TWI655461B - Laminated polarizing film, manufacturing method thereof, laminated optical film and image display device - Google Patents

Abstract

The laminated polarizing film of the present invention is a laminated polarizing film formed by laminating a polarizing film and an optical film other than a polarizer with a low-elasticity adhesive layer (a), wherein the polarizing film is passed through the adhesive layer (b) on the A transparent protective film is laminated on at least one side of the polarizer, and the transparent protective film is laminated with the aforementioned low elasticity adhesive layer (a), and the low elasticity adhesive layer (a) has a storage elastic modulus at 25 ° C. The thickness is 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa, and the thickness of the low-elasticity adhesive layer (a) is 0.1 to 5 μm . The laminated polarizing film of the present invention has good impact resistance and thermal buckling resistance.

Description

Laminated polarizing film, manufacturing method thereof, laminated optical film and image display device Technical field

The present invention relates to a laminated polarizing film and a method for manufacturing the laminated polarizing film. The laminated polarizing film is formed by laminating a polarizing film and an optical film other than a polarizer by using a low-elastic adhesive layer. The laminated film may be an image display device such as a liquid crystal display device (LCD), an organic EL display device, a CRT, a PDP, etc., alone or as a laminated optical film formed by further laminating optical films.

Background technique

For liquid crystal display devices and the like, it is necessary to arrange polarizing elements on both sides of the liquid crystal cell by its image formation method, and generally, a polarizing film is attached. In addition, in order to improve the display quality of the display, various optical films other than polarizing films are used in the liquid crystal panel. For example, optical films are used: retardation films to prevent coloring, viewing angle expansion films to improve the viewing angle of liquid crystal displays, and brightness enhancement films to improve the contrast of displays.

When the polarizing film and the optical film (such as a retardation film) are combined to form a laminated polarizing film, it is usually laminated with an adhesive layer. Layer of the aforementioned polarizing film and optical film (for example, Patent Document 1). Patent Literature 1 proposes an adhesive layer having a storage elastic modulus at 23 ° C. of 0.3 MPa or more from the viewpoint of preventing light leakage and the like. Further, in Patent Document 1, in order to satisfy the peeling force of the adhesive layer, an adhesive layer having a thickness of 5 to 100 μm is used.

Know-how Patent literature

[Patent Document 1] Japanese Patent Laid-Open No. 2008-032852

Summary of invention

Since the retardation film used in the laminated polarizing film is aligned with a molecular system surface in the film, it is easily cracked due to shock such as dropping. Therefore, for example, the impact resistance of a laminate of a polarizing film and a retardation film is insufficient.

The laminated polarizing film is used for a heating test, a freeze cycle test (thermal shock cycle test), and the like in a state where the liquid crystal cell is adhered to form a panel. However, in the adhesive layer described in Patent Document 1, it is difficult for the adhesive layer to conform to the dimensional change of the polarizing film caused by the aforementioned test, and the laminated layer after the test is observed in a crossed nicol state. In a polarizing film, display defects such as uneven stripes are observed. Therefore, the laminated optical film system is pursuing stripe unevenness and the like in a state in which the laminated polarizing film does not cause the cross-Nicol otoscope even after the above-mentioned test (hereinafter referred to as thermal flexibility).

An object of the present invention is to provide a laminated polarizing film formed by laminating a polarizing film and an optical film other than the polarizing film, and a method for manufacturing the same. The laminated polarizing film is a laminated polarizing film with good impact resistance and thermal bending resistance.

In addition, an object of the present invention is to provide a laminated optical film using the aforementioned laminated polarizing film, and also to provide an image display device using the aforementioned laminated polarizing film or laminated optical film.

The present inventors made intensive studies in order to solve the aforementioned problems, and found that the aforementioned problems can be solved by the following polarizing film or the like, and thus completed the present invention.

That is, the present invention relates to a laminated polarizing film, which is characterized in that it is a laminated polarizing film formed by laminating a polarizing film and an optical film other than a polarizer by a low-elasticity adhesive layer (a), wherein the aforementioned The polarizing film is laminated with a transparent protective film on at least one side of the polarizer through the adhesive layer (b), and the transparent protective film is laminated with the aforementioned low elasticity adhesive layer (a) and the aforementioned low elasticity adhesive layer (a ) The storage elastic modulus at 25 ° C. is 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa, and the thickness of the aforementioned low elastic adhesive layer (a) is 0.1 to 5 μm.

In the aforementioned laminated optical film, a retardation film can be used as the aforementioned optical film.

In the laminated optical film, the low-elasticity adhesive layer (a) is preferably a hardened material layer obtained by irradiating an active energy ray-curable adhesive with an active energy ray.

In the laminated optical film, the active energy ray-curable adhesive is preferably a liquid substance that does not substantially contain an organic solvent and has a viscosity of 1 to 100 cp / 25 ° C.

In the laminated optical film, the active energy ray-curable adhesive preferably contains a radical polymerizable compound as a curable component.

In the laminated optical film, the radical polymerizable compound preferably contains a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound (A). When the total amount of the radical polymerizable compound is 100% by weight, the proportion of the polyfunctional radical polymerizable compound (A) is preferably 1 to 65% by weight. The polyfunctional radically polymerizable compound (A) is preferably a bifunctional (meth) acrylate having a weight average molecular weight of 200 to 4000.

In the multilayer optical film, the radical polymerizable compound preferably includes an alkyl (meth) acrylate (B) having an alkyl group having 2 to 18 carbon atoms.

In the laminated optical film, the radical polymerizable compound preferably contains a (meth) acrylate (C) having a hydroxyl group. The (meth) acrylate (C) having a hydroxyl group is preferably a hydroxyl-containing monofunctional (meth) acrylate having a weight average molecular weight of 160 to 3000.

In the laminated optical film, the active energy ray-curable adhesive preferably contains a silane coupling agent (D). The silane coupling agent (D) is preferably a silane coupling agent having no radical polymerizable functional group.

In the laminated optical film, the active energy ray hardening type The adhesive preferably contains an acrylic oligomer (E) obtained by polymerizing a (meth) acrylic monomer.

In the laminated optical film, the active energy ray-curable adhesive preferably includes a radical polymerizable compound (F) having an active methylene group and a radical polymerization initiator (G) having a hydrogen abstraction effect. The aforementioned active methylene group is preferably acetamidine. The radically polymerizable compound (F) having a living methylene group is preferably acetoacetoxyalkyl (meth) acrylate.

In the laminated optical film, the radical polymerization initiator (G) is 9-oxysulfur It is preferably a radical polymerization initiator.

In the laminated optical film, the adhesive layer (b) may use an adhesive layer (b1) having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness satisfying 0.03 to 3 μm. .

In the laminated optical film, when the polarizing film is provided with the transparent protective film on both sides of the polarizer through the adhesive layer (b), any of the adhesive layer (b) may be used. The adhesive layer (b1) having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness satisfying 0.03 to 3 μm.

In the laminated optical film, when the polarizing film is provided with the transparent protective film on both sides of the polarizer through the adhesive layer (b), the single-sided adhesive layer (b) may be used in Adhesive layer (b1) having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness of 0.03 to 3 μm, and the aforementioned adhesive layer (b) on the other side is at 85 ° C. The adhesive elastic layer (b2) having a storage elastic modulus of 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa and a thickness satisfying 0.1 to 25 μm.

In the laminated optical film, the thickness of the polarizer is preferably 1 to 10 μm.

In the laminated optical film, the transparent protective film uses a retardation film as a transparent protective film on at least one side.

When the laminated optical film is forcibly peeled from the polarizing film and the optical film, it is preferable that the low-elasticity adhesive layer (a) is to cause failure of a cement.

The peeling force of the laminated optical film when the polarizing film and the optical film are forcibly peeled is 1 to 5 N / 15 mm.

In addition, the present invention also relates to a method for manufacturing a laminated polarizing film, which is characterized in that it is a method for manufacturing the aforementioned laminated polarizing film. The manufacturing method includes the following steps: a coating step, which is to be laminated in the aforementioned polarizing film, At least one side of the transparent adhesive film on the elastic adhesive layer (a) side and the optical film is coated with an active energy ray-curable adhesive agent forming the aforementioned low elastic adhesive layer (a); the bonding step is to adhere the aforementioned polarizing film And the aforementioned optical film; and a step of adhering the polarizing film and the aforementioned optical film by a low-elasticity adhesive layer (a), wherein the low-elasticity adhesive layer (a) is by irradiating the aforementioned active energy rays, The active energy ray-curable adhesive is hardened.

In the method for manufacturing the laminated polarizing film, the integrated illuminance and the integrated illuminance of the active energy rays in the wavelength range of 380 to 440 nm and The ratio of the accumulated illuminance in the wavelength range of 250 to 370 nm is preferably 100: 0 to 100: 50.

The present invention also relates to a laminated optical film, which is characterized in that at least one of the aforementioned laminated polarizing films is laminated.

The present invention also relates to an image display device, characterized in that the laminated polarizing film or the laminated optical film is used.

The laminated polarizing film of the present invention is an optical film other than a polarizing film and a polarizing member laminated with a low-elasticity adhesive layer (a). The purpose of the adhesive layer is to laminate and fix the films to each other, which is different from the adhesive layer provided that the films can be peeled off after the films are laminated to each other. The said low elasticity adhesive layer (a) adhere | attaches a polarizing film and an optical film firmly. Such a low-elasticity adhesive layer (a) can maintain the peeling force between films more than a predetermined value even in the thickness of a thin layer (0.1-5 micrometers), and can satisfy the thermal-flexibility. Furthermore, a thin layer (0.1 to 5 μm) of the adhesive layer cannot satisfy the peeling force. Although the adhesive layer can obtain a predetermined peeling force by thickening the thickness, once the thickness of the adhesive layer becomes thick, the adhesive layer becomes difficult to conform to the dimensional change of the polarizing film caused by the heating test and the freeze cycle test. , And can not meet the thermal buckling.

In addition, the low-elasticity adhesive layer (a) of the present invention controls the storage elastic modulus at 25 ° C to 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa, so the low-elasticity adhesive layer (a) is a thin layer. Still, the impact resistance of the laminated polarizing film is still good.

In addition, when the laminated polarizing film of the present invention is a thin polarizer having a thickness of 1 to 10 μm, the polarizing film constituting the polarizing film is thermally buckled. It is particularly effective in terms of properties and impact resistance. Due to the small dimensional change of the thin polarizer described above, the dimensional change of transparent protective films and optical films other than polarizers will be relatively large. Compared with polarizers with a thickness of 10 μm or more, it is thermally flexible. There will be a worse tendency. In addition, since a thin polarizer has a high elastic modulus compared to a polarizer having a thickness of 10 μm or more, it has a tendency to be inferior in shock absorption compared to a polarizer having a thickness of 10 μm or more. If the laminated polarizing film according to the present invention has a low-elasticity adhesive layer (a), even when a thin polarizer is used, it can still satisfy thermal buckling and impact resistance.

1‧‧‧Polarizer

2‧‧‧ transparent protective film

P, P1, P2, P3‧‧‧polarized film

3‧‧‧ Optical Film (Phase Difference Film)

a, a1, a2‧‧‧Low elastic adhesive layer

b, b1, b2‧‧‧Adhesive layer

FIG. 1A shows a cross-sectional view of an embodiment of the laminated polarizing film of the present invention.

FIG. 1B shows a cross-sectional view of an embodiment of the laminated polarizing film of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the laminated polarizing film of the present invention.

FIG. 3 is a cross-sectional view showing an embodiment of the laminated polarizing film of the present invention.

FIG. 4 is a cross-sectional view showing an embodiment of the laminated polarizing film of the present invention.

Forms used to implement the invention

An embodiment of the laminated polarizing film of the present invention will be described below with reference to the drawings.

1 to 4 are cross-sectional views showing an embodiment of the laminated polarizing film of the present invention. The laminated polarizing film shown in FIG. 1A has a polarizing film having a transparent protective film (2) on both sides of a polarizer (1) through an adhesive layer (b). (P), and an optical film (3) is provided on the transparent protective film (2) on one side of the polarizing film (P) by a low-elasticity adhesive layer (a). The laminated polarizing film shown in FIG. 1B has a polarizing film (P) provided with a transparent protective film (2) only on one side of the polarizer (1) through an adhesive layer (b), and the polarizing film (P) The transparent protective film (2) is provided with an optical film (3) through a low-elasticity adhesive layer (a). Furthermore, although the optical film (3) is provided on the transparent protective film (2) on one side of the polarizing film (P) only with a low-elastic adhesive layer (a) in FIG. 1A, transparent protection on both sides is also possible. An optical film (3) is provided on the film (2) with a low-elasticity adhesive layer (a). The laminated polarizing films of FIGS. 2 to 4 show a case where the polarizing films (P) described in FIG. 1A are used in the state of the polarizing films (P1) to (P3).

The storage elastic modulus of the low-elasticity adhesive layer (a) at 25 ° C. is 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa. By controlling the storage elastic modulus of the low-elasticity adhesive layer (a) at 25 ° C within the aforementioned range, a laminated polarizing film having good impact resistance and thermal buckling resistance can be obtained. When the storage elastic modulus at 25 ° C. is less than 3.0 × 10 ⁵ Pa, it is not suitable because sufficient cohesive force of the low-elasticity adhesive layer (a) cannot be obtained and the adhesiveness is reduced. On the other hand, when the storage elastic modulus at 25 ° C. is higher than 1.0 × 10 ⁸ Pa, it is not suitable from the viewpoint of impact resistance because of poor impact absorption. The storage elastic modulus at 25 ° C is preferably 1.0 × 10 ⁶ to 1.0 × 10 ⁷ Pa.

The storage elastic modulus of the low-elasticity adhesive layer (a) at 85 ° C is preferably 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa. By controlling the storage elastic modulus of the low-elasticity adhesive layer (a) at 85 ° C. to be in the aforementioned range, it is suitable because heating durability can be satisfied. In particular, by making the storage elastic modulus at 85 ° C higher than 3.0 × 10 ⁵ Pa, foaming and peeling due to vapor pressure caused by vaporization of residual moisture such as polarizing films and optical films can be suppressed. The production is therefore more appropriate. Further, by making the storage elastic modulus at 85 ° C. less than 1.0 × 10 ⁸ Pa, it is preferable to suppress peeling of the adhesive layer caused by dimensional changes of the polarizing film, optical film, and the like. The storage elastic modulus at 85 ° C is preferably 1.0 × 10 ⁶ to 1.0 × 10 ⁷ Pa.

The thickness of the low-elasticity adhesive layer (a) is 0.1 to 5 μm. The low-elasticity adhesive layer (a) can form a thin layer, and even if it is a thin layer, the aforementioned storage elastic modulus can be satisfied, and a laminated polarizing film with good thermal buckling properties can be obtained. When the thickness is less than 0.1 μm, it is not suitable because the cohesive force of the low-elasticity adhesive layer (a) cannot be sufficiently obtained and the adhesive force is reduced. On the other hand, when the thickness is more than 5 μm, it is not suitable because the thermal buckling property is deteriorated. From the viewpoint of a thin layer, the thickness of the aforementioned low-elasticity adhesive layer (a) is preferably 0.4 to 3 μm, and more preferably 0.7 to 2 μm.

On the other hand, in the polarizing film (P) or (P ' ), the thickness of the adhesive layer (b) of the laminated polarizer (1) and the transparent protective film (2) is usually 0.1 from the viewpoint of adhesiveness. ~ 25μm.

The polarizing film (P1) in the laminated polarizing film of FIG. 2 is a case where the adhesive layer (b1) is used on either side of the adhesive layer (b) on both sides of the polarizer (1). The adhesive layer (b1) may be one having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness satisfying 0.03 to 3 μm. It is preferable to control the storage elastic modulus and thickness of the adhesive layer (b1) within the foregoing ranges from the viewpoint of suppressing cracks in the polarizer during a thermal shock cycle test. The storage elastic modulus of the aforementioned adhesive layer (b1) at 85 ° C is preferably 1.0 × 10 ⁷ to 5.0 × 10 ⁹ Pa, and more preferably 1.0 × 10 ⁸ to 1.0 × 10 ⁹ Pa. From the viewpoint of a thin layer, the thickness of the adhesive layer (b1) is preferably 0.04 to 2 μm, and more preferably 0.05 to 1.5 μm.

