JP6965509B2 - Film winding layer - Google Patents

Description

The present invention relates to a film wound layer provided with a resin film that can be used as, for example, a polarizer protective film.

In a liquid crystal display device, two polarizing plates are usually arranged on both sides of a liquid crystal cell.
The polarizing plate is generally one in which protective films are attached to both sides of the polarizing element using a water-soluble adhesive such as polyvinyl alcohol.
As the polarizer, a film obtained by adsorbing iodine or a dichroic dye on a film formed by forming a film of polyvinyl alcohol by a solution casting method and stretching it in a boric acid solution has been generally used.

On the other hand, as a protective film to be bonded to a polarizer, a cellulosic film such as a triacetyl cellulose film has been widely used.
However, the durability, heat resistance, mechanical strength, etc. of the cellulose-based film are not sufficient, and a polarizing plate using this as a polarizer protective film can be used in a high humidity and heat environment, or the entire image display device becomes thinner. If the distance from the heat source such as a light source becomes short, the polarizing plate characteristics such as the degree of polarization and the color difference may be impaired due to expansion and deformation. Therefore, in recent years, as a material having excellent heat resistance, durability, and optical transparency, a film made of an acrylic resin (referred to as an "acrylic film") and a film containing an alicyclic structure-containing polymer have been used as a polarizer protective film. It is attracting attention as.

However, such films have a poorer affinity with water-soluble adhesives used in the production of polarizing plates than cellulosic films, and therefore, in order to improve the adhesiveness, they are applied to the surfaces of these films. It has been proposed to perform a hydrophilization treatment (corona discharge treatment or plasma treatment) or to provide an easy-adhesion layer on the surface of the film (for example, Patent Documents 1 and 2).

Further, Patent Document 3 describes polyurethane and epoxy having a carboxyl group in a (meth) acrylic protective film containing a crosslinked elastic body in order to provide a polarizer protective film having excellent adhesion to a polarizer and excellent strength. It is proposed to form an easy-adhesive layer made of an easy-adhesive composition containing a cross-linking agent having a group on a (meth) acrylic film.

JP-A-2007-127893 Japanese Unexamined Patent Publication No. 2008-216910 Japanese Unexamined Patent Publication No. 2016-33552

Since the protective film to be bonded to the polarizer is thin, the film is likely to break due to the tension applied during the production line, which may cause a decrease in yield and the like, making the bonding work difficult. There was also the problem of poor handleability. Therefore, the inventors can laminate the release film on the protective film until the bonding work, and peel off the release film in the process of manufacturing the polarizing plate using the protective film. A film-wrapped layer was examined.

However, when an easy-adhesion layer was formed on one surface of the polarizer protective film and a release film was laminated on the other surface, the laminated film was wound into a roll to form a film-wrapped layer, and the film-wrapped layer was formed. When rewound, the laminated films adhere to each other due to the adhesion between the easy-adhesion layer and the release film, causing blocking that makes it difficult to slip or peels off, whitening the surface of the protective film, or whitening the surface or edges. Abnormalities such as cracks may occur in the part. Further, in the process of rewinding the film-wrapped layer to manufacture the polarizing plate, the protective film may be wrinkled or torn when the release film is peeled off.

Therefore, the present invention comprises providing an easy-adhesion layer (B) on one surface of a resin film (A) that can be used as a protective film, and laminating a release film (C) on the other surface of the resin film (A). With respect to a film-wrapped layer formed by winding a laminated film having a structure in a roll shape, when the film-wound layer is rewound while ensuring high adhesiveness in bonding with a polarizer by an easy-adhesion layer. In addition, it is possible to suppress the occurrence of blocking such that the films are in close contact with each other and become difficult to slip or peel off, and moreover, when the release film (C) is peeled off, the resin film (A) is wrinkled or torn. It is intended to provide a new film-wrapped layer body in which the above does not occur.

The present invention comprises a resin film (A) containing at least one layer containing an acrylic polymer, an alicyclic structure-containing polymer, or a mixture of these polymers as a main component resin, and one surface side of the resin film (A). A laminated film having a laminated easy-adhesion layer (B) and a detachable release film (C) laminated on the other surface side of the resin film (A) is wound in a roll shape. It is a film-wrapped layer made of
The release film (C) has a base material layer (C1) and an adhesive layer (C2).
Delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C), and delamination strength F2 (N / 20 mm width) between the release film (C) and the easy-adhesion layer (B). ), Both F1 and F2 are 0.01 or more and 1.0 or less, and F2 is larger than F1.

According to the film-wrapped layer body proposed by the present invention, the films adhere to each other when the film-wrapped layer body is rewound while ensuring high adhesiveness in bonding with the polarizer by the easy-adhesion layer. It is possible to suppress the occurrence of blocking that makes it difficult to slip or peel off, and further, it is possible to suppress the occurrence of wrinkles and tears in the resin film (A) when the release film (C) is peeled off. Can be done.

Next, the present invention will be described based on examples of embodiments. However, the present invention is not limited to the embodiments described below.

<This film winding layer>
The film winding layer body (referred to as "the present film winding layer body") according to an example of the embodiment of the present invention is an easy-adhesion layer formed by laminating a resin film (A) and a resin film (A) on one surface side. A laminated film (referred to as "the present laminated film") comprising (B) and a release film (C) laminated on the other side of the resin film (A), that is, on the opposite side of the one side. , A film-wrapped layer formed by being rolled into a roll.

In the present film winding layer, the winding tension per 1 m of the film width, that is, the winding tension is preferably 10 N / m width or more and 200 N / m width or less.
When the winding tension is 10 or more and 200 N / m or less, winding shift, winding swelling, and winding wrinkles do not occur, and an increase in phase difference due to film orientation due to tension can be reduced, which is preferable.
From this point of view, in the present film winding layer, the winding tension per 1 m of the film width is preferably 10 or more and 200 N / m width or less, and more preferably 20 N / m width or more or 150 N / m width or less. preferable.

In this film winding layer, the delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C) and the interlayer between the release film (C) and the easy-adhesion layer (B) are formed. It is preferable that the relationship with the peel strength F2 (N / 20 mm width) is 0.01 or more and 1.0 or less for both F1 and F2, and F2 is larger than F1.
At this time, the delamination strength F1 between the resin film (A) and the release film (C) is the delamination strength F1 between the resin film (A) and the release film (C) in the laminated film having the same winding circumference. Means.
Further, the delamination strength F2 between the release film (C) and the easy-adhesion layer (B) is set in the release film (C) and the laminated film of the winding circuit adjacent to the laminated film of the release film (C). It means the delamination strength F2 with the easy-adhesion layer (B).

For example, in a film-wrapped layer having a laminated structure such as a release film (C) / easy-adhesion layer (B) / resin film (A), delamination between adjacent laminated films is performed so that the film can be smoothly unwound. It is usual to increase the delamination strength in the laminated film rather than the strength.
On the other hand, in this film wound layer, the delamination between the release film (C) and the easy-adhesion layer (B) is higher than the delamination strength F1 between the resin film (A) and the release film (C). By increasing the strength F2 and setting both F1 and F2 to 0.01 or more and 1.0 or less, when the film winding layer is rewound, the films adhere to each other and become difficult to slip or peel off. It is characterized in that it is possible to suppress the occurrence of blocking, and it is possible to suppress the occurrence of wrinkles and tears in the resin film (A) when the release film (C) is peeled off. There is.

Further, the delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C) is preferably 0.01 or more and 0.1 or less, and more than 0.02 or more or 0. It is more preferably 09 or less, and particularly preferably 0.03 or more or 0.08 or less.

As will be described later, in order to bring F1 into the above range, it is preferable that the release film (C) has an adhesive layer on the surface side in contact with the resin film (A). Further, when the easy-adhesion layer (B) is formed on the resin film (A) to which the release film (C) is previously bonded, the drying temperature thereof is preferably less than 110 ° C. However, the method is not limited to these methods.

The delamination strength F2 (N / 20 mm width) between the release film (C) and the easy-adhesion layer (B) is preferably 0.01 or more and 1.0 or less, particularly 0.02 or more or 0. It is more preferably 8.8 or less, and particularly preferably 0.03 or more or 0.6 or less.
As will be described later, in order to bring F2 into the above range, the thickness and hardness (storage elastic modulus) of the easy-adhesion layer (B) may be adjusted. However, the method is not limited to these methods.

Further, in the present film winding layer, the delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C), and the release film (C) and the easy-adhesion layer (B) are combined. The difference (F2-F1) in the delamination strength F2 (N / 20 mm width) is preferably 0.01 or more and 0.05 or less, and more preferably 0.01 or more and 0.03 or less.

The delamination strength F3 (N / 20 mm width) between the resin film (A) and the easy-adhesion layer (B) is not particularly limited as long as it does not peel off from each other after the easy-adhesion layer is formed on the resin film. It is preferably 0 or more and 10 or less, more preferably 1.5 or more or 9.0 or less, and particularly preferably 2.0 or more or 8.0 or less.
To adjust the delamination strength F3 between the resin film (A) and the easy-adhesion layer (B), adjust the thickness and hardness (storage elastic modulus) of the easy-adhesion layer (B), or adjust the easy-adhesion layer (B). The composition of B) may be adjusted. However, the method is not limited to this method.

