KR20190049493A - Laminate - Google Patents

Abstract

The present invention relates to a laminate which includes a polarizing plate having a surface protection film laminated on one surface thereof and a delamination film laminated on the other surface thereof. The polarizing plate includes a polarizer. In the surface protection film, the product (K3) of maximum force F3 (N) and deformation S3 (mm) is 1.00 N·mm or greater in a bending state at a time when a barb jig is vertically dropped. Therefore, the laminate can prevent delamination defects of the delamination film. In addition, the product (K1) of the maximum force F1 (N) and deformation S1 (mm) is 3.70 N·mm or greater in a bending state of a layer, formed of the polarizing plate and the surface protection film, at a time when the barb jig is vertically dropped to the layer. However, the product (K2) of maximum force F2 (N) and deformation S2 (mm) may be 1.00 N·mm or less in a bending state of the polarizing plate.

Description

Laminate {LAMINATE}

More particularly, the present invention relates to a laminate comprising a polarizing plate including a polarizer, a surface protective film which is laminated on one surface of the polarizing plate in such a manner that the surface protective film can be peeled off and a peeling film is peelably laminated via the pressure- .

BACKGROUND ART [0002] Polarizing plates are widely used in image display devices such as liquid crystal display devices and organic electroluminescence (EL) display devices, and particularly in recent years, various mobile devices such as smart phones.

As the polarizing plate, conventionally, a polarizing plate is used, specifically, a polarizing plate obtained by bonding a protective film to one side or both sides of a polarizer in which a dichroic dye is adsorbed and aligned on a polyvinyl alcohol resin film is used.

Such a polarizing plate is generally distributed on the market as a laminate obtained by adhering a releasable surface protective film (also referred to as a protect film) and a release film (also referred to as a separator film) on its surface for preventing contamination or scratching of its surface to be.

When a polarizing plate is bonded to a display element such as a liquid crystal cell or an organic EL element, the release film bonded to the surface is peeled off and the polarizing plate is bonded to the display element through the exposed pressure-sensitive adhesive layer. When the peeling film is peeled off, as shown in Patent Document 1 (Japanese Patent Application Laid-Open No. 6-48633), a laminate (a surface protective film is laminated on one side of a polarizing plate and a peeling film is laminated on the other side The surface protective film side of the film is fixed to the supporter by a method such as suction / absorption, and the peeling tape is bonded onto the peeling film. Thereafter, the peeling tape is pulled to remove the peeling film from the polarizing plate surface. In view of the fact that the phenomenon that the polarizing plate is peeled off from the surface protective film can be suppressed at this time, the surface protective film has a relatively low rigidity, specifically, a maximum force F (N ) And the deformation (S (mm)) is preferably 1.00 N · mm or less.

However, in the conventional laminate, when the release film is peeled, the fixed polarizer and the surface protective film float up from the holding chamber following the movement of the release film, and the polarizer and the surface protection film are unfixed , There is a problem that peeling of the peeling film can not be easily performed. In recent years, the thickness of the polarizing plate has become thinner, the polarizing plate has lost its elasticity, the rigidity has become relatively low, and peeling failure is more likely to occur.

This problem can be solved by increasing the force such as the suction force or the suction force when fixing the laminate or decreasing the adhesive force of the release film, but on the other hand, a new problem arises. That is, when the force acting on the laminate such as a force for suction or a force for adsorption increases, the appearance of the polarizer is deteriorated. Further, if the adhesive strength of the release film is reduced, a gap is formed between the release film and the polarizer when an impact is applied to the laminate during transportation or the like.

[Patent Document 1] JP-A-6-48633

An object of the present invention is to provide a laminate in which peeling failure of the peeling film does not occur.

[1] A surface protective film is laminated on one surface of a polarizing plate so as to be peelable,

A peeling film is peelably laminated on the other surface of the polarizing plate via a pressure-sensitive adhesive layer,

Wherein the polarizer includes a polarizer,

The maximum force F3 (N (N)) is obtained when F3 is the maximum force F (N) measured by the following measuring method, and S3 is the strain (S And a stiffness K3 expressed as a product (F3 (N) xS3 (mm)) of a deformation S3 (mm)

When the maximum force F (N) measured by the following measuring method is F1 and the deformation (S (mm)) is S1, the layer comprising the polarizing plate and the surface protective film is used as a measurement film And the rigidity K1 expressed by the product F1 (N) S1 (mm) of the maximum force F1 (N) and the deformation S1 (mm) is 3.70 N · mm or more and 10.0 N · mm or less.

How to measure:

The measurement table has a circular through-hole at its center as viewed from the upper surface, a diameter of the through-hole at the upper surface is 30 mm, and the shape of the through hole viewed from the side is a shape composed of a columnar lower portion and a hemispherical upper portion ,

A rectangular measurement film of 25 mm x 43 mm was placed,

A needle having a spherical tip and a tip diameter of 1 mm phi and a radius of curvature of 0.5 mm was passed from above the measurement film at a rate of 1.0 cm / sec so that the needle passed through the center of the through hole of the measurement bench Vertically descending,

After the tips of the needles contact the measuring film, the maximum load at which the film keeps bent is measured as the maximum force F (N), and the strain S (mm) of the film at that time is measured.

[2] The maximum force F2 (N) is obtained when the maximum force F (N) measured by the above measuring method is F2 (N) and the strain S (mm) (1), wherein a rigidity K2, which is expressed by a product of a thickness (N) and a deformation S2 (mm), is not more than 1.00 N · mm.

[3] A laminate according to [1] or [2], wherein the adhesion between the polarizing plate and the release film is 0.02 to 0.05 N / 25 mm.

[4] a step of fixing the surface protective film in the laminate described in any one of [1] to [3] to a holding table with an adhesion force of 0.1 to 0.3 N / 60 mm;

A step of peeling off the release film from the laminate

Wherein the polarizing plate is a polarizing plate.

According to the present invention, it is possible to provide a laminate in which peeling failure of the peeling film does not occur.

1 is a schematic cross-sectional view showing an example of the layer configuration of the laminate of the present invention.
2 is a schematic cross-sectional view showing an example of the layer configuration of the laminate of the present invention.
Fig. 3 is a schematic view showing a device for measuring the maximum force F and strain S in a state in which the film is warped.
4 is a view for explaining the maximum force F and the strain S in a state in which the film is bent.
Fig. 5 is an image showing an example of a state in which the film is folded in. Fig.

<Laminate>

The laminate has a surface protective film laminated on one surface of a polarizing plate and a release film laminated on the other surface of the polarizing plate. The polarizing plate has at least a polarizer. Hereinafter, with reference to the drawings, an example of the layer structure of the laminate of the present invention will be described. The polarizing plate may be provided with a protective film, a retardation layer, a brightness enhancement film and the like in addition to the polarizer. The polarizing plate may have a pressure-sensitive adhesive layer for adhering the polarizer, the retardation layer, the brightness enhancement film, and the like to each other.

1 is a schematic cross-sectional view showing an example of the laminate of the present invention. The laminate 100 shown in Fig. 1 (a) comprises a surface protective film 30 laminated on one surface of a polarizing plate 10 and a peeling film 20 laminated on the other surface of the polarizing plate 10 . The surface protective film 30 is composed of a base film 31 and a pressure-sensitive adhesive layer 32 laminated thereon. The surface protective film 30 is peelable from the polarizing plate 10 in a state in which the base film 31 and the pressure-sensitive adhesive layer 32 are laminated. In the polarizing plate 10, the protective film 12 is laminated on one side of the polarizer 11 through an adhesive layer (not shown), and the brightness enhancement film 14 is laminated on the other side through the adhesive layer 16 , And a pressure-sensitive adhesive layer (15) are laminated on the protective film (12). The surface protection film 30 is laminated on the brightness enhancement film 14. On the pressure-sensitive adhesive layer 15, a release film 20 is laminated. The peeling film 20 is peelable from the polarizing plate 10 while leaving the pressure-sensitive adhesive layer 15.

The laminate 101 shown in Fig. 1 (b) comprises a surface protective film 30 laminated on one side of the polarizing plate 10 and a peeling film 20 laminated on the other side of the polarizing plate 10 . The surface protection film 30 is composed of a base film 31 and a pressure-sensitive adhesive layer 32 laminated thereon. The surface protective film 30 is peelable from the polarizing plate 10 in a state in which the base film 31 and the pressure-sensitive adhesive layer 32 are laminated. In the polarizing plate 10, the protective film 12 is laminated on one side of the polarizer 11 through an adhesive layer (not shown), and the protective film 13 is laminated on the other side through an adhesive layer (not shown) A layer structure in which a pressure sensitive adhesive layer 15 is laminated on a protective film 12 and a brightness enhancement film 14 is laminated on the protective film 13 through a pressure sensitive adhesive layer 16. The surface protection film 30 is laminated on the brightness enhancement film 14. On the pressure-sensitive adhesive layer 15, a release film 20 is laminated. The peeling film 20 can be peeled from the polarizing plate 10 while leaving the pressure-sensitive adhesive layer 15.