The storage elastic modulus of the adhesive layer (b1) at 25 ° C is 5.0 × 10 ⁷ to 1.0 × 10 ¹⁰ Pa, preferably 1.0 × 10 ⁸ to 7.0 × 10 ⁹ Pa, and 5.0 × 10. ⁸ to 5.0 × 10 ⁹ Pa is more preferable.

The polarizing films (P2) and (P3) in the laminated polarizing films of FIGS. 3 and 4 use an adhesive layer (b1) as the adhesive layer (b) on one side of the polarizer (1), and use the adhesive layer ( b2) The case of the aforementioned adhesive layer (b) on the other side. In FIG. 3, the adhesive layer (b1) is used as an adhesive layer (b) for laminating the transparent protective film (2) on the side of the aforementioned low elastic adhesive layer (a), and in FIG. 4, The adhesive layer (b2) is used as an adhesive layer (b) for laminating the transparent protective film (2) on the laminated side of the aforementioned low-elastic adhesive layer (a).

Respect to FIG. 3, FIG. 4 of the adhesive layer (b1), may also be adhesive layer (b1) used in the same manner of FIG. 2 at 85 ℃ storage elastic modulus of ^{1.0 × 10 6 ~ 1.0 × 10} 10 Pa, And the thickness satisfies 0.03 ~ 3μm. The storage elastic modulus of the adhesive layer (b1) at 25 ° C is preferably 5.0 × 10 ⁷ to 1.0 × 10 ¹⁰ Pa. The preferable ranges of the storage elastic modulus and the thickness of the adhesive layer (b1) are the same as those described in FIG. 2.

The adhesive layer (b2) of FIGS. 3 and 4 can use a storage elastic modulus of 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa at 85 ° C. and a thickness of 0.1 to 25 μm. The storage elastic modulus of the adhesive layer (b2) at 85 ° C is preferably 5.0 × 10 ⁴ to 5.0 × 10 ⁷ Pa, and more preferably 3.0 × 10 ⁵ to 1.0 × 10 ⁷ Pa. The thickness of the adhesive layer (b2) is preferably 0.5 to 15 μm, and more preferably 0.8 to 5 μm.

The storage elastic modulus of the adhesive layer (b2) at 25 ° C is 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa, preferably 5.0 × 10 ⁴ to 7.0 × 10 ⁷ Pa, and 1.0 × 10 ⁵ to 1.0 × 10 ⁷ Pa is more preferable.

Controlling the storage elastic modulus and thickness of the adhesive layers (b1) and (b2) within the aforementioned range is from the viewpoint of suppressing cracks in the polarizer during the thermal shock cycle test and further satisfying the impact resistance. good.

Furthermore, in the polarizing film (P) in the laminated polarizing film of FIG. 1B, a transparent protective film (2) is provided only on one side of the polarizer (1) by an adhesive layer (b). From the viewpoint of suppressing the expansion and contraction of the polarizer (1) and suppressing the occurrence of cracks (knick) when the polarizing film (P) is subjected to a heating test and a freeze cycle test, the polarizing film (P) of FIG. 1B In the adhesive layer (b), the aforementioned adhesive layer (b1) having a high elastic modulus is preferably used.

<Low elasticity adhesive layer (a)>

The low-elasticity adhesive layer (a) is a hardened material layer formed by solidification caused by the hardening of the low-elasticity adhesive. As the low-elasticity adhesive, a liquid composition capable of forming a hardened layer having a storage elastic modulus of 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa at 25 ° C. can be used. The low-elasticity adhesive is used to bond and integrate the surfaces of two adherends. When the two adherends are bonded, the aforementioned composition is coated on one or both of the two adherends and then adhered. Thereafter, the aforementioned composition is hardened by applying energy to form a warp. Solidified low elasticity adhesive layer (a).

As mentioned above, the storage elastic modulus of the low elastic adhesive layer (a) at 25 ° C is 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa. The formation of the low elastic adhesive layer (a) can satisfy the foregoing Adhesive for storing elastic modulus. As long as the low-elasticity adhesive layer (a) is optically transparent, various types of water-based, solvent-based, hot-melt, and active energy ray-curable types can be used without limitation.

For example, the low-elasticity adhesive layer (a) is preferably formed as a hardened material layer obtained by irradiating an active energy ray-curable adhesive with an active energy ray. As the active energy ray-curable adhesive, an electron beam-curable adhesive or an ultraviolet-curable adhesive can be used. The UV-curable adhesive can be roughly classified into a radical polymerization-curable adhesive and a cationic polymerization-type adhesive.

Examples of the curable component of the radical polymerization-curable adhesive include a compound having a (meth) acrylfluorenyl group and a radical polymerizable compound having a vinyl group. As these curable components, any of monofunctional or difunctional or more polyfunctional can be used. These curable components can be used alone or in combination of two or more. For example, the hardening component is preferably a compound having a (meth) acrylfluorenyl group.

Examples of the hardening component of the cation polymerization hardening type adhesive include compounds having an epoxy group, an oxo group, or a vinyl group. The compound having an epoxy group is not particularly limited as long as it has at least one epoxy group in the molecule, and various generally known curable epoxy compounds can be used. Preferred epoxy compounds include, for example, compounds having at least two epoxy groups and at least one aromatic ring in the molecule (hereinafter referred to as "aromatic epoxy compounds"), and having at least two epoxy groups in the molecule. And at least one of them is a compound or the like formed between two adjacent carbon atoms constituting an alicyclic ring.

The active energy ray-curable adhesive is not substantially used. Liquid matter containing organic solvents and viscosity 1 ~ 100cp / 25 ℃. By using such a liquid substance, a low-elasticity adhesive layer (a) having a thickness of 0.1 to 5 μm can be formed. The use of the liquid adhesive in the formation of the low-elasticity adhesive layer (a) is different from the point where the adhesive cloth used in the formation of the adhesive layer exhibits a liquid material. From this point of view, it is also obvious. It is known that the difference between the adhesive layer and the adhesive layer. The aforementioned viscosity is preferably 5 to 100 cp / 25 ° C, and more preferably 10 to 70 cp / 25 ° C. The “substantially free of organic solvent” means that the active energy ray-curable adhesive contains organic solvents in a range of 10% by weight or less with respect to the total amount of the active energy ray-curable adhesive. In addition, the content of the organic solvent is preferably 5% by weight or less, and more preferably 3% by weight or less. Here, the organic solvent refers to a liquid having an ignition point of 40 ° C or lower. The active energy ray-curable adhesive may not contain an organic solvent.

The active energy ray-curable adhesive is preferably one containing a radical polymerizable compound as a curable component. As the radical polymerizable compound, any of a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound (A) can be used. When the active energy ray hardening type adhesive is to make the total amount of the radical polymerizable compound 100% by weight, it is preferable that the polyfunctional radical polymerizable compound is contained in a proportion of more than 5% by weight and 50% by weight or less ( A) is better. As long as the low-elasticity adhesive layer (a) satisfies the aforementioned storage elastic modulus, the active energy ray-curable adhesive may contain other radical polymerizable compounds.

<Polyfunctional radical polymerizable compound (A)>

The polyfunctional radical polymerizable compound (A) is a compound having at least two radical polymerizable functional groups, and the radical polymerizable functional group has (A Group) Unsaturated double bonds such as acrylfluorenyl or vinyl. Examples of the polyfunctional radically polymerizable compound (A) include tetraethylene glycol diacrylate (Tg of a homopolymer: 50 ° C, hereinafter simply referred to as Tg), polyethylene glycol diacrylate, and polypropylene glycol diacrylate. Polyalkylene glycol-based diacrylates such as acrylate (n = 3, Tg at 69 ° C), (n = 7, Tg: -8 ° C), (n = 12, Tg: -32 ° C), neopentyl glycol di Acrylate (Tg: 117 ° C), 3-methyl-1,5-pentanediol diacrylate (Tg: 105 ° C), 1,6-hexanediol diacrylate (Tg: 63 ° C), 1,9-nonanediol diacrylate (Tg: 68 ° C), 2-methyl-1,8-octanediol diacrylate and 1,9-nonanediol diacrylate mixture (Tg: 88 ° C), dimethylol-tricyclodecane diacrylate (Tg: 75 ° C), bisphenol A EO adduct diacrylate (Tg: 75 ° C), bisphenol F EO modification (n = 2) Diacrylate (Tg: 75 ° C), bisphenol A EO modified (n = 2) diacrylate (Tg: 75 ° C), trimeric isocyanate EO modified diacrylate (Tg: 166 ° C) , Trimethylolpropane triacrylate (Tg: 250 ° C or higher), trimethylolpropane PO modified triacrylate (n = 1, Tg: 120 ° C), (n = 2, Tg: 50 ° C), Trimethylolpropane EO modified Triacrylate (n = 1, Tg not measured), (n = 2, Tg: 53 ° C), Trimeric isocyanate EO modified di and triacrylate (di: 30-40%, Tg: 250 ° C or more ), (Two: 3-13%, Tg: above 250 ° C), neopentyl alcohol three and four acrylates (three: 65-70%, Tg: above 250 ° C), (three: 55-63%, Tg : Above 250 ° C), (three: 40-60%, Tg: above 250 ° C), (three: 25-40%, Tg: above 250 ° C), (three: less than 10%, Tg: above 250 ° C), Ditrimethylolpropane tetraacrylate (Tg: 250 ° C or higher), dipentaerythritol penta- and hexaacrylate (five: 50-60%, Tg: 250 ° C or higher), (five: 40-50%, Tg: above 250 ° C), (Fri: 30-40%, Tg: above 250 ° C), (Fri: 25-35%, Tg: 250 ° C or higher), (Five: 10-20%, Tg: 250 ° C or higher), and corresponding (meth) acrylates. Examples include other various oligomers (meth) acrylates such as polyurethane (meth) acrylate, polyester (meth) acrylate, and polyepoxy (meth) acrylate. In addition, as the polyfunctional radical polymerizable compound (A), a commercially available product can also be suitably used, and examples thereof include Light Acrylate 4EG-A, Light Acrylate 9EG-A, Light Acrylate NP-A, Light Acrylate MPD-A, Light Acrylate 1.6HX-A, Light Acrylate 1.9ND-A, Light Acrylate MOD-A, Light Acrylate DCP-A, Light Acrylate BP-4EAL or higher (manufactured by Kyoeisha Chemical Co., Ltd.), Aronix M-208, M-211B, M-215, M-220, M-225, M-270, M-240, M-309, M-310, M-321, M-350, M-360, M-313, M-315, M- 306, M-305, M-303, M-452, M-450, M-408, M-403, M-400, M-402, M-404, M-406, M-405, M-1100, M-1200, M-6100, M-6200, M-6250, M-6500, M-7100, M-7300, M-8030, M-8060, M-8100, M-8530, M-8560, M- 9050 (manufactured by Toa Synthetic Corporation), SR-531 (manufactured by SARTOMER), CD-536 (manufactured by SARTOMER), etc. The polyfunctional radically polymerizable compound (A) is preferably one in which the Tg of the homopolymer satisfies -40 to 100 ° C.

The polyfunctional radically polymerizable compound (A) is more preferably one having a longer distance between crosslinking points. By making the distance between the crosslinking points longer, the amount of deformation of the main body of the low-elasticity adhesive layer (a) can be increased, and a laminated polarizing film having particularly excellent impact resistance can be obtained. The functional radical polymerizable compound (A) having a much longer distance between crosslinking points is preferably a bifunctional (meth) acrylate having two (meth) acrylfluorenyl groups. The weight average molecular weight of bifunctional (meth) acrylate is based on 200 ~ 4000 is better, 400 ~ 2000 is better, and 500 ~ 1000 is best. When the weight average molecular weight is too large, the viscosity of the active energy ray-curable adhesive will become high, and there will be a tendency that the coating thickness becomes non-uniform to cause appearance defects, or that bubbles may enter during the adhesion step to cause appearance defects. From the foregoing viewpoint, the bifunctional (meth) acrylate is preferably a linear structure. Furthermore, the distance between the crosslinking points of a trifunctional (meth) acrylate having three or more (meth) acrylfluorenyl groups is shorter than that of a bifunctional (meth) acrylate. From the viewpoint of the effect (impact resistance) of the present invention, a bifunctional (meth) acrylate is preferred.

Examples of the bifunctional (meth) acrylate having a weight average molecular weight of 200 to 4000 include polyalkylene glycols such as polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate. Di (meth) acrylates, polyester (meth) acrylates, polyurethane (meth) acrylates, oligomers (meth) acrylates such as poly (epoxy) methacrylates Wait.

When the total amount of the radically polymerizable compound in the active energy ray-curable adhesive is 100% by weight, the proportion of the polyfunctional radically polymerizable compound (A) is preferably 1 to 65% by weight. When the aforementioned ratio is set to 1% by weight or more, it is preferable because the impact resistance, thermal buckling resistance, and cracks of the polarizer can be satisfied for the low-elasticity adhesive layer (a).

As said polyfunctional radical polymerizable compound (A), the said bifunctional (meth) acrylate whose weight average molecular weight is 200-4000 can be used as all or a part. When the total amount of the radical polymerizable compound in the active energy ray-curable adhesive is 100% by weight, the proportion of the bifunctional (meth) acrylate having a weight average molecular weight of 200 to 4000 is 1 to 65% by weight. It is better, more preferably 2 to 50% by weight, and most preferably 3 to 20% by weight. When the foregoing ratio is high, the amount of deformation of the main body of the low-elasticity adhesive layer (a) becomes smaller, the peeling force becomes smaller, and the impact resistance tends to decrease.

<Alkyl (meth) acrylate (B) having an alkyl group having 2 to 18 carbon atoms>

The active energy ray hardening type adhesive used in the formation of the aforementioned low-elasticity adhesive layer (a) may contain an alkyl (meth) acrylate (B) having an alkyl group having 2 to 18 carbons as a free Monofunctional radical polymerizable compound based on a polymerizable compound. Examples of the alkyl (meth) acrylate (B) include those having 1 to 18 carbon atoms in the linear or branched alkyl group. For example, the aforementioned alkyl group can be exemplified by: methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, pentyl, hexyl, cyclohexyl, heptyl, 2-ethylhexyl, iso Octyl, nonyl, decyl, isodecyl, dodecyl, isotetradecyl, lauryl, tridecyl, pentadecyl, hexadecyl, heptyl, stearyl, isostearyl, etc. . They can be used alone or in combination. The alkyl (meth) acrylate (B) is preferably one having an alkyl carbon number of 3 to 18. From the standpoint of durability and water resistance to peeling in a drop test, the alkyl (meth) acrylate (B) is preferably one in which the Tg of the homopolymer satisfies -80 to 60 ° C. For example, methyl acrylate (Tg: 8 ° C), ethyl acrylate (Tg: -20 ° C), n-propyl acrylate (Tg: 8 ° C), n-butyl acrylate (Tg: -45 ° C) can be suitably used. ), Isobutyl acrylate (Tg: -26 ° C), third butyl acrylate (Tg: 14 ° C), isoamyl acrylate (Tg: -45 ° C), cyclohexyl acrylate (Tg: 8 ° C), acrylic acid 2-ethylhexyl (Tg: -55 ° C), n-octyl acrylate (Tg: -65 ° C), isooctyl acrylate (Tg: -58 ° C), isononyl acrylate (Tg: -58 ° C), Lauryl acrylate (Tg: 15 ° C), propylene Alkyl acrylates such as stearyl acid (Tg: 30 ° C) and isostearyl acrylate (Tg: -18 ° C).

From the viewpoint of satisfying impact resistance and thermal buckling resistance, the proportion of the alkyl (meth) acrylate (B) is such that the total amount of radical polymerizable compounds in the active energy ray-curable adhesive is 100 weight In the case of%, it is preferably used at a ratio of 60% by weight or less. The foregoing ratio is preferably 10 to 50% by weight, and more preferably 20 to 40% by weight.

