birefringent film formed by carrying out uniaxial or biaxial stretching process of a polymeric material, the orientation film of a liquid crystal polymer, the thing which supported the orientation layer of a liquid crystal polymer with a film, etc. are mentioned. Although the thickness of a retardation plate is not specifically limited, either, About 20-150 micrometers is common.

Examples of the polymer material include polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polyallylate, Polysulfone, polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polyphenylene sulfide, polyphenylene oxide, polyallyl sulfone, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose resin, cyclic polyolefin resin (nor Borneen resin), or these binary, ternary various copolymers, graft copolymers, blends, etc. are mentioned. These polymeric raw materials become an orientation substance (stretched film) by extending | stretching etc.

Examples of the liquid crystal polymer include various main chain or side chains in which a conjugated linear atomic group (mesogen) for imparting liquid crystal alignment is introduced into the main chain or side chain of the polymer. Specific examples of the main chain type liquid crystal polymer include, for example, a nematic oriented polyester liquid crystal polymer, a discotic polymer or a cholesteric polymer having a structure in which a mesogenic group is bonded to a spacer portion providing flexibility. have. As a specific example of a side chain type liquid crystal polymer, the para substituted ring of a nematic orientation imparting property is provided through the spacer part which consists of polysiloxane, polyacrylate, polymethacrylate, or polymalonate as a main chain skeleton, and a conjugated atomic group as a side chain. The thing which has the mesogenic part which consists of a type compound unit, etc. are mentioned. These liquid crystal polymers, for example, by rubbing the surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate, the solution of the liquid crystalline polymer on the alignment treatment surface such as silicon oxide deposited on all sides It expands and heat-processes.

The retardation plate may be any one having a phase difference appropriately according to the purpose of use, for example, for the purpose of compensation of coloration or time due to birefringence of various wavelength plates and liquid crystal layers, and the like. The optical characteristic of this may be controlled.

The phase difference plate satisfies the relationship of nx = ny> nz, nx> ny> nz, nx> ny = nz, nx> nz> ny, nz = nx> ny, nz> nx> ny, nz> nx = ny It is selected according to various uses. In addition, ny = nz means not only the case where ny and nz are exactly the same, but also the case where ny and nz are substantially the same.

For example, in the retardation plate which satisfy | fills nx> ny> nz, it is preferable to use that whose front phase difference is 40-100 nm, thickness direction phase difference is 100-320 nm, and Nz coefficient satisfy | fills 1.8-4.5. For example, in the retardation plate (positive A plate) which satisfies nx> ny = nz, it is preferable to use the thing whose front retardation satisfy | fills 100-200 nm. For example, in a phase difference plate (negative A plate) which satisfy | fills nz = nx> ny, it is preferable to use the thing whose front phase difference satisfy | fills 100-200 nm. For example, in the retardation plate which satisfy | fills nx> nz> ny, it is preferable to use the thing whose front phase difference exceeds 150-300 nm and Nz coefficient exceeds 0 and satisfy | fills -0.7. As described above, for example, one that satisfies nx = ny> nz, nz> nx> ny, or nz> nx = ny can be used.

A transparent protective film can be suitably selected according to the liquid crystal display device applied. For example, in the case of VA (including Vertical Alignment, MVA, and PVA), it is preferable that the transparent protective film of at least one side (cell side) of the polarizing plate has a phase difference. It is preferable that it is the range of Re = 0-240 nm and Rth = 0-500 nm as a specific phase difference. Speaking of three-dimensional refractive index, the case of nx> ny = nz, nx> ny> nz, nx> nz> ny, nx = ny> nz (one-axis, two-axis, Z-shaped, negative C plate) is preferable. When using a polarizing plate up and down of a liquid crystal cell, the upper and lower sides of a liquid crystal cell may have a phase difference, or any one of the upper and lower transparent protective films may have a phase difference.

For example, in the case of IPS (In-Plane Switching, FFS is included), when the transparent protective film of one side of a polarizing plate has a phase difference, any of the cases in which it is not used can be used. For example, when it does not have a phase difference, it is preferable when the upper and lower sides (cell side) of a liquid crystal cell do not have a phase difference. In the case of having a phase difference, when both the upper and lower sides of the liquid crystal cell have a phase difference, it is preferable that either one of the upper and lower sides has a phase difference (for example, when Z is at the upper side and there is no phase difference at the lower side, or the upper side is preferable). On the A plate, on the lower side for positive C plate). When it has a phase difference, the range of Re = -500-500 nm and Rth = -500-500 nm is preferable. Speaking of three-dimensional refractive index, nx> ny = nz, nx> nz> ny, nz> nx = ny, nz> nx> ny (uniaxial, Z-shaped, positive C plate, positive A plate) is preferable.

In addition, the film having the retardation may be attached separately to the transparent protective film having no retardation to impart the above function.

The surface which does not adhere | attach the polarizer of the said transparent protective film (the surface which does not form an easily bonding layer) is what performed the process for the purpose of a hard-coat layer, an antireflection process, sticking prevention, and diffusion | diffusion or antiglare. You can do it.

The hard coat treatment is performed for the purpose of preventing the occurrence of scratches on the surface of the polarizing plate, for example, by adding a cured film excellent in hardness, slipping properties, etc., by UV-curable resins such as acrylic or silicone, to the surface of the transparent protective film. It can form in a manner etc. The antireflection treatment is performed for the purpose of preventing reflection of external light on the surface of the polarizing plate, and can be achieved by forming an antireflection film or the like according to the prior art. In addition, the sticking prevention treatment is performed for the purpose of preventing adhesion to an adjacent layer (for example, a diffuser plate on the backlight side).