As the resin composition constituting the easy-adhesion layer (B), as described later, a resin composition that can be bonded to the PVA film using a water-soluble adhesive is preferable, and among them, a urethane group, an amide group, or a resin composition is preferable. , A resin composition containing a polymer having an NCO group as a main component is preferable, and a resin composition containing a urethane-based resin as a main component is particularly preferable.
Further, as the urethane-based resin forming the main component resin of the easy-adhesion layer (B), as will be described later, it is possible to form an easy-adhesion layer having excellent heat resistance and water resistance and having the optimum storage elasticity in the present invention. Therefore, a urethane resin having an aliphatic polycarbonate skeleton, specifically, a urethane resin obtained by reacting an aliphatic polycarbonate polyol with an aliphatic diisocyanate compound and / or an alicyclic diisocyanate compound is preferable.

The delamination strengths F1 and F2 can be measured in accordance with JIS-Z0237 (2009) as shown in Examples described later.

<Resin film (A)>
The resin film (A) is an acrylic polymer, an alicyclic structure-containing polymer, or an alicyclic structure-containing polymer because it is excellent in transparency, low birefringence, low water absorption, and heat resistance required for use as a polarizer protective film. It contains at least one layer containing a mixture of these polymers as a main component resin. For example, a polarizer protective film constituting a polarizing plate, that is, a resin film that can be used as a polarizer protective film bonded to both sides of the polarizing element can be preferably used. However, the present invention is not limited to this.

The thickness of the resin film (A) is preferably 3 μm or more and 80 μm or less. If it is 3 μm or more, it is preferable because deformation due to shrinkage of the polarizing element in the polarizing plate and permeation of moisture in the air to the polarizer can be suppressed. On the other hand, if it is 80 μm or less, the weight and thickness of the polarizing plate can be reduced. Therefore, it is preferable.
From this point of view, the thickness of the resin film (A) is preferably 3 μm or more and 80 μm or less, more preferably 5 μm or more or 40 μm or less, and particularly preferably 10 μm or more or 30 μm or less.

If necessary, the surface of the resin film (A) may be treated with boric acid to activate the surface to enhance the adhesive force, or may be treated with plasma or corona.

As the main component resin constituting the resin film (A), an acrylic polymer, an alicyclic structure-containing polymer, or a mixture thereof is selected from the viewpoint of excellent heat resistance, durability, and optical transparency. Is preferable.

The resin film (A) has a delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C), and delamination between the release film (C) and the easy-adhesion layer (B). Regarding the relationship with the strength F2 (N / 20 mm width) As long as F1 and F2 are both 0.01 or more and 1.0 or less and F2 is larger than F1, there is no particular limitation, but the acrylic polymer can be used. A layer containing a main component resin (also referred to as an "acrylic resin layer"), a layer containing an alicyclic structure-containing polymer as a main component resin (also referred to as an "alicyclic structure resin layer"), or a weight thereof. It may be a single-layer film composed of a layer (also referred to as "acrylic / alicyclic structural resin layer") containing a mixture of coalesced components as a main component resin, or these acrylic resin layers, alicyclic structural resin layers and acrylics. -A multi-layer film containing one layer or a plurality of layers of the alicyclic structural resin layer may be used.
The multilayer film may have two layers, three layers, four layers or more.

When the resin film (A) is a multi-layer film, the correlation peel strengths F1 and F2 can be easily adjusted within the above-mentioned ranges, and thus the acrylic resin layer, the alicyclic structural resin layer, or the acrylic / fat A multi-layer film having a cyclic structural resin layer as the outermost surface layer is preferable.
When the resin film (A) is a multi-layer film, it may be provided with a layer other than the acrylic resin layer, the alicyclic structural resin layer and the acrylic / alicyclic structural resin layer, and the other layers include. For example, cellulose esters such as polyethylene, polypropylene, cellulose, cellulose diacetate, cellulose acetate butyrate, cellulose acetate phthalate, cellulose acetate propionate, cellulose triacetate, cellulose nitrate, or derivatives thereof, polyethylene terephthalate, polyethylene naphthalate, etc. Polyester, polyvinylidene chloride, polyvinyl alcohol, ethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyether sulfone, polysulfone, polyether ketoneimide, polyamide, fluororesin, nylon, Examples thereof include a film containing acrylic such as polymethylmethacrylate or polyarylate as a main component resin.

When the resin film (A) is a multi-layer film, it is preferable that the acrylic resin layer / alicyclic structural resin layer / acrylic resin layer, the acrylic resin layer / cyclic olefin resin layer / acrylic resin layer, and the alicyclic structural resin layer. / Polycarbonate resin layer / alicyclic structural resin layer, or a multi-layer film having a laminated structure such as an alicyclic structural resin layer / acrylic resin layer / alicyclic structural resin layer can be mentioned.

Among them, a multi-layer film having an acrylic resin layer as the outermost surface layer is preferable.
In particular, a three-layer film composed of an acrylic resin layer / alicyclic structural resin layer / acrylic resin layer is preferable.

(Acrylic resin layer)
The acrylic resin layer may be a layer containing the acrylic polymer described below as a main component resin. Therefore, the acrylic resin layer may contain a resin component other than the acrylic polymer, or may contain a component other than the resin.
However, since the main component resin of the acrylic resin layer is an acrylic polymer, it is preferable that the acrylic polymer accounts for 50% by mass or more of the resin contained in the acrylic resin layer, particularly 80% by mass or more, and 90% by mass or more among them. It is particularly preferable that the acrylic polymer accounts for% or more (including 100% by mass).

Specifically, the acrylic resin layer may contain, for example, an ultraviolet absorber, a silane coupling agent, an antioxidant, a weather stabilizer, a flexibility modifier, and various other additives in an appropriate amount.

The flexibility modifier is not particularly specified. Examples thereof include rubber elastic fine particles and soft resins. From the viewpoint of transparency and optical properties, it is preferable to select a soft resin as a flexibility modifier.
Examples of the soft resin include the product name "Clarity" manufactured by Kuraray Co., Ltd. and the product name "NANOSTRENGTH" manufactured by Arkema Co., Ltd.

From the viewpoint of flexibility, the flexibility modifier is preferably contained in an amount of 1% by weight or more, more preferably 5% by weight or more, based on the acrylic polymer in the acrylic resin layer. It is more preferably contained in an amount of% by weight or more. The upper limit of the content of the flexibility modifier is not particularly specified, but is usually 50% by weight or less.

(Acrylic polymer)
The acrylic polymer forming the main component resin of the acrylic resin layer may be a polymer containing acrylic acid, methacrylic acid or a derivative thereof as a monomer component. Of these, an acrylic polymer as a thermoplastic resin is preferable.

Examples of the acrylic monomer constituting the acrylic polymer include methyl methacrylate, methacrylic acid, acrylic acid, benzyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, and t-. Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, glycidyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2-methoxyethyl ( Meta) acrylate, 2-ethoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, norbornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclo Penthenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acrylic (meth) acrylate, 2-hydroxyethyl (meth) acrylate, -2- (meth) acroyloxyethyl succinate, -2-maleate -2- ( Meta) acroyloxyethyl, -2- (meth) acroyloxyethyl, -2- (meth) acryoleoxyethyl, pentamethylpiperidyl (meth) acrylate, tetramethylpiperidyl (meth) acrylate , Dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate and the like can be exemplified. These may be polymerized alone or may be used by copolymerizing two or more kinds. Further, it may be a copolymer with one or more kinds of other monomers copolymerizable with these acrylic monomers, such as polyolefin monomers and vinyl monomers. ..

In addition, in this specification, "(meth) acrylic" means that both "acrylic" and "methacryl" are included. The same applies to "(meta) acrylate" and "(meta) acryloyl".

The molecular weight of the acrylic polymer is not particularly limited. For example, if the weight average molecular weight is in the range of 30,000 or more and 300,000 or less, it is possible to provide a film having excellent mechanical properties and heat resistance without causing appearance defects such as flow unevenness during molding.

The glass transition temperature of the acrylic polymer measured at a heating rate of 10 ° C./min according to JIS K7122 is not particularly limited. For example, from the viewpoint of heat resistance of the obtained film, 80 ° C. or higher is preferable, 90 ° C. or higher is more preferable, and 100 ° C. or higher is even more preferable.
The upper limit of the glass transition temperature of the acrylic polymer is not particularly specified. However, it is usually about 140 ° C. Further, when the glass transition temperature of the acrylic polymer is less than 120 ° C., a general-purpose resin can be used, which is preferable from the viewpoint of expanding the selection range of raw materials. On the other hand, when higher heat resistance is required, the glass transition temperature is preferably 120 ° C. or higher.

The MFR, which is an index of the melt viscosity of the acrylic polymer, is a value measured at a temperature of 230 ° C. and a load of 37.27 N in accordance with JIS-K7210, and is usually 1.0 g / 10 min or more and 50 g / 10 min or less. Of these, 5 g / 10 min or more or 30 g / 10 min or less, and more preferably 8 g / 10 min or more or 20 g / 10 min or less.