<(Meth) acrylate (C) having a hydroxyl group>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may contain a (meth) acrylate (C) having a hydroxyl group as a monofunctional radical of a radical polymerizable compound Polymerizable compound. As the (meth) acrylate (C) having a hydroxyl group, those having a (meth) acrylfluorenyl group and a hydroxyl group can be used. Specific examples of the (meth) acrylate (C) having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (methyl) Acrylate), 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate Hydroxyalkyl (meth) acrylates having 2 to 12 carbon atoms in alkyl groups such as esters or (4-hydroxymethylcyclohexyl) -methacrylates. From the viewpoint of durability against peeling in a drop test, the (meth) acrylate (C) having a hydroxyl group is preferably one in which the Tg of the homopolymer satisfies -80 to 40 ° C. For example, hydroxyethyl acrylate (Tg: -15 ° C), hydroxypropyl acrylate (Tg: -7 ° C), hydroxybutyl acrylate (Tg: -32 ° C), and the like are preferably used.

The (meth) acrylate (C) having a hydroxyl group may be a hydroxyl group. Longer chain length with (meth) acrylfluorenyl. By making the chain length between the hydroxyl group and the (meth) acrylfluorenyl group longer, it becomes easier to align the hydroxyl group to the adhered film, and the adhesiveness derived from the hydroxyl polarity can be made more effective. It is better to proceed from the viewpoint of ground. The (meth) acrylic acid ester (C) having a hydroxyl group and a long chain length between the hydroxyl group and the (meth) acrylfluorenyl group is a hydroxyl-containing monofunctional (formaldehyde) with a weight average molecular weight of 160 to 3000 Base) acrylate is preferred. The weight average molecular weight of the aforementioned hydroxyl-containing monofunctional (meth) acrylate is more preferably 200 to 2000, and most preferably 300 to 1,000. As for the hydroxyl-containing monofunctional (meth) acrylate having a weight average molecular weight of 160 to 3000, it is preferable that the chain length between the hydroxyl group and the (meth) acrylfluorenyl group is long, and the hydroxyl group and the (meth) group are preferred. Acrylofluorenyl is preferably located at both ends (especially in a linear structure).

When the weight average molecular weight of the (meth) acrylate (C) having a hydroxyl group is too large, the viscosity of the active energy ray-curable adhesive becomes high, the coating thickness becomes uneven, and appearance defects occur, or It is not good to have appearance defects due to air bubbles entering in the bonding step. Moreover, since the number of hydroxyl groups is relatively decreased, it is difficult to obtain the effect of imparting adhesiveness derived from the polarity of the hydroxyl groups, which is not preferable. Examples of the hydroxyl-containing monofunctional (meth) acrylate having a weight-average molecular weight of 160 to 3000 include those having a weight-average molecular weight of 160 to 3000 in the aforementioned hydroxyalkyl (meth) acrylates, and polyethylene glycol mono (methyl) ) Polyalkylene glycol mono (meth) acrylates such as acrylic esters, polypropylene glycol mono (meth) acrylates, polyethylene glycols, polypropylene glycol mono (meth) acrylates, and the aforementioned hydroxyalkyl (meth) groups Modified products of acrylate or (4-hydroxymethylcyclohexyl) -methacrylate caprolactone and the like. The caprolactone modified system can suitably use hydroxy Caprolactone adducts of ethyl (meth) acrylate, and the addition amount of caprolactone is preferably 1 to 5 moles.

From the viewpoint of satisfying impact resistance and thermal buckling resistance, the ratio of the (meth) acrylic acid ester (C) having a hydroxyl group makes the total amount of radical polymerizable compounds in the active energy ray-curable adhesive to 100 In the case of% by weight, it is preferably used at a ratio of 70% by weight or less. When the foregoing ratio is high, the influence of the hydrophilicity of the hydroxyl group becomes large, and the water resistance such as peeling in a humidified environment is deteriorated, which is not preferable. When using a hydroxyalkyl (meth) acrylate, (4-hydroxymethylcyclohexyl) -methacrylate, etc., the aforementioned ratio of the (meth) acrylate (C) having a hydroxyl group is 10 to 60 weight % Is better, and more preferably 20 to 50% by weight. When a hydroxyl-containing monofunctional (meth) acrylate having a weight average molecular weight of 160 to 3000 is used, and when the total amount of the radical polymerizable compound in the active energy ray-curable adhesive is 100% by weight, The (meth) acrylate (C) having a hydroxyl group is preferably 1 to 70% by weight, and more preferably 30 to 60% by weight.

<Measurement of weight average molecular weight>

The weight average molecular weight of the aforementioned bifunctional (meth) acrylate and hydroxyl-containing monofunctional (meth) acrylate can be measured by GPC (gel chromatography).

‧Detector: Differential Refractometer (RI)

‧Standard sample: polystyrene

<Other radical polymerizable compounds>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may contain a radical polymerizable compound other than the foregoing as a radical polymerizable compound. From the adhesive layer From the viewpoint that the balance of properties, durability, and water resistance is improved with a better balance, other radical polymerizable compounds are preferably those having a polar group. Examples of the monofunctional radically polymerizable compound of other radically polymerizable compounds include hydroxyethyl acrylamide, N-methylol acrylamide, acryl amidinoline, N-methoxymethacrylamide, N-ethoxymethacrylamide, N-vinylcaprolactam and the like.

From the viewpoints of adhesiveness, durability, and water resistance of the adhesive layer, when the proportion of other radically polymerizable compounds is 100% by weight of the total amount of radically polymerizable compounds in the active energy ray-curable adhesive. It is preferably used at a ratio of 30% by weight or less. The foregoing ratio is preferably 2 to 25% by weight, and more preferably 5 to 20% by weight.

<Polysilane-free coupling agent (D)>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may contain a silane coupling agent (D) in addition to the radical polymerizable compound. The silane coupling agent (D) is preferably a silane coupling agent having no radical polymerizable functional group. Silane coupling agents which do not have a radical polymerizable functional group can act on the surface of a polarizer and provide further water resistance.

Specific examples of the silane coupling agent having no radical polymerizable functional group include a silane coupling agent having an amine group. Specific examples of the silane coupling agent having an amine group include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, γ- Aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-amine Ethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2-amine Ethyl) aminopropylmethyldiethoxysilane, γ- (2-aminoethyl) aminopropyltriisopropoxysilane, γ- (2- (2-aminoethyl) amine Ethyl) aminopropyltrimethoxysilane, γ- (6-aminohexyl) aminopropyltrimethoxysilane, 3- (N-ethylamino) -2-methylpropyltrimethoxy Silane, γ-ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-amine Propyltrimethoxysilane, N-vinylbenzyl-γ-aminopropyltriethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-cyclohexylaminomethyldiethyl Oxymethylsilane, N-phenylaminomethyltrimethoxysilane, (2-aminoethyl) aminomethyltrimethoxysilane, N, N'-bis [3- (trimethoxysilyl) propane Group] amines containing silanes such as ethylenediamine; ketimine-type silanes such as N- (1,3-dimethylbutylene) -3- (triethoxysilyl) -1-propaneamine.

The silane coupling agent having an amine group is preferably one of the following: γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-amine Ethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropylmethyl Diethoxysilane, N- (1,3-dimethylbutylene) -3- (triethoxysilyl) -1-propaneamine.

Specific examples of the silane coupling agent which does not have a radical polymerizable functional group other than the silane coupling agent having an amine group include 3-chloropropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxy Silyl, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatepropyltriethoxysilane, imidazolesilane, and the like.

Examples of the silane coupling agent (D) include vinyltrichlorosilane, Vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-epoxy Propoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxy Silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-propenyloxypropyltrimethoxysilane and the like are used as active energy ray hardening compounds.

The silane coupling agent (D) may be used singly or in combination. The blending amount of the silane coupling agent (D) having no radical polymerizable functional group is usually 20 parts by weight or less based on 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. The range of 0.01 to 20 parts by weight is preferred, and 0.05 to 15 parts by weight is more preferred, and 0.1 to 10 parts by weight is even more preferred. When the blending amount is more than 20 parts by weight, the storage stability of the adhesive may be deteriorated.

<Acrylic oligomer (E) obtained by polymerizing (meth) acrylic monomer>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may contain, in addition to the radically polymerizable compound, an acrylic polymer obtained by polymerizing a (meth) acrylic monomer. Oligomeric (E). By containing the acrylic oligomer (E) in the active energy ray hardening type adhesive, the curing shrinkage when the composition is irradiated with the active energy ray and hardened can be reduced, and the adhesive and the polarizing film ( P) and the interfacial stress of the adherend such as the optical film (3). As a result, the adhesion between the adhesive layer and the adherend can be suppressed. Reduction in sexuality.

When considering workability and uniformity during coating, the active energy ray-curable adhesive has a low viscosity, so the acrylic oligomer (E) obtained by polymerizing a (meth) acrylic monomer is also Low viscosity is better. The acrylic oligomer having a low viscosity and preventing hardening and shrinkage of the adhesive layer is preferably a weight average molecular weight (Mw) of 15,000 or less, more preferably 10,000 or less, and particularly preferably 5,000 or less. On the other hand, in order to sufficiently suppress the hardening shrinkage of the hardened material layer (adhesive layer), the weight average molecular weight (Mw) of the acrylic oligomer (E) is preferably 500 or more, and more preferably 1,000 or more. Above 1500 is especially good. Specific examples of the (meth) acrylic monomer constituting the acrylic oligomer (E) include meth (meth) acrylate, ethyl (meth) acrylate, and n-propyl (meth) acrylic acid. Ester, isopropyl (meth) acrylate, 2-methyl-2-nitropropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, Second butyl (meth) acrylate, third butyl (meth) acrylate, n-pentyl (meth) acrylate, third pentyl (meth) acrylate, 3-pentyl (methyl ) Acrylate, 2,2-dimethylbutyl (meth) acrylate, n-hexyl (meth) acrylate, cetyl (meth) acrylate, n-octyl (meth) acrylate, 2 (Ethyl) hexyl (meth) acrylate, 4-methyl-2-propylpentyl (meth) acrylate, N-octadecyl (meth) acrylate, etc. 1-20) Alkyl esters, for example: cycloalkyl (meth) acrylates (such as cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, etc.), aralkyl (methyl) Acrylates (e.g. benzyl (meth) acrylate, etc.), polycyclic (meth) acrylates (e.g., 2-iso (Meth) acrylate, 2-nor Methyl (meth) acrylate, 5-norbornene-2-yl-methyl (meth) acrylate, 3-methyl-2-nor Methyl (meth) acrylate, etc.), hydroxyl-containing (meth) acrylates (e.g., hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2,3- Dihydroxypropylmethyl-butyl (meth) methacrylate, etc.), (meth) acrylates containing alkoxy or phenoxy (2-methoxyethyl (meth) acrylate , 2-ethoxyethyl (meth) acrylate, 2-methoxymethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethylcarbitol (Meth) acrylates, phenoxyethyl (meth) acrylates, etc.), epoxy-containing (meth) acrylates (e.g., dehydroglyceryl (meth) acrylates, etc.), halogen-containing (Meth) acrylates (e.g. 2,2,2-trifluoroethyl (meth) acrylate, 2,2,2-trifluoroethylethyl (meth) acrylate, tetrafluoropropyl ( (Meth) acrylate, hexafluoropropyl (meth) acrylate, octafluoropentyl (meth) acrylate, heptafluorodecyl (meth) acrylate, etc.), alkylaminoalkyl (methyl Acrylate) (such as dimethylaminoethyl (meth) acrylate, etc.). These (meth) acrylates can be used alone or in combination of two or more kinds. Specific examples of the acrylic oligomer (E) include "ARUFON" manufactured by Toa Kasei Corporation, "Act Flow" manufactured by Kenken Chemical Co., and "JONCRYL" manufactured by BASF Japan.

The blending amount of the acrylic oligomer (E) is usually preferably 30 parts by weight or less based on 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. When the content of the acrylic oligomer (E) in the composition is too large, the reaction rate when the composition is irradiated with active energy rays may be drastically reduced, and the curing may become poor. On the other hand, in order to sufficiently suppress the hardening shrinkage of the hardened material layer (adhesive layer a), the composition preferably contains 3 parts by weight or more of the acrylic oligomer (E), and contains 5 More preferably, it is by weight or more.

<Free radical polymerizable compound (F) having a living methylene group and a radical polymerization initiator (G) having a hydrogen abstraction effect>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may further contain a radical polymerizable compound (F) having an active methylene group in addition to the radical polymerizable compound. And a radical polymerization initiator (G) having a hydrogen abstraction effect. With such a structure, the adhesiveness of the low-elasticity adhesive layer (a) can be significantly improved even after being taken out from a high-humidity environment or water (non-drying state). Although the reason is not clear, it is considered to be the following reason. In other words, the radically polymerizable compound (F) having an active methylene group is polymerized with other radically polymerizable compounds constituting the low-elasticity adhesive layer (a), and the low-elasticity adhesive layer (a) is incorporated. The main chain and / or side chain of the intermediate base polymer form a low-elasticity adhesive layer (a). In such a polymerization process, if a radical polymerization initiator (G) having a hydrogen abstraction effect is present, a base polymer constituting a low-elasticity adhesive layer (a) is formed, and at the same time, active methylene The radically polymerizable compound (F) of a radical robs hydrogen and generates a radical in a methylene group. As a result, the methylene group having generated radicals reacts with the hydroxyl group of a polarizer such as PVA, and a covalent bond is formed between the low-elasticity adhesive layer (a) and the polarizer (1). As a result, it is estimated that the adhesiveness of the adhesive layer which a polarizing film has, especially in the non-drying state, can be significantly improved.

The radically polymerizable compound (F) having an active methylene group is a compound having an active double bond group such as a (meth) propenyl group in a terminal or a molecule and having an active methylene group. Examples of active methylene groups include: Alkoxypropylenediyl, cyanoethylfluorenyl, and the like. Specific examples of the radically polymerizable compound (F) having an active methylene group include, for example, 2-acetamethyleneacetoxyethyl (meth) acrylate, 2-acetamethyleneacetoxypropyl (methyl) ) Acrylate, 2-Ethylacetoxy-1-methylethyl (meth) acrylate, etc. Ethylacetoxyalkyl (meth) acrylate; 2-ethoxypropanefluorene Oxyethyl (meth) acrylate, 2-cyanoacetamidooxyethyl (meth) acrylate, N- (2-cyanoacetamidooxyethyl) acrylamidonium, N- (2 -Propanyloxyethoxybutyl) acrylamidonium, N- (4-Ethylacetoxymethylbenzyl) acrylamidonium, N- (2-Ethylacetaminoethylethyl) ethyl Group) acrylamide and the like.

Examples of the radical polymerization initiator (G) having a hydrogen abstraction function are: 9-oxysulfur Based radical polymerization initiator, benzophenone based radical polymerization initiator, and the like. 9-oxysulfur Examples of the radical polymerization initiator include compounds represented by the following general formula (1):

(Wherein R ¹ and R ² represent -H, -CH _2b H ₃ , -iPr or Cl, and R ¹ and R ² may be the same or different).

Specific examples of the compound represented by the general formula (1) include, for example, 9-oxysulfur Dimethyl 9-oxysulfur Diethyl 9-oxysulfur Isopropyl 9-oxysulfur Chlorine 9-oxysulfur Wait. Among the compounds represented by the general formula (1), R ¹ and R ² are diethyl 9-oxysulfur of -CH _2b H ₃ Extraordinary.

In addition, the active energy ray-curable adhesive is preferably a compound represented by the following general formula (2) as a photopolymerization initiator in addition to the photopolymerization initiator of the general formula (1);

(Wherein R ³ , R ⁴ and R ⁵ represent -H, -CH _3b H _2b H ₃ , -iPr or Cl, and R ³ , R ⁴ and R ⁵ may be the same or different). By using the photopolymerization initiators of the general formula (1) and the general formula (2) in combination, it is possible to increase the efficiency of the reaction due to such photosensitizing reactions, and to particularly improve the adhesiveness of the adhesive layer.