The laminate 102 shown in Fig. 2A is composed of a surface protective film 30 laminated on one surface of a polarizing plate 10 and a peeling film 20 laminated on the other surface of the polarizing plate 10 . The surface protection film 30 is composed of a base film 31 and a pressure-sensitive adhesive layer 32 laminated thereon. The surface protective film 30 is peelable from the polarizing plate 10 in a state in which the base film 31 and the pressure-sensitive adhesive layer 32 are laminated. In the polarizing plate 10, the protective film 12 is laminated on one side of the polarizer 11 through an adhesive layer (not shown), and the protective film 13 is laminated on the other side through an adhesive layer (not shown) A layer structure in which the retardation layer 17 is laminated on the protective film 12 through an adhesive layer or a pressure sensitive adhesive layer not shown and the pressure sensitive adhesive layer 15 is laminated on the retardation layer 17 is shown. On the pressure-sensitive adhesive layer 15, a release film 20 is laminated. This release film can be peeled off from the polarizing plate 10 while leaving the pressure-sensitive adhesive layer 15.

The laminate 103 shown in Fig. 2 (b) has a surface protective film 30 laminated on one side of the polarizing plate 10 and a peeling film 20 laminated on the other side of the polarizing plate 10 . The surface protection film 30 is composed of a base film 31 and a pressure-sensitive adhesive layer 32 laminated thereon. The surface protective film 30 is peelable from the polarizing plate 10 in a state in which the base film 31 and the pressure-sensitive adhesive layer 32 are laminated. The polarizing plate 10 is constituted such that the retardation layer 17 is laminated on one side of the polarizer 11 through an adhesive layer or an adhesive layer not shown and the protective film 13 is laminated on the other side through an adhesive layer And a pressure-sensitive adhesive layer (15) is laminated on the retardation layer (17). On the pressure-sensitive adhesive layer 15, a release film 20 is laminated. The peeling film 20 is peelable from the polarizing plate 10 while leaving the pressure-sensitive adhesive layer 15.

In the layered products 100 to 103, it is preferable that the surface protective film 30 and the release film 20 are members constituting the outermost surface of the laminate. The layers 100 to 103, the polarizing plate 10, the release film 20, and the surface protection film 30 may have layers other than the illustrated layers.

In the layered product of the present embodiment, the layer comprising the polarizing plate and the surface protective film has a maximum force F1 (N) and a deformation S1 (mm) measured by the above measuring method, that is, When the jig is vertically lowered, the product of the maximum force F1 (N) in the warped state and the deformation S1 (mm) is 3.70 N · mm or more. The product K1 of the maximum force F1 (N) and the deformation S1 (mm) in the bent state is preferably 4.5 N · mm or more, more preferably 5.0 N · mm or more, and usually 10.0 N · mm Or less and 9.0 N · mm or less. In order to set the range of the product (K1) of the force F1 (N) to the deformation S1 (mm), it is preferable to select and combine, for example, a surface protective film and a polarizing plate. When a surface protective film having a relatively large product K3 of a maximum force F3 (N) and a deformation S3 (mm), that is, a surface protective film having high rigidity is used as the surface protective film, the F1 (N) and S1 ) Becomes larger. Examples of such a surface protective film include a surface protective film having a large thickness, a surface protective film made of a hard material resin, and the like. Further, even if a high rigidity material is used as the polarizing plate, the product K1 of F1 (N) and S1 (mm) becomes large.

F1 (N) may be 1.0 N or more and 3.0 N or less, 1.5 N or more and 3.0 N or less. S1 (mm) may be 1.5 mm or more and 5.0 mm or less, and may be 2.0 mm or more and 4.0 mm or less.

The product of the maximum force F1 (N) in the warped state and the deformation S1 (mm) can be measured using, for example, KES-G5, a compression tester manufactured by Kato Tech Co., Ltd. 3, Fig. 4 and Fig. 5. Fig.

Here, a method of measuring the maximum force F (N) and the strain S (mm) in the warped state of the film (measurement film) to be measured will be described. When the measuring film is a layer comprising a polarizing plate and a surface protecting film, F1 and S1 are measured. When the measuring film is a polarizing plate, F2 and S2 are measured. When the measuring film is a surface protecting film, F3 and S3 are measured.

First, the measuring film 3 to be measured is placed on the measuring stand 2. The measurement film 3 is a layer comprising a polarizing plate and a surface protective film, a polarizing plate alone, or a surface protective film alone. A fixing jig may not be provided on the film 3 to be measured. The base 2 has a circular gap (through hole) at the center as viewed from the upper surface, and the diameter of the gap on the upper surface (both arrows 44) is 30 mm. The shape of the pore seen from the side surface may be a shape such as a shape formed by a columnar lower portion and a hemispherical upper portion (a bell-shaped), a pyramid-shaped (cone-shaped, conical) (Tapered shape). The size of the measuring film 3 to be measured is a rectangle of 25 mm (both arrows 43) 43 mm (both arrows 42).

Next, the protruding jig 1 is lowered vertically from above the loaded film 3. At this time, let the protruding jig 1 pass through the center of the circular gap. The protruding jig 1 is a needle having a spherical tip, a tip diameter of 1 mm phi, and a curvature of 0.5 R (radius of curvature of 0.5 mm). The speed at which the protruding jig 1 is lowered is 1.0 cm / sec.

The maximum load N and strain (mm) at which the film 3 is kept bent after the tip of the protruding jig (needle) 1 comes into contact with the measuring film 3 are measured. That is, if the protruding jig 1 is lowered to the measuring film 3, wrinkles or folds are generated in the measuring film 3 (for example, folding shown in Fig. 4 (b) and Fig. 5) In the present embodiment, the load immediately before it and the deformation (the length of the both arrows 40) are measured. The state in which the measuring film 3 is warped refers to a state in which the film 3 is curved (for example, an arcuate shape such as an arc shape, an elliptic arc shape, a catenary shape, or the like) when viewed from the side 4 (a)).

(K2) of the maximum force F2 (N) in the bent state and the deformation S2 (mm) when the protruding jig is vertically lowered with respect to the single polarizer in the laminated body of this embodiment, May be 1.00 N · mm or less, or 0.70 N · mm or less. In this case, with respect to the surface protective film, if the product (K3) of the maximum force F3 (N) in the warped state and the deformation S3 (mm) when the protruding jig is lowered vertically is 0.50 N · mm or more , Peeling failure of the peeling film hardly occurs, which is preferable. When the product of the maximum force F2 (N) and the deformation S2 (mm) is 0.30 N · mm or less, the product of the maximum force F3 (N) and the deformation S3 (mm) is preferably 0.30 N · mm or more. When the product of the maximum force F2 (N) and the deformation S2 (mm) is 0.20 N · mm or less, the product of the maximum force F3 (N) and the deformation S3 (mm) is preferably 0.50 N · mm or more. Even when a polarizing plate having low rigidity is used, the peeling failure of the release film can be reduced by selecting the surface protection film having high rigidity. By using such a combination, even when the laminate has a polarizer with low rigidity, peeling failure of the release film is less likely to occur.

The laminate may be obtained by preparing a laminate of an elongated shape by a roll-to-roll method while conveying each member constituting the laminate, preparing each member of a predetermined shape, May be obtained by sequentially laminating them.

The shape of the laminate is not particularly limited, but may be a polygon such as a rectangle or a triangle, a circle, an ellipse, or a combination thereof.

When the laminate has a rectangular shape with long sides and short sides, the length of the long side is preferably 35 to 5 cm, more preferably 25 to 10 cm, and the length of the short side is preferably 25 to 5 cm, More preferably 20 to 6 cm. By setting the size to such a range, more peelability can be improved.

Hereinafter, the respective members of the laminate will be described.

<Polarizer>

The polarizing plate has a polarizing plate in which the product K2 of the maximum force F2 (N) in the warped state and the deformation S2 (mm) when the protruding jig is vertically lowered is usually 0.10 N · mm or more, More preferably 0.15 N · mm or more, more preferably 0.20 N · mm or more, and still more preferably 0.30 N · mm or more. The product K2 of the maximum force F2 (N) and the deformation S2 (mm) may be 1.00 N · mm or less and 0.70 N · mm or less. Even if the product K2 is 1.00 N · mm or less, the release film can be peeled off without causing detachment failure if the laminate of the present invention is used. The product K2 of the maximum force F2 (N) and the strain S2 (mm) can be obtained in the same manner as the method of obtaining the product of the maximum force F1 (N) and the deformation S1 (mm).

F2 (N) may be 0.20 N or more and 1.0 N or less, and may be 0.3 N or more and 0.8 N or less. S2 (mm) may be 0.5 mm or more and 3.0 mm or less, and may be 1.0 mm or more and 2.0 mm or less.

(K2) of the maximum force F2 (N) and the deformation S2 (mm) when at least one of the case where the polarizing plate is provided with the protective film only on one side of the polarizer and the case where the polarizing plate is provided with the luminance improving film , Tends to be smaller. Further, the stretching magnification and the stretching temperature of the polarizer can also influence the magnitude of the product of the maximum force F2 (N) and the strain S2 (mm). For example, when the stretching magnification of the polarizer is increased, the product K2 of the maximum force F2 (N) and the deformation S2 (mm) tends to become small, and when the stretching magnification of the polarizer is made small, the product K2 becomes large There is a tendency.

The polarizing plate 10 is a polarizing element including at least a polarizer, and usually further includes a thermoplastic resin film bonded to one surface or both surfaces thereof. The thermoplastic resin film may be a protective film for protecting the polarizer, another film having an optical function, or the like. Although the thermoplastic resin film is provided with a resin layer (at least one kind of optical layer selected from a hard coat layer, an antistatic layer, an antiglare layer, a light diffusion layer, an antireflection layer, a low refractive index layer, good. The thermoplastic resin film can be bonded to the polarizer through the adhesive layer. The surface protection film 30 may be laminated on the surface of the resin layer.