(Alicyclic structural resin layer)
As the layer contained in the resin film (A) at least one layer, instead of the acrylic resin layer, it has the same transparency as the acrylic resin, has low double refractive index, and has low water absorption, and has low water absorption. Since the heat resistance is stronger than that of the acrylic resin, the alicyclic structure layer containing the alicyclic structure-containing polymer as a main component can be adopted. The alicyclic structure resin layer may contain a resin component other than the alicyclic structure-containing polymer, or may contain a component other than the resin.
However, since the main component resin of the alicyclic structural resin layer is an alicyclic structure-containing polymer, the alicyclic structure-containing polymer accounts for 50% by mass or more of the resin contained in the alicyclic structural resin layer. It is particularly preferable that the alicyclic structure-containing polymer occupies 80% by mass or more, and 90% by mass or more (including 100% by mass) among them.

Specifically, the alicyclic structural resin layer may contain, for example, an ultraviolet absorber, a silane coupling agent, an antioxidant, a weathering stabilizer, and various other additives in an appropriate amount.

As the ultraviolet absorber, known ones, for example, various commercially available ones can be used without particular limitation. Among them, those that can be usually used for addition to known aromatic polycarbonate resins can be preferably used.

Examples of the ultraviolet absorber include 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole and 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzo. Triazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole and 2,2'- Benzotriazole-based UV absorbers such as methylenebis (4-cumyl-6-benzotriazole phenyl); Benzotriazole-based UV absorbers such as 2,2'-p-phenylenebis (1,3-benzoxazine-4-one) A hydroxyphenyltriazine-based ultraviolet absorber such as 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5- (hexyl) oxy-phenol; and the like can be mentioned.

The melting point of the ultraviolet absorber is particularly preferably in the range of 120 ° C. or higher and 250 ° C. or lower. When an ultraviolet absorber having a melting point of 120 ° C. or higher is used, the film surface becomes dirty due to the bleed-out phenomenon in which the ultraviolet absorber aggregates on the film surface over time, or when the film is molded using a mouthpiece or a metal roll. Bleed-out prevents them from becoming dirty and makes it easier to reduce and improve fogging on the film surface.

From these viewpoints, the ultraviolet absorbers include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-. 5-Chlorobenzotriazole, 2- [2'-hydroxy-3'-(3 ", 4", 5 ", 6" -tetrahydrophthalimidemethyl) -5'-methylphenyl] benzotriazole, 2,2-methylenebis [ 4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl)] phenol and 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole, etc. Benzotriazole-based UV absorbers and hydroxyphenyltriazine-based UV absorbers such as 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5- (hexyl) oxy-phenol are preferably used. can.

Among these, 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzo) Triazole-2-yl)] Phenol, 2- (4,6-diphenyl-1,3,-triazine-2-yl) -5- (hexyl) oxy-phenol is particularly preferred.
These ultraviolet absorbers may be used alone or in combination of two or more.

The ultraviolet absorber is preferably added at a ratio of 0.0001 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the alicyclic structure-containing polymer in the alicyclic structure resin layer. It is more preferable to add at a ratio of 0005 parts by weight or more and 15 parts by weight or less, and further preferably at a ratio of 0.001 parts by weight or more and 10 parts by weight or less.
By adding the ultraviolet absorber in such a range, the weather resistance of the film can be improved without causing bleeding of the ultraviolet absorber or deterioration of mechanical properties on the surface of the alicyclic structural resin layer.

(Alicyclic structure-containing polymer)
The alicyclic structure-containing polymer forming the main component resin of the alicyclic structure layer may be a polymer having an alicyclic structure in the repeating unit of the polymer, for example, having an alicyclic structure in the main chain. It may be either a polymer or a polymer having an alicyclic structure on the side chain.

The alicyclic structure-containing polymer may be contained alone or in combination of two or more in any ratio. Above all, a polymer having an alicyclic structure in the main chain is preferable from the viewpoint of mechanical strength, heat resistance and the like.

Examples of the alicyclic structure include a saturated alicyclic hydrocarbon (cycloalkane) structure and an unsaturated alicyclic hydrocarbon (cycloalkene, cycloalkyne) structure. Among them, a cycloalkane structure and a cycloalkene structure are preferable, and a cycloalkane structure is particularly preferable, from the viewpoints of mechanical strength, heat resistance and the like.

The number of carbon atoms constituting the alicyclic structure is preferably 4 or more, more preferably 5 or more, preferably 30 or less, more preferably 20 or less, and particularly preferably 20 or less, per one alicyclic structure. 15 or less. When the number of carbon atoms is in this range, mechanical strength, heat resistance, and moldability of the base material layer are highly balanced, which is preferable.

The ratio of the repeating unit having the alicyclic structure in the polymer resin having the alicyclic structure is not particularly limited as long as the glass transition temperature is 80 ° C. or higher. It is usually 30% by weight or more, preferably 50% by weight or more. It is preferable to set the repeating unit having an alicyclic structure in the above range because the heat resistance can be improved and the optical characteristics can be adjusted.

Specific examples of the alicyclic structure-containing polymer resin include (1) a copolymer of cyclic ethers and an alicyclic dihydroxy compound, (2) a norbornene polymer, and (3) a monocyclic cyclic olefin polymer. Examples thereof include (4) cyclic conjugated diene polymers, (5) vinyl alicyclic hydrocarbon polymers, and hydrogenated products thereof. Among these, from the viewpoint of transparency and moldability, copolymers of cyclic ethers and alicyclic dihydroxy compounds, which will be described later, norbornene polymers, and hydrogenated products thereof are more preferable.

(1) Polymer of cyclic ethers and alicyclic dihydroxy compound As an alicyclic structure-containing polymer, the alicyclic structure is particularly provided with high transparency, high strength, high heat resistance, high weather resistance and the like. It is preferably a polymer containing another structure for the purpose of imparting. Among them, those having an aliphatic polycarbonate skeleton are preferable, and in particular, a polycarbonate resin containing a structural unit derived from a dihydroxy compound having a site represented by the following formula (1) in a part of the structure is preferable.

More specifically, examples of the dihydroxy compound represented by the above formula (1) include isosorbide, isomannide and isoidet, which are in a stereoisomeric relationship.

The dihydroxy compound represented by the formula (1) is an ether diol that can be produced from a sugar using a biological substance as a raw material. In particular, isosorbide can be inexpensively produced by hydrogenating D-glucose obtained from starch and then dehydrating it, and can be abundantly available as a resource. Due to these circumstances, isosorbide is most preferable as the dihydroxy compound represented by the above formula (1).

The polycarbonate resin as the alicyclic structure-containing polymer has a structural unit other than the structural unit derived from the dihydroxy compound having a site represented by the formula (1) and a structure derived from the dihydroxy compound having the alicyclic structure. It is a polymer containing a unit.

More specifically, for example, a structural unit derived from the alicyclic dihydroxy compound described in International Publication No. 2007/148604 can be mentioned.

Among the structural units derived from the alicyclic dihydroxy compound, those containing a 5-membered ring structure or a 6-membered ring structure are preferable. The 6-membered ring structure may be fixed in a chair or boat shape by covalent bonds.

By including a structural unit derived from an alicyclic dihydroxy compound having a 5-membered ring structure or a 6-membered ring structure, the heat resistance of the obtained polycarbonate resin can be increased.

The number of carbon atoms contained in the alicyclic dihydroxy compound is usually preferably 70 or less, more preferably 50 or less, and further preferably 30 or less.

Examples of the alicyclic dihydroxy compound containing the 5-membered ring structure or the 6-membered ring structure include those described in International Publication No. 2007/148604 described above.

Among them, cyclohexanedimethanol, tricyclodecanedimethanol, adamantanediol and pentacyclopentadecanedimethanol can be preferably exemplified. Among these, cyclohexanedimethanol or tricyclodecanedimethanol is more preferable from the viewpoint of economy and heat resistance. In particular, it is most preferable to contain a structural unit derived from tricyclodecanedimethanol represented by the following formula (2) in terms of economy, heat resistance, and a balance with optical properties.

As for these other structural units, only one type may be contained in the polycarbonate resin, or two or more types may be contained.

The content ratio of the structural unit derived from the dihydroxy compound having a portion represented by the formula (1) in a part of the structure of the polycarbonate resin is based on the structural unit derived from all the dihydroxy compounds in the polycarbonate resin. It is preferably 30 mol% or more, more preferably 40 mol% or more, particularly preferably 50 mol% or more, and preferably 90 mol% or less, more preferably 80 mol% or less.

When the content ratio of the structural unit derived from the dihydroxy compound having a portion represented by the formula (1) in a part of the structure of the polycarbonate resin is equal to or higher than the above lower limit, the heat resistance is improved by maintaining the glass transition temperature. Is preferable because it enables. On the other hand, when it is not more than the above upper limit, it is possible to suppress coloring derived from the carbonate structure, coloring derived from impurities contained in a trace amount because a biological substance is used as a raw material, and the like, which is usually required for the base material layer. May not compromise transparency. Further, appropriate molding processability, mechanical strength and heat resistance, which are difficult to achieve with a polycarbonate resin or the like composed of only structural units derived from a dihydroxy compound having a portion represented by the above formula (1) in a part of the structure. It is possible to balance gender and the like.

The polycarbonate resin is composed of a structural unit derived from a dihydroxy compound having a site represented by the formula (1) in a part of the structure, a structural unit derived from an alicyclic dihydroxy compound, and an aliphatic hydroxy compound. However, structural units derived from other dihydroxy compounds may be further contained as long as the object of the present invention is not impaired.