As described above, in the present invention, in the presence of a radical polymerization initiator (G) having a hydrogen abstraction effect, the methylene group of the radically polymerizable compound (F) having a living methylene group is generated. Free radicals and react such methylene groups with hydroxyl groups to form covalent bonds. Therefore, in order to sufficiently generate such a covalent bond in order to generate radicals on the methylene group of the radically polymerizable compound (F) having an active methylene group, the radically polymerizable polymer in the active energy ray-curable adhesive is formed. When the total amount of the compound is 100 parts by weight, it has active methylene The radical polymerizable compound (F) is preferably contained in an amount of 1 to 30 parts by weight, and more preferably contained in an amount of 3 to 30 parts by weight. If the radically polymerizable compound (F) having an active methylene group is less than 1 part by weight, the adhesion improvement effect in a non-dried state may be low, and the water resistance may not be sufficiently improved; or more than 50 Part by weight may cause poor curing of the adhesive layer. In addition, the radical polymerization initiator (G) having a hydrogen abstraction function is preferably contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. It is more preferably 0.3 to 9 parts by weight. When the radical polymerization initiator (G) having a hydrogen abstraction effect is less than 0.1 part by weight, the hydrogen abstraction reaction may not be sufficiently performed; or when it exceeds 10 parts by weight, it may not be completely dissolved in the composition.

<Photoacid generator (H)>

The active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) may further contain a photoacid generator (H) in addition to the radical polymerizable compound. When the photo-acid generator is contained in the active energy ray-curable resin composition, the water resistance and durability of the adhesive layer can be dramatically improved compared to the case where the photo-acid generator is not contained. The photoacid generator (H) can be represented by the following general formula (3).

Formula (3)

[3] of L ⁺ X ^-

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

Preferred onium cation structures constituting the onium cation L ⁺ of the general formula (3) include onium cations selected from the following general formulas (4) to (12).

Formula (4)

General formula (5)

Formula (6)

[Chemical 6]

General formula (7)

Formula (8)

Formula (9)

[Chemical 9]

Formula (10)

Formula (11)

Formula (12)

[Chemical 12] (However, in the aforementioned general formulae (4) to (12), R ¹ , R ² and R ³ each independently represent a group selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or Unsubstituted alkenyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, A substituted or unsubstituted heterocyclooxy group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbonyloxy group, a substituted or unsubstituted oxycarbonyl group or a halogen atom. R ⁴ represents The same groups as those described in R ¹ , R ² and R ^3. R ⁵ represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylthio group, and R ⁶ and R ⁷ are independent of each other. Represents: substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy. R represents any of the following: halogen atom, hydroxyl, carboxyl, mercapto, cyano, nitro, substituted or unsubstituted Substituted carbamoyl, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted aryl, Substituted or unsubstituted heterocyclyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted heterocyclooxy, substituted or unsubstituted Alkylthio, substituted or unsubstituted arylthio, substituted or unsubstituted heterocyclicthio, substituted or unsubstituted fluorenyl, substituted or unsubstituted carbonyloxy, A substituted or unsubstituted oxycarbonyl group. Ar ⁴ and Ar ⁵ represent any of the following: a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group. X represents an oxygen or sulfur atom. i represents an integer from 0 to 5. j represents an integer from 0 to 4. k represents an integer from 0 to 3. Further, between adjacent Rs, Ar ⁴ and Ar ⁵ , R ² and R ³ , and R ² and R. ^4. R ³ and R ⁴ , R ¹ and R ² , R ¹ and R ³ , R ¹ and R ⁴ , R ¹ and R, or R ¹ and R ⁵ may also be a cyclic structure formed by bonding to each other.)

Corresponding to an onium cation (fluorene cation) of the general formula (4): Although the following can be listed, they are not limited to the following: dimethylphenylphosphonium, dimethyl (o-fluorophenyl) phosphonium, dimethyl (M-chlorophenyl) fluorene, dimethyl (p-bromophenyl) fluorene, dimethyl (p-cyanophenyl) fluorene, dimethyl (m-nitrophenyl) fluorene, dimethyl (2,4 , 6-tribromophenyl) fluorene, dimethyl (pentafluorophenyl) fluorene, dimethyl (p- (trifluoromethyl) phenyl) fluorene, dimethyl (p-hydroxyphenyl) fluorene, dimethyl (P-mercaptophenyl) fluorene, dimethyl (p-methylsulfinylphenyl) fluorene, dimethyl (p-methylsulfonylphenyl) fluorene, dimethyl (o-ethylfluorenylphenyl) Hydrazone, dimethyl (o-benzoylphenyl) phenyl, dimethyl (p-methylphenyl) fluorene, dimethyl (p-isopropylphenyl) fluorene, dimethyl (p-octadecylbenzene) Yl) fluorene, dimethyl (p-cyclohexylphenyl) fluorene, dimethyl (p-methoxyphenyl) fluorene, dimethyl (o-methoxycarbonylphenyl) fluorene, dimethyl (p-phenylyl) Sulfanylphenyl) fluorene, (7-methoxy-2- pendantoxy-2H-benzopiperan-4-yl) dimethylfluorene, (4-methoxynaphthalene-1-yl) di Methylfluorene, dimethyl (p-isopropoxycarbonylphenyl) fluorene, dimethyl ( 2-naphthyl) fluorene, dimethyl (9-anthryl) fluorene, diethylphenylfluorene, methylethylphenylfluorene, methyldiphenylfluorene, triphenylfluorene, diisopropylbenzene Hydrazone, diphenyl (4-phenylsulfanyl-phenyl) -fluorene, 4,4'-bis (diphenylfluorene) diphenylsulfide, 4,4'-bis [bis [(4- (2-hydroxy-ethoxy) -phenyl)] 鋶]] diphenyl sulfide, 4,4'-bis (diphenyl 鋶) biphenyl, diphenyl (o-fluorophenyl) 鋶, Diphenyl (m-chlorophenyl) fluorene, diphenyl (p-bromophenyl) fluorene, diphenyl (p-cyanophenyl) fluorene, diphenyl (m-nitrophenyl) fluorene, diphenyl ( 2,4,6-tribromophenyl) fluorene, diphenyl (pentafluorophenyl) fluorene, di Phenyl (p- (trifluoromethyl) phenyl) fluorene, diphenyl (p-hydroxyphenyl) fluorene, diphenyl (p-mercaptophenyl) fluorene, diphenyl (p-methylfluorenylenephenyl) Hydrazone, diphenyl (p-methylsulfonylphenyl) hydrazone, diphenyl (o-ethylfluorenylphenyl) hydrazone, diphenyl (o-benzylfluorenylphenyl) hydrazone, diphenyl (p-methyl Phenyl) fluorene, diphenyl (p-isopropylphenyl) fluorene, diphenyl (p-octadecylphenyl) fluorene, diphenyl (p-cyclohexylphenyl) fluorene, diphenyl (p-methyl Oxyphenyl) fluorene, diphenyl (o-methoxycarbonylphenyl) fluorene, diphenyl (p-phenylsulfanylphenyl) fluorene, (7-methoxy-2- pendantoxy-2H -Benzopiperan-4-yl) diphenylphosphonium, (4-methoxynaphthalen-1-yl) diphenylphosphonium, diphenyl (p-isopropoxycarbonylphenyl) phosphonium, diphenyl (2-naphthyl) fluorene, diphenyl (9-anthryl) fluorene, ethyldiphenylfluorene, methylethyl (o-tolyl) fluorene, methylbis (p-tolyl) fluorene, tris (p-tolyl) fluorene Tolyl) fluorene, diisopropyl (4-phenylsulfanylphenyl) fluorene, diphenyl (2-thienyl) fluorene, diphenyl (2-furyl) fluorene, diphenyl (9- Ethyl-9Hcarbazol-3-yl) fluorene and the like.

Corresponding to an onium cation (phosphonium cation) of the general formula (5): Although the following may be mentioned, they are not limited to the following: dimethylphenylphosphonium, dimethyl (o-fluorophenyl) Phosphonium, dimethyl (m-chlorophenyl) phosphonium, dimethyl (p-bromophenyl) phosphonium, dimethyl (p-cyanophenyl) phosphonium, dimethyl (m-nitro) Phenyl) phosphonium, dimethyl (2,4,6-tribromophenyl) phosphonium, dimethyl (pentafluorophenyl) phosphonium, dimethyl (p- (trifluoromethyl) Phenyl) phosphonium, dimethyl (p-hydroxyphenyl) phosphonium, dimethyl (p-mercaptophenyl) phosphonium, dimethyl (p-methyl phenylene) phosphonium, Dimethyl (p-methylsulfonylphenyl) phosphonium, dimethyl (o-ethylfluorenylphenyl) phosphonium, dimethyl (o-benzoylphenyl) phosphonium, dimethyl (P-methylphenyl) phosphonium, dimethyl (p-isopropylphenyl) phosphonium, dimethyl (p-octadecylphenyl) Phosphonium, dimethyl (p-cyclohexylphenyl) phosphonium, dimethyl (p-methoxyphenyl) phosphonium, dimethyl (o-methoxycarbonylphenyl) phosphonium, di Methyl (p-phenylsulfanylphenyl) sulfenium, (7-methoxy-2- pendantoxy-2H-benzopiperan-4-yl) dimethylphosphonium, (4- Methoxynaphthalen-1-yl) dimethylphosphonium, dimethyl (p-isopropoxycarbonylphenyl) phosphonium, dimethyl (2-naphthyl) phosphonium, dimethyl ( 9-Anthracenyl) phosphonium, diethylphenylphosphonium, methylethylphenylphosphonium, methyldiphenylphosphonium, triphenylphosphonium, diisopropylphenyl Phosphonium, diphenyl (4-phenylsulfanyl-phenyl) -phosphonium, 4,4'-bis (diphenylphosphonium) diphenylsulfide, 4,4'-bis [ Di [(4- (2-hydroxy-ethoxy) -phenyl)] phosphonium] diphenylsulfide, 4,4'-bis (diphenylphosphonium) phenylene, diphenyl (O-fluorophenyl) phosphonium, diphenyl (m-chlorophenyl) phosphonium, diphenyl (p-bromophenyl) phosphonium, diphenyl (p-cyanophenyl) phosphonium, Diphenyl (m-nitrophenyl) phosphonium, diphenyl (2,4,6-tribromophenyl) phosphonium, diphenyl (pentafluorophenyl) ) Phosphonium, diphenyl (p- (trifluoromethyl) phenyl) phosphonium, diphenyl (p-hydroxyphenyl) phosphonium, diphenyl (p-mercaptophenyl) phosphonium, di Phenyl (p-methylsulfenylphenyl) phosphonium, diphenyl (p-methylsulfonylphenyl) phosphonium, diphenyl (o-ethylfluorenyl) phosphonium, diphenyl (O-benzoyl phenyl) phosphonium, diphenyl (p-methylphenyl) phosphonium, diphenyl (p-isopropylphenyl) phosphonium, diphenyl (p-octadecyl Phenyl) phosphonium, diphenyl (p-cyclohexylphenyl) phosphonium, diphenyl (p-methoxyphenyl) phosphonium, diphenyl (o-methoxycarbonylphenyl) Phosphonium, diphenyl (p-phenylsulfanylphenyl) sulfenium, (7-methoxy-2- pendantoxy-2H-benzopiperan-4-yl) diphenylphosphonium (4-methoxynaphthalene-1-yl) diphenylphosphonium, diphenyl (p-isopropoxycarbonylphenyl) phosphonium, diphenyl (2-naphthalene (Ylidene) phosphonium, diphenyl (9-anthryl) phosphonium, ethyldiphenylphosphonium, methylethyl (o-tolyl) phosphonium, methylbis (p-tolyl) Phosphonium, tri (p-tolyl) phosphonium, diisopropyl (4-phenylsulfanylphenyl) phosphonium, diphenyl (2-thienyl) phosphonium, diphenyl (2 -Furyl) phosphonium, diphenyl (9-ethyl-9Hcarbazol-3-yl) phosphonium and the like.

Corresponding to onium cations (fluorene cations) of general formula (6): Examples of sulfonium cations: Although the following can be listed, they are not limited to the following: trimethylphenylphosphonium, triethylphenylphosphonium, tetrabenzene Hydrazone, triphenyl (p-fluorophenyl) fluorene, triphenyl (o-chlorophenyl) fluorene, triphenyl (m-bromophenyl) fluorene, triphenyl (p-cyanophenyl) fluorene, triphenyl (M-nitrophenyl) fluorene, triphenyl (p-phenylsulfanylphenyl) fluorene, (7-methoxy-2- pendantoxy-2H-benzopiperan-4-yl) tri Phenylfluorene, triphenyl (o-hydroxyphenyl) fluorene, triphenyl (o-ethylfluorenylphenyl) fluorene, triphenyl (m-benzoylfluorenylphenyl) fluorene, triphenyl (p-methylbenzene ) Fluorene, triphenyl (p-isopropoxyphenyl) fluorene, triphenyl (o-methoxycarbonylphenyl) fluorene, triphenyl (1-naphthyl) fluorene, triphenyl (9-anthracene) Group), triphenyl (2-thienyl) fluorene, triphenyl (2-furanyl) fluorene, triphenyl (9-ethyl-9Hcarbazol-3-yl) fluorene, and the like.

Corresponding to onium cations (pyridinium cations) of the general formula (7): Examples of pyridinium cations: Although the following can be listed, they are not limited to the following: N-phenylpyridinium, N- (o-chlorophenyl) ) Pyridinium, N- (m-chlorophenyl) pyridinium, N- (p-cyanophenyl) pyridinium, N- (o-nitrophenyl) pyridinium, N- (p-ethylfluorenylphenyl) pyridine Onium, N- (p-isopropylphenyl) pyridinium, N- (p-octadecyloxyphenyl) pyridinium, N- (p-methoxycarbonylphenyl) pyridinium, N- (9-anthracene ) Pyridine Onium, 2-chloro-1-phenylpyridinium, 2-cyano-1-phenylpyridinium, 2-methyl-1-phenylpyridinium, 2-vinyl-1-phenylpyridinium, 2 -Phenyl-1-phenylpyridinium, 1,2-diphenylpyridinium, 2-methoxy-1-phenylpyridinium, 2-phenoxy-1-phenylpyridinium, 2-ethyl Fluorenyl-1- (p-tolyl) pyridinium, 2-methoxycarbonyl-1- (p-tolyl) pyridinium, 3-fluoro-1-naphthylpyridinium, 4-methyl-1- (2 -Furyl) pyridinium, N-methylpyridinium, N-ethylpyridinium, and the like.

Corresponding to onium cations (quinolinium cations) of the general formula (8): Examples of quinolinium cations: Although the following can be listed, they are not limited to the following: N-methylquinolinium, N-ethyl Quinolinium, N-phenylquinolinium, N-naphthylquinolinium, N- (o-chlorophenyl) quinolinium, N- (m-chlorophenyl) quinolinium, N- (p-cyano) Phenyl) quinolinium, N- (o-nitrophenyl) quinolinium, N- (p-ethylfluorenyl) quinolinium, N- (p-isopropylphenyl) quinolinium, N- (P-octadecyloxyphenyl) quinolinium, N- (p-methoxycarbonylphenyl) quinolinium, N- (9-anthryl) quinolinium, 2-chloro-1-phenylquine Porphyrinium, 2-cyano-1-phenylquinolinium, 2-methyl-1-phenylquinolinium, 2-vinyl-1-phenylquinolinium, 2-phenyl-1-benzene Quinolinium, 1,2-diphenylquinolinium, 2-methoxy-1-phenylquinolinium, 2-phenoxy-1-phenylquinolinium, 2-ethenyl- 1-phenylquinolinium, 2-methoxycarbonyl-1-phenylquinolinium, 3-fluoro-1-phenylquinolinium, 4-methyl-1-phenylquinolinium, 2- Methoxy-1- (p-tolyl) quinolinium, 2-phenoxy-1- (2-furanyl) quinolinium, 2-ethylfluorenyl-1- (2-thienyl) quinolinium , 2-methoxycarbonyl-1- Quinolinium-yl, 3-fluoro-1-ethyl quinolinium, 1-isopropyl-4-methyl quinolinium like.