In the case where the laminate further includes a brightness enhancement film or a retardation layer, the effect of the present invention is remarkable. A polarizing plate including a brightness enhancement film or the like is low in stiffness and prone to peeling failure. According to the present invention, even when the laminate includes a brightness enhancement film or the like, the occurrence of peeling failure can be reduced.

The effect of the present invention is remarkable when the thickness (占 퐉) of the polarizing plate is usually not more than 150 占 퐉, the rigidity is not more than 75 占 퐉, and further, not more than 70 占 퐉. The thickness of the polarizing plate 10 is preferably 30 占 퐉 or more, and more preferably 50 占 퐉 or more.

(1) Polarizer

The polarizer constituting the polarizing plate 10 is an absorption type liquid crystal display device having a property of absorbing linearly polarized light having a vibration surface parallel to the absorption axis thereof and transmitting linearly polarized light having a vibration surface (parallel to the transmission axis) And a polarizer in which a dichroic dye is adsorbed and aligned on a uniaxially stretched polyvinyl alcohol-based resin film can be suitably used. The polarizer may be, for example, a process of uniaxially stretching a polyvinyl alcohol-based resin film; A step of adsorbing a dichroic dye by staining a polyvinyl alcohol-based resin film with a dichroic dye; A step of treating a polyvinyl alcohol-based resin film adsorbed with a dichroic dye with a crosslinking solution such as an aqueous solution of boric acid; And a step of washing with water after the treatment with the crosslinking liquid.

As the polyvinyl alcohol-based resin, a saponified polyvinyl acetate-based resin can be used. As the polyvinyl acetate resin, a copolymer of vinyl acetate, which is a homopolymer of vinyl acetate, and other monomers copolymerizable with vinyl acetate, and the like can be given. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth) acrylamides having an ammonium group.

In the present specification, "(meth) acryl" means at least one selected from acrylic and methacrylic. (Meth) acryloyl &quot;, &quot; (meth) acrylate &quot;, and the like.

The saponification degree of the polyvinyl alcohol-based resin is usually 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The average degree of polymerization of the polyvinyl alcohol-based resin is usually 1,000 to 10,000, preferably 1,500 to 5,000. The average polymerization degree of the polyvinyl alcohol-based resin can be obtained according to JIS K 6726.

Such a polyvinyl alcohol-based resin is used as a raw film of a polarizer (polarizer). The method of forming the polyvinyl alcohol-based resin is not particularly limited, and a known method is employed. The thickness of the polyvinyl alcohol-based original film is not particularly limited, but it is preferable to use a film having a thickness of 5 to 35 μm in order to make the thickness of the polarizer 15 μm or less. More preferably, it is 20 mu m or less.

The uniaxial stretching of the polyvinyl alcohol based resin film can be performed before, simultaneously with, or after dyeing the dichroic dye. When uniaxial stretching is performed after dyeing, the uniaxial stretching may be performed before or during the crosslinking treatment. In addition, uniaxial stretching may be performed in these plural steps.

During uniaxial stretching, stretching may be uniaxially stretched between rolls having different peripheral velocities, or uniaxial stretching may be performed using hot roll. The uniaxial stretching may be dry stretching in which stretching is performed in the atmosphere, or wet stretching in which stretching is performed in a state in which the polyvinyl alcohol based resin film is swollen with a solvent or water. The draw ratio is usually 3 to 8 times.

As a method for dyeing a polyvinyl alcohol-based resin film with a dichroic dye, for example, a method of immersing the film in an aqueous solution containing a dichroic dye is employed. As the dichroic dye, iodine or a dichroic organic dye is used. On the other hand, it is preferable that the polyvinyl alcohol-based resin film is subjected to immersion treatment in water before the dyeing treatment.

As a crosslinking treatment after dyeing with a dichroic dye, a method of immersing a dyed polyvinyl alcohol resin film in an aqueous solution containing boric acid is usually employed. When iodine is used as the dichroic dye, it is preferable that the aqueous solution containing boric acid contains potassium iodide.

The thickness of the polarizer is usually 30 μm or less, preferably 20 μm or less, more preferably 15 μm or less, and further preferably 10 μm or less. Particularly, it is advantageous to make the thickness of the polarizer 15 mu m or less to make the laminate thinner. The thickness of the polarizer is usually 2 占 퐉 or more, and preferably 3 占 퐉 or more from the viewpoint of imparting elasticity to the polarizing plate.

As the polarizer, for example, a cured film obtained by polymerizing a liquid crystal compound and having a dichroic dye oriented may be used as described in JP-A-2016-170368. As the dichroic dye, those having absorption within a wavelength range of 380 to 800 nm can be used, and it is preferable to use an organic dye. As the dichroic dye, for example, an azo compound can be mentioned. The liquid crystal compound is a liquid crystal compound that can be polymerized while being oriented, and may have a polymerizable group in the molecule.

(2) Protective film

The protective film that can be laminated on one side or both sides of the polarizer is preferably a thermoplastic resin having translucency (preferably optically transparent) such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin (norbornene- Resin and the like); Cellulose-based resins such as triacetylcellulose and diacetylcellulose; Polyester-based resins such as polyethylene terephthalate and polybutylene terephthalate; Polycarbonate resin; (Meth) acrylic resins such as methyl methacrylate resins; Polystyrene type resin; Polyvinyl chloride resins; Acrylonitrile-butadiene-styrene-based resin; Acrylonitrile-styrene series resin; Polyvinyl acetate resin; Polyvinylidene chloride resins; Polyamide based resin; A polyacetal-based resin; Modified polyphenylene ether-based resin; Polysulfone resins; Polyether sulfone type resin; Polyarylate resins; Polyamideimide series resin; A polyimide-based resin, or the like.

Examples of the chain polyolefin-based resin include polyethylene resin (a polyethylene resin which is a homopolymer of ethylene or a copolymer mainly composed of ethylene), a polypropylene resin (a polypropylene resin which is a homopolymer of propylene or a copolymer mainly composed of propylene) A homopolymer of the same chain olefin, and a copolymer of two or more chain olefins.

The cyclic polyolefin-based resin is a general term for resins polymerized by using cyclic olefins as polymerized units, and examples thereof include those described in JP-A-1-240517, JP-A-3-14882, -122137, and the like. Specific examples of the cyclic polyolefin resin include a ring-opened (co) polymer of cyclic olefin, an addition polymer of cyclic olefin, a copolymer (typically a random copolymer) of cyclic olefin and a chain olefin such as ethylene and propylene, And graft polymers obtained by modifying these with an unsaturated carboxylic acid or a derivative thereof, and hydrides thereof. Among them, a norbornene-based resin using a norbornene-based monomer such as norbornene or a polycyclic norbornene-based monomer as a cyclic olefin is preferably used.

The polyester-based resin is a resin having an ester bond except for the following cellulose ester-based resin, and is generally composed of a polycondensation product of a polyvalent carboxylic acid or a derivative thereof and a polyhydric alcohol. As the polycarboxylic acid or its derivative, a bivalent dicarboxylic acid or a derivative thereof can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethylterephthalate and dimethyl naphthalenedicarboxylate. As the polyhydric alcohol, a divalent diol can be used, and examples thereof include ethylene glycol, propanediol, butanediol, neopentyl glycol and cyclohexanedimethanol. As a representative example of the polyester-based resin, polyethylene terephthalate which is a polycondensation product of terephthalic acid and ethylene glycol can be mentioned.

The (meth) acrylic resin is a resin mainly composed of a compound having a (meth) acryloyl group. Specific examples of the (meth) acrylic resin include poly (meth) acrylic acid esters such as polymethyl methacrylate; Methyl methacrylate- (meth) acrylic acid copolymer; Methyl methacrylate- (meth) acrylic acid ester copolymer; Methyl methacrylate-acrylic acid ester- (meth) acrylic acid copolymer; (Meth) acrylate-styrene copolymer (MS resin and the like); A copolymer of a compound having an alicyclic hydrocarbon group and a methyl methacrylate (e.g., a methyl methacrylate-cyclohexyl copolymer, a methacrylic acid methyl- (meth) acrylate norbornyl copolymer, etc.). Preferably, a polymer mainly composed of a poly (meth) acrylate C _1-6 alkyl ester such as poly (meth) acrylate is used, more preferably methyl methacrylate as a main component (50 to 100 wt% By weight, preferably 70 to 100% by weight) is used.

The cellulose ester resin is an ester of cellulose and a fatty acid. Specific examples of the cellulose ester-based resin include cellulose triacetate, cellulose diacetate, cellulose tripropionate, and cellulose dipropionate. Further, copolymers thereof and those obtained by modifying a part of hydroxyl groups with other substituents are also cited. Of these, cellulose triacetate (triacetylcellulose) is particularly preferable.

The polycarbonate resin is an engineering plastic composed of a polymer having a monomer unit bonded through a carbonate group.