In addition, antiglare treatment is performed for the purpose of preventing external light from reflecting off the surface of the polarizing plate and impairing the visibility of the polarizing plate transmitted light. For example, blending of roughening method or transparent fine particles by sandblasting or embossing It can form by providing a fine uneven | corrugated structure to the surface of a transparent protective film by appropriate methods, such as a system. Examples of the fine particles to be included in the formation of the surface fine uneven structure include conductive materials composed of silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide and the like having an average particle diameter of 0.5 to 20 µm, for example. Transparent fine particles, such as organic fine particles which consist of inorganic fine particles, crosslinked or uncrosslinked polymers, and the like are used. When forming a surface fine uneven structure, the usage-amount of microparticles | fine-particles is generally about 2-70 weight part with respect to 100 weight part of transparent resin which forms a surface fine uneven structure, and 5-50 weight part is preferable. The antiglare layer may also serve as a diffusion layer (visual magnification function, etc.) for diffusing the polarizing plate transmitted light to enlarge the vision and the like.

The antireflection layer, the sticking prevention layer, the diffusion layer, the antiglare layer, and the like can be formed on the transparent protective film itself, and can be formed as a separate optical layer from the transparent protective film.

The polarizing plate of this invention is manufactured by attaching a transparent protective film and a polarizer using the said adhesive agent. Moreover, an easily bonding layer is formed between the transparent protective film and the adhesive bond layer formed by an adhesive agent. After the said easily bonding layer is normally formed on a transparent protective film, it is affixed with the said adhesive so that the said easily bonding layer and a polarizer may face.

In the attachment process in the said manufacturing method, after the said adhesive coats the surface which forms the said adhesive bond layer of a polarizer, and / or the easily bonding layer surface of a transparent protective film, the easily bonding layer of a polarizer and a transparent protective film for said polarizing plates Attaching through an adhesive; Next, it has the process of irradiating an active energy ray (electron beam, an ultraviolet-ray, etc.) with respect to the polarizer and transparent protective film which were attached through the said adhesive agent for polarizing plates, and forming an adhesive bond layer.

The polarizer, the transparent protective film, and the easily bonding layer may be subjected to a surface modification treatment before coating the adhesive. Specific treatments include corona treatment, plasma treatment, and saponification treatment.

The coating method of an adhesive agent is suitably selected by the viscosity of an adhesive agent, and the thickness made into the objective. As an example of a coating system, a reverse coater, a gravure coater (direct, reverse or offset), a bar reverse coater, a roll coater, a die coater, a bar coater, a load coater etc. are mentioned, for example. In addition, methods, such as a dipping method, can be used suitably for coating.

A polarizer and a transparent protective film are affixed through the adhesive agent coated as mentioned above. Attachment of a polarizer and a transparent protective film can be performed by a roll laminator etc.

After attaching a polarizer and a transparent protective film, an active energy ray (electron beam, an ultraviolet-ray, etc.) is irradiated to harden an adhesive agent. The irradiation direction of an active energy ray (electron beam, ultraviolet rays, etc.) can be irradiated from arbitrary appropriate directions. Preferably, it irradiates from the transparent protective film side. When irradiated from the polarizer side, there exists a possibility that a polarizer may deteriorate by active energy rays (electron beam, an ultraviolet-ray, etc.).

It is preferable to use an active energy ray hardening-type adhesive agent as an electron beam hardening type. Arbitrary suitable conditions can be employ | adopted as long as the irradiation conditions of an electron beam can harden the said adhesive agent. For example, as for electron beam irradiation, acceleration voltage becomes like this. Preferably it is 5 kV-300 kV, More preferably, it is 10 kV-250 kV. If the acceleration voltage is less than 5 kV, the electron beam does not reach the adhesive and there is a risk of hardening. If the acceleration voltage exceeds 300 kV, the penetration force through the sample is too strong and the electron beam is bounced and bent, resulting in a transparent protective film or the like. There is a risk of damaging the polarizer. As irradiation dose, it is 5-100 kGy, More preferably, it is 10-75 kGy. In the case where the irradiation dose is less than 5 kGy, the adhesive becomes insufficient in curing, and when it exceeds 100 kGy, damage to the transparent protective film or the polarizer may cause damage to the mechanical strength or yellowing, and thus the predetermined optical properties may not be obtained.

When hardening by ultraviolet irradiation, 0.1-5 weight part of polymerization initiators, Preferably 1-4 weight part, More preferably, 2-3 weight part is mix | blended with respect to 100 weight of curable components. Any appropriate conditions can be adopted as long as irradiation conditions of ultraviolet rays are conditions which can harden the said adhesive agent. It is preferable that it is 100-500mJ / cm <2> by the accumulated light quantity, and, as for the irradiation amount of an ultraviolet-ray, it is more preferable that it is 200-400mJ / cm <2>.

The thickness of the adhesive bond layer in the polarizing plate of this invention obtained as mentioned above is 0.01-7 micrometers. Preferably it is 0.01-5 micrometers, More preferably, it is 0.01-2 micrometers, More preferably, it is 0.01-1 micrometer. When the said thickness is thinner than 0.01 micrometer, there exists a possibility that the cohesion force of adhesive force itself may not be acquired, and adhesive strength may not be obtained. If the thickness of an adhesive bond layer exceeds 7 micrometers, a polarizing plate cannot satisfy durability.

Electron beam irradiation is normally irradiated in an inert gas, but if necessary, you may carry out on air | atmosphere or the conditions which introduce | transduced oxygen a little. Depending on the material of the transparent protective film, by introducing oxygen appropriately, oxygen inhibition is caused on the transparent protective film surface to which the electron beam first touches, and damage to the transparent protective film can be prevented. You can.