Corresponding to onium cations (isoquinolinium cations) of the general formula (9): Examples of isoquinolinium cations: Although the following can be listed, they are not limited to the following: N-phenylisoquinolinium, N -Methylisoquinolinium, N-ethylisoquinolinium, N- (o-chlorophenyl) isoquinolinium, N- (m-chlorophenyl) isoquinolinium, N- (p-cyanobenzene Group) isoquinolinium, N- (o-nitrophenyl) isoquinolinium, N- (p-ethylfluorenyl) isoquinolinium, N- (p-isopropylphenyl) isoquinolinium , N- (p-octadecyloxyphenyl) isoquinolinium, N- (p-methoxycarbonylphenyl) isoquinolinium, N- (9-anthryl) isoquinolinium, 1,2 -Diphenylisoquinolinium, N- (2-furyl) isoquinolinium, N- (2-thienyl) isoquinolinium, N-naphthylisoquinolinium, and the like.

Corresponds to an onium cation (benzo Azolium cation, benzothiazolium cation): benzo Examples of azolium cations: Although the following may be mentioned, they are not limited to them: N-methylbenzo Azolium, N-ethylbenzo Azolium, N-naphthylbenzo Azolium, N-phenylbenzo Azolium, N- (p-fluorophenyl) benzo Azolium, N- (p-chlorophenyl) benzo Azolium, N- (p-cyanophenyl) benzo Azolium, N- (o-methoxycarbonylphenyl) benzo Azolium, N- (2-furyl) benzo Azolium, N- (o-fluorophenyl) benzo Azolium, N- (p-cyanophenyl) benzo Azolium, N- (m-nitrophenyl) benzo Azolium, N- (p-isopropoxycarbonylphenyl) benzo Azolium, N- (2-thienyl) benzo Azolium, N- (m-carboxyphenyl) benzo Azolium, 2-mercapto-3-phenylbenzo Azolium, 2-methyl-3-phenylbenzo Azolium, 2-methylthio-3- (4-phenylsulfanylphenyl) benzo Azolium, 6-hydroxy-3- (p-tolyl) benzo Azolium, 7-mercapto-3-phenylbenzo Azolium, 4,5-difluoro-3-ethylbenzo Azolium and the like.

Examples of benzothiazolium cations: Although the following may be mentioned, they are not limited thereto: N-methylbenzothiazolium, N-ethylbenzothiazolium, N-phenylbenzothiazolium, N -(1-naphthyl) benzothiazolium, N- (p-fluorophenyl) benzothiazolium, N- (p-chlorophenyl) benzothiazolium, N- (p-cyanophenyl) benzothiazolium Onium, N- (o-methoxycarbonylphenyl) benzothiazolium, N- (p-tolyl) benzothiazolium, N- (o-fluorophenyl) benzothiazolium, N- (m-nitrobenzene Yl) benzothiazolium, N- (p-isopropoxycarbonylphenyl) benzothiazolium, N- (2-furyl) benzothiazolium, N- (4-methylthiophenyl) benzene Benzothiazolium, N- (4-phenylsulfanylphenyl) benzothiazolium, N- (2-naphthyl) benzothiazolium, N- (m-carboxyphenyl) benzothiazolium, 2- Mercapto-3-phenylbenzothiazolium, 2-methyl-3-phenylbenzothiazolium, 2-methylthio-3-phenylbenzothiazolium, 6-hydroxy-3-phenylbenzene Benzothiazolium, 7-mercapto-3-phenylbenzothiazolium, 4,5-difluoro-3-phenylbenzothiazolium, and the like.

Corresponding to an onium cation (furanyl or thienylsulfonium cation) of the general formula (11): Although the following may be listed, they are not limited to the following: difurylsulfonium, dithienylsulfonium, bis (4,5- Dimethyl-2-furyl) fluorene, bis (5-chloro-2-thienyl) fluorene, bis (5-cyano-2-furanyl) fluorene, bis (5-nitro-2-thienyl) Fluorene, bis (5-ethylfluorenyl-2-furanyl) fluorene, bis (5-carboxy-2-thienyl) fluorene, bis (5-methoxycarbonyl-2-furanyl) fluorene, bis (5- Phenyl-2-furyl) fluorene, bis (5- (p-methoxyphenyl) -2-thienyl) fluorene, bis (5-vinyl-2-furyl) fluorene, bis (5-ethynyl) -2-thienyl) fluorene, bis (5-cyclohexyl-2-furanyl) fluorene, bis (5-hydroxy-2-thienyl) fluorene, bis (5-phenoxy-2-furanyl) fluorene, Bis (5-mercapto-2-thienyl) Fluorene, bis (5-butylthio-2-thienyl) fluorene, bis (5-phenylthio-2-thienyl) fluorene, and the like.

Corresponding to an onium cation (diarylsulfonium cation) of the general formula (12): Although the following may be mentioned, it is not limited thereto: diphenylsulfonium, bis (p-tolyl) fluorene, bis (p-octyl) Phenyl) fluorene, bis (p-octadecylphenyl) fluorene, bis (p-octyloxyphenyl) fluorene, bis (p-octadecyloxyphenyl) fluorene, phenyl (p-octadecyloxyphenyl) Phenyl) fluorene, 4-isopropyl-4'-methyldiphenylfluorene, (4-isobutylphenyl) -p-tolylfluorene, bis (1-naphthyl) fluorene, bis (4-benzene Sulfanylphenyl) fluorene, phenyl (6-benzylidene-9-ethyl-9H-carbazol-3-yl) fluorene, (7-methoxy-2- pendantoxy-2H- Benzopiperan-3-yl) -4'-isopropylphenylphosphonium and the like.

Next, for the counter anion of the general formula X (3) ^- A will be described.

Counter anion of the general formula (3) X ^- in, although not particularly limited in principle, but preferably a non-nucleophilic anion. When the relative anion X ^{-is a} non-nucleophilic anion, it is difficult to produce a nucleophilic reaction on cations coexisting in the molecule or various materials used in combination. As a result, the photoacid generator represented by the general formula (2) itself or The composition obtained by using it has improved stability over time. The non-nucleophilic anion described herein refers to an anion having a low ability to produce a nucleophilic reaction. Include anions such _{^{as: PF 6 -, SbF 6 -}} , AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 -, ClO 4 -, an amine disulfide formate anion, SCN ^- and the like.

Among the exemplified anions described above, examples of the relatively preferred anion X ⁻ in the general formula (3) include PF ₆ ⁻ , SbF ₆ ⁻ and AsF ₆ ⁻ , and particularly preferred examples include PF ₆ ⁻ and SbF ₆ ⁻ .

Therefore, specific examples of the preferred onium salt constituting the photoacid generator (H) of the present invention are specific examples of the structure of the onium cation represented by the general formula (3) to general formula (12) illustrated above, is selected from _{^{PF 6 -, SbF 6 -,}} AsF 6 -, SbCl 6 -, BiCl 5 -, SnCl 6 - anion of the onium salt consisting of ^-, ClO ₄ ^-, an amine disulfide formate anion, SCN.

Specifically, the following can be cited as preferable specific examples of the photoacid generator (H) of the present invention: "Cyracure UVI-6992", "Cyracure UVI-6974" (above, manufactured by Dow Chemical Japan Co., Ltd.) ), "Adeka Optomer SP150", "Adeka Optomer SP152", "Adeka Optomer SP170", "Adeka Optomer SP172" (above, manufactured by ADEKA Co., Ltd.), "IRGACURE 250" (manufactured by Siebard Chemical Co., Ltd.), "CI -5102 "," CI-2855 "(above, manufactured by Soda Co., Ltd.)," San-Aid SI-60L "," San-Aid SI-80L "," San-Aid SI-100L "," San-Aid SI -110L "," San-Aid SI-180L "(above, manufactured by Sanxin Chemical Co., Ltd.)," CPI-100P "," CPI-100A "(above, manufactured by San-Apro Co., Ltd.)," WPI-069 " , "WPI-113", "WPI-116", "WPI-041", "WPI-044", "WPI-054", "WPI-055", "WPAG-281", "WPAG-567", " WPAG-596 "(above, manufactured by Wako Pure Chemical Industries, Ltd.).

The content of the photoacid generator (H) is preferably 0.01 to 10 parts by weight, and more preferably 0.05 to 5 parts by weight, relative to 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. It is particularly good at 0.1 ~ 3 parts by weight.

Among the aforementioned active energy ray-curable adhesives, it is preferable to use the photo-acid generator (H) and an alkoxy group in the active energy ray-curable adhesives. Compound (I), which is either a radical or an epoxy group.

(Compounds and polymers with epoxy groups) (I)

When a compound having one or more epoxy groups in a molecule or a polymer (epoxy resin) having two or more epoxy groups in a molecule is used, it is also possible to use a compound having two or more reactive groups in the molecule. Functional compounds. Here, the functional group reactive with the epoxy group may include, for example, a carboxyl group, a phenolic hydroxyl group, a mercapto group, a first-order or second-order aromatic amine group, and the like. Considering the three-dimensional hardenability, it is particularly preferred that these functional groups have two or more in one molecule.

Examples of the polymer having more than one epoxy group in the molecule include epoxy resins, which are bisphenol A epoxy resins derived from bisphenol A and epichlorohydrin, and bisphenols derived from bisphenol F and epichlorohydrin. F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin , Alicyclic epoxy resin, diphenyl ether epoxy resin, hydroquinone epoxy resin, naphthalene epoxy resin, biphenyl epoxy resin, fluorene epoxy resin, 3-functional epoxy resin, 4 Multifunctional epoxy resins such as functional epoxy resins, desiccyl glyceryl ester epoxy resin, desiccyl glyceryl amine epoxy resin, hydantoin type epoxy resin, trimeric isocyanate type epoxy resin, Aliphatic chain epoxy resins, etc. These epoxy resins may also be halogenated and hydrogenated. Commercially available epoxy resin products include, for example, JER Epikote 828, 1001, 801N, 806, 807, 152, 604, 630, 871, YX8000, YX8034, YX4000, and DIC Corporation manufactured by Japan Epoxy Resin Co., Ltd. Epiclon 830, EXA835LV, HP4032D, HP820, EP4100 series, EP4000 series, EPU series made by ADEKA Co., Ltd. Column, Celloxide series (2021, 2021P, 2083, 2085, 3000, etc.) manufactured by Daicel Chemical Co., Ltd., Epolead series, EHPE series, YD series, YDF series, YDCN series, YDB series, benzene manufactured by Nippon Steel Chemical Co., Ltd. Epoxy resins (polyhydroxy polyethers synthesized from bisphenols and epichlorohydrin have epoxy groups at both ends; YP series, etc.), Denacol series manufactured by Nagase chemteX, Epolight series manufactured by Kyoeisha Chemical Co., etc. , But not limited to them. These epoxy resins may be used in combination of two or more. Furthermore, when calculating the glass transition temperature Tg of the adhesive layer, the compound having an epoxy group and the polymer (H) are not included in the calculation.

(Compounds and polymers with alkoxy groups) (I)

The compound having an alkoxy group in the molecule is not particularly limited as long as it has one or more alkoxy groups in the molecule, and a known one can be used. Examples of such a compound include a melamine compound, an amine resin, and the like.

The compounding amount of the compound (I) containing either an alkoxy group or an epoxy group is usually 30 parts by weight or less based on 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. When the content of the compound (I) in the composition is too large, the adhesiveness may be reduced, and the impact resistance to a drop test may be deteriorated. The content of the compound (I) in the composition is more preferably 20 parts by weight or less. On the other hand, from the viewpoint of the water resistance of the cured material layer (adhesive layer 2a), the composition preferably contains 2 parts by weight or more of the compound (I), and more preferably contains 5 parts by weight or more.

When the active energy ray-curable adhesive related to the low-elasticity adhesive layer (a) of the present invention is used in the form of an electron beam-curable type, the composition does not particularly need to contain a photopolymerization initiator, but the UV hardening In the case of using the type, it is preferable to use a photopolymerization initiator, and it is particularly preferable to use a photopolymerization initiator having a high sensitivity to light of 380 nm or more. The photopolymerization initiator having a high sensitivity to light of 380 nm or more will be described later.

In the active energy ray hardening type adhesive related to the low-elasticity adhesive layer (a) of the present invention, as the photopolymerization initiator, the compound represented by the aforementioned general formula (1) is preferably used alone;

(Wherein R ¹ and R ² represent -H, -CH _2b H ₃ , -iPr or Cl, and R ¹ and R ² may be the same or different), or a compound represented by the general formula (1) and a compound described later may be used in combination Photopolymerization initiator with high sensitivity to light above 380nm. When using the compound represented by General formula (1), compared with the case where the photoinitiator which has high sensitivity with respect to the light of 380 nm or more is used alone, it is excellent in adhesiveness. Among the compounds represented by the general formula (1), R ¹ and R ² are also diethyl 9-oxysulfur of -CH _2b H ₃ Especially good. The composition ratio of the compound represented by the general formula (1) in the composition is preferably 0.1 to 5.0 parts by weight, and 0.5 to 0.5 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. ~ 4.0 parts by weight is more preferred, and 0.9 ~ 3.0 parts by weight is even more preferred.

In addition, it is preferable to add a polymerization initiator as needed. Gather together Examples of starting auxiliaries include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, and 4-diamine. Ethyl methylaminobenzoate, isoamyl 4-dimethylaminobenzoate, etc., and ethyl 4-dimethylaminobenzoate is particularly preferred. When using a polymerization initiation adjuvant, the addition amount is usually 0 to 5 parts by weight, preferably 0 to 4 parts by weight, relative to 100 parts by weight of the total amount of the radical polymerizable compound in the active energy ray-curable adhesive. , And the best is 0 ~ 3 parts by weight.

Moreover, a well-known photopolymerization initiator can be used together as needed. The photopolymerization initiator is preferably a photopolymerization initiator having a high sensitivity to light of 380 nm or more. Specifically, 2-methyl-1- (4-methylthiophenyl) -2- Phenylpropane-1-one, 2-benzyl-2-dimethylamino-1- (4- Phenylphenyl) -butanone-1, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4- Phenyl) phenyl] -1-butanone, 2,4,6-trimethylbenzylidene-diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzylidene) -Phenylphosphine oxide, bis (H5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium Wait.

In particular, as the photopolymerization initiator, in addition to the photopolymerization initiator of the general formula (1), a compound represented by the following general formula (2) may be appropriately used;

(Wherein R ³ , R ⁴ and R ⁵ represent -H, -CH _3b H _2b H ₃ , -iPr or Cl, and R ³ , R ⁴ and R ⁵ may be the same or different). The compound represented by the general formula (2) may be 2-methyl-1- (4-methylthiophenyl) -2-, which is also commercially available. Porphyrin-1-one (trade name: IRGACURE 907 manufacturer: BASF). In addition, 2-benzyl-2-dimethylamino-1- (4- Phenylphenyl) -butanone-1 (trade name: IRGACURE 369 manufacturer: BASF), 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [ 4- (4- Phenyl) phenyl] -1-butanone (trade name: IRGACURE 379 manufacturer: BASF) is preferred because of its high sensitivity.

In addition, the active energy ray-curable adhesive agent related to the low-elasticity adhesive layer (a) of the present invention can be blended with various additives as long as it does not impair the object and effect of the present invention. . Examples of such additives include epoxy resins, polyamides, polyamides, imines, polyurethanes, polybutadiene, polychloroprene, polyethers, polyesters, and styrene-butadiene. Polymers or oligomers of olefin block copolymers, petroleum resins, xylene resins, ketone resins, cellulose resins, fluorine-based oligomers, silicone-based oligomers, polysulfide-based oligomers, etc .; Morphine Polymerization inhibitors such as 2,6-di-tert-butyl-4-methylphenol; polymerization initiation aids; leveling agents; wetting improvers; surfactants; plasticizers; ultraviolet absorbers; inorganic Fillers; pigments; dyes, etc.

The active energy ray hardening type adhesive according to the present invention is hardened by irradiating the active energy ray to form a low-elasticity adhesive layer (a).

As the active energy ray, visible rays including an electron beam and a wavelength range of 380nm to 450nm can be used. Furthermore, although the long wavelength limit of visible light is about 780 nm, visible light greater than 450 nm will only help to concentrate It can be absorbed by the initiator and cause fever. Therefore, in the present invention, it is preferable to use a band-pass filter to block visible light on a long wavelength side greater than 450 nm.