It is also useful to control the retardation value of the protective film to a value suitable for an image display device such as a liquid crystal display device. For example, in a liquid crystal display device of an in-plane switching (IPS) mode, it is preferable to use a film whose retardation value is substantially zero as the protective film. Substantially zero phase retardation value means that the in-plane retardation value R ₀ at a wavelength of 590 nm is 10 nm or less, the absolute value of the thickness direction retardation value R _{th at} a wavelength of 590 nm is 10 nm or less, and the wavelengths 480 to 750 Nm means that the absolute value of the thickness direction retardation value R _th is 15 nm or less.

For example, depending on the mode of the liquid crystal display device, the protective film may be subjected to stretching and / or shrinking processing to give a suitable retardation value. For example, a single-layer or multi-layered retardation layer (or film) can be used as a protective film for the purpose of viewing angle compensation. In this case, the polarizing plate 10 may be an elliptically polarizing plate or circular polarizing plate including a lamination structure of a polarizer and a retardation layer, or a polarizing plate having a viewing angle compensating function including a retardation layer.

The thickness of the protective film is usually 1 to 100 占 퐉, but is preferably 5 to 60 占 퐉, more preferably 10 to 55 占 퐉, and further preferably 15 to 40 占 퐉 in view of strength and handleability. When a protective film constituting the polarizing plate having a thickness within this range is used, a product (K2) of F2 (N) and S2 (mm) of the polarizing plate itself including the protective film, It is easy to adjust the product (K1) of F1 (N) of the film and S1 (mm). Specifically, when a thick protective film having a thickness within the above range is used as the protective film, the product (K2) or the product (K1) tends to become large. If the thickness is made thinner within the above range, (K1) tends to become smaller. Also, if the thickness of the protective film is within this range, the polarizer is mechanically protected, so that even when exposed under a humid (hot) environment, the polarizer does not shrink, and stable optical characteristics can be maintained.

It is also possible to adjust the product K1 of F1 (N) and S1 (mm), or the product K2 of F2 (N) and S2 (mm) by selecting a material exhibiting high rigidity as a material constituting the protective film It is possible. When a material having high rigidity is used as the material constituting the protective film, the product K1 of F1 (N) and S1 (mm) or the product K2 of F2 (N) and S2 (mm) tends to increase . When a material having a low rigidity is used as the material constituting the protective film, the product K1 of F1 (N) and S1 (mm) or the product K2 of F2 (N) and S2 (mm) have.

In the case where the protective film is bonded to both surfaces of the polarizer, these protective films may be composed of the same kind of thermoplastic resin or may be composed of different kinds of thermoplastic resins. The thickness may be the same or different. Further, they may have the same retardation characteristics or different retardation characteristics.

As described above, at least one of the protective films has a surface such as a hard coat layer, an antiglare layer, a light diffusion layer, an antireflection layer, a low refractive index layer, an antistatic layer and a contamination preventing layer on its outer surface (surface opposite to the polarizer) And a treatment layer (coating layer) may be provided. On the other hand, the thickness of the protective film includes the thickness of the surface treatment layer.

It is preferable that the surface of the polarizing plate 10 on the surface protective film 30 side (the surface to which the surface protective film 30 is bonded) and the surface treatment layer It is preferable that the arithmetic mean roughness Ra in accordance with JIS B 0601: 2013 is small. Specifically, the Ra of the surface is preferably 0.3 m or less, more preferably 0.2 m or less, and further preferably 0.15 m or less. Ra of the surface is usually 0.001 m or more, for example, 0.005 m or more.

The protective film can be bonded to the polarizer through, for example, an adhesive layer. As the adhesive forming the adhesive layer, an aqueous adhesive, an active energy ray curable adhesive, or a thermosetting adhesive can be used, and preferably an aqueous adhesive and an active energy ray curable adhesive.

Examples of the water-based adhesive include an adhesive composed of a polyvinyl alcohol-based resin aqueous solution, an aqueous two-component emulsion type urethane emulsion adhesive, and the like. Among them, an aqueous adhesive composed of a polyvinyl alcohol-based resin aqueous solution is suitably used. Examples of the polyvinyl alcohol-based resin include a polyvinyl alcohol-based copolymer obtained by saponifying a copolymer of vinyl acetate and another monomer copolymerizable therewith, in addition to a vinyl alcohol homopolymer obtained by saponifying a polyvinyl acetate which is a homopolymer of vinyl acetate Or a modified polyvinyl alcohol-based polymer obtained by partially modifying the hydroxyl group thereof, and the like can be used. The water-based adhesive may include a crosslinking agent such as an aldehyde compound (glyoxal, etc.), an epoxy compound, a melamine compound, a methylol compound, an isocyanate compound, an amine compound or a polyvalent metal salt.

When an aqueous adhesive is used, it is preferable to carry out a drying step for removing water contained in the aqueous adhesive after bonding the polarizer and the protective film. After the drying step, a curing step may be provided for curing at a temperature of 20 to 45 占 폚, for example.

The active energy ray curable adhesive is an adhesive containing a curable compound which is cured by irradiation with active energy rays such as ultraviolet rays, visible rays, electron beams and X rays, and is preferably an ultraviolet ray curable adhesive.

The curable compound may be a cationically polymerizable curable compound or a radically polymerizable curable compound. Examples of the cationically polymerizable curable compound include epoxy compounds (compounds having one or two or more epoxy groups in the molecule), oxetane compounds (compounds having one or two or more oxetane rings in the molecule) Combinations. Examples of the radically polymerizable curable compound include (meth) acrylic compounds (compounds having one or more (meth) acryloyloxy groups in the molecule), other vinyl compounds having a radically polymerizable double bond, or And combinations thereof. The cationic polymerizable curable compound and the radical polymerizable curable compound may be used in combination. The active energy ray curable adhesive usually further comprises a cation polymerization initiator and / or a radical polymerization initiator for initiating the curing reaction of the curable compound.

At the time of bonding the polarizer and the protective film, the surface of at least one of them may be subjected to a surface activation treatment in order to improve the adhesiveness. Examples of the surface activation treatment include dry treatment such as corona treatment, plasma treatment, discharge treatment (glow discharge treatment and the like), flame treatment, ozone treatment, UV ozone treatment, ionization active ray treatment (ultraviolet radiation treatment, electron beam treatment and the like); Wet treatment such as ultrasonic treatment using a solvent such as water or acetone, saponification treatment, and anchor coat treatment. These surface activation treatments may be performed alone or in combination of two or more.

In the case where the protective film is bonded to both surfaces of the polarizer, the adhesive for bonding these protective films may be the same kind of adhesive or different kind of adhesive.

(3) Other films

The polarizing plate 10 may include films other than the polarizer and the protective film, and typical examples thereof include a brightness enhancement film and a retardation layer. In the case where the polarizing plate 10 includes another film, the surface protective film 30 may be laminated on the surface of the film or on the surface of the surface treatment layer laminated on the film.

The brightness enhancement film is also called a reflection type polarizer, and a polarization conversion element having a function of separating outgoing light from a light source (backlight) into transmission polarized light and reflected polarized light or scattered polarized light is used. By arranging the brightness enhancement film on the polarizer, it is possible to improve the emission efficiency of the linearly polarized light emitted from the polarizer by using the recursive light that is the reflected polarized light or the scattered polarized light. The brightness enhancement film can be laminated on the polarizer through the pressure-sensitive adhesive layer. Another film such as a protective film may be interposed between the polarizer and the brightness enhancement film.

The brightness enhancement film may be, for example, an anisotropic reflective polarizer. An example of the anisotropic reflective polarizer is an anisotropic multilayer film that transmits linearly polarized light in one vibration direction and reflects linearly polarized light in the other vibration direction, and a specific example thereof is &quot; APF &quot; Another example of the anisotropic reflective polarizer is a composite of a cholesteric liquid crystal layer and a? / 4 plate, and a specific example thereof is "PCF" manufactured by Nitto Denka Kabushiki Kaisha. Another example of the anisotropic reflective polarizer is a reflective grid polarizer. Specific examples of the anisotropic reflective polarizer include a metal lattice reflective polarizer and metal fine particles, which are produced by subjecting a metal to fine processing to emit a reflected polarized light in a visible light region, Film.

As described above, a hard coat layer, an antiglare layer, a light diffusion layer, a retardation layer (retardation layer having a retardation value of 1/4 wavelength, etc.), an antireflection layer, a low refractive index layer, A surface treatment layer (coating layer) such as an anti-blocking layer may be formed. By forming such a layer, the adhesion to the backlight tape and the uniformity of the display image can be improved. The thickness of the brightness enhancement film 14 is usually 10 to 100 占 퐉, preferably 10 to 50 占 퐉, and more preferably 10 to 30 占 퐉.

Examples of the retardation layer include a quarter wavelength (? / 4) plate, a half wavelength (? / 2) plate, and a positive C plate. The? / 4 plate is a layer whose in-plane retardation value Re (550) at a wavelength of 550 [nm] satisfies the relationship of 100 nm? Re (550)? 200 nm. The? / 4 plate may exhibit an inverse wavelength dispersion satisfying Re (450) < Re (550) < Re (650) The? / 2 plate is a layer in which Re (550) satisfies 210 nm? Re (550)? 300 nm. The positive C plate satisfies the relationship of Nz> Nx? Ny and the retardation value Rth (?) In the thickness direction at the wavelength? [Nm] satisfies the relationship of -300 nm? Rth (550)? -20 nm Is satisfied.