The polycarbonate resin can be produced by a polymerization method that can be generally used. The method for producing the polycarbonate resin may be either a phosgene method or a transesterification method in which the polycarbonate resin is reacted with a carbonic acid diester. Among them, a dihydroxy compound having a site represented by the above formula (1) in a part of the structure in the presence of a polymerization catalyst, an alicyclic compound and an aliphatic dihydroxy compound, and other compounds which can be used as needed. A transesterification method in which the dihydroxy compound is reacted with the carbonic acid diester is preferable.

The transesterification method requires one or more dihydroxy compounds having a site represented by the above formula (1) in a part of the structure, and one or more dihydroxy compounds of the alicyclic type and dihydroxy compounds. Production in which a transesterification reaction is carried out by adding a basic catalyst and an acidic substance that neutralizes the basic catalyst to one or more of other dihydroxy compounds that can be used depending on the situation and a carbonic acid diester. The method.

Typical examples of carbonic acid diesters include diphenyl carbonate, ditril carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carnate, bis (biphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate and dicyclohexyl carbonate. Can be mentioned. One of these may be used alone, or two or more thereof may be mixed and used. Of these, diphenyl carbonate can be particularly preferably used.

The molecular weight of the polycarbonate resin can be expressed by the reduced viscosity. If the reducing viscosity of the polycarbonate resin is too low, the mechanical strength of the molded product may be small, and conversely, if it is too large, the fluidity during molding tends to decrease, which tends to reduce productivity and moldability. ..
From this point of view, the lower limit of the reducing viscosity of the polycarbonate resin is preferably 0.20 dl / g or more, more preferably 0.30 dL / g or more, further preferably 0.35 dL / g or more, and the upper limit of the reducing viscosity is 2. It is preferably 00 dL / g or less.

The reduced viscosity of the polycarbonate resin is precisely adjusted so that the polycarbonate resin concentration is 0.60 g / dl using a Ubbelohde type viscometer with a DT-504 type automatic viscometer manufactured by Chuo Rika Co., Ltd. and methylene chloride as a solvent. After adjusting to, the temperature is 20.0 ° C. ± 0.1 ° C., and it is calculated from the measured values based on the following.
From the solvent transit time t0 and the solution transit time t, the following formula:
η _rel = t / t ₀
The relative viscosity η _ll was obtained from the relative viscosity η _ll, and the following formula:
η _sp = (η − η ₀ ) / η ₀ = _ηrel -1
The specific viscosity η _sp is obtained.
Dividing the specific viscosity η _sp by the concentration c (g / dl), the following formula:
η _red = η _sp / c
The reduced viscosity (converted viscosity) η _red is obtained from the above.

(2) Norbornene polymer As the norbornene polymer, for example, a ring-opening polymer of a monomer having a norbornene structure, a ring-opening copolymer of a monomer having a norbornene structure and another monomer, or them. The hydride of the above; an addition polymer of a monomer having a norbornene structure, an addition copolymer of a monomer having a norbornene structure and another monomer, or a hydride thereof; and the like can be mentioned. Among these, the ring-opening (co) polymer hydride of the monomer having a norbornene structure is particularly suitable from the viewpoints of transparency, moldability, heat resistance, low hygroscopicity, dimensional stability, light weight and the like. Is.
In addition, in this specification, "(co) polymer" means a polymer and a copolymer.

Examples of the monomer having a norbornene structure include bicyclo [2.2.1] hept-2-ene (trivial name: norbornene) and tricyclo [4.3.0.12.5] deca-3,7. -Diene (trivial name: dicyclopentadiene), 7,8-benzotricyclo [4.3.0.12.5] deca-3-ene (trivial name: metanotetrahydrofluorene), tetracyclo [4.4.0 .12, 5.17, 10] Dodeca-3-ene (trivial name: tetracyclopentadiene), derivatives of these compounds (for example, those having a substituent on the ring) and the like can be mentioned. Here, examples of the substituent include an alkyl group, an alkylene group, a polar group and the like. Further, these substituents may be the same or different from each other, and a plurality of these substituents may be bonded to the ring. Further, as the monomer having a norbornene structure, one type may be used alone, or two or more types may be used in combination at an arbitrary ratio.

Examples of the type of polar group include a hetero atom or an atomic group having a hetero atom. Examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group and a sulfonic acid group.

Examples of other monomers that can be ring-opened and copolymerizable with a monomer having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene and derivatives thereof; cyclic conjugated diene such as cyclohexadiene and cycloheptadiene. And derivatives thereof; and the like. As the monomer having a norbornene structure and other monomers capable of ring-opening copolymerization, one type may be used alone, or two or more types may be used in combination at any ratio.

The ring-opening polymer of a monomer having a norbornene structure and the ring-opening copolymer of another monomer copolymerizable with the monomer having a norbornene structure are, for example, ring-opening polymerization of known monomers. It may be produced by polymerization or copolymerization in the presence of a catalyst.

Other monomers that can be additionally copolymerized with the monomer having a norbornene structure include α-olefins having 2 to 20 carbon atoms such as ethylene, propylene and 1-butene and derivatives thereof; cyclobutene, cyclopentene, etc. Cycloolefins such as cyclohexene and derivatives thereof; non-conjugated diene such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene; and the like can be mentioned. Among these, α-olefins are preferable, and ethylene is more preferable. Further, as the monomer having a norbornene structure and other monomers that can be additionally copolymerized, one type may be used alone, or two or more types may be used in combination at an arbitrary ratio.

The addition copolymer of a monomer having a norbornene structure and the addition copolymer of a monomer having a norbornen structure and another copolymerizable monomer can be, for example, a monomer of a known addition polymerization catalyst. It may be produced by polymerization or copolymerization in the presence.

(3) Monocyclic Cyclic Olefin Polymer Examples of the monocyclic cyclic olefin polymer include an addition polymer of a cyclic olefin-based monomer having a monocyclic ring such as cyclohexene, cycloheptene, and cyclooctene.

(4) Cyclic conjugated diene copolymer The cyclic conjugated diene polymer is a polymer obtained by cyclizing an addition polymer of a conjugated diene monomer such as 1,3-butadiene, isoprene, and chloroprene; 1,2- or 1,4-additional polymers of cyclic conjugated diene-based monomers such as pentadiene and cyclohexadiene; and hydrides thereof; and the like can be mentioned.

(5) Vinyl alicyclic hydrocarbon polymer Examples of the vinyl alicyclic hydrocarbon polymer include polymers of vinyl alicyclic hydrocarbon-based monomers such as vinylcyclohexene and vinylcyclohexane and hydrides thereof; styrene and α. − A hydride obtained by hydrogenating the aromatic ring portion contained in the polymer obtained by polymerizing a vinyl aromatic hydrocarbon-based monomer such as methylstyrene; a vinyl alicyclic hydrocarbon-based monomer or a vinyl aromatic hydrocarbon-based monomer. And hydrides of aromatic rings of copolymers such as random copolymers or block polymers with other monomers copolymerizable with these vinyl aromatic hydrocarbon-based monomers. Examples of the block copolymers include diblock copolymers, triblock copolymers or higher multi-block copolymers, inclined block copolymers, and the like.

As a film forming method for the resin film (A), a known method such as a single-screw extruder, a multi-screw extruder, a Banbury mixer, a kneader or the like is provided, and an extrusion casting method or a calendar method using a T-die is provided. However, in the present invention, an extrusion casting method using a T-die can be preferably used from the viewpoints of handleability and productivity.
The molding temperature in the extrusion casting method using a T-die is appropriately adjusted depending on the flow characteristics and film-forming properties of the polymer used, but is generally 80 ° C. or higher, preferably 100 ° C. or higher, more preferably 120 ° C. or higher, and further. It is preferably 140 ° C. or higher and approximately 320 ° C. or lower, preferably 300 ° C. or lower, more preferably 280 ° C. or lower, still more preferably 260 ° C. or lower, and when a silane coupling agent or the like is added, it accompanies the reaction. It is preferable to lower the molding temperature in order to suppress an increase in resin pressure and an increase in fish eyes. Various additives such as a silane coupling agent, an antioxidant, an ultraviolet absorber, and a weather-resistant stabilizer may be dry-blended together with an alicyclic structure-containing polymer such as a polycarbonate resin in advance and then supplied to the hopper. All the materials of the polymer may be melt-mixed in advance to prepare pellets and then supplied, or a master batch in which only the additives are concentrated in resin in advance may be prepared and supplied.

<Easy adhesive layer (B)>
The easy-adhesion layer (B) has a role of facilitating the adhesion of the resin film (A) to other members.

As described above, the polarizing plate is generally formed by laminating protective films on both sides of the polarizing element using a water-soluble adhesive such as polyvinyl alcohol. Therefore, when the resin film (A) is used as the protective film, the easy-adhesion layer (B) improves the adhesiveness of such a water-soluble adhesive and has adhesiveness to the resin film (A). It is preferable that the one that can secure the above.
Therefore, for example, when the resin film (A) is a single-layer film composed of an acrylic resin layer or an alicyclic structural resin layer as described above, or when the acrylic resin layer or the alicyclic structural resin layer is used as the outermost surface layer. Assuming that the resin film (A) is attached to the polarizer using a water-soluble adhesive, the easy-adhesion layer (B) is an acrylic resin layer. It is preferable that the resin layer has an alicyclic structure and is well-adapted to the above-mentioned water-soluble adhesive and can exhibit high adhesion.