The electron beam irradiation conditions may be any appropriate conditions as long as the above-mentioned active energy ray-curable adhesive can be cured. For example, the acceleration voltage of the electron beam irradiation is preferably 5 kV to 300 kV, and more preferably 10 kV to 250 kV. When the acceleration voltage is less than 5kV, the electron beam may not be transmitted to the adhesive and may be insufficiently hardened. If the acceleration voltage is more than 300kV, the penetration force of the sample will be too strong, and it will affect the polarizing film (P) and optics. The film (3) may cause damage. The irradiation dose is 5 to 100 kGy, and more preferably 10 to 75 kGy. When the irradiation dose is less than 5kGy, the adhesive will become insufficiently hardened. If it exceeds 100kGy, it will cause damage to the polarizing film (P) and optical film (3), reduce mechanical strength and cause yellowing, and fail to obtain the predetermined optical characteristic.

Electron beam irradiation is usually performed in an inert gas, but if necessary, it may be performed in the atmosphere or under a condition of introducing a little oxygen. Depending on the material of the transparent protective film, oxygen can be forcibly generated on the surface of the transparent protective film initially encountered by the electron beam by appropriate introduction of oxygen, which can prevent damage to the transparent protective film and effectively only The agent then irradiates an electron beam.

However, in the method for manufacturing a laminated polarizing film related to the present invention, in order to improve the adhesion performance of the low-elasticity adhesive layer (a) between the polarizing film (P) and the optical film (3), and prevent the polarizing film (P) Curled, active energy lines are those using visible light with a wavelength range of 380nm ~ 450nm. The active energy ray with the most exposure to visible light in the wavelength range of 380nm ~ 450nm is particularly good. When the transparent protective film or optical film (3) of the polarizing film (P) uses a film (ultraviolet non-transmissive film) that imparts ultraviolet absorption energy, the absorption ratio of the transparent protective film or optical film (3) is 380 nm. Light with a shorter wavelength will be converted into heat, which will cause the transparent protective film or optical film (3) to generate heat, thereby causing defects such as curling and wrinkling of the laminated polarizing film. Therefore, in the present invention, the active energy ray generating device is preferably a device that does not emit light having a shorter wavelength than 380 nm. More specifically, the integrated illuminance and wavelength range of 250 to 440 nm are preferred. The ratio of the accumulated illuminance at 370 nm is 100: 0 to 100: 50, and more preferably 100: 0 to 100: 40. The active energy ray that satisfies such a cumulative illuminance relationship is preferably a metal halide lamp enclosed in gallium and an LED light source that emits light in a wavelength range of 380 to 440 nm. Alternatively, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, incandescent lamps, xenon lamps, halogen lamps, carbon arc lamps, metal halide lamps, fluorescent lamps, tungsten lamps, gallium lamps, excimer mines Or sunlight as a light source, and use a band-pass filter to block light with a shorter wavelength than 380nm. In order to improve the adhesion performance of the adhesive layer between the polarizing film (P) and the optical film (3) and the low-elasticity adhesive layer (a), and to prevent the curling of the polarizing film, it is preferable to use a blocking ratio of 400 nm. Active energy rays obtained from bandpass filters with shorter wavelengths of light, or active energy rays with wavelengths of 405nm obtained using LED light sources.

In the visible light hardening type, it is preferable to heat the active energy ray hardening type adhesive (warming before irradiation) before irradiating visible light. In this case, it is better to warm to 40 ° C or higher, and to warm to 50 ° C. The above is better. Also, in the irradiation The active energy ray hardening type adhesive (heating after irradiation) after visible light irradiation is also preferable. At this time, it is better to warm to 40 ° C or higher, and more preferably to 50 ° C or higher.

The active energy ray hardening type adhesive related to the low-elasticity adhesive layer (a) can irradiate ultraviolet rays through the optical film (3) having UV absorption energy by containing the photopolymerization initiator of the general formula (1), The low-elasticity adhesive layer (a) is hardened and formed. The optical film (3) can use a light transmittance with a wavelength of 365 nm of less than 5%.

The method for imparting UV absorbing energy to the optical film (3) includes a method of including an ultraviolet absorber in the optical film (3), or a method of laminating a surface treatment layer containing an ultraviolet absorber on the surface of the optical film (3). .

Specific examples of the ultraviolet absorber include, for example, an oxybenzophenone-based compound, a benzotriazole-based compound, a salicylate-based compound, a benzophenone-based compound, and a cyanoacrylate-based compound, which are conventionally known. Compounds, nickel salt compounds, three Department of compounds and so on.

The method for manufacturing a laminated polarizing film related to the present invention includes the following steps: a coating step, which is a step of laminating the transparent protective film (2) on the side of the aforementioned low elastic adhesive layer (a) in the aforementioned polarizing film (P) and At least one side of the optical film (3) is coated with an active energy ray-curable adhesive to form the low-elasticity adhesive layer (a); the bonding step is to bond the polarizing film (P) and the optical film (3). ; And a subsequent step, which is followed by the aforementioned low-elasticity adhesive layer (a) The light film (P) and the optical film (3), wherein the low-elasticity adhesive layer (a) is obtained by hardening the active energy ray-curable adhesive by irradiating the active energy ray.

The transparent protective film (2) and optical film (3) in the polarizing film (P) may be subjected to surface modification treatment before the aforementioned active energy ray-curable adhesive is applied. Specific treatments include treatments by corona treatment, plasma treatment, saponification treatment, excimer treatment, or flame treatment.

The coating method of the active energy ray-curable adhesive can be appropriately selected depending on the viscosity of the composition or the thickness for the purpose. Examples of the coating method include, for example, a reverse coater, a gravure coater (front, reverse, or flat), a reverse bar coater, a roll coater, a die coater, a bar coater, a rod coater, and the like. In addition, a method such as a dipping method can be suitably used for the coating.

The polarizing film (P) and the optical film (3) are adhered by the adhesive applied as described above. The polarizing film (P) and the optical film (3) can be bonded by a roll laminator or the like.

After the polarizing film (P) is bonded to the optical film (3), the active energy ray (electron beam, ultraviolet rays, visible light, etc.) is irradiated to harden the active energy ray-curable adhesive to form a low-elastic adhesive layer (a). . The irradiation direction of the active energy rays (electron beam, ultraviolet rays, visible rays, etc.) can be irradiated from any appropriate direction. The irradiation is preferably performed from the optical film (3) side. If irradiation is performed from the polarizing film (P) side, the polarizing film (P) may be deteriorated by active energy rays (electron beam, ultraviolet rays, visible light, etc.).

When manufacturing a laminated polarizing film related to the present invention in a continuous production line, although the production line speed depends on the curing time of the adhesive, the 1 ~ 500m / min is better, 5 ~ 300m / min is better, and 10 ~ 100m / min is even better. When the production line speed is too small, the productivity is poor, or the polarizing film (P) and the optical film (3) are damaged too much, making it impossible to produce a polarizing film that can withstand durability tests and the like. When the production line speed is too high, the adhesive hardening may become insufficient, and the intended adhesiveness may not be obtained.

<Polarizing film>

As described above, the polarizing film (P) is provided with a transparent protective film (2) on at least one side of the polarizer (1) through the adhesive layer (b).

<Polarizer>

The polarizer (1) is not particularly limited and various polarizers can be used. Examples of polarizers include iodine and dichroic dyes on hydrophilic polymer films such as polyvinyl alcohol films, partially formaldehyde polyvinyl alcohol films, and ethylene / vinyl acetate copolymer partially saponified films. Polychromatic materials such as uniaxial stretchers, dehydration treatment products of polyvinyl alcohol, or dehydrochlorination treatment products of polyvinyl chloride, etc., are adsorbed on the color material and subjected to polyaxially oriented films. Among them, a polarizer made of a polyvinyl alcohol film and a dichroic material such as iodine is more suitable. Although the thickness of these polarizers is not particularly limited, it is generally about 80 μm or less.

A polarizer made by dyeing a polyvinyl alcohol-based film with iodine and extending it in one axis can be made, for example, by immersing polyvinyl alcohol in an aqueous solution of iodine to dye, and extending it to 3 to 7 times its original length. If necessary, it can be immersed in an aqueous solution of boric acid, potassium iodide and the like. If necessary, the polyvinyl alcohol-based film may be immersed in water and washed with water before dyeing. In addition to washing the polyvinyl alcohol-based film with water, the dirt or resistance on the surface of the polyvinyl alcohol-based film can be cleaned. The agglomerating agent also has the effect of swelling the polyvinyl alcohol-based film to prevent uneven dyeing and the like. The extension system may be performed after dyeing with iodine, or may be extended while dyeing, or may be dyed with iodine while extending. The stretching may be performed in an aqueous solution such as boric acid or potassium iodide or in a water bath.

As the polarizer, a thin polarizer having a thickness of 10 μm or less can be used. From the viewpoint of thinning, the thickness is preferably 1 to 7 μm. Such a thin polarizer is excellent in durability because it has less variation in thickness, excellent visibility, and small dimensional changes, and it is also desirable from the viewpoint of reducing the thickness of a polarizing film. In addition, the thin polarizer can easily reduce the moisture content during heating and drying, so it can be suitably used as a polarizer with a moisture content of 15% or less.

Typical examples of the thin polarizer include: Japanese Patent Laid-Open No. 51-069644, Japanese Patent Laid-Open No. 2000-338329, WO2010 / 100917 booklet, PCT / JP2010 / 001460 specification, or Japanese Patent Laid-Open 2010 The thin polarizing film described in the specification No. -269002 and Japanese Patent Application No. 2010-263692. These thin polarizing films can be obtained by a manufacturing method including a step of stretching a polyvinyl alcohol-based resin (hereinafter also referred to as a PVA-based resin) layer and a stretching resin substrate in a state of a laminate and a dyeing step. According to this production method, even if the PVA-based resin layer is thin, it can be supported by the resin substrate for stretching, and it will not be stretched in a poor state such as breakage caused by stretching.

In the manufacturing method including the step of stretching in the state of the laminated body and the dyeing step, from the viewpoint of being able to be stretched to a high magnification and improving the polarization performance, the thin polarizing film is preferably a small-sized polarizing film by WO2010 / 100917. It is obtained by a manufacturing method including a step of extending in a boric acid solution as described in the booklet, the specification of PCT / JP2010 / 001460 or the specification of Japanese Patent Application No. 2010-269002 and the Japanese Patent Application No. 2010-263692. It is preferably obtained by a manufacturing method described in Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692, which include a step of assisting in-air stretching before stretching in a boric acid aqueous solution.

The thin, high-performance polarizing film described in the aforementioned PCT / JP2010 / 001460 specification is made of a PVA-based resin with a thickness of 7 μm or less formed by integrally forming a film on a resin substrate and aligning a dichroic substance. Thin, high-performance polarizing film with optical characteristics of single transmittance above 42.0% and polarization degree above 99.95%.

The thin, high-performance polarizing film can be formed on a resin substrate having a thickness of at least 20 μm by coating and drying a PVA-based resin, and immersing the generated PVA-based resin layer in a dichroism In the dyeing solution of the substance, the dichroic substance is adsorbed on the PVA-based resin layer, and the PVA-based resin layer on which the dichroic substance is adsorbed in the aqueous boric acid solution is extended integrally with the resin substrate to extend the total extension ratio. It is made more than 5 times the original length.

In addition, the aforementioned thin, high-function polarizing film can be manufactured by a method of manufacturing a thin, high-function polarizing film including a dichroic substance aligned, the method including the step of generating a multilayer film, the laminated body The film includes a resin substrate having a thickness of at least 20 μm, and is formed by coating and drying an aqueous solution containing a PVA-based resin on one side of the resin substrate PVA-based resin layer; the laminate film containing the resin substrate and the PVA-based resin layer formed on one side of the resin substrate is immersed in a dyeing solution containing a dichroic substance, so that the laminate film is The step of adsorbing a dichroic substance on the PVA-based resin layer contained in the above; in the boric acid aqueous solution, the aforementioned laminated body film including the PVA-type resin layer having the dichroic substance adsorbed is formed so that the total length becomes 5 The stretching step is performed at a multiple of or more; by integrally extending the PVA-based resin layer to which the dichroic substance is adsorbed and the resin substrate, and forming a film on one side of the resin substrate, the dichroic substance is aligned. A thin, high-performance polarizing film composed of a completed PVA-based resin layer, having a thickness of 7 μm or less, and having optical characteristics of a monomer transmittance of 42.0% or more and a polarization degree of 99.95% or more, thereby manufacturing a laminated body film.

The thin polarizing film of the aforementioned Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692 is a polarizing film of a continuous network composed of a PVA-based resin in which dichroic materials are aligned, and It is a laminate of PVA-based resin layer formed by filming on an amorphous ester-based thermoplastic resin base material. It is extended by two steps of air-assisted stretching and boric acid water stretching to form 10 μm. The following thicknesses. Such a thin polarizing film is preferably made so that when the unit transmittance is T and the polarization degree is P, P>-(100.929T-42.4-1) × 100 (but T <42.3) and Optical characteristics with a condition of P ≧ 99.9 (but T ≧ 42.3).

Specifically, the aforementioned thin polarizing film can be manufactured by a thin polarizing film manufacturing method including the following steps: a PVA-based resin formed by forming an amorphous ester-based thermoplastic resin substrate on a continuous web Layers High-temperature stretching in the air to generate an extended intermediate product composed of an aligned PVA-based resin layer; by adsorbing the dichroic substance to the extended intermediate product, a dichroic substance (preferably It is iodine or a mixture of iodine and organic dyes) a colored intermediate product composed of a PVA-based resin layer; by extending the colored intermediate product in boric acid water to generate a dichroic material A step of a polarizing film made of a PVA-based resin layer and having a thickness of 10 μm or less.

In this manufacturing method, the total elongation ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin substrate obtained by high-temperature air stretching and boric acid water stretching is desired to be 5 times or more. The liquid temperature of the boric acid aqueous solution used for the extension of boric acid water can be set above 60 ° C. Before the colored intermediate product is stretched in the boric acid aqueous solution, it is desirable to apply insolubilization treatment to the colored intermediate product. At this time, it is desirable to immerse the colored intermediate product in a boric acid aqueous solution having a liquid temperature of not higher than 40 ° C. Come on. The amorphous ester-based thermoplastic resin substrate may be an amorphous polyethylene terephthalate including: a copolymerized polyethylene terephthalate obtained by copolymerizing isophthalic acid. Diester, copolymerized polyethylene terephthalate or other copolymerized polyethylene terephthalate, obtained by copolymerizing cyclohexanedimethanol; and preferably composed of a transparent resin, and The thickness is made to be 7 times or more of the thickness of the PVA-based resin layer formed. In addition, the stretching ratio of high-temperature stretching in the air is preferably 3.5 times or less, and the stretching temperature of the high-temperature stretching in the air is preferably higher than the glass transition temperature of the PVA-based resin. Specifically, the range is from 95 ° C to 150 ° C. good. When the high-temperature extension in the air is performed with the free end and one axis extending, the film formed on the amorphous ester thermoplastic resin substrate The total stretching ratio of the PVA-based resin layer is preferably 5 times or more and 7.5 times or less. In addition, when performing aerial high-temperature extension with one-axis extension of the fixed end, the total extension ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin substrate is preferably 5 times or more and 8.5 times or less.

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

A base material of a continuous web of isophthalic acid copolymerized polyethylene terephthalate (amorphous PET) obtained by copolymerizing 6 mol% of isophthalic acid was prepared. The glass transition temperature of the amorphous PET is 75 ° C. A laminated body composed of a continuous PET amorphous base material and a polyvinyl alcohol (PVA) layer was produced as follows. Incidentally, the glass transition temperature of PVA is 80 ° C.

A 200 μm-thick amorphous PET substrate was prepared, and a 4 to 5% concentration PVA aqueous solution in which PVA powder having a polymerization degree of 1,000 or more and a saponification degree of 99% or more was dissolved in water was prepared. Next, a 200 μm-thick amorphous PET substrate was coated with an aqueous PVA solution and dried at a temperature of 50 to 60 ° C. to obtain a laminated body having a 7 μm-thick PVA layer formed on the amorphous PET substrate.