The retardation layer can be formed of, for example, a resin exemplified as the material of the protective film, and among these, a cyclic olefin resin and a styrene resin are preferable. The retardation layer may be formed as a single layer or a plurality of layers. Examples of the retardation layer having a plurality of layers include a resin film (base film) exemplified as a material of the protective film and a layer in which a liquid crystal compound obtained by polymerization of a liquid crystal compound is cured, Or a layer in which a liquid crystal compound is cured. The layer having the retardation may be a layer in which a resin film and / or a liquid crystal compound is cured. The resin film may also serve as the protective film.

The retardation layer may be composed of one kind of retardation layer or plural kinds of retardation layers. When the retardation layer is composed of a plurality of retardation layers, a combination of a 1/4 wave plate and a 1/2 wave plate or a combination of a 1/4 wave plate and a positive C plate is preferable.

It is preferable that the retardation layer includes a layer in which the liquid crystal compound is cured. When the retardation layer is composed of a plurality of layers, either of the retardation layers may include a layer in which the liquid crystal compound is cured. The type of the liquid crystal compound is not particularly limited, but from the shape thereof, it is classified into a rod-like type (rod-shaped liquid crystal compound) and a disc-shaped type (circular liquid crystal compound or discotic liquid crystal compound) . Also, there are low molecular type and high molecular type, respectively. On the other hand, the polymer generally means that the degree of polymerization is 100 or more (Polymer Physics / Phase Transition Dynamics, by Doi Masao, 2 pages, Iwanami Shoten, 1992). In the present embodiment, any of the liquid crystal compounds may be used. It is also possible to use two or more kinds of rod-shaped liquid crystal compounds, two or more kinds of circular liquid crystalline compounds, or a mixture of rod-shaped liquid crystal compounds and circular liquid crystalline compounds.

On the other hand, as the rod-like liquid crystal compound, for example, those described in paragraphs 1 to 3 of JP-A No. 11-513019 or paragraphs [0026] to [0098] of JP-A No. 2005-289980 have. Examples of the discotic liquid crystal compound include those described in paragraphs [0020] to [0067] of JP-A No. 2007-108732 or paragraphs [0013] to [0108] of JP-A No. 2010-244038 And can be suitably used.

More preferably, the retardation layer is formed using a liquid crystal compound having a polymerizable group (a rod-like liquid crystal compound or a discotic liquid crystal compound). This makes it possible to reduce the temperature change of the optical characteristics and the humidity change.

The liquid crystal compound may be a mixture of two or more kinds. In this case, it is preferable that at least one polymerizable group has two or more polymerizable groups. That is, the retardation layer is preferably a layer formed by fixing a rod-like liquid crystal compound having a polymerizable group or a discotic liquid crystal compound having a polymerizable group by polymerization. In this case, it is no longer necessary to exhibit liquid crystallinity after being a layer.

The type of the polymerizable group contained in the rod-like liquid crystal compound or the discotic liquid crystal compound is not particularly limited, and for example, a functional group capable of addition polymerization reaction such as a polymerizable ethylenic unsaturated group or a ring-polymerizable group is preferable. More specifically, examples thereof include (meth) acryloyl group, vinyl group, styryl group, allyl group and the like. Among them, a (meth) acryloyl group is preferable. On the other hand, the (meth) acryloyl group is a concept including both a methacryloyl group and an acryloyl group.

The method of forming the retardation layer is not particularly limited, and a known method can be used. For example, a composition for forming an optically anisotropic layer (hereinafter simply referred to as "composition") containing a liquid crystal compound having a polymerizable group is applied to a predetermined substrate (including a temporary substrate) to form a coating film , And the resulting coating film is subjected to a curing treatment (irradiation with ultraviolet light (light irradiation treatment) or heat treatment) to produce a retardation layer. The prepared retardation layer can be transferred, for example, onto a polarizer or a protective film.

 The application of the composition can be carried out by known methods such as a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method.

 The composition may contain components other than the above-mentioned liquid crystal compound. For example, the composition may contain a polymerization initiator. As the polymerization initiator to be used, for example, a thermal polymerization initiator or a photopolymerization initiator is selected depending on the type of polymerization reaction. Examples of the photopolymerization initiator include a combination of an? -Carbonyl compound, an acyloin ether, an? -Hydrocarbon-substituted aromatic acyloin compound, a polynuclear quinone compound, a triarylimidazole dimer and p-aminophenyl ketone . The amount of the polymerization initiator to be used is preferably 0.01 to 20 mass%, more preferably 0.5 to 5 mass%, based on the total solid content of the composition.

The composition may also contain a polymerizable monomer in view of the uniformity of the coating film and the strength of the film. Examples of the polymerizable monomer include a radical polymerizable or cationic polymerizable compound. Among them, a multifunctional radically polymerizable monomer is preferable.

On the other hand, as the polymerizable monomer, it is preferable to copolymerize with the above-mentioned liquid crystalline compound containing a polymerizable group. Specific examples of the polymerizable monomer include those described in paragraphs [0018] to [0020] of Japanese Patent Application Laid-Open No. 2002-296423. The amount of the polymerizable monomer to be used is preferably 1 to 50% by mass, and more preferably 2 to 30% by mass with respect to the total mass of the liquid crystal compound.

Further, the composition may contain a surfactant in view of the uniformity of the coating film and the strength of the film. As the surfactant, conventionally known compounds may be mentioned. Of these, a fluorine-based compound is particularly preferable.

In addition, the composition may contain a solvent, and an organic solvent is preferably used. Examples of the organic solvent include amides such as N, N-dimethylformamide, sulfoxides such as dimethylsulfoxide, heterocyclic compounds such as pyridine, hydrocarbons such as benzene and hexane, For example, chloroform, dichloromethane), esters (for example, methyl acetate, ethyl acetate, butyl acetate), ketones (e.g., acetone, methyl ethyl ketone), ethers (e.g., tetrahydrofuran, 1,2-dimethoxyethane) . Among them, alkyl halides and ketones are preferable. Two or more kinds of organic solvents may be used in combination.

The composition also includes various orienting agents such as a vertical alignment promoter such as a polarizer-side vertical alignment agent, an air interface side vertical alignment agent, and a horizontal alignment promoter such as a polarizer interface side horizontal alignment agent and an air interface side horizontal alignment agent There may be. In addition to the above components, the composition may also contain an adhesion improver, a plasticizer, a polymer, and the like.

The retardation layer may contain an alignment film having a function of defining the alignment direction of the liquid crystal compound. The alignment film generally comprises a polymer as a main component. As polymer materials for alignment films, there are descriptions in many documents, and a large number of commercially available products are available. Among them, polyvinyl alcohol or polyimide or a derivative thereof is preferably used as the polymer material, and it is particularly preferable to use modified or unmodified polyvinyl alcohol.

On the other hand, the orientation film is subjected to a generally known orientation treatment. For example, a rubbing treatment and a photo-alignment treatment with polarization can be mentioned, but from the viewpoint of the surface roughness of the alignment film, photo-alignment treatment is preferable.

The thickness of the layer in which the liquid crystal compound is cured is not particularly limited, but is preferably 0.5 to 10 mu m, more preferably 1.0 to 5 mu m. The thickness of the alignment film is not particularly limited, but is often 20 占 퐉 or less, and in particular, it is preferably 0.01 to 10 占 퐉, more preferably 0.01 to 5 占 퐉, and even more preferably 0.01 to 1 占 퐉.

(4) Pressure-sensitive adhesive layer

The polarizing plate 10 preferably has a pressure-sensitive adhesive layer 15 on its outermost surface. This pressure-sensitive adhesive layer can be used for bonding the polarizing plate 10 to a display element (e.g., a liquid crystal cell, an organic EL element) or another optical member, and is a pressure-sensitive adhesive layer exposed by peeling off the release film 20. Further, the pressure-sensitive adhesive layer may be used to laminate the polarizer, the protective film, the brightness enhancement film, and the retardation layer. In Fig. 1, the pressure-sensitive adhesive layer 16 corresponds to this. The pressure-sensitive adhesive layer can be composed of a pressure-sensitive adhesive composition containing as a main component a resin such as (meth) acrylic, rubber, urethane, ester, silicone or polyvinyl ether. Among them, a pressure-sensitive adhesive composition comprising a (meth) acrylic resin having excellent transparency, weather resistance and heat resistance as a base polymer is suitable. The pressure-sensitive adhesive composition may be an active energy ray-curable type or a thermosetting type.

Examples of the (meth) acrylic resin (base polymer) used in the pressure-sensitive adhesive composition include (meth) acrylates such as butyl (meth) acrylate, ethyl (meth) acrylate, isooctyl (meth) acrylate, Acrylic acid esters are preferably used as the polymer or copolymer. The base polymer is preferably copolymerized with a polar monomer. Examples of polar monomers include (meth) acrylic acid, 2-hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, (meth) acrylamide, N, N-dimethylaminoethyl A hydroxyl group, an amide group, an amino group, an epoxy group, and the like, such as dodecyl (meth) acrylate.

The pressure-sensitive adhesive composition may contain only the base polymer, but usually contains a crosslinking agent. Examples of the cross-linking agent include a metal ion having a valence of 2 or more and forming a carboxylic acid metal salt with a carboxyl group; A polyamine compound, which forms an amide bond with a carboxyl group; A polyepoxy compound or a polyol, which forms an ester bond with a carboxyl group; Is a polyisocyanate compound, and forms an amide bond with a carboxyl group. Among them, a polyisocyanate compound is preferable.