From this point of view, the resin composition constituting the easy-adhesion layer (B) is preferably a resin composition that can be adhered to the PVA film using a water-soluble adhesive, and among them, a urethane group and an amide group. , A resin composition containing a polymer having an NCO group as a main component is preferable, and a resin composition containing a urethane-based resin as a main component is particularly preferable.

Examples of the urethane resin include (1) a component containing an average of two or more active hydrogens in one molecule (hereinafter, may be referred to as "component (1)") and (2) a multivalent isocyanate component (2). Urethane resin obtained by reacting with "component (2)" hereafter; or, the above component (1) and component (2) are inactive in the reaction under the condition of excess isocyanate group. Isocyanate group-containing prepolymer by urethanization reaction in an organic solvent having a high affinity with water, then the prepolymer is neutralized, the chain is extended with a chain extender, and water is added to the dispersion. Urethane-based resin produced by the above; and the like. These urethane resins may contain an acid structure (acid residue).

A known method can be adopted as the chain extension method of the isocyanate group-containing prepolymer. For example, water, a water-soluble polyamine, glycols and the like are used as the chain extender, and the isocyanate group-containing prepolymer and the chain extender are used. May be reacted in the presence of a catalyst, if necessary.

The component (1) is not particularly limited, and among them, a compound having a hydroxyl group of active hydrogen is preferable. Specific examples of such compounds include those exemplified in the following (1-1) to (1-5).

(1-1) Glycol Compound Examples of the polyol compound include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, and 1,4-. Butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 2,5-hexanediol, 1,8-octanediol, dipropylene glycol, 2,2,4-trimethyl-1,3 -Pentanediol, tricyclodecanedimethanol, 1,4-cyclohexanedimethanol, 2,2-dimethylpropanediol and the like can be mentioned.

(1-2) Polyether polyol As the polyether polyol, for example, an alkylene oxide adduct of the polyol compound of (1-1) above; a ring-opening (co) polymer of an alkylene oxide and a cyclic ether (for example, tetrahydrofuran); Copolymers of polyethylene glycol, polypropylene glycol, ethylene glycol-propylene glycol; glycols such as glycol, polytetramethylene glycol, polyhexamethylene glycol, and polyoctamethylene glycol; and the like.

(1-3) Polyester polyol As the polyester polyol, for example, a dicarboxylic acid such as adipic acid, succinic acid, sebacic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid or an anhydride thereof, and the above (1-1). Obtained by polycondensing the above-mentioned polyol compounds such as ethylene glycol, propylene glycol, 1,4-butylene glycol, 1,6-hexanediol, 1,8-octanediol, and neopentyl glycol under the condition of excess hydroxyl group. Can be mentioned. More specifically, for example, ethylene glycol-adipic acid condensate, butanediol-adipine condensate, hexamethylene glycol-adipic acid condensate, ethylene glycol-propylene glycol-adipic acid condensate, or lactone using glycol as an initiator. Examples thereof include polylactone diols obtained by ring-opening polymerization of.

(1-4) Polyether Ester Polyester As the polyether ester polyol, for example, an ether group-containing polyol (for example, the polyether polyol or diethylene glycol of (1-2) above) or a mixture thereof and other glycol is used as described above. Examples thereof include those obtained by reacting an alkylene oxide with a dicarboxylic acid or an anhydride thereof as exemplified in (1-3). More specifically, for example, a polytetramethylene glycol-azipic acid condensate can be mentioned.

(1-5) Polycarbonate Polyol As the polycarbonate polyol, for example, the general formula HO-R- (OC (O) -OR) n-OH (however, in the formula, R has 1 or more carbon atoms and 12 or less carbon atoms). In addition, n indicates the number of repeating units of the molecule, and is usually an integer of 5 or more and 50 or less). These are transesterification methods in which a saturated aliphatic polyol and a substituted carbonate (for example, diethyl carbonate, diphenyl carbonate, etc.) are reacted under conditions where the hydroxyl group becomes excessive; the saturated aliphatic polyol is reacted with phosgen, or If necessary, it can be obtained by a method of further reacting a saturated aliphatic polyol; or the like.

As the compounds exemplified in the above (1-1) to (1-5), one kind may be used alone, or two or more kinds may be used in combination at an arbitrary ratio.

Examples of the component (2) to react with the component (1) include aliphatic, alicyclic or aromatic compounds containing an average of two or more isocyanate groups in one molecule.

The aliphatic diisocyanate compound is preferably an aliphatic diisocyanate having 1 to 12 carbon atoms, and examples thereof include hexamethylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, and hexane diisocyanate (HDI). As the alicyclic diisocyanate compound, an alicyclic diisocyanate compound having 4 to 18 carbon atoms is preferable, and for example, 1,4-cyclohexanediisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI) and the like. Can be mentioned. Examples of the aromatic diisocyanate compound include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylene diisocyanate. One of these may be used alone, or two or more of them may be used in combination at any ratio.

The urethane-based resin that forms the main component resin of the easy-adhesion layer (B) is excellent in heat resistance and water resistance, and can form an easy-adhesion layer having the optimum storage elasticity in the present invention. Therefore, it is an aliphatic polycarbonate. Those having a skeleton, specifically, a urethane resin obtained by reacting the polycarbonate polyol (1-5) described above with an aliphatic diisocyanate compound and / or an alicyclic diisocyanate compound are preferable.

The urethane resin preferably has an acid structure. A urethane-based resin having an acid structure can be dispersed in water without using a surfactant or even if the amount of the surfactant is small, so that the water resistance of the easy-adhesion layer is improved. There is expected. This is called a self-emulsifying type, and means that the urethane-based resin can be dispersed and stabilized in water only by molecular ionicity without using a surfactant. The easy-adhesion layer (B) using such a urethane-based resin is preferable because it has excellent adhesion to the release film (C) and can maintain high transparency. Further, it is preferable to carry out cross-linking starting from this acid structure because the hydrophobicity, heat resistance and moist heat resistance can be further improved.

Examples of the acid structure include acid groups such as a carboxyl group (-COOH) and a sulfonic acid group (-SO3H). Further, the acid structure may be present in the side chain of the urethane resin or may be present at the end. As the acid structure, one type may be used, or two or more types may be used in combination at an arbitrary ratio.

As for the content of the acid structure, the acid value of the urethane resin is preferably 5 mgKOH / g or more, more preferably 10 mgKOH / g or more, preferably 250 mgKOH / g or less, and more preferably 150 mgKOH / g or less. If the acid value is less than 5 mgKOH / g, the water dispersibility tends to be insufficient, while if the acid value is larger than 250 mgKOH / g, the water resistance of the easy-adhesion layer tends to be inferior.

As a method for introducing an acid structure into a urethane-based resin, a conventionally used method can be used without particular limitation. To give a preferred example, a polyether polyol, a polyester polyol, or a polyether ester is prepared in advance by replacing dimethylol alkanoic acid with a part or all of the glycol components described in (1-2) to (1-4) above. Examples thereof include a method of introducing a carboxyl group into a polyol or the like. Examples of the dimethylol alkanoic acid that can be used here include dimethylol acetic acid, dimethylol propionic acid, and dimethylol butyric acid. One type of dimethylolalkanoic acid may be used alone, or two or more types may be used in combination at an arbitrary ratio.

The number average molecular weight of the urethane resin is preferably 1,000 or more, more preferably 20,000 or more, preferably 1,000,000 or less, and more preferably 200,000 or less.

A commercially available urethane resin may be used.
Commercially available urethane-based resins that can be used for coating as an easy-adhesion layer include, for example, the "Adeka Bontita" series manufactured by Asahi Denka Kogyo Co., Ltd., the "Orestar" series manufactured by Mitsui Toatsu Chemical Co., Ltd., and Dainippon Ink. "Bondic" series, "Hydran" series manufactured by Kagaku Kogyo Co., Ltd., "Implanil" series manufactured by Bayer Co., Ltd., "Sofranate" series manufactured by Nippon Soflan Co., Ltd., "Poise" series manufactured by Kao Corporation, Sanyo Kasei Kogyo Co., Ltd. "Samplen", "Ucoat", "Eupolin" series, "Resamine" series manufactured by Dainichiseika Kogyo Co., Ltd., "Aizelux" series manufactured by Hodogaya Chemical Co., Ltd., "Superflex" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. The series, the "Neolets" series manufactured by Zeneka, the "Sancure" series manufactured by Lubrizol, the "RU" series manufactured by Stahl Japan, and the like can be used. In particular, "Ucoat UA-368" manufactured by Sanyo Chemical Industries, Ltd., "RU-40-350" and "EX-RU-92-605" manufactured by Stahl Japan Co., Ltd., and "Resamine D" manufactured by Dainichiseika Kogyo Co., Ltd. "-6031" and the like have an aliphatic polycarbonate skeleton and are water-dispersed by a volatile base, so that there is little residual substance and it is suitable.