A laminated body including a 7 μm-thick PVA layer was subjected to the following steps including a two-step extension step of air-assisted extension and boric acid water extension to produce a thin, high-function polarizing film with a thickness of 3 μm. Through the air-assisted extension step in the first step, the laminated body including the 7 μm thick PVA layer and the amorphous PET substrate were integrally extended to generate an extended laminated body including the 5 μm thick PVA layer. Specifically, this extended laminated body is a laminated body including a 7 μm-thick PVA layer placed in an extended device equipped with an oven set to an extended temperature environment of 130 ° C, and a free end is performed so that the extended magnification becomes 1.8 times Extender. By this stretching treatment, the PVA layer contained in the stretched laminate is changed. Formed into a 5 μm thick PVA layer with PVA molecules aligned.

Next, a dyeing step is performed to generate a colored laminated body in which iodine is adsorbed on a 5 μm-thick PVA layer in which PVA molecules are aligned. Specifically, the colored laminated body is immersed at 30 ° C. of the extended laminated body at an arbitrary time so that the monomer transmittance of the PVA layer constituting the finally produced high-performance polarizing film becomes 40 to 44%. In the dyeing solution containing iodine and potassium iodide, the iodine is adsorbed on the PVA layer contained in the extended laminate. In this step, the dyeing liquid system uses water as a solvent, sets the iodine concentration in the range of 0.12 to 0.30% by weight, and sets the potassium iodide concentration in the range of 0.7 to 2.1% by weight. The concentration ratio of iodine to potassium iodide is 1 to 7. Incidentally, potassium iodide is required to dissolve iodine in water. More specifically, by immersing the extended laminated body in a dyeing solution having an iodine concentration of 0.30% by weight and a potassium iodide concentration of 2.1% by weight for 60 seconds, a colored deposition layer capable of adsorbing iodine to a 5 μm-thick PVA layer in which PVA molecules are aligned can be generated body.

In addition, through the boric-acid-water-extension step in the second step, the colored laminated body and the amorphous PET substrate were further integrally extended to produce an optical film laminate including a PVA layer constituting a high-function polarizing film with a thickness of 3 μm. Specifically, the optical film laminate is an extension device equipped with a treatment device set in a boric acid aqueous solution containing boric acid and potassium iodide in a liquid temperature range of 60 to 85 ° C. at an extension ratio of 3.3. The way to carry the free end is to extend the axis. More specifically, the liquid temperature of the aqueous boric acid solution was 65 ° C. The boric acid content was set to 4 parts by weight with respect to 100 parts by weight of water, and the potassium iodide content was set to 5 parts by weight with respect to 100 parts by weight of water. In this step, the colored layered body with adjusted iodine adsorption amount is first immersed Dip in m-boric acid solution for 5-10 seconds. Then, the colored laminated body was directly passed between the extension devices (complex array rollers having different peripheral speeds) provided in the processing device, and it took 30 to 90 seconds to perform free-end uniaxial extension so that the extension ratio became 3.3 times. By this extension treatment, the PVA layer contained in the colored laminated body is changed into a 3 μm-thick PVA layer formed by adsorption of iodine as a polyiodide ion complex and high-order orientation in one direction. This PVA layer is a high-performance polarizing film constituting an optical film laminate.

Although it is not a necessary step for the manufacture of optical film laminates, it is preferred that the optical film laminates be taken out of the boric acid aqueous solution through a washing step, and a 3 μm thick PVA film formed on an amorphous PET substrate The boric acid attached to the surface of the layer was washed with an aqueous potassium iodide solution. Then, the washed optical film laminate was dried by a drying step performed with warm air at 60 ° C. The washing step is a step for removing appearance defects such as the precipitation of boric acid.

Similarly, although it is not a necessary step for the manufacture of an optical film laminate, it can be coated on the surface of a 3 μm-thick PVA layer formed on an amorphous PET substrate by an adhesion and / or transfer step while being coated. After the adhesive was adhered to the 80 μm-thick triacetylfluorene cellulose film, the amorphous PET substrate was peeled off, and the 3 μm-thick PVA layer was transferred to the 80 μm-thick triethylfluorene cellulose film.

[Other steps]

The manufacturing method of the aforementioned thin polarizing film may include other steps in addition to the aforementioned steps. Other steps include, for example, an insolubilization step, a cross-linking step, and a drying (adjusting the moisture content) step. Other steps can be performed at any appropriate time.

The said insolubilization process can be performed typically by immersing a PVA-type resin layer in a boric-acid aqueous solution. The insolubilization treatment can impart water resistance to the PVA-based resin layer. The concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight relative to 100 parts by weight of water. The liquid temperature of the insolubilization bath (aqueous boric acid solution) is preferably 20 ° C to 50 ° C. The insolubilization step is preferably performed after the production of the laminated body, and before the dyeing step or the elongation step in water.

The said crosslinking process can be performed typically by immersing a PVA-type resin layer in a boric-acid aqueous solution. By performing a crosslinking treatment, water resistance can be imparted to the PVA-based resin layer. The concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight relative to 100 parts by weight of water. When the crosslinking step is performed after the dyeing step, it is preferable to further blend iodide. By blending iodide, the elution of iodine adsorbed on the PVA-based resin layer can be suppressed. The blending amount of iodide is preferably 1 to 5 parts by weight relative to 100 parts by weight of water. Specific examples of the iodide are as described above. The liquid temperature of the crosslinking bath (aqueous boric acid solution) is preferably 20 ° C to 50 ° C. The cross-linking step is preferably performed before the second boric acid water elongation step. In a preferred embodiment, the dyeing step, the cross-linking step, and the second boric acid elongation step are sequentially performed.

<Transparent protective film>

As a material constituting the transparent protective film (2), for example, a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture blocking property, and isotropic properties can be used. Specific examples of such thermoplastic resins include cellulose resins such as triethyl cellulose, polyester resins, polyether resins, poly resins, polycarbonate resins, polyamide resins, and polyimide resins. , Polyolefin resin, (meth) acrylic resin, cyclic polyolefin resin (norbornene resin), polymer Aromatic resin, polystyrene resin, polyvinyl alcohol resin and mixtures thereof. The transparent protective film may contain one or more of any appropriate additives. Examples of the additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, anti-colorants, flame retardants, nucleating agents, antistatic agents, pigments, and colorants. The content of the aforementioned thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, and even more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. . When the content of the thermoplastic resin in the transparent protective film is 50% by weight or less, there is a possibility that the high transparency and the like originally possessed by the thermoplastic resin may not be sufficiently exhibited.

And, forming a transparent protective film (2) of the material system in transparency, mechanical strength, thermal stability, moisture blocking properties, isotropy, etc. is excellent is preferred, in particular in the moisture permeability 150g / m ² / 24h or less It is more preferable, and it is particularly preferable to be less than 140g / m ² / 24h, and it is more preferable to be less than 120g / m ² / 24h. The moisture permeability is determined by the method described in the examples.

When using the aforementioned polarizing film moisture permeability at 150g / when m ² / 24h or less of the transparent protective film, the moisture in the air is difficult to enter the polarizing film, the polarizing film while inhibiting moisture from the body of the rate change. As a result, curling or dimensional change of the polarizing film caused by the storage environment can be suppressed.

A functional layer such as a barcode layer, an anti-reflection layer, an anti-adhesion layer, a diffusion layer, and an anti-glare layer may be provided on the surface of the transparent protective film (2) that does not make the polarizer (1) adhere to. In addition, the foregoing functional layers such as the barcode layer, the anti-reflection layer, the anti-adhesion layer, the diffusion layer, or the anti-glare layer can be provided in addition to the transparent protective film (2) itself, or can be used as a transparent protective film (2) through other methods Separate things to set.

Although the thickness of the transparent protective film (2) can be appropriately determined, it is generally about 1 to 500 μm, preferably 1 to 300 μm, and 5 to 200 μm. Better. 10 to 200 μm is more preferable, and 20 to 80 μm is more preferable.

In addition, the transparent protective film (2) provided on both sides of the polarizer (1) may be a transparent protective film composed of the same polymer material on the surface or the surface, or a different polymer material on the surface of the polarizer (1). The formed transparent protective film.

As the transparent protective film, a retardation film having a retardation having a front retardation of 40 nm or more and / or a thickness direction retardation of 80 nm or more can be used. The front phase difference is usually controlled in the range of 40 ~ 200nm, and the thickness direction phase difference is usually controlled in the range of 80 ~ 300nm. When a retardation film is used as a transparent protective film, since this retardation film also functions as a transparent protective film, thickness reduction can be pursued.

Examples of the retardation film include a birefringent film obtained by subjecting a polymer material to uniaxial or biaxial stretching, an alignment film of a liquid crystal polymer, and a film supporting an alignment layer of a liquid crystal polymer. Although the thickness of the retardation film is not particularly limited, it is generally about 20 to 150 μm.

Furthermore, in the laminated polarizing films shown in FIGS. 1A and B and FIGS. 2 to 4, a retardation film can be used as the transparent protective film (2). In addition, the transparent protective films (2) on both sides of the polarizer (1) can be set as retardation films on one or both sides. In particular, in FIGS. 3 and 4, it is preferable to use a retardation film as the transparent protective film on the adhesive layer (b2) side. In particular, when a retardation film is used as the transparent protective film (2) on both sides, the state shown in FIG. 4 is good.

<Adhesive layer (b)>

As long as the adhesive layer (b) is optically transparent, various types of water-based, solvent-based, hot-melt, and active energy ray hardening types can be used without particular limitation. As mentioned above, the adhesive layer (b) is preferably one which satisfies a predetermined thickness and a predetermined storage elastic modulus.

Examples of the water-based hardening type adhesive include vinyl polymer, gelatin, vinyl latex, polyurethane, isocyanate, polyester, and epoxy. Although an adhesive layer composed of such an aqueous adhesive can be formed as a coating or drying layer of an aqueous solution, a catalyst such as a cross-linking agent, other additives, or an acid may be blended as necessary when preparing the aqueous solution.

The water-based hardening type adhesive is preferably a vinyl polymer-containing adhesive or the like, and the vinyl polymer is preferably a polyvinyl alcohol-based resin. From the viewpoint of improving durability, a polyvinyl alcohol-based resin is more preferably an adhesive containing a polyvinyl alcohol-based resin having an ethylamidine group. The crosslinking agent that can be blended with the polyvinyl alcohol resin is preferably a compound having at least two functional groups reactive with the polyvinyl alcohol resin. For example: boric acid or borax, carboxylic acid compounds, alkanediamines; isocyanates; epoxys; monoaldehydes; dialdehydes; amino-formaldehyde resins; and salts of divalent or trivalent metals and Oxide. Water-soluble silicate can be blended in polyvinyl alcohol resin. Examples of the water-soluble silicate include lithium silicate, sodium silicate, and potassium silicate.

Various forms of active energy ray-curable adhesives can be used. In addition, active energy ray hardening type adhesives such as electron beam hardening type and ultraviolet hardening type can be exemplified. The UV-curable adhesive can be roughly classified into a radical polymerization-curable adhesive and a cationic polymerization-type adhesive. Moreover, a radical polymerization hardening type adhesive can be used as a thermosetting type adhesive. As the active energy ray-curable adhesive used in the formation of the adhesive layer (b), the active energy ray-curable adhesive used in the formation of the low-elasticity adhesive layer (a) can be used.

Among the aforementioned adhesive layers (b), the adhesive layer (b1) is preferably a polyvinyl alcohol-based adhesive. The adhesive layer (b2) is preferably an active energy ray-curable adhesive.

The aforementioned adhesive for forming the low-elasticity adhesive layer (a) or the adhesive layer (b) may include an additive as necessary. Examples of the additive include a coupling agent such as a silane coupling agent, a titanium coupling agent, an adhesion promoter typified by ethylene oxide, an additive that improves wettability with a transparent film, a propylene hydroxide compound, or a hydrocarbon-based (natural , Synthetic resin) and other representative additives that can improve mechanical strength or processability, UV absorbers, anti-aging agents, dyes, processing aids, ion trapping agents, antioxidants, adhesion-imparting agents, fillers (except metals Other than compound fillers), plasticizers, leveling agents, foam inhibitors, antistatic agents, heat stabilizers, hydrolytic stabilizers and other stabilizers.

Although the laminated polarizing film of the present invention uses a low-elasticity adhesive layer (a) to bond the polarizing film (P) and the optical film (3), it can also be used on the transparent protective film (2) and / or the optical film (3). Set up easy to attach layers. Moreover, an easy adhesion layer may be provided in the polarizing film (P) on the polarizer (1) and / or the transparent protective film (2).

The easy-adhesion layer may be, for example, various types including a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone system, a polyamide skeleton, a polyimide skeleton, and a polyvinyl alcohol skeleton. Resin to form. These polymer resins can be used singly or in combination of two or more kinds. Further, other additives may be added to the formation of the easy-adhesive layer. Specifically, stabilizers such as an adhesion-imparting agent, an ultraviolet absorber, an antioxidant, and a heat-resistant stabilizer may be further used. The thickness of the easy-adhesive layer after drying is preferably 0.01 to 5 μm, more preferably 0.02 to 2 μm, and still more preferably 0.05 to 1 μm. In addition, although a plurality of layers may be provided for the easy-adhesion layer, at this time, it is preferable that the total thickness of the easy-adhesion layer is within the aforementioned range.

<Optical film>

Examples of the optical film (3) other than the polarizer (1), such as liquid crystals such as retardation films (including wavelength plates such as 1/2 and 1/4), vision compensation films, brightness enhancement films, reflection plates, or anti-reflection plates Formed by an optical layer used in the formation of a display device and the like. The optical film (3) can be used in two or more layers. When two or more optical films are used, the above-mentioned low-elasticity adhesive layer (a) may be used as the laminated layer of the second optical film. The optical film (3) is preferably a retardation film.

The retardation film may be the same as that described above, and has a retardation having a front retardation of 40 nm or more and / or a thickness direction retardation of 80 nm or more. The front phase difference is usually controlled in the range of 40 ~ 200nm, while the thickness direction phase difference is usually controlled in the range of 80 ~ 300nm.

Examples of retardation films include birefringent films obtained by uniaxially or biaxially stretching polymer materials, and alignment films of liquid crystal polymers. A film, an alignment layer of a liquid crystal polymer supported by a thin film, and the like. Although the thickness of the retardation film is not particularly limited, it is generally about 20 to 150 μm.

An adhesive layer may be provided on the laminated polarizing film of the present invention to adhere to other materials such as a liquid crystal cell. Although the adhesive forming the adhesive layer is not particularly limited, for example, an acrylic polymer, a silicone polymer, a polyester, a polyurethane, a polyamide, a polyether, a fluorine-based polymer, or Polymers such as rubber-based polymers are used as the base polymer. In particular, an acrylic adhesive is excellent in optical transparency, and exhibits moderate wettability, cohesiveness, and adhesive properties, and is excellent in weather resistance and heat resistance.

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

For practical purposes, to prevent contamination, the exposed surface of the adhesive layer may be temporarily covered with a separator to cover it. This can prevent contact with the adhesive layer in a normal operation state. In addition to the aforementioned thickness conditions, the separator can be used: as necessary, plastic film, rubber sheet, paper, cloth, non-woven fabric, coating, etc. should be coated with a suitable release agent such as silicone-based, long-chain alkyl-based, fluorine-based, molybdenum sulfide, etc. Appropriate thin bodies such as nets, foamed sheets, metal foils, laminates thereof, and the like are appropriate ones that follow conventional techniques.

The laminated polarizing film or the laminated optical film of the present invention can be suitably used in the formation of various devices such as a liquid crystal display device and the like. The formation of the liquid crystal display device can be performed in accordance with conventional techniques. That is, a liquid crystal display device can generally be formed by appropriately combining constituent components such as a liquid crystal cell, a laminated polarizing film or a laminated optical film, and a lighting system as required, and incorporating a driving circuit, etc., but in the present invention, Except for the laminated polarizing film or laminated optical film of the invention, conventional techniques can be followed without particular limitation. Regarding the liquid crystal cell, for example, any type such as a TN type, an STN type, and a π type can be used.