The active energy ray-curable pressure-sensitive adhesive composition has a property of curing upon irradiation with an active energy ray such as ultraviolet rays or electron rays and has adhesion even before irradiation with active energy rays and can be adhered to an adherend such as a film, And is capable of adjusting the adhesive force. The active energy ray-curable pressure-sensitive adhesive composition is preferably of ultraviolet curing type. The active energy ray-curable pressure-sensitive adhesive composition further contains an active energy ray polymerizable compound in addition to the base polymer and the crosslinking agent. If necessary, a photopolymerization initiator, a photosensitizer or the like may be contained.

The pressure-sensitive adhesive composition is preferably a pressure-sensitive adhesive composition comprising fine particles, beads (resin beads, glass beads, etc.) for imparting light scattering properties, resins other than glass fibers and base polymers, antistatic agents, tackifiers, fillers (metal powders and other inorganic powders, An antioxidant, an ultraviolet absorber, a dye, a pigment, a colorant, a defoamer, a corrosion inhibitor, a photopolymerization initiator, and the like.

The pressure-sensitive adhesive layer can be formed by applying an organic solvent diluted solution of the pressure-sensitive adhesive composition onto a substrate and drying it. The substrate may be a polarizer, a protective film, another optical film such as a brightness enhancement film, a peeling film (e.g., a peeling film 20), or the like. When an active energy ray-curable pressure-sensitive adhesive composition is used, a cured product having a desired degree of curing can be obtained by irradiating an active energy ray to the pressure-sensitive adhesive layer formed.

The thickness of the pressure-sensitive adhesive layer 15 is usually 1 to 40 占 퐉. However, from the viewpoint of thinning of the laminate and from the viewpoint of suppressing the dimensional change of the polarizing plate 10 while maintaining good processability, 20 占 퐉, more preferably 3 to 15 占 퐉). The thickness of the pressure-sensitive adhesive layer 16 is usually 1 to 20 占 퐉, preferably 3 to 10 占 퐉.

The adhesive layer 15 on which the release film 20 is laminated may have an adhesion to the release film of 0.20 N / 25 mm or less, preferably 0.10 N / 25 mm or less, more preferably 0.05 N / 25 mm Or less, and may be 0.04 or less. With such an adhesive force, peeling of the polarizing plate does not occur when the peeling film is peeled, and peelability is further improved. The adhesion is 0.02 N / 25 mm or more. With such an adhesive force, it is easy to prevent a gap from being generated between the release film and the pressure-sensitive adhesive layer even if an impact is applied to the laminate during transportation or the like. In the present specification, the adhesion of the pressure-sensitive adhesive layer to the release film is a value measured by the method described in Examples to be described later.

<Surface Protective Film>

The surface protection film 30 may include a base film 31 and a pressure-sensitive adhesive layer 32 laminated thereon. The surface protective film 30 is a film for protecting the surface of the polarizing plate 10 and usually is peeled off together with a pressure-sensitive adhesive layer it has after a laminate is bonded to a display element or another optical member.

In the surface protective film, the surface protective film is formed so that the product (K3) of the maximum force F3 (N) in the warped state and the deformation S3 (mm) when the protruding jig is vertically lowered is 0.15 N · mm More preferably 0.25 N · mm or more, and still more preferably 0.40 N · mm or more. The product K3 of the maximum force F3 (N) and the deformation S3 (mm) may be 1.00 N · mm or less, 0.90 N · mm or less, 0.80 N · mm or less, Or may be 0.60 N · mm or less. The product K3 of the maximum force F3 (N) and the strain S3 (mm) can be obtained in the same manner as the method of obtaining the product of the maximum force F1 (N) and the deformation S1 (mm).

F3 (N) may be 0.20 N or more and 1.0 N or less, and may be 0.3 N or more and 0.6 N or less. S3 (mm) may be 0.3 mm or more and 3.0 mm or less, and may be 0.5 mm or more and 2.0 mm or less.

The surface protective film is generally more elastic than the brightness enhancement film, and is important for improving the peelability of the release film. In the present specification, the thickness of the surface protective film is the total value of the thickness of the base film and the thickness of the pressure-sensitive adhesive layer laminated thereon, preferably 30 占 퐉 or more, and more preferably 50 占 퐉 or more. On the other hand, if the thickness of the surface protective film is too large, peeling easily occurs between the surface protective film and the polarizing plate when the peeling film is peeled off. Therefore, the thickness of the surface protective film is preferably 100 m or less, Or less. However, even if the thickness is the same, the product of the maximum force F3 (N) and the deformation S3 (mm) may be different depending on the material and the manufacturing method.

The base film is preferably a thermoplastic resin film. Examples of the thermoplastic resin constituting the thermoplastic resin film include polyolefin-based resins such as polyethylene-based resin and polypropylene-based resin; A cyclic polyolefin-based resin; Polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate; Polycarbonate resin; (Meth) acrylic resins, and the like. The base film may have a single-layer structure or a multi-layer structure.

The thickness of the base film may be 20 to 150 占 퐉 (e.g., 30 to 80 占 퐉, preferably 30 to 60 占 퐉). As for the constitution of the pressure-sensitive adhesive layer, the description of the pressure-sensitive adhesive layer of the above-mentioned polarizing plate is cited basically.

In particular, the pressure-sensitive adhesive layer preferably has a storage elastic modulus at 80 DEG C of 0.15 MPa or less, more preferably 0.14 MPa or less, and further preferably 0.10 MPa or less. Normally, the pressure-sensitive adhesive layer has a storage elastic modulus at 80 캜 of 0.01 MPa or more. In the present specification, the storage elastic modulus of the pressure-sensitive adhesive layer can be measured using a commercially available viscoelasticity measuring device, for example, a viscoelasticity measuring device "DYNAMIC ANALYZER RDA II" manufactured by REOMETRIC.

The surface protection film 30 may contain an antistatic agent. The antistatic agent can be contained in the pressure-sensitive adhesive layer, for example. Instead of or in combination with the antistatic agent in the pressure-sensitive adhesive layer, an antistatic layer containing an antistatic agent may be formed on a surface of the base film opposite to the surface on which the pressure-sensitive adhesive layer is laminated.

As the antistatic agent, an ionic compound may be mentioned. The ionic compound is a compound having an inorganic or organic cation and an inorganic or organic anion. Two or more kinds of ionic compounds may be used.

<Peeling film>

The release film 20 is a film temporarily adhered to protect the surface of the adhesive layer until it is bonded to a display element (e.g., a liquid crystal cell, an organic EL element) or another optical member. The peeling film 20 can be adjusted in adhesion with the pressure-sensitive adhesive layer 15 by subjecting the one surface to a releasing treatment with a releasing agent such as silicone or fluorine. The release film 20 is composed of a thermoplastic resin film subjected to release treatment, and a pressure-sensitive adhesive layer can be bonded to the release-treated surface.

The thermoplastic resin constituting the release film 20 can be, for example, a polyethylene-based resin such as polyethylene, a polypropylene-based resin such as polypropylene, a polyester-based resin such as polyethylene terephthalate or polyethylene naphthalate. The thickness of the peeling film 20 is, for example, 10 to 50 占 퐉.

The laminated films 100 to 103 can be peeled off the release film 20 and bonded to a display element (for example, a liquid crystal cell or an organic EL element). Further, the surface protection film 30 can be peeled off and incorporated into a display device (e.g., a liquid crystal display device, an organic EL display device). When the display device is constructed, the stacked bodies 100 to 103 according to the present invention may be used for a polarizing plate disposed on the viewer side or for a polarizing plate disposed on the backlight side, and both polarizers on the viewer side and the backlight side .

For example, the release film can be peeled off from the laminate in the following manner. The surface of the laminate on the side of the surface protective film is fixed to the supporter, and the peeling tape is bonded on the peeling film. The method of fixing the laminate is not particularly limited and may be fixed by suction force from the surface protective film side or by adhesive force. The adhesion between the surface protective film to be fixed and the holding table is preferably 0.1 to 0.3 N / 60 mm, more preferably 0.15 to 0.2 N / 60 mm from the viewpoint of not leaving traces on the polarizing plate. According to the laminate of the present invention, even if the laminate is fixed with such a small pressure, good releasability is exhibited. The position at which the peeling tape is joined is not particularly limited. When the laminate is rectangular, it can be bonded to any one of the four corners (diagonal portion), or to the center of any one of the four sides. The peeling tape may be bonded to one portion of the peeling film or may be bonded to a plurality of portions. Subsequently, a peeling tape is raised to peel off the peeling film. The peeling angle can be 90 to 180 DEG, and the peeling speed can be 0.1 to 10 m / min.