In the case of carrying out the production method in a continuous line, the line speed varies depending on the curing time of the adhesive, but is preferably 1 to 500 m / min, more preferably 5 to 300 m / min, still more preferably 10 to 100 m / min. to be. When the line speed is too small, the productivity is insufficient, or the damage to the transparent protective film is too large to produce a polarizing plate that can withstand durability tests and the like. If the line speed is too large, curing of the adhesive may be insufficient, and the desired adhesiveness may not be obtained.

The polarizing plate of this invention can be used as an optical film laminated | stacked with the other optical layer at the time of practical use. Although there is no limitation in particular about the optical layer, For example, in formation of a liquid crystal display device, such as a reflecting plate, a semi-transmissive plate, a retardation plate (including wavelength plates, such as 1/2 and 1/4), a visual compensation film, etc. The optical layer which may be used can use 1 layer or 2 or more layers. In particular, a reflection type polarizing plate or a semi-transmissive polarizing plate in which a reflecting plate or a transflective reflecting plate is laminated on the polarizing plate of the present invention, an elliptical polarizing plate or circular polarizing plate in which a retardation plate is further laminated on the polarizing plate, and a visual compensation film is further laminated on the polarizing plate. The polarizing plate in which the brightness improvement film is further laminated | stacked on the wide viewing angle polarizing plate which consists of, or a polarizing plate is preferable.

The reflective polarizer is formed by forming a reflective layer on the polarizer, and is used to form a liquid crystal display device of a type that reflects and displays incident light from the viewing side (display side). It is advantageous in that the display device can be made thinner. Formation of a reflective polarizing plate can be performed by a suitable method, such as the method of laying a reflective layer which consists of metal etc. on the single side | surface of a polarizing plate through a transparent protective layer etc. as needed.

As a specific example of a reflective polarizing plate, what provided the reflective layer by laying the foil and vapor deposition film which consist of reflective metals, such as aluminum, on the single side | surface of the transparent protective film which carried out the mat process as needed. Moreover, what contains microparticles | fine-particles in the said transparent protective film to make surface fine concavo-convex structure, and has a reflective layer of a fine concavo-convex structure on it, etc. are mentioned. The reflective layer of the fine concavo-convex structure has an advantage of preventing the unevenness of light and shade by preventing incident light by diffusing the incident light by diffuse reflection. Moreover, the transparent protective film containing microparticles | fine-particles also has the advantage of being able to spread | diffuse when incident light and its reflected light transmit it, and to suppress a light and shade nonuniformity more. The formation of the reflective layer of the finely uneven structure reflecting the surface finely uneven structure of the transparent protective film is a transparent protective layer of metal by an appropriate method such as deposition method or plating method such as vacuum deposition method, ion plating method, sputtering method. It can be carried out by a method of directly laying on the surface of the.

The reflecting plate can also be used as a reflecting sheet or the like formed by forming a reflecting layer on a suitable film conforming to the transparent film instead of the method of directly applying to the transparent protective film of the polarizing plate. In addition, since the reflective layer is usually made of a metal, the use mode in which the reflective surface is covered with a transparent protective film, a polarizing plate, or the like, prevents the reduction of the reflectance due to oxidation, and furthermore, the long-term sustaining point of the initial reflectance, It is preferable at the point of avoiding the separate laying of a protective layer.

In addition, a semi-transmissive polarizing plate can be obtained by making it the semi-transmissive reflective layer, such as the half-mirror which reflects light in the reflective layer, and permeate | transmits in the above. The semi-transmissive polarizing plate is usually formed on the back side of the liquid crystal cell, and when using a liquid crystal display device or the like in a relatively bright atmosphere, reflects incident light from the viewing side (display side) to display an image, and in a relatively dark atmosphere. And a liquid crystal display device of a type for displaying an image by using a built-in light source such as a backlight built in the back side of the transflective polarizing plate. That is, the transflective polarizing plate can save energy of using a light source such as a backlight in a bright atmosphere, and is useful for forming a liquid crystal display device of the type that can be used using a built-in light source even in a relatively dark atmosphere.

An elliptical polarizing plate or circular polarizing plate in which a retardation plate is further laminated on the polarizing plate will be described. In the case of changing linearly polarized light into elliptical polarization or circularly polarized light, or changing elliptical or circularly polarized light into linearly polarized light or changing the polarization direction of linearly polarized light, a retardation plate or the like is used. In particular, a so-called quarter wave plate (also referred to as λ / 4 plate) is used as the phase difference plate which changes linearly polarized light into circularly polarized light or circularly polarized light into linearly polarized light. A half wave plate (also called a λ / 2 plate) is usually used when changing the polarization direction of linearly polarized light.

The elliptical polarizing plate is effectively used for compensating (preventing) the coloration (blue or yellow) caused by the birefringence of the liquid crystal layer of the super twist nematic (STN) type liquid crystal display device, and for displaying a black and white display without the coloration. In addition, it is preferable to control the three-dimensional refractive index because the coloring degree generated when the screen of the liquid crystal display device is viewed from the inclined direction can be compensated (prevented). The circular polarizing plate is effectively used, for example, when adjusting the color tone of an image of a reflective liquid crystal display device in which an image becomes color display, and also has a function of antireflection. As a specific example of the retardation plate described above, a film made of an appropriate polymer such as polycarbonate, polyvinyl alcohol, polystyrene, polymethyl methacrylate, polypropylene or other polyolefin, polyallylate, polyamide, etc. The birefringent film, the orientation film of a liquid crystal polymer, the thing which supported the orientation layer of a liquid crystal polymer with a film, etc. are mentioned. The retardation plate may be one having a suitable retardation according to the purpose of use, for example, for the purpose of compensation of coloration or time due to birefringence of various wavelength plates and liquid crystal layers, and the retardation by laminating two or more retardation plates. The thing which controlled optical characteristics, such as these, may be sufficient.

Moreover, said elliptical polarizing plate and reflective elliptic polarizing plate are laminated | stacked combining suitably a polarizing plate or a reflective polarizing plate, and a phase difference plate. Such elliptical polarizing plates and the like can also be formed by sequentially stacking them separately in the manufacturing process of the liquid crystal display device so as to be a combination of a (reflective) polarizing plate and a retardation plate. It is excellent in stability of quality, lamination workability, etc., and there exists an advantage which can improve manufacturing efficiency, such as a liquid crystal display device.

The visual compensation film is a film for widening the viewing angle so that an image can be seen relatively clearly even when the screen of the liquid crystal display device is viewed from a slightly oblique direction rather than perpendicular to the screen. As such a visually compensating retardation plate, it consists of what supported the alignment layers, such as a liquid crystal polymer, on orientation films, such as a retardation film and a liquid crystal polymer, or a transparent base material, etc., for example. A conventional retardation plate is a polymer film having birefringence uniaxially stretched in the plane direction thereof, whereas a retardation plate used as a visual compensation film is a polymer film having birefringence oriented in the biaxial direction in the plane direction, A bidirectional stretched film, such as a birefringent polymer or a diagonally oriented film, which has a refractive index in the thickness direction that is stretched in one plane in the plane direction and stretched in the thickness direction, is used. As a diagonal oriented film, the thing which carried out the extending | stretching process and / or shrinkage treatment of the polymer film, the thing which carried out the diagonal alignment of the liquid crystal polymer, etc. are mentioned, for example by adhering a heat shrink film to a polymer film and the action of the shrinkage force by heating. . The raw material polymer of the retardation plate is the same as the polymer described in the above retardation plate, and is used for the prevention of coloration due to the change of the viewing angle based on the phase difference by the liquid crystal cell, the expansion of the viewing angle of good visibility, etc. One suitable one can be used.

Moreover, from the point of achieving a wide viewing angle of good visibility, the optical compensation retardation plate which supported the optically anisotropic layer which consists of the alignment layer of a liquid crystal polymer, especially the diagonal alignment layer of a discotic liquid crystal polymer with a triacetylcellulose film can be used preferably. have.

The polarizing plate with a polarizing plate and a brightness enhancing film is usually formed and used on the back side of the liquid crystal cell. The brightness enhancement film reflects linearly polarized light on a predetermined polarization axis or circularly polarized light in a predetermined direction when natural light enters by a backlight such as a liquid crystal display device or reflection from the back side, and thus exhibits a property of transmitting other light. The polarizing plate laminated | stacked with the polarizing plate injects light from a light source, such as a backlight, and acquires the transmitted light of a predetermined polarization state, and light other than the said predetermined polarization state is reflected without transmitting. The light reflected from the surface of the brightness enhancing film is again inverted through a reflecting layer or the like formed on the rear side thereof, and reincident to the brightness enhancing film, and a part or all of the light is transmitted as light in a predetermined polarization state to increase the amount of light that passes through the brightness enhancing film. In addition, the luminance can be improved by supplying polarized light that is hardly absorbed by the polarizer and increasing the amount of light that can be used for liquid crystal display. That is, when light is made to pass through a polarizer from the back side of a liquid crystal cell with a backlight etc. without using a brightness improving film, the light which has a polarization direction which does not correspond to the polarization axis of a polarizer is absorbed by a polarizer and a polarizer It does not penetrate. That is, although it changes also with the characteristic of the polarizer used, about 50% of light is absorbed by a polarizer, and the amount of light which can be used for a liquid crystal image display etc. decreases by that much, and an image becomes dark. The brightness enhancing film repeatedly reflects light having a polarization direction absorbed by the polarizer in the brightness enhancing film without incident on the polarizer, inverts through a reflective layer formed on the back side thereof, and reenters the brightness enhancing film. Since the brightness enhancement film transmits only the polarized light in which the polarization direction of the light reflected and inverted between the two becomes the polarization direction through which the polarizer passes, the light is transmitted to the polarizer so that light such as a backlight can be efficiently displayed on the image of the liquid crystal display device. It can be used to brighten the screen.

A diffusion plate may be formed between the brightness enhancing film and the reflective layer. The light in the polarization state reflected by the brightness enhancement film is directed toward the reflection layer or the like, but the diffuser plate provided uniformly diffuses the light passing therethrough and at the same time eliminates the polarization state and becomes a non-polarization state. In other words, the diffusion plate returns the polarized light to the original natural light state. The light in this non-polarization state, that is, the natural light state, is reflected toward the reflection layer or the like through the reflection layer or the like, and passes through the diffuser plate again and is reincident to the brightness enhancement film. Thus, by forming a diffuser plate that returns the polarization to the original natural light state between the brightness enhancing film and the reflective layer, the brightness of the display screen is maintained while simultaneously reducing the unevenness of the display screen, thereby providing a uniform and bright screen. Can provide. By forming such a diffuser plate, it is considered that the first incident light can be appropriately increased in the number of times of repetition of reflection, thereby providing a uniform bright display screen in conjunction with the diffuser function of the diffuser plate.

As said brightness improving film, it shows the characteristic which transmits linearly polarized light of a predetermined polarization axis, and reflects other light, such as a multilayered thin film of a dielectric and a multilayer laminated body of a thin film of which refractive index anisotropy differs, and cholesteric As supporting the alignment film of the liquid crystal polymer and the alignment liquid crystal layer on the film substrate, suitable ones such as those exhibiting a characteristic of reflecting either circularly polarized light in the left rotation or the right rotation and transmitting other light can be used.

Therefore, in the luminance improvement film of the type which permeate | transmits linearly polarized light of the said predetermined polarization axis, it can transmit efficiently, suppressing the absorption loss by a polarizing plate by making the transmitted light into a polarizing plate as it enters. On the other hand, in the luminance improvement film of the type which transmits circularly polarized light like a cholesteric liquid crystal layer, although it may be made to enter into a polarizer as it is, in view of suppressing absorption loss, the circularly polarized light is linearly polarized through a phase difference plate, and a polarizing plate is used. It is preferable to make it enter. In addition, circular polarization can be converted into linearly polarized light by using a quarter wave plate as the retardation plate.

A retardation plate functioning as a quarter wave plate in a wide wavelength range such as visible light is a retardation layer exhibiting retardation characteristics different from a retardation layer functioning as a quarter wave plate for light color light having a wavelength of 550 nm, for example. For example, it can obtain by the method of superimposing the retardation layer which functions as a 1/2 wave plate. Therefore, the phase difference plate arrange | positioned between a polarizing plate and a brightness improving film should just consist of one layer or two or more phase difference layers.

Moreover, also about a cholesteric liquid crystal layer, when it is set as the arrangement structure which overlapped two or three layers by the combination of a thing with a different reflection wavelength, what reflects circularly polarized light in a wide wavelength range, such as a visible light region, can be obtained and Based on this, transmission circularly polarized light in a wide wavelength range can be obtained.

Moreover, the polarizing plate may consist of what laminated | stacked the polarizing plate and two or three or more optical layers like the said polarization split type polarizing plate. Therefore, the reflective elliptically polarizing plate, the semi-transmissive elliptically polarizing plate, etc. which combined said reflective polarizing plate, semi-transmissive polarizing plate, and retardation plate may be sufficient.

The optical film in which the optical layer is laminated on the polarizing plate may be formed by a method of sequentially laminating the optical film in a manufacturing process such as a liquid crystal display device. However, the optical film laminated in advance is excellent in quality stability and assembly work. There is an advantage that the manufacturing process such as a liquid crystal display device can be improved. Suitable lamination means, such as an adhesion layer, can be used for lamination. In the case of adhering the above-mentioned polarizing plate and other optical films, these optical axes can be made into an appropriate arrangement angle according to the target retardation characteristic etc.

The adhesive layer for adhering with another member, such as a liquid crystal cell, can also be formed in the above-mentioned polarizing plate and the optical film in which at least 1 layer of polarizing plates are laminated | stacked. The pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer is not particularly limited, but for example, an acrylic polymer, a silicone polymer, a polyester, a polyurethane, a polyamide, a polyether, a fluorine-based or a rubber-based polymer may be appropriately selected and used. have. In particular, an acrylic adhesive has excellent optical transparency, exhibits moderate wettability, cohesive and adhesive adhesive properties, and can be preferably used for excellent weather resistance, heat resistance and the like.

In addition to the above, in terms of prevention of foaming or peeling phenomenon due to moisture absorption, reduction of optical characteristics due to thermal expansion difference, prevention of warping of liquid crystal cell, and furthermore, formation of high quality and durable liquid crystal display device, The adhesive layer which has low moisture absorption and excellent heat resistance is preferable.

An adhesive layer is added to adhesive layers, such as fillers, pigments, coloring agents, antioxidants, etc. which consist of resins of a natural substance or a compound, especially tackifying resin, glass fiber, glass beads, metal powder, other inorganic powders, etc., for example. You may contain the additive of what becomes. Moreover, the adhesion layer etc. which contain microparticles | fine-particles and show light diffusivity may be sufficient.

Laying an adhesion layer with respect to one side or both sides of a polarizing plate or an optical film can be performed by a suitable method. As an example, about 10 to 40weight% of the adhesive solution which melt | dissolved or disperse | distributed or disperse | distributed a base polymer or its composition in the solvent which consists of a single substance or mixture of suitable solvents, such as toluene and ethyl acetate, is prepared, The method of laying directly on a polarizing plate or an optical film by appropriate development methods, such as a system and a coating method, or the method of forming an adhesion layer on a separator according to the above, and sticking it on a polarizing plate or an optical film, etc. are mentioned. have.

The pressure-sensitive adhesive layer may be formed on one side or both sides of a polarizing plate or an optical film as an overlapping layer of one having a different composition or kind. Moreover, when formed in both surfaces, it can also be set as adhesive layers, such as a different composition, a kind, thickness, etc. in the front and back of a polarizing plate and an optical film. The thickness of an adhesion layer can be suitably determined according to a use purpose, adhesive force, etc., Generally, it is 1-40 micrometers, 5-30 micrometers is preferable, and 10-25 micrometers is especially preferable. When it is thinner than 1 µm, the durability becomes poor, and when it is thicker than 40 µm, lifting or peeling due to foaming or the like tends to occur, resulting in poor appearance.

About the exposed surface of an adhesion layer, a separator is temporarily affixed and covered for the purpose of the contamination prevention, etc. until it is provided for practical use. Thereby, contact with an adhesion layer can be prevented in a usual handling state. As the separator, except for the above thickness conditions, for example, a plastic film, a rubber sheet, a paper, a cloth, a nonwoven fabric, a net, a foam sheet or a metal foil, and a laminate of a suitable type such as a laminate thereof may be silicone-based or long-chain alkyl-based as necessary. And conventionally appropriate ones such as those coated with an appropriate release agent such as fluorine or molybdenum sulfide can be used.

In order to improve the adhesiveness between a polarizing plate and an adhesive layer, you may provide an anchor layer between the layers.

As a forming material of the said anchor layer, Preferably, the anchor agent chosen from polyurethane, polyester, and the polymer containing an amino group in a molecule | numerator is used, Especially preferably, it is a polymer containing an amino group in a molecule | numerator. Polymers containing an amino group in a molecule ensure good adhesion because the amino group in the molecule exhibits an interaction such as a carboxyl group or the like in the pressure-sensitive adhesive or an ionic interaction.

As polymers containing an amino group in the molecule, for example, polymers of amino group-containing monomers such as polyethyleneimine, polyallylamine, polyvinylamine, polyvinylpyridine, polyvinylpyrrolidine, dimethylaminoethyl acrylate, and the like Can be mentioned.

An antistatic agent can also be added to the said anchor layer in order to provide antistatic property. Examples of antistatic agents for imparting antistatic properties include conductive polymers such as ionic surfactants, polyaniline, polythiophene, polypyrrole, and polyquinoxaline, and metal oxides such as tin oxide, antimony oxide, and indium oxide. In particular, conductive polymers are preferably used in view of optical properties, appearance, antistatic effect, and stability during heating and humidification of the antistatic effect. Among these, water-soluble conductive polymers such as polyaniline and polythiophene or water-dispersible conductive polymers are particularly preferably used. When water-soluble conductive polymers or water-dispersible conductive polymers are used as the material for forming the antistatic layer, deterioration of the optical film substrate by the organic solvent during coating can be suppressed.

In the present invention, for example, a salicylic acid ester compound, a benzophenol compound, a benzotriazole compound, or cyano is used for each layer such as a polarizer, a transparent protective film, an optical film, or the adhesive layer forming the polarizing plate. The thing which gave ultraviolet absorption ability by methods, such as a process with ultraviolet absorbers, such as an acrylate compound and a nickel complex salt compound, may be sufficient.

The polarizing plate or optical film of this invention can be used suitably for formation of various apparatuses, such as a liquid crystal display device. Formation of a liquid crystal display device can be performed according to the prior art. That is, a liquid crystal display device is generally formed by appropriately assembling the component parts, such as a liquid crystal cell, a polarizing plate or an optical film, and an illumination system as needed, and mounting a drive circuit, In this invention, the polarizing plate by this invention Or there is no limitation in particular except using an optical film, and it can follow conventionally. Also about a liquid crystal cell, arbitrary types, such as a TN type, STN type, pi type, VA type, IPS type, can be used, for example.

An appropriate liquid crystal display device, such as a liquid crystal display device in which a polarizing plate or an optical film is disposed on one side or both sides of a liquid crystal cell, or a backlight or reflecting plate used in an illumination system, can be formed. In that case, the polarizing plate or optical film by this invention can be provided in the one side or both sides of a liquid crystal cell. When forming a polarizing plate or an optical film in both sides, they may be the same and may differ. At the time of formation of the liquid crystal display device, for example, a diffuser plate, an antiglare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffuser plate, a backlight, or the like and an appropriate component at one or two or more layers in appropriate positions. Can be placed.

Next, an organic electroluminescent device (organic EL display device) will be described. In general, an organic EL display device forms a light emitting body (organic electroluminescent light emitting body) by sequentially stacking a transparent electrode, an organic light emitting layer, and a metal electrode on a transparent substrate. Here, an organic light emitting layer is a laminated body of various organic thin films, For example, the laminated body of the hole injection layer which consists of triphenylamine derivatives, etc., and the light emitting layer which consists of fluorescent organic solids, such as anthracene, or such a light emitting layer and perylene The structure which has various combinations, such as the laminated body of the electron injection layer which consists of derivatives, etc., or these laminated bodies of a hole injection layer, a light emitting layer, and an electron injection layer is known.

In the organic EL display device, holes and electrons are injected into the organic emission layer by applying a voltage to the transparent electrode and the metal electrode, and energy generated by the recombination of these holes and electrons excites the fluorescent material, and the excited fluorescent material is based on It emits light on the principle of emitting light when returning to the state. The mechanism of intermediate recombination is the same as that of a general diode, and as can be expected from this, the current and the emission intensity exhibit strong nonlinearity accompanied by rectification with respect to the applied voltage.

In the organic EL display device, in order to extract light emission from the organic light emitting layer, at least one electrode must be transparent, and a transparent electrode formed of a transparent conductor such as indium tin oxide (ITO) is usually used as an anode. On the other hand, in order to increase the luminous efficiency by facilitating electron injection, it is important to use a material having a small work function for the cathode, and metal electrodes such as Mg-Ag and Al-Li are usually used.

In the organic EL display device having such a configuration, the organic light emitting layer is formed of a very thin film having a thickness of about 10 nm. For this reason, the organic light emitting layer also transmits light almost completely like the transparent electrode. As a result, light incident on the surface of the transparent substrate during non-emission, and transmitted through the transparent electrode and the organic light emitting layer and reflected from the metal electrode again comes out to the surface side of the transparent substrate, so that when viewed from the outside, The display surface looks like a mirror.

An organic EL display device comprising an organic electroluminescent light-emitting body comprising a transparent electrode on the front side of an organic light emitting layer that emits light by application of a voltage and a metal electrode on the back side of the organic light emitting layer, wherein the organic EL display device is transparent. While forming a polarizing plate on the surface side of an electrode, a phase difference plate can be formed between these transparent electrodes and a polarizing plate.

Since the retardation plate and the polarizing plate have a function of polarizing light incident from the outside and reflected from the metal electrode, the retardation plate and the polarizing plate do not visually recognize the mirror surface of the metal electrode from the outside. In particular, when the phase difference plate is constituted by a quarter wave plate, and the angle between the polarization direction of the polarizing plate and the phase difference plate is adjusted to π / 4, the mirror surface of the metal electrode can be completely shielded.

That is, only the linearly polarized light component is transmitted to the external light incident on the organic EL display device by the polarizing plate. This linearly polarized light is generally elliptically polarized by the retardation plate, but especially when the retardation plate is a quarter wave plate, and the angle constituting the polarization direction of the polarizing plate and the retardation plate is? / 4.

The circularly polarized light penetrates the transparent substrate, the transparent electrode, and the organic thin film, is reflected by the metal electrode, and again passes through the organic thin film, the transparent electrode, and the transparent substrate, and is again linearly polarized on the retardation plate. And since this linearly polarized light is orthogonal to the polarization direction of a polarizing plate, it cannot pass through a polarizing plate. As a result, the mirror surface of a metal electrode can be shielded completely.

Although the Example of this invention is described below, embodiment of this invention is not limited to these.

(Polarizer)

A polyvinyl alcohol film having an average degree of polymerization of 2400, a degree of saponification of 99.9 mol% and a thickness of 75 µm was immersed in hot water at 30 ° C for 60 seconds to swell. Next, it extended | stretched to 3.5 times, dyeing for 1 minute in 30 degreeC iodine solution of 0.3 weight% (weight ratio: iodine / potassium iodide = 0.5 / 8). Thereafter, the total draw ratio was stretched to 6 times while immersing in a 4 wt% aqueous boric acid solution at 65 ° C. for 0.5 min. After extending | stretching, it dried for 3 minutes in 70 degreeC oven, and obtained the polarizer of thickness 26micrometer. The moisture content of the polarizer was 13.5 weight%.

(Transparent protective film)

Lactoneized polymethyl methacrylate film (Lactonation rate 20%, Thickness 30 micrometers, Re = 0 nm, Rth = 0 nm; It shows by LMMA in Table 1),

Norbornene-based resin film (manufactured by Japan Xeon Co., Ltd., trade name Zeonoa, thickness 40 µm; represented by Zeonoa in Table 1),

Polyester resin film (Mitsubishi Resin Co., Ltd. make, brand name S100-38, thickness 38 micrometers; It shows by S100-38 in Table 1), or,

A cellulose resin film (manufactured by Konica Minolta Opt Co., Ltd., brand name KC4UY, thickness 40 µm; represented by KC4UY in Table 1) was used.

(Phase difference value)

The measurement of the retardation value was nx, ny, nz measured with respect to the value of wavelength 590nm using the retarder (Oji Measurement Instruments Co., Ltd. product, product name "KOBRA21-ADH") based on the parallel Nicole rotation method. From the value of and the film thickness (d), front phase difference (Re), thickness direction phase difference Rth, and Nz were calculated | required. [However, the refractive indexes of the slow axis direction, the fast axis direction, and the thickness direction of the film are respectively nx, ny, and nz, and d (nm) is the thickness of the film. The slow axis direction is a direction that maximizes the refractive index in the film plane.

Example 1

(Adhesive: Curable Component)

N-hydroxyethylacrylamide was used as the adhesive.

(Formation of easily bonding layer)

10 parts by weight of 3-acryloxypropyltrimethoxysilane (KBM5103, manufactured by Shin-Etsu Silicone Co., Ltd.) to 100 parts by weight of a polymer having a polyester skeleton (Superflex SF210, manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.) The blended forming material (solid content concentration 11 weight%) was prepared. The forming material was coated on one side of the transparent protective film (lactonated polymethyl methacrylate film) using a bar coater to have a thickness of 0.3 μm, dried at 150 ° C., and an easy adhesion layer was formed on the transparent protective film.

(Manufacture of Polarizing Plate)

Transparent protection which coated the adhesive agent to the thickness of 5 micrometers using the microgravure coater (gravure roll: # 300, rotation speed 140% / line speed) to the easily bonding layer formed on the said transparent protective film so that it might become thickness of 5 micrometers. It was set as the film. Next, the transparent protective film to which the said adhesive agent was apply | coated this was affixed from the both surfaces of the said polarizer with a roll machine. The electron beam was irradiated from the attached transparent protective film side (both sides), and the polarizing plate which has a transparent protective film on both sides of the polarizer was obtained. The line speed was 20 m / min, the acceleration voltage was 250 Hz, and the irradiation dose was 20 kGy.

Examples 2 to 13, Comparative Examples 1 to 19

In Example 1, when using together the kind of transparent protective film, the kind of adhesive agent (curable component), and its ratio; The polarizing plate was obtained like Example 1 except having changed the polymer resin to form the easily bonding layer, the kind of additive, or their usage amount as shown in Table 1.

Example 14

(Adhesive: Curable Component)

What mix | blended 3 weight part of photoinitiators (made by Chiba Japan Co., Ltd .; brand name Irugacure 127) with 100 weight part of N-hydroxyethyl acrylamide was used as an adhesive agent.

(Manufacture of Polarizing Plate)

A microgravure coater (gravure roll: # 300) prepared in the same manner as in Example 1 (formation of easy bonding layer) was prepared on the easy bonding layer formed on the transparent protective film (lactone polymethyl methacrylate film). And a rotating speed of 140% / line speed) to form a transparent protective film coated with an adhesive coated with a thickness of 5 µm. Subsequently, the transparent protective film apply | coated with the said adhesive machine was stuck by the roll machine from both surfaces of the said polarizer. Ultraviolet was irradiated from the transparent protective film side (both sides) which were affixed, and the polarizing plate which has a transparent protective film on both sides of a polarizer was obtained. The line speed was 20 m / min and the integrated light quantity was 200 mJ / cm <2> with respect to one side.

Comparative Examples 20 and 21

In Example 1, the polarizing plate was obtained like Example 1 except having changed the need of the polymer resin and additive which the easily bonding layer forms, as shown in Table 1.

[evaluation]

The following evaluation was performed about the polarizing plates obtained by the Example and the comparative example. The results are shown in Table 1.

<Adhesive force>

The obtained polarizing plate was cut out in the size of 15 mm x 150 mm, and it was set as the sample. The sample was affixed on the glass plate by the double-sided adhesive tape (Nitto Electric Co., Ltd. product, No. 500). The sample (polarizing plate) was previously marked between a transparent protective film and a polarizer, and the display was chucked by the variable angle peel tester (made by Asahi Seiko Co., Ltd.), and the peeling strength (N / 15mm) was measured. Measurement conditions were made into normal temperature (23 degreeC), peel angle: 90 degree, and peel speed: 3000 mm / min. Table 1 shows the average value of the data between 50 mm and 100 mm of the obtained measurement data.

In Table 1,

<Adhesive>

HEAA: N-hydroxyethylacrylamide.

ACMO: N-acryloyl morpholine,

<Forming material of the easy bonding layer: polymer resin>

SF210: polymer having a polyester skeleton (Superflex SF210, manufactured by Daiichi Pharmaceutical Co., Ltd.),

WLS202: Polymer having a polyether skeleton (Hylan WLS202, manufactured by Dainippon Ink Chemical Industries, Ltd.),

<Forming material of the easy bonding layer: auxiliary agent>

KBM5103: 3-acryloxypropyltrimethoxysilane (KBM5103, manufactured by Shin-Etsu Silicone Co., Ltd.),

KBM803: 3-mercaptopropylmethyldimethoxysilane (KBM803, manufactured by Shin-Etsu Silicone Co., Ltd.),

KBM503: 3-methacryloxypropyltriethoxysilane (KBM503, manufactured by Shin-Etsu Silicone Co., Ltd.),

KBM1003: vinyl trimethoxysilane (KBM1003, manufactured by Shin-Etsu Silicone Co., Ltd.),

MS51: methyl silicate 51 (manufactured by Fuso Chemical Industry Co., Ltd.),

N-MAN: N-methylol acrylamide

M-3: trimethylolmelamine (M-3, manufactured by Dainippon Ink Chemical Industry Co., Ltd.),

WS700: oxazoline (WS700, manufactured by Nihon Catalyst Chemical Co., Ltd.),

KBM403: 3-glycidoxypropyltrimethoxysilane (KBM403, manufactured by Shin-Etsu Silicone Co., Ltd.),

KBE585: 3-ureidopropyltriethoxysilane (KBE585, manufactured by Shin-Etsu Silicone Co., Ltd.),

KBM603: N-2- (aminoethyl) -3-aminopropyltrimethoxysilane (KBM603, Shin-Etsu Silicone Co., Ltd. product) is shown.

Claims (8)

As a polarizing plate in which the transparent protective film is formed through the adhesive bond layer and the easily bonding layer in this order on at least one surface of a polarizer, The adhesive layer is formed of an active energy ray curable adhesive containing an N-substituted amide monomer having a hydroxyl group as a curable component, In addition, the easily bonding layer contains 3 to 30 parts by weight of an organosilane compound having at least one functional group selected from acryloyl, methacryloyl, vinyl and mercapto groups based on 100 parts by weight of the polymer resin. It is formed of the polymer resin composition to be characterized by the polarizing plate characterized by the above-mentioned. The method of claim 1, The polymer resin which forms an easily bonding layer has a polyester skeleton, The polarizing plate characterized by the above-mentioned. The method of claim 1, As a curing component, and the general formula _{(1): CH 2 = C} (R 1) -CONR 2 (R 3) (R 1 is a hydrogen atom or a methyl group, R ² is a hydrogen atom or a mercapto group, an amino group or the out it represents the quaternary linear or branched alkyl group chain having from 1 to 4 carbon atoms which may have a an ammonium group, R ³ represents a straight-chain or branched alkyl group chain of hydrogen or carbon number of 1 to 4. However, R ^2, R Except when ³ is a hydrogen atom at the same time, or R <^2> , R <^3> combines and forms the 5-membered ring or 6-membered ring which may contain an oxygen atom.) It contains, The polarizing plate characterized by the above-mentioned. The method of claim 1, An active energy ray-curable adhesive is an electron beam-curable adhesive. The method of claim 1, A polarizing plate, wherein the transparent protective film is at least one selected from cellulose resin, polycarbonate resin, cyclic polyolefin resin, polyester resin, and (meth) acrylic resin. As a manufacturing method of the polarizing plate in any one of Claims 1-5 in which the transparent protective film is formed through the adhesive bond layer and the easily bonding layer in this order on at least one surface of a polarizer, With polarizer, To a polymer resin composition containing 3 to 30 parts by weight of an organosilane compound having at least one functional group selected from acryloyl, methacryloyl, vinyl and mercapto groups based on 100 parts by weight of the polymer resin. The transparent protective film in which the easily bonding layer formed by A step of adhering with an active energy ray-curable adhesive containing an N-substituted amide monomer having a hydroxyl group as a curable component such that the easily bonding layer formed on the transparent protective film and the polarizer face each other, Next, it has a process of hardening the said adhesive agent by active energy ray irradiation and forming an adhesive bond layer, The manufacturing method of the polarizing plate characterized by the above-mentioned. At least one polarizing plate of Claim 1 is laminated | stacked, The optical film characterized by the above-mentioned. The polarizing plate of any one of Claims 1-5, or the optical film of Claim 7 is used, The image display apparatus characterized by the above-mentioned.