When a urethane-based resin is used as the main component resin of the easy-adhesion layer (B), the easy-adhesion layer (B) is crosslinked as necessary for the purpose of improving moisture resistance, heat resistance, and mechanical strength. The agent may be contained.
As the cross-linking agent, generally, a carbodiimide resin, an epoxy resin, an oxazoline resin, a melamine resin, an isocyanate resin and the like can be preferably used.
The content of the cross-linking agent is 0.1 parts by weight or more with respect to 100 parts by weight of the urethane-based resin. It is preferable from the viewpoint of sufficiently increasing the target strength. On the other hand, from the viewpoint of reducing the residual unreacted cross-linking agent and increasing the moisture resistance, heat resistance, and mechanical strength of the easy-adhesion layer (B), the cross-linking agent is 40 parts by weight with respect to 100 parts by weight of the urethane resin. It is preferably less than. It is particularly preferable that the amount is 1 part by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the urethane resin.

When the urethane-based resin is used as the main component resin of the easy-adhesion layer (B), the viscosity adjustment, drying speed, and drying in the molding process of the easy-adhesion layer are not impaired as long as the stability and performance of the urethane-based resin are not impaired. It is preferable to add various solvents individually or in combination for the purpose of adjusting the temperature. As the solvent in the urethane resin that can be used in the above-mentioned coating and the like, in addition to ion-exchanged water and distilled water, alcohol-based solvents and various organic solvents can be used. Among them, alcohols such as methanol, ethanol, and isopropanol are highly volatile, can reduce the drying temperature and drying time, and are also excellent in compatibility with urethane resins for coating, so that they can be suitably used.

The thickness of the easy-adhesion layer (B) is preferably 0.3 μm or more and 2.5 μm or less. If it is 0.3 μm or more, it is preferable because the adhesiveness can be improved when it is bonded to the PVA film using a water-soluble adhesive. On the other hand, if it is 2.5 μm or less, the tack on the easy-adhesion layer side is tackled. It is preferable because the increase in properties can be suppressed and the delamination strength F2 with the release film (C) can be 1.0 or less.
From this point of view, the thickness of the easy-adhesion layer (B) is preferably 0.3 μm or more and 2.5 μm or less, more preferably 0.5 μm or more or 2.0 μm or less, and particularly 0.7 μm. It is more preferably more than or less than 1.5 μm.
When the above-mentioned coating method is used as the method for adjusting the thickness of the easy-adhesion layer (B), the solid content of the resin composition forming the easy-adhesion layer (B) is adjusted, or the coating amount is adjusted. It is possible to do it by doing something like that. However, the method is not limited to these methods.

The easy-adhesion layer (B) preferably has a storage elastic modulus G'(MPa) at 23 ° C. of 0.1 or more and 100 or less, more preferably 0.5 MPa or more or 90 MPa or less, and 1 MPa or more or It is more preferably 80 MPa or less.
By setting the storage elastic modulus of the easy-adhesion layer (B) at 23 ° C. to 0.1 MPa or more, an increase in tackiness on the easy-adhesion layer side is suppressed, and the release film (C) and the easy-adhesion layer (B) The delamination strength F2 can be suppressed to 1.0 or less. On the other hand, when the pressure is 100 MPa or less, the adhesiveness can be enhanced when the PVA film is bonded to the PVA film using a water-soluble adhesive.
The storage elastic modulus of the easy-adhesion layer (B) can be adjusted by changing the type and composition of the resin constituting the easy-adhesion layer to be used. However, the method is not limited to these methods.

<Release film (C)>
The release film (C) is preferably one that can be easily peeled off from the resin film (A) while improving the handleability by laminating it on the resin film (A). Among them, for example, a film that can be used as a protective film (so-called masking film) for a polarizer protective film is preferable.

The release film (C) is a multi-layer film having a base material layer C1 and an adhesive layer C2. Specifically, the adhesive layer C2 is provided on one side of the base material layer C1. When the release film (C) has the adhesive layer C2, the delamination strength F1 between the resin film (A) and the release film (C) can be 0.01 or more, and the release film (C) can be peeled off. Can be pasted together.

The base material layer C1 of the release film (C) is such that the base material layer C1 and the easy-adhesion layer (B), which are in contact with each other in the present film winding layer, are in contact with each other. In that case, the correlated peel strength F2 between the release film (C) and the easy-adhesion layer (B) is larger than that of F1, but it is important to select so that F2 is 1.0 or less.
For example, as the base material layer C1, polyolefins such as polyethylene, polypropylene and polyvinyl chloride, polyesters such as PET and PEN, polycarbonate (PC), polyimide and the like can be exemplified. Among them, a film using a polyolefin resin such as polyethylene or polypropylene is preferable from the viewpoint of chemical affinity with the adhesive layer C2 and productivity of the release film. However, it is not limited to these.
From the viewpoint of chemical affinity with the adhesive layer C2 and the productivity of the release film, a film using a polyolefin resin such as polyethylene or polypropylene is particularly preferable.

The thickness of the base material layer C1 is preferably 3 μm or more and 100 μm or less. If it is 3 μm or more, it is preferable because the handleability is good, while if it is 100 μm or less, it is preferable because it is economical and the bulk and weight of the wound layer can be reduced.
From this point of view, the thickness of the base material layer C1 is preferably 3 μm or more and 100 μm or less, more preferably 5 μm or more or 80 μm or less, and particularly preferably 10 μm or more or 60 μm or less.

On the other hand, the adhesive layer C2 of the release film (C) can be detachably bonded to the resin film (A) because the adhesive layer C2 and the resin film (A) that are in contact with each other in the film winding layer are in contact with each other. It is important to be able to do it. Examples of the pressure-sensitive adhesive layer C2 include rubber-based pressure-sensitive adhesives, acrylic-based pressure-sensitive adhesives, polyvinyl ether-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives. More specifically, for example, those using an acrylic resin, a urethane resin, an ethylene / vinyl acetate copolymer resin, a polyolefin resin, or the like can be exemplified. However, it is not limited to these.

The thickness of the adhesive layer C2 is preferably 0.1 μm or more and 20 μm or less. When it is 0.1 μm or more, it is preferable because the adhesiveness with the base material layer C1 is good, while when it is 20 μm or less, there is little adhesive residue and the peeling performance with the resin film (A) can be ensured, which is preferable.
From this point of view, the thickness of the adhesive layer C2 is preferably 0.1 μm or more and 20 μm or less, more preferably 0.3 μm or more or 15 μm or less, and particularly 0.5 μm or more or 10 μm or less. Is more preferable.

As the release film (C), for example, an adhesive coating type release film formed by coating a base material layer C1 with an adhesive, or a base material layer C1 and an adhesive layer C2 coextruded and formed. Examples thereof include self-adhesive mold release films. As will be described later, in the present invention, it is preferable that the adhesive layer is a self-adhesive film which is a polyolefin resin layer.

The pressure-sensitive adhesive in the pressure-sensitive adhesive-coated mold release film is not particularly limited as long as it can suppress the occurrence of resin chipping and curl at the time of slitting. For example, an acrylic resin-based adhesive, an epoxy resin-based adhesive, a silicone rubber-based adhesive, and the like can be mentioned. However, it is not limited to these.

The adhesive resin in the self-adhesive release film is not particularly limited as long as it can suppress the occurrence of resin chipping and curl at the time of slitting, but is a self-adhesive release film in which the adhesive layer C2 is a polyolefin resin layer. It is preferable to have.
In the case of a self-adhesive mold release film in which the adhesive layer C2 is a polyolefin resin layer, product contamination due to an outgas component, adhesive residue when peeling the mold release film from the film laminate of the present invention, and a high temperature of 100 ° C. or higher It is suitable because there is little concern that problems such as breakage of the release film and the protective film due to fluctuations in the peeling force caused by component transfer during time may occur.

The method for producing the release film (C) is not particularly limited. For example, a coextrusion method in which a base material layer C1 and an adhesive layer C2 are laminated by coextrusion, a cast coating method in which a base material layer C1 is formed and then an adhesive layer C2 is applied in-line, a base material layer C1 and an adhesive layer C2 Examples include a heat press method in which and are separately formed into a film, and then heat-sealed and laminated. Of these, the coextrusion method is particularly preferable from the viewpoints that there is little concern about product contamination due to volatilization of the residual solvent and that the thickness accuracy is improved.

The correlation peeling strength between the base material layer C1 and the adhesive layer C2 is not particularly limited, but when the release film (C) is peeled from the resin film layer (A), the components of the adhesive layer C2 remain on the resin film. It is important that the release film is peeled off together so that it does not occur.

Further, the release film (C) may have another layer between the base material layer C1 and the adhesive layer C2. Also in this case, when the release film (C) is peeled from the resin film layer (A), it is important that the release film is integrally peeled so that the component of the adhesive layer C2 does not remain on the resin film. be.

The thickness of the release film (C) is preferably 5 μm or more and 100 μm or less. When the thickness of the release film (C) is 5 μm or more, it is preferable because it has good handleability, and when it is 100 μm or less, it is preferable because it is economical and the volume and weight of the wound layer can be reduced.
From this point of view, the thickness of the release film (C) is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more or 80 μm or less, and particularly preferably 15 μm or more or 60 μm or less. ..

<This laminated film>
This laminated film includes a resin film (A) containing at least one layer containing an acrylic polymer, an alicyclic structure-containing polymer, or a mixture of these polymers as a main component resin, and one side of the resin film (A). It is a laminated film provided with an easy-adhesion layer (B) laminated on the surface of the resin film (A) and a release film (C) laminated on the other surface side of the resin film (A) so as to be peelable.