[Example]

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

(1) Measurement method of rigidity (F x S)

The maximum force F (N) and strain S (mm) in the bent state of each film were measured using KES-G5, a compression tester manufactured by Kato Tech Co., Ltd., and the product of these was calculated. 3 and 4, will be described in detail. The size of the measuring film 3 was a rectangle having a short side 25 mm (both arrow 43) and a long side 43 mm (both arrows 42). In the protruding jig 1, a needle having a spherical tip, a tip diameter of 1 mm phi, and a curvature of 0.5 R was used. The film 3 to be measured is placed on the table 2 as shown in Fig. 3, and the protruding jig 1 is lowered perpendicularly to the film 3. As shown in Fig. A circular hole extending from the upper surface to the lower surface is formed in the base 2 on which the film 3 is placed and the upper hole diameter (both arrows 44) is 30 mm and the lower hole diameter (41) is 10 mm. The load on the protruding jig 1 was 1 kg, and the descending speed of the protruding jig was 1.0 cm / sec. After the protruding jig 1 is brought into contact with the film 3 to be measured, the maximum load N and the deformation (Fig. 4 (a)) in the state in which the film is bent (in a state immediately before wrinkle or folding occurs) (Length of both arrows 40) (mm).

(2) Method of measuring film thickness

Was measured using MH-15M, a digital micrometer manufactured by Nikon Corporation.

(3) Method of measuring adhesion

Using Autograph (registered trademark) AGS-X, a tabletop type precision universal testing machine manufactured by Shimadzu Seisakusho Co., Ltd., adhesion between the peeling film and the pressure-sensitive adhesive layer of the polarizing plate was measured.

(4) Evaluation method of peelability of release film

The laminate produced in each of the examples was fixed to a glass plate (support base) so that the surface protective film was positioned on the lower side. A pressure-sensitive adhesive sheet was used for fixation, and the fixation force (adhesion) was 0.1 to 0.3 N / 60 mm. A peeling tape was bonded to one of four corners of the peeling film so that the long side direction of the peeling tape was parallel to the long side direction of the laminate. As the release tape, No. 315, which is a polyester adhesive tape manufactured by Nitto Denko Corporation, was used and the width was 12 mm and the length of the joined portion was 10 mm. One end of the peeling tape was gripped with a chuck, and the peeling film was peeled off. The peeling speed was 3 m / min, and the peeling angle was 180 °. The case where the layer made of the polarizing plate and the surface protective film floated from the glass on which the laminate was fixed was judged as the peeling failure (NG) and the peeling film could be peeled without floating. Respectively.

[Example 1]

A laminate was produced as follows.

A polarizer (thickness: 5 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. A cycloolefin resin (COP) film (thickness: 30 占 퐉, manufactured by Nippon Zeon Co., Ltd.) having a hard coat layer formed thereon was bonded to one surface of the polarizer through an ultraviolet curable adhesive, A retardation layer (thickness of 20 mu m) made of a cyclic olefin resin was bonded through an adhesive.

Subsequently, a retardation layer (thickness: 5 mu m) including a layer in which the polymerizable liquid crystal compound was cured was formed on the cycloolefin resin film. An acrylic pressure-sensitive adhesive layer (thickness: 20 mu m) was formed on a release film (thickness of 38 mu m) made of a polyester-based resin film, and this acrylic pressure-sensitive adhesive layer was laminated on the retardation layer. Sensitive adhesive layer (thickness: 65 mu m as a total of the base film and the acrylic pressure-sensitive adhesive layer) consisting of a base film (thickness 50 mu m) made of a polyester resin and an acrylic pressure-sensitive adhesive layer (thickness 15 mu m) Was laminated on the cycloolefin resin film provided with the hard coat layer to obtain a film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a COP film / surface protective film formed with a release film / pressure-sensitive adhesive layer / retardation layer (layer in which a liquid crystal compound was cured) / retardation layer (COP film) / polarizer / hard coat layer. The thickness of the polarizing plate (pressure-sensitive adhesive layer / retardation layer (layer of cured liquid crystal compound) / retardation layer (COP film) / polarizer / hard coat layer formed in this laminate] was 80 占 퐉 and the thickness Was 38 탆, and the thickness of the surface protective film was 65 탆.

Further, a release film (38 占 퐉) was peeled from the film obtained above to leave a pressure-sensitive adhesive layer to obtain a layer comprising a polarizing plate and a surface protective film. The layer was cut into a rectangle of 25 mm 占 43 mm, ), And the maximum force F in the warped state was measured by the above-mentioned measuring method, and the strain (S) was measured to be S1.

A polarizing plate (thickness: 80 占 퐉) was obtained by peeling off the release film (thickness of 38 占 퐉) and the surface protective film (thickness of 65 占 퐉) from the obtained film leaving the pressure-sensitive adhesive layer. The maximum force F in the warped state is measured to be F2 and the maximum strain S in the warped state is measured And S2. The surface protective film used above was cut out into a rectangular shape of 25 mm x 43 mm and used as a measurement film. The maximum force F in the bent state was measured by the above measuring method to obtain F3, The strain (S) was measured to be S3. As a result, F1 = 2.69 N, S1 = 3.4 mm, F2 = 0.52 N, S2 = 1.1 mm, F3 = 0.46 N and S3 = 1.6 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.04 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Example 2]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. On one surface of the polarizer, a cyclic olefin based resin film (manufactured by Nippon Zeon Co., Ltd., thickness 30 μm) having a hard coat layer formed thereon was adhered via an aqueous adhesive. (Trade name: FS-PF, manufactured by Fujimori Kogyo K.K.) comprising a base film (thickness 38 占 퐉) made of a polyester resin and an acrylic pressure-sensitive adhesive layer (thickness 17 占 퐉) And then laminated on a cyclic olefin based resin film having a hard coat layer formed thereon.

The following laminated film was bonded to the other side of the polarizer through an ultraviolet curing adhesive. This laminated film was formed on a retardation layer (thickness: 20 占 퐉, in-plane retardation value Re (590) = 120 to 150 nm, made by Nippon Zeon Co., Ltd.) comprising a cyclic olefin based resin film, (Thickness: 1 mu m, retardation value Rth (590) in the thickness direction = -10 1 to -150 nm) are stacked. And the joining surfaces to the polarizers were joined so as to be the COP film surface of the laminated film.

An acrylic pressure-sensitive adhesive layer (Lintec Corp., thickness: 13 占 퐉, # KC1) was formed on a release film (thickness 38 占 퐉) made of a polyester-based resin film and the acrylic pressure-sensitive adhesive layer was laminated on the retardation layer.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a COP film / surface protective film formed with a release film / pressure-sensitive adhesive layer / retardation layer (layer in which a liquid crystal compound was cured) / retardation layer (COP film) / polarizer / hard coat layer. The thickness of the polarizing plate was 72 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 55 占 퐉.

Further, F1 = 2.23 N, S1 = 2.6 mm, F2 = 0.56 N, S2 = 1.5 mm, F3 = 0.30 N, and S3 = 0.7 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.02 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Example 3]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. On one surface of the polarizer, a cyclic olefin based resin film (manufactured by Nippon Zeon Co., Ltd., thickness 30 μm) having a hard coat layer formed thereon was adhered via an aqueous adhesive. (Trade name: FS-PF, manufactured by Fujimori Kogyo K.K.) comprising a base film (thickness 38 占 퐉) made of a polyester resin and an acrylic pressure-sensitive adhesive layer (thickness 17 占 퐉) And then laminated on a cyclic olefin based resin film having a hard coat layer formed thereon.

The following laminated film was bonded to the other side of the polarizer through an ultraviolet curable adhesive. This laminated film was laminated on a phase difference layer (22 mu m in thickness, in-plane retardation value Re (590) = 120 to 150 nm, made by Nippon Zeon Co., Ltd.) comprising a cyclic olefin based resin film, (Thickness: 1 mu m, retardation value Rth (590) in the thickness direction = -10 1 to -150 nm) are stacked. And the joining surfaces to the polarizers were joined so as to be the COP film surface of the laminated film. (Thickness: 13 占 퐉, # KC1, manufactured by LINTEC CORPORATION) was formed on a release film (thickness of 38 占 퐉) made of a polyester-based resin film having a silicon amount smaller than that of Example 2 and the acrylic pressure- Was laminated on the retardation layer.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a COP film / surface protective film formed with a release film / pressure-sensitive adhesive layer / retardation layer (layer in which a liquid crystal compound was cured) / retardation layer (COP film) / polarizer / hard coat layer. The thickness of the polarizing plate was 74 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 55 占 퐉.

Further, F1 = 2.15 N, S1 = 3.4 mm, F2 = 0.61 N, S2 = 1.6 mm, F3 = 0.30 N, and S3 = 0.7 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.04 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Example 4]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. A brightness enhancement film (APF-V3, manufactured by 3M, thickness: 30 占 퐉) was bonded to one surface of the polarizer through a pressure-sensitive adhesive layer (thickness: 5 占 퐉), and the other surface of the polarizer was bonded with an ultraviolet- And a cycloolefin resin film (manufactured by Nippon Zeon Co., Ltd., thickness: 13 占 퐉) was bonded. Sensitive adhesive layer was laminated on the cyclic olefin-based resin film, and an acrylic pressure-sensitive adhesive layer (Lintec Corp., thickness 13 占 퐉, # KC1) was formed on a release film (thickness 38 占 퐉) comprising a polyester- . A surface protective film (OF-PF, trade name, manufactured by EYE KABUN CO., LTD.) Comprising a base film (thickness 38 占 퐉) made of a polyester resin and an acrylic pressure sensitive adhesive layer (thickness 15 占 퐉) was prepared and the acrylic pressure sensitive adhesive layer And laminated on the brightness enhancement film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a release film / pressure-sensitive adhesive layer / COP film / polarizer / pressure-sensitive adhesive layer / brightness enhancement film / surface protective film. The thickness of the polarizing plate was 69 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 53 占 퐉.