The liquid crystal display device can be formed on one or both sides of a liquid crystal cell, and a laminated polarizing film or a laminated optical film is arranged, and a suitable liquid crystal display device such as a backlight element or a reflection plate is used in the lighting system. At this time, the laminated polarizing film or the laminated optical film according to the present invention may be disposed on one side or both sides of the liquid crystal cell. When a laminated polarizing film or a laminated optical film is provided on both sides, they may be the same or different. In addition, when forming a liquid crystal display device, one or more layers such as a diffusion plate, an anti-glare layer, an anti-reflection film, a protective plate, a fluorene array, a lens array sheet, a light diffusion plate, and a backlight element may be disposed at appropriate positions. And other appropriate components.

Examples

Although the embodiments of the present invention are described below, the embodiments of the present invention are not limited by them.

<Measurement of storage elastic modulus>

Regarding the adhesive layer or the adhesive layer used in Examples and Comparative Examples, the storage elastic modulus was determined by the following method.

[Measurement method of storage elastic modulus]

The storage elastic modulus was performed using a viscoelasticity spectrometer (trade name: RSA-II) manufactured by Rheometric. The measurement conditions were within a range of -50 ° C to 200 ° C at a frequency of 1 Hz, a sample thickness of 2 mm, a pressing weight of 100 g, and a heating rate of 5 ° C / min. The values at 25 ° C and 85 ° C were used as measurement values.

<Moisture permeability of transparent protective film>

The measurement of moisture permeability is measured in accordance with the moisture permeability test (cup method) according to JIS Z0208. A sample cut into a diameter of 60 mm was set in a moisture-permeable cup containing about 15 g of calcium chloride, and the weight of calcium chloride was measured before and after being placed in a thermostat at a temperature of 40 ° C and a humidity of 90% RH for 24 hours. Obtained moisture permeability (g / m ² / 24h).

<Transparent protective film>

Transparent protective film (2a): a lactone ring structure having a thickness of 50μm of the (meth) acrylic resin (moisture permeability of 96g / m ² / 24h) subjected to a corona treatment is used.

Transparent protective film (2b): A cyclic polyolefin film (Zeonor, manufactured by Zeon Corporation, Japan) with a thickness of 18 μm was used by corona treatment.

<Polyvinyl alcohol-based adhesive>

Relative to PVA-based resins containing an acetamidine (AA) group (average degree of polymerization: 1200, degree of saponification: 98.5 mol%, degree of AA group modification: 5 mol%, (shown as AA modification in Table 1) Quality PVA.)) 100 parts, at 30 ° C., 20 parts of methylolmelamine was dissolved in pure water to prepare an aqueous solution having a solid portion concentration adjusted to 0.5%. This was used as an adhesive at a temperature of 30 ° C.

<Production of ordinary polarizers>

A polyvinyl alcohol film having an average degree of polymerization of 2400, a degree of saponification of 99.9 mole%, and a thickness of 75 μm was immersed in warm water at 30 ° C. for 60 seconds to swell. Next, it was stretched to 3.5 times while dyeing in 0.3% by weight (weight ratio: iodine / potassium iodide = 0.5 / 8) in an iodine solution at 30 ° C for 1 minute. After that, the total stretching ratio was extended to 6 times while being immersed in a 4% by weight boric acid aqueous solution at 65 ° C for 0.5 minutes. After stretching, it was dried in an oven at 70 ° C. for 3 minutes to obtain a polarizer having a thickness of 26 μm.

<Production of the polarizing film (P1) shown in FIG. 2>

On both surfaces of the polarizer, the transparent protective films (2a) and (2b) were adhered while applying the polyvinyl alcohol-based adhesive, and then dried at 50 ° C for 5 minutes to prepare a polarizing film. The thickness of the adhesive layer (b1) formed on the transparent protective films (2a) and (2b) is either 0.1 μm, and the storage elastic modulus at 25 ° C is 1.5 × 10 ⁹ Pa, at 85 ° C. The storage elastic modulus is 1.0 × 10 ⁸ Pa.

<Creating a thin polarizer>

In order to make a thin polarizing film, a laminated body having a 9 μm-thick PVA layer formed on an amorphous PET substrate was firstly formed by air-assisted stretching at an extension temperature of 130 ° C, and then the extended laminated body was dyed. The colored laminated body is generated, and then stretched in boric acid water at an extension temperature of 65 ° C to produce an optical film laminated body including a 4 μm thick PVA layer (the PVA layer is integrally extended with an amorphous PET substrate, so that the total extension ratio becomes 5.94 Times). By such a two-stage extension, the PVA molecules of the PVA layer formed on the amorphous PET substrate are aligned in a higher order, so that the iodine adsorbed by the dyeing process is increased. The iodine ion complex is a highly functional polarizing film formed by high-order alignment in one direction, and an optical film laminate including a PVA layer having a thickness of 5 μm can be generated.

<Preparation of the polarizing film (P2) shown in FIG. 3>

The transparent protective film (2a) was adhered to the surface of the polarizing film of the optical film laminate while applying the polyvinyl alcohol-based adhesive, and then dried at 50 ° C for 5 minutes. The thickness of the adhesive layer (b1) formed on the transparent protective film (2a) is 1 μm, the storage elastic modulus at 25 ° C is 1.5 × 10 ⁹ Pa, and the storage elastic modulus at 85 ° C is 1.0 × 10. ⁸ Pa.

Next, the amorphous PET substrate was peeled off, and the peeling surface was coated with an activated energy ray hardening type adhesive (shown below with respect to the active energy of the low-elasticity adhesive layer (a) of Example 1 below). The same applies to the linear curing type adhesive), and the transparent protective film (2b) is adhered and then cured by ultraviolet rays to produce a polarizing film using a thin polarizing film. The thickness of the adhesive layer (b2) formed on the transparent protective film (2b) is 5 μm, the storage elastic modulus at 25 ° C is 8.0 × 10 ⁶ Pa, and the storage elastic modulus at 85 ° C is 8.0 × 10 ⁶ Pa.

<Active energy line>

Ultraviolet (Metal halide lamp enclosed with gallium) irradiation device: Fusion UV Systems, Inc. Light HAMMER 10 valve: V valve peak illuminance: 1600 mW / cm ² , cumulative exposure 1000 / mJ / cm ² (wavelength 380 ~ 440nm ) As active energy rays. In addition, the illuminance of ultraviolet rays was measured using a Sola-Check system manufactured by Solatell.

<Measurement of viscosity>

Active energy ray hardening type adhesives used in Examples and Comparative Examples or The viscosity of the adhesive (cp / 25 ° C) is a value measured by an E-type rotary viscometer. The measurement results are shown in Table 1.

Examples 1 to 4 and Comparative Example 1

(Adjustment of active energy ray-curable adhesives related to the low-elasticity adhesive layer (a))

Each component was mixed according to the mixing table described in Table 1, and it stirred at 50 degreeC for 1 hour, and obtained the active energy ray hardening type adhesive agent. The numerical values of the active energy ray-curable adhesives in the table indicate parts by weight.

(Phase retardation film)

An acrylic retardation film (ARTON, manufactured by JSR Corporation, having a thickness of 40 μm and a front retardation of 140 nm) was used.

(Manufacturing method of laminated polarizing film)

On the corona surface of the retardation film, an MCD coater (manufactured by Fuji Machinery Co., Ltd.) was used (grid shape: honeycomb shape, number of gravure roll lines: 1000 pieces / INCH, rotation speed 140% / pair line speed), and coating Table 1 The active energy ray-curable adhesive described in relation to the low-elasticity adhesive layer (a) was made into the thickness shown in Table 1.

The adhesive-coated surface of the retardation film is bonded to a polarizing film (P1) or (P2). The polarizing film (P1) is adhered on the transparent protective film (2b) side, and the polarizing film (P2) is adhered on the transparent protective film (2a) side. Then, from the bonded retardation film side, the temperature was increased to 50 ° C using an IR heater, and the aforementioned ultraviolet rays were irradiated to harden the active energy ray hardening type adhesive for the low-elasticity adhesive layer (a), and then at 70 ° C. Hot air drying was performed for 3 minutes to obtain a laminated polarizing film. The production line speed of bonding is performed at 15m / min.

Comparative Examples 2, 3

<Preparation of (meth) acrylic polymer>

In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler, 92 parts of butyl acrylate and N-acrylfluorenyl were fed. 5 parts of phthaloline, 2.9 parts of acrylic acid, 0.1 parts of 2-hydroxyethyl acrylate, 0.1 parts by weight of 2,2'-azobisisobutyronitrile as polymerization initiators, and 200 parts by weight of ethyl acetate. Nitrogen was introduced with stirring while nitrogen substitution was performed, and the temperature of the liquid in the flask was maintained at about 55 ° C. to perform a polymerization reaction for 8 hours to prepare an acrylic polymer solution. The weight average molecular weight of the acrylic polymer was 2.2 million.

<Creation of a polarizing film with an adhesive layer>

A polyisocyanate-based cross-linking agent composed of toluene diisocyanate trimethylol propane adduct (Japanese polyaminomethyl) was prepared based on 100 parts of the solid portion of the acrylic polymer solution obtained as described above. Acrylic adhesive solution made from 0.2 parts of Coronate L) manufactured by Ester Industry Co., Ltd. Next, the acrylic adhesive solution was applied onto one side of a silicone-treated polyethylene terephthalate (PET) film (manufactured by Mitsubishi Chemical Polyester Film Co., Ltd., thickness: 38 μm) and allowed to dry. The thickness of the subsequent adhesive layer was as shown in Table 1 (5.5 μm in Comparative Example 2; 4.0 μm in Comparative Example 3), and dried at 150 ° C. for 3 minutes to form an adhesive layer.

<Preparation of Laminated Polarizing Film>

The aforementioned adhesive layer is adhered to the polarizing film (P1) or (P2). The adhesive layer is adhered to the transparent protective film (2b) side in the polarizing film (P1), and the adhesive layer is adhered to the transparent protective film (2a) side in the polarizing film (P2). after that, The PET film was peeled off and the retardation film was bonded to obtain a laminated polarizing film.

The following evaluation was performed about the laminated polarizing film obtained by each case. The results are shown in Table 1.

<Shock resistance>

An adhesive layer is laminated on the retardation film surface of the laminated polarizing film, and cut into a rectangle with a length of 50 mm in the extension direction of the polarizer and 100 mm in the vertical direction. The aforementioned laminated polarizing film was laminated on a glass plate having a thickness of 0.5 mm, a length of 120 mm, and a width of 60 mm to prepare a sample. Furthermore, in order to prevent damage, cellophane tape was stuck on the entire surface of the back surface of the glass plate.

The prepared sample dropped naturally from a height of 1 m. The end peeling state after repeating this drop 100 times was visually observed.

○: No peeling was confirmed.

Δ: The peeling from the end is less than 1 mm.

×: Peeling from the end is 1 mm or more.

<Thermal buckling property>

An adhesive layer is laminated on the retardation film surface of the laminated polarizing film, and cut into a rectangle having a length of 200 mm in the extension direction of the polarizer and 400 mm in the vertical direction. On both sides of the liquid crystal cell (take out and use the liquid crystal cell from "32-inch LCD TV BRAVIA (registered trademark) KDL-32F1 made by Sony Corporation"), the foregoing polarizing film is laminated with the aforementioned adhesive to make it orthogonal. Nico otoscope is used to create a liquid crystal panel. The following tests were performed on this liquid crystal panel.

1: Heating test (12 hours at 85 ° C)

2: -40 ° C 85 ° C heating cycle test, 100 cycles

After the test, the liquid crystal panel was visually observed and the stripe unevenness was evaluated based on the following criteria.

○: No occurrence of stripe unevenness was observed.

×: Stripes were uneven.

<Peeling force: forced peeling>

The laminated polarizing film is cut out to a size parallel to the extension direction of the polarizer by 200 mm and a straight direction of 20 mm. After cutting out a cut between the polarizing film and the retardation film with a cutter, the laminated polarizing film is bonded to the glass plate. The polarizing film and the retardation film were peeled by a Tensilon tensile tester at a peeling speed of 500 mm / min in a 90-degree direction, and the peeling strength was measured. The infrared absorption spectrum of the peeled surface after peeling was measured by the ATR method, and the peeling interface was evaluated based on the following criteria.

1: The glue of the low-elasticity adhesive layer (a) fails.

2: The cementation of the retardation film fails.

In the aforementioned standard, 2 indicates that the adhesive force is not less than the film cohesive force, and thus indicates that the adhesive force is very excellent. On the other hand, 1 means that the bonding force at the interface of the polarizing film / adhesive layer / retardation film is insufficient (adhesive force difference).

<Peelability: Peeling Force>

The laminated polarizing film was cut out to a size parallel to the extension direction of the polarizer of 200 mm and a straight direction of 15 mm. After cutting out a cut between the polarizing film and the retardation film with a cutter, the laminated polarizing film was bonded to a glass plate. The polarizing film and the retardation film were peeled by a Tensilon tensile tester at a peeling speed of 300 mm / min in a 90-degree direction, and the peeling strength (N / 15 mm) was measured.

The adhesive layers of Comparative Examples 2 and 3 in Table 1 and the low-elasticity adhesive layer (a) are compared. For reference, the ratio of the monomer components constituting the acrylic polymer forming the adhesive is described.

(A): Multifunctional radical polymerizable compound

Aronix M-270 represents polypropylene glycol diacrylate (manufactured by Toa Kosei Co., Ltd.).

TPGDA: stands for tripropylene glycol diacrylate.

Light Acrylate 9EG-A represents a glycol (average value of 9 added moles) diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.).

(B): Alkyl (meth) acrylate having an alkyl group having 2 to 12 carbons means n-butyl acrylate; (C): (meth) acrylate having a hydroxyl group 2HEA means 2-hydroxyethyl acrylic acid Ester; 4HBA means 4-hydroxybutyl acrylate; PLACCEL FA1DDM means 2HEA caprolactone 1 mol adduct (manufactured by Daicel).

(Others): radical polymerizable compounds other than the foregoing

HEAA means hydroxyethyl acrylamide (manufactured by Xingren Company); ACMO means acryl amidino Porphyrin (produced by Xingren Company).

(E): an acrylic oligomer obtained by polymerizing a (meth) acrylic monomer

UP-1190 represents an acrylic oligomer (ARUFON UP-1190, manufactured by Toa Kosei Co., Ltd.) obtained by polymerizing a (meth) acrylic monomer.

(F): radical polymerizable compound having a living methylene group

AAEM stands for 2-Acetylacetoxyethyl methacrylate (Japan Manufactured by Synthetic Chemical Co., Ltd.).

(G): Free radical polymerization initiator with hydrogen abstraction

KAYACURE DETX-S represents a radical polymerization initiator (diethyl 9-oxysulfur , KAYACURE DETX-S, manufactured by Nippon Kayaku Co., Ltd.).

(Photopolymerization initiator: others) (compound represented by general formula (2))

IRGACURE 907 means 2-methyl-1- (4-methylthiophenyl) -2- Porphyrin-1-one (IRGACURE 907, manufactured by BASF).

Claims (29)

A laminated polarizing film is characterized in that it is a laminated polarizing film formed by laminating a polarizing film and an optical film other than a polarizer by a low-elasticity adhesive layer (a), wherein the polarizing film is passed through an adhesive layer (b ) A transparent protective film is laminated on at least one side of the polarizer, and the above-mentioned low-elastic adhesive layer (a) is laminated on the transparent protective film, and the low-elastic adhesive layer (a) has a storage elastic mold at 25 ° C. The number is 3.0 × 10 ⁵ to 1.0 × 10 ⁸ Pa, and the thickness of the aforementioned low elastic adhesive layer (a) is 0.1 to 5 μm. The laminated polarizing film according to claim 1, wherein the optical film is a retardation film. The laminated polarizing film according to claim 1, wherein the low-elasticity adhesive layer (a) is a hardened material layer obtained by irradiating an active energy ray-curable adhesive with an active energy ray. For example, the laminated polarizing film of claim 3, wherein the aforementioned active energy ray-curable adhesive is a liquid substance that does not substantially contain an organic solvent and has a viscosity of 1 to 100 cp / 25 ° C. The laminated polarizing film according to claim 3, wherein the active energy ray-curable adhesive contains a radical polymerizable compound as a curable component. The laminated polarizing film according to claim 5, wherein the radical polymerizable compound includes a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound (A). The laminated polarizing film