(1) Thickness The thickness of the laminated film is not particularly limited, but is preferably 150 μm or less, more preferably 100 μm or less, and particularly preferably 80 μm or less, from the viewpoint of requesting thinning of the optical film as a whole. On the other hand, from the viewpoint of handleability and strength, 5 μm or more is preferable, and 10 μm or more is more preferable.

(2) Lamination ratio In this laminated film, the ratio (lamination ratio) of the thickness of the release film (C) to the total thickness of the laminated film is 30% or more, more preferably 40% or more, still more preferably 55% or more. ..
Here, when the thickness ratio of the release film (C) is 30% or more, the mechanical strength of the laminated film is good and the handleability is excellent, which is preferable. The upper limit of the thickness of the release film (C) is not particularly defined, but from the viewpoint of reducing the weight of the release film used, it is 95% or less, more preferably 90% or less, still more preferably 85% or less. ..

Hereinafter, a method for producing a laminated film having a layer structure of an easy-adhesion layer (B) / a resin film (A) / a release film (C) will be described, but the method is not particularly limited.
A manufacturing process in which the release film (C) is attached to the resin film (A) and then the easy-adhesion layer (B) is formed can be suitably used from the viewpoint of handleability and productivity.
Hereinafter, a method of laminating the release film (C) and a method of forming the easy-adhesion layer (B) will be described.

The method of laminating the resin film (A) and the release film (C) is not particularly limited, and the films may be laminated and bonded by a roll or the like. At this time, the roll used for bonding is preferably a combination of a rubber roll and a rubber roll or a combination of a rubber roll and a metal roll. Examples of the rubber of the rubber roll include silicone rubber, butyl rubber, EPDM rubber, and nitrile rubber. Of these, silicone rubber is preferable from the viewpoint of durability. As the rubber hardness of the rubber roll, one usually in the range of 20 degrees or more and 90 degrees or less can be used. However, it is not particularly limited.

The molding process of the easy-adhesion layer (B) is a solution coating method in which the resin composition forming the easy-adhesion layer (B) is applied and then the solvent is dried from the viewpoint of productivity and thickness accuracy. Is preferably used. Specific solution coating methods include, for example, wire bar coating method, dip method, spray method, spin coating method, roll coating method, gravure coating method, air knife coating method, curtain coating method, slide coating method, and extrusion coating. The law etc. can be mentioned.

The drying temperature of the easy-adhesion layer (B) during molding depends on the type of solvent contained in the resin composition used, but in general, the easy-adhesion layer can be dried by setting the temperature to 45 ° C. or higher. Therefore, 50 ° C. or higher is more preferable. On the other hand, when the release film (C) having the adhesive layer C2 as the polyolefin-based resin layer is previously bonded to the resin film (A), the drying temperature at the time of molding the easy-adhesion layer (B) is high. The temperature is preferably less than 110 ° C., and more preferably less than 90 ° C. because the performance of the delamination strength of the adhesive layer can be further exhibited. By setting the temperature to less than 110 ° C., it is possible to suppress the delamination strength F1 between the resin film (A) and the release film (C) so as not to be too high.

<Manufacturing method of wound layer>
The method for producing the wound layer of the present invention is not particularly limited, but a known method can be applied, and the wound layer can be produced by laminating the above-mentioned laminate.

<Use>
In the present film winding layer body, the main laminated film obtained by rewinding the winding layer body and processed to a predetermined size is attached to a polarizer via an easy-adhesion layer (B), and then a release film (C) is applied. If it is peeled off, the resin film (A) can be attached to the polarizer as a protective film.
As described above, by adhering the resin film (A) on both the front and back sides of the polarizing element via the easy-adhesion layer (B), it can be used as a polarizing plate that can be used in a liquid crystal display device or the like. can.

When the resin film (A) is attached to the polarizer via the easy-adhesion layer (B), it is preferable to bond the easy-adhesion layer (B) and the polarizer via a water-soluble adhesive such as polyvinyl alcohol. ..
Therefore, a laminated body having a structure in which an adhesive layer containing a water-soluble adhesive such as polyvinyl alcohol as a main component is laminated on the outside of the easy-adhesive layer (B) of the present laminated film constituting the present film winding layer. May be formed and the laminated body may be bonded to the polarizer.

<Explanation of words>
Generally, a "sheet" is a thin product according to the definition in JIS, and its thickness is generally small for its length and width, and is flat. Generally, a "film" is compared to its length and width. A thin flat product with an extremely small thickness and an arbitrarily limited maximum thickness, which is usually supplied in the form of a roll (Japanese Industrial Standard JIS K6900). For example, in terms of thickness, in a narrow sense, a film having a thickness of 100 μm or more may be referred to as a sheet, and a film having a thickness of less than 100 μm may be referred to as a film. However, since the boundary between the sheet and the film is not clear and it is not necessary to distinguish between the two in the present invention, in the present invention, even when the term "sheet" is used, the term "film" is included and the term "film" is used. Even in the case, the "sheet" shall be included.

In the present specification, when expressed as "X or more" (X is an arbitrary number) or "Y or less" (Y is an arbitrary number), it is preferably "greater than X" or "less than Y". It also includes the intention to that effect.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not limited by these Examples and Comparative Examples.

[Evaluation method]
In the following, the measurement and evaluation of various physical properties were carried out as follows.

(Delamination strength between resin film and release film F1)
After cutting the laminated films produced in Examples and Comparative Examples to a width of 20 mm, a test speed of 50 mm / min was used between the resin film and the release film using a universal tensile tester (manufactured by Intesco, model: 200X). T-type peeling was carried out in accordance with the above method, and the delamination strength (F1) (N / 20 mm width) at that time was measured and shown in Table 1.

(Delamination strength between the easy-adhesion layer and the release film F2)
A film sample in which the easy-adhesion layer of the laminated film and the release film are laminated is collected from the wound layers prepared in Examples and Comparative Examples, and this film sample is cut to a width of 20 mm, and then a universal tensile tester is used. (Made by Intesco, model: 200X) was used to perform T-type peeling at a test speed of 50 mm / min, and the delamination strength (F2) (N / 20 mm width) at that time was measured and shown in Table 1.

(Peeling strength between easy-adhesive film and adhesive)
An adhesive is prepared by mixing 0.3 parts by weight of a cross-linking agent (Nippon Synthetic Chem Industry Co., Ltd., SPM-02) with 100 g of a 10% by weight aqueous solution of PVA resin (Nippon Synthetic Chem Industry Co., Ltd., Gosenex Z-200). Made.
With the coated layer of the produced laminated film as the adhesive surface side, an adhesive is applied with a # 24 bar coater, and a biaxially stretched PVA film (manufactured by Nippon Synthetic Chem Industry Co., Ltd., trade name: Boblon, thickness: 40 μm) is bonded. A sample for evaluation was prepared by heating and drying at 100 ° C. for 300 seconds.
After cutting this sample to a width of 20 mm, T-type peeling was performed at a test speed of 50 mm / min using a universal tensile tester (manufactured by Intesco, model: 200X), and the delamination strength (N / 20 mm width) at that time was performed. ) Was measured and shown in Table 1.

(Resin elastic modulus)
Evaluation samples were prepared by applying the coating liquids described in Examples and Comparative Examples to a Teflon (registered trademark) sheet and drying at 100 ° C. for 60 seconds.
This sample was measured by a tensile method using a dynamic viscoelasticity measuring device "DVE-V4" (manufactured by Rheology) at a frequency of 10 Hz and a heating rate of 3 ° C./min to determine the storage elastic modulus at 25 ° C. It is shown in Table 1 as "elastic modulus of the easy-adhesion layer".

<Appearance evaluation>
The film appearance evaluation at the time of unwinding of the wound layer described in Examples and Comparative Examples was carried out and judged under the following conditions.

(Release film release property)
The release film peelability was determined by the following criteria regarding the appearance state when the laminated film and the release film were peeled off after the laminated film was pulled out from the wound layer.
◯: No wrinkles, cracks, or breaks occur on the resin film side when the release film is peeled off.
X: Wrinkles, cracks, and breakage occur on the resin film side when the release film is peeled off.

(State of the surface of the adhesive layer)
Regarding the evaluation of the state of the coat surface, the surface state on the easy-adhesion layer side when the laminated film was unwound from the wound body was judged according to the following criteria.
◯: No damage occurs during unwinding, and no abnormality is found on the surface of the easy-adhesion layer.
X: The resin film is damaged during unwinding. Alternatively, whitening, unevenness, and defects occur on the surface of the easy-adhesion layer of the resin film.

[Manufacturing of polymer]
The resin composition used for the resin film was produced as follows.

<Acrylic polymer>
As the acrylic polymer, a mixed masterbatch of 79 parts by weight of PMMA resin "Sumipex MGSS" manufactured by Sumitomo Chemical Co., Ltd. and 21 parts by weight of acrylic resin "Clarity LA4285" manufactured by Kuraray Co., Ltd. was used. The glass transition temperature (JIS K7122, heating rate 10 ° C./min) of the acrylic polymer was 110 ° C., and the MFR (230 ° C., 3.8 kg load) was 16.0 g / 10 min.