Further, F1 = 1.62 N, S1 = 3.5 mm, F2 = 0.61 N, S2 = 1.6 mm, F3 = 0.21 N and S3 = 0.7 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.02 N / 25 mm, and no peeling was observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like

[Example 5]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. A brightness enhancement film (APF-V4, thickness: 20 占 퐉, manufactured by 3M Company) was bonded to one side of the polarizer via a pressure-sensitive adhesive layer (thickness: 15 占 퐉), and the other side of the polarizer was bonded with an ultraviolet- And a cycloolefin resin film (manufactured by Nippon Zeon Co., Ltd., thickness: 13 占 퐉) was bonded. Sensitive adhesive layer was laminated on the cyclic olefin-based resin film, and an acrylic pressure-sensitive adhesive layer (Lintec Corp., thickness 13 占 퐉, # KC1) was formed on a release film (thickness 38 占 퐉) comprising a polyester- . (FY-PF, trade name, manufactured by Fujimori Kogyo K.K.) comprising a base film (thickness 50 占 퐉) made of a polyester resin and an acrylic pressure-sensitive adhesive layer (thickness 15 占 퐉) And laminated on a luminance enhancement film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a release film / pressure-sensitive adhesive layer / COP film / polarizer / pressure-sensitive adhesive layer / brightness enhancement film / surface protective film. The thickness of the polarizing plate was 69 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 65 占 퐉.

Further, F1 = 1.62 N, S1 = 2.4 mm, F2 = 0.25 N, S2 = 0.7 mm, F3 = 0.42 N, and S3 = 1.3 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.02 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Comparative Example 1]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. In the production of the polarizer, the stretching magnification was made higher than that of the polarizer of Example 5. [ A brightness enhancement film (APF-V4, thickness: 20 占 퐉, manufactured by 3M Company) was bonded to one side of the polarizer via a pressure-sensitive adhesive layer (thickness: 15 占 퐉), and the other side of the polarizer was bonded with an ultraviolet- And a cycloolefin resin film (manufactured by Nippon Zeon Co., Ltd., thickness: 13 占 퐉) was bonded. Sensitive adhesive layer was laminated on the cyclic olefin-based resin film, and an acrylic pressure-sensitive adhesive layer (Lintec Corp., thickness 13 占 퐉, # KC1) was formed on a release film (thickness 38 占 퐉) comprising a polyester- . A surface protective film (trade name: AY-XA35, manufactured by Fujimori Kogyo K.K.) comprising a base film (thickness 38 占 퐉) made of a polyester resin and an acrylic pressure sensitive adhesive layer (thickness 15 占 퐉) was prepared and the acrylic pressure sensitive adhesive layer And laminated on a luminance enhancement film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a release film / pressure-sensitive adhesive layer / cycloolefin resin film / polarizer / pressure-sensitive adhesive layer / brightness enhancement film / surface protective film. The thickness of the polarizing plate was 69 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 53 占 퐉.

Further, F1 = 1.09 N, S1 = 2.1 mm, F2 = 0.24 N, S2 = 0.6 mm, F3 = 0.22 N and S3 = 0.5 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.02 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Comparative Example 2]

A laminate was produced as follows.

A polarizer (thickness 8 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. A brightness enhancement film (APF-V4 manufactured by 3M, thickness: 20 占 퐉) was bonded to one side of the polarizer through a pressure-sensitive adhesive layer (thickness: 15 占 퐉). On the other side of the polarizer, Based resin film (manufactured by Nippon Zeon Co., Ltd., thickness 13 占 퐉). Sensitive adhesive layer was laminated on the cyclic olefin-based resin film, and an acrylic pressure-sensitive adhesive layer (Lintec Corp., thickness 13 占 퐉, # KC1) was formed on a release film (thickness 38 占 퐉) comprising a polyester- . A surface protective film (trade name: AY-XA35, manufactured by Fujimori Kogyo K.K.) comprising a base film (thickness 38 占 퐉) made of a polyester resin and an acrylic pressure sensitive adhesive layer (thickness 15 占 퐉) was prepared and the acrylic pressure sensitive adhesive layer And laminated on a luminance enhancement film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a release film / pressure-sensitive adhesive layer / cycloolefin resin film / polarizer / pressure-sensitive adhesive layer / brightness enhancement film / surface protective film. The thickness of the polarizing plate was 69 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 53 占 퐉.

Further, F1 = 1.21 N, S1 = 1.8 mm, F2 = 0.25 N, S2 = 0.7 mm, F3 = 0.25 N and S3 = 0.5 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.02 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

[Comparative Example 3]

A laminate was produced as follows.

A polarizer (thickness: 5 占 퐉) in which iodine was adsorbed and oriented on a polyvinyl alcohol-based resin was prepared. A brightness enhancement film (APF-V4, thickness 20 占 퐉, manufactured by 3M Company) was bonded to one side of the polarizer through a pressure-sensitive adhesive layer (thickness: 5 占 퐉). On the other side of the polarizer, (Thickness: 20 mu m). An acrylic pressure-sensitive adhesive layer (thickness: 21 mu m) was formed on a release film (thickness of 38 mu m) made of a polyester-based resin film, and this acrylic pressure-sensitive adhesive layer was laminated on the protective film made of the acrylic resin. A surface protective film comprising a base film (thickness: 40 占 퐉) made of a polyester resin and an acrylic pressure sensitive adhesive layer (thickness: 16 占 퐉) was prepared and the acrylic pressure sensitive adhesive layer was laminated on the brightness enhancement film.

The resulting film was cut into rectangles with a long side of 26.6 cm and a short side of 20.0 cm to obtain a laminate. The laminate had a layer structure of a release film / pressure-sensitive adhesive layer / optical protective film / polarizer / pressure-sensitive adhesive layer / brightness enhancement film / surface protective film. The thickness of the polarizing plate was 71 占 퐉, the thickness of the release film was 38 占 퐉, and the thickness of the surface protective film was 56 占 퐉.

F1 = 1.55 N, S1 = 2.3 mm, F2 = 0.24 N, S2 = 1.3 mm, F3 = 0.21 N and S3 = 1.1 mm.

The adhesion between the pressure-sensitive adhesive layer and the release film was 0.04 N / 25 mm, and peeling was not observed between the pressure-sensitive adhesive layer and the release film due to transportation or the like.

The laminate produced in Examples 1 to 5 and Comparative Examples 1 to 3 was evaluated for peelability. The results are shown in Table 1. As shown in Table 1, the laminate of Examples 1 to 5 was able to satisfactorily peel off the release film. Also in any of the examples, there was no defective peeling between the polarizing plate and the surface protective film.

According to the present invention, even a polarizing plate having low rigidity is useful because it can provide a laminate which does not cause peeling failure of the release film.

1: stone jig 2: stand
3: Film to be measured 10: Polarizer
11: polarizer 12, 13: protective film
14: Brightness improving film 15: Pressure sensitive adhesive layer
16: pressure-sensitive adhesive layer 17: retardation layer
20: peeling film 30: surface protective film
31: base film 32: pressure-sensitive adhesive layer
40, 41, 42, 43, 44: double arrows 100, 101, 102, 103:

Claims (4)

A surface protective film is peelably laminated on one surface of the polarizing plate,
A peeling film is peelably laminated on the other surface of the polarizing plate via a pressure-sensitive adhesive layer,
Wherein the polarizer includes a polarizer,
The maximum force F3 (N (N)) is obtained when F3 is the maximum force F (N) measured by the following measuring method, and S3 is the strain (S And a stiffness K3 expressed as a product (F3 (N) xS3 (mm)) of a deformation S3 (mm)
The maximum force (F (N)) measured by the following measuring method was F1 and the deformation (S (mm)) was S1, with the layer comprising the polarizing plate and the surface protecting film as the measuring film And a rigidity K1 expressed by a product F1 (N) x S1 (mm) of a maximum force F1 (N) and a deformation S1 (mm) is 3.70 N · mm or more and 10.0 N · mm or less.
How to measure:
The measurement table has a circular through-hole at its center as viewed from the upper surface, a diameter of the through-hole at the upper surface is 30 mm, and the shape of the through hole viewed from the side is a shape composed of a columnar lower portion and a hemispherical upper portion ,
A rectangular measurement film of 25 mm x 43 mm was placed,
A needle having a spherical tip, a tip diameter of 1 mm phi and a radius of curvature of 0.5 mm was vertically dropped from above the measurement film at a rate of 1.0 cm / sec so that the needle passed through the center of the through hole of the measurement bench ,
After the tips of the needles contact the measuring film, the maximum load at which the film keeps bent is measured as the maximum force F (N), and the strain S (mm) of the film at that time is measured. The optical film according to claim 1, wherein when the polarizing plate is used as a measurement film, the maximum force F (N) measured by the measuring method is F2 (N), and the deformation S (mm) And a stiffness K2 expressed by a product of a force F2 (N) and a deformation S2 (mm) of 1.00 N · mm or less. The laminate according to claim 1 or 2, wherein the adhesive force between the polarizing plate and the release film is 0.02 to 0.05 N / 25 mm. A step of fixing the surface protective film in the laminate according to any one of claims 1 to 3 to a holding table with an adhesion force of 0.1 to 0.3 N / 60 mm;
A step of peeling off the release film from the laminate
Wherein the polarizing plate is a polarizing plate.

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