<Alicyclic structure-containing polymer>
It has a structural unit derived from isosorbide, which is a dihydroxy compound, and a structural unit derived from tricyclodecanedimethanol, and the molar ratio of these structural units is isosorbide / tricyclodecanedimethanol = 6/4. An alicyclic structure-containing polymer (polycarbonate resin) having a glass transition temperature of 126 ° C. was prepared.

[Example 1]
A laminated film and a wound layer were produced as follows.

The acrylic polymer and the alicyclic structure-containing polymer (polycarbonate resin) were each put into a φ65 mm single-screw extruder, melt-kneaded at a barrel set temperature of 220 ° C. or higher and 240 ° C. or lower, and had a width of 1350 mm and a lip gap of 0. After co-extruding from a 7 mm base (set temperature 240 ° C.) so as to form a three-layer structure of an acrylic polymer / alicyclic structure-containing polymer / acrylic polymer, the film was cast with a cast roll whose temperature was adjusted to 65 ° C. Then, as the release film (C), the pressure-sensitive adhesive layer side of a 30 μm-thick polypropylene-based self-adhesive film (“Taiko FSA-020M” (manufactured by Futamura Chemical Co., Ltd.) is bonded to the three-layer film to achieve a thickness. A laminated film in which the release film (C) was releasably laminated on one side surface of the 15 μm resin film (A) was produced.

(Preparation of coating liquid)
The coating solution used for the easy-adhesion layer (B) is an aqueous urethane emulsion (acid structure: carboxylic acid, base: triethylamine) "Resamine D-6031" (manufactured by Dainichi Seika Kogyo Co., Ltd., solid content: about 30 wt%) as a urethane resin. , Hereinafter sometimes abbreviated as urethane emulsion (A)), 500 g of methylol / imino-based melamine formaldehyde resin "Simel 701" (manufactured by Ornex Japan Co., Ltd.) as a cross-linking agent, and further 5000 g of isopropanol and methanol are mixed. A coating solution was prepared by diluting with a mixed solution of 5000 g.

(Preparation of laminated film and wound layer)
The resin film (A) side of the produced laminated film, that is, the surface opposite to the release film (C), is corona-treated with a corona treatment device at an integrated irradiation dose of 1000 W / m ² , and then the corona. The treated surface is coated with the coating liquid using a gravure roll so that the thickness of the easy-adhesion layer (B) after drying is 1.2 μm, and the temperature condition is 60 ° C. in a drying furnace having a floating zone of 4 m. By drying under the condition of a line speed of 4 m / min, a laminated film having an easy-adhesion layer (B) having a thickness of 1.2 μm was produced.
Then, this laminated film was wound with a tension of 100 N using an ABS resin core having an inner diameter of 3 inches to prepare a wound layer.

[Example 2]
A laminated film and a wound layer were produced in the same manner as in Example 1 except that the thickness of the easy-adhesion layer (B) was 2.2 μm in Example 1.

[Example 3]
In Example 1, as the release film (C), a PP / PE laminated film "Tretec 7H52" (manufactured by Toray Film Processing Co., Ltd., 30 μm product), which is a laminated film of a polypropylene layer and a polyethylene layer, is used and A laminated film and a wound layer were produced in the same manner as in Example 1 except that the drying temperature after coating when forming the easy-adhesion layer (B) was set to 100 ° C.

[Example 4]
In Example 3, as a coating liquid used for the easy-adhesion layer (B), 9000 g of urethane emulsion (A) and an aqueous urethane emulsion (acid structure: carboxylic acid, base: triethylamine) "Resamine D-6300" (Dainichi Seisakusho) A laminated film and a wound layer were prepared in the same manner as in Example 3 except that a mixed solution of 1000 g of a urethane emulsion (B) manufactured by Kogyo Co., Ltd., solid content: about 30 wt%, hereinafter abbreviated as urethane emulsion (B)) was used. bottom.

[Example 5]
In Example 1, the release film (C) was implemented except that the PP / PE laminated film "Tretec 6030M" (manufactured by Toray Film Processing Co., Ltd., 30 μm product), which is a laminated film of a polypropylene layer and a polyethylene layer, was used. A laminated film and a wound layer were produced in the same manner as in Example 3.

[Example 6]
In Example 1, the above-mentioned acrylic polymer was put into a φ65 mm single-screw extruder, melt-kneaded at a barrel set temperature of 220 ° C. or higher and 240 ° C. or lower, and a base having a width of 1350 mm and a lip gap of 0.7 mm (set temperature 240 ° C.). ), A laminated film and a wound layer were prepared in the same manner as in Example 1 except that the acrylic polymer was extruded into a single layer.

[Example 7]
In Example 1, the alicyclic structure-containing polymer (polycarbonate resin) was put into a φ65 mm single-screw extruder, melt-kneaded at a barrel set temperature of 220 ° C. or higher and 240 ° C. or lower, and had a width of 1350 mm and a lip gap of 0. A laminated film and a wound layer were produced in the same manner as in Example 1 except that the polymer (polycarbonate resin) containing an alicyclic structure was extruded from a 7 mm base (set temperature 240 ° C.) so as to form a single layer.

[Comparative Example 1]
In Example 4, the laminated film and winding were the same as in Example 4, except that the polypropylene-based self-adhesive film "Taiko FSA-020M" (manufactured by Futamura Chemical Co., Ltd., 30 μm product) was used as the release film (C). A layer was prepared.

[Comparative Example 2]
In Example 1, a laminated film and a wound layer were produced in the same manner as in Example 1 except that the thickness of the easy-adhesion layer (B) was 0.1 μm.

[Comparative Example 3]
In Example 3, a laminated film and a wound layer were prepared in the same manner as in Example 3 except that 5000 g of urethane emulsion (A) and 5000 g of urethane emulsion (B) were mixed as the urethane resin of the coating liquid. ..

[Comparative Example 4]
A laminated film and a wound layer were produced in the same manner as in Example 1 except that the thickness of the easy-adhesion layer (B) was set to 2.8 μm in Example 3.

Table 1 shows the evaluation results of the rolled layers in Examples 1 to 7 and Comparative Examples 1 to 4.

As shown in Table 1, it was confirmed that the release films (C) of the wound layers of Examples 1 to 7 had good peelability and no wrinkles or tears occurred. In addition, the easy-adhesive layer (the surface of B also had no abnormalities such as whitening or defects, and good results were obtained. Further, all of them showed very excellent adhesiveness to the water-soluble adhesive.
On the other hand, all of the wound layers of Comparative Examples 1 to 4 were inferior in any of the above characteristics.

Claims (14)

It is formed by laminating a resin film (A) containing at least one layer containing an acrylic polymer, an alicyclic structure-containing polymer, or a mixture of these polymers as a main component resin on one surface side of the resin film (A). A laminated film including an easy-adhesion layer (B) as the outermost layer and a release film (C) that is detachably laminated on the other surface side of the resin film (A) is wound in a roll shape. It is a film-wrapped layer made of
The release film (C) has a base material layer (C1) and an adhesive layer (C2).
Delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C), and delamination strength F2 (N / 20 mm width) between the release film (C) and the easy-adhesion layer (B). ), Both F1 and F2 are 0.01 or more and 1.0 or less, and F2 is larger than F1. The film winding layer according to claim 1, wherein the delamination strength F1 (N / 20 mm width) between the resin film (A) and the release film (C) is 0.01 or more and 0.1 or less. body. The film-wrapped layer according to claim 1 or 2, wherein the storage elastic modulus G'(MPa) of the easy-adhesion layer (B) at 23 ° C. is 0.1 or more and 100 or less. The film winding layer according to any one of claims 1 to 3, wherein the winding tension is 10 N / m width or more and 200 N / m width or less. The film winding layer according to any one of claims 1 to 4, wherein the resin film (A) is a film having a layer containing an acrylic polymer as a main component resin as the outermost surface layer. body. The resin film (A) is a three-layer film in which a layer containing an alicyclic structure-containing polymer as a main component resin is provided as an intermediate layer, and layers containing an acrylic polymer as a main component resin are provided on both the front and back sides thereof. The film-wrapped layer according to any one of claims 1 to 4, wherein the film-wrapped layer body is characterized by the above. The film-wrapped layer according to any one of claims 1 to 4, wherein the resin film (A) is a single-layer film composed of a layer containing an acrylic polymer as a main component resin. The film-wrapped layer according to any one of claims 1 to 7, wherein the thickness of the resin film (A) is 3 μm or more and 80 μm or less. The film-wrapped layer according to any one of claims 1 to 8 , wherein the thickness of the easy-adhesion layer (B) is 0.5 μm or more and 2.5 μm or less. The film-wrapped layer according to any one of claims 1 to 9, wherein the easy-adhesion layer (B) contains a urethane-based resin as a main component resin. The film winding layer according to any one of claims 1 to 10, wherein the laminated film has a layer structure of an easy-adhesion layer (B) / a resin film (A) / a release film (C). body. A laminated body having a structure in which an adhesive layer is laminated on the outside of an easy-adhesive layer (B) of a laminated film obtained by rewinding the film wound layer according to any one of claims 1 to 11. The laminate according to claim 12, wherein the adhesive layer contains a water-soluble adhesive as a main component. A liquid crystal display device comprising the laminate according to claim 12 or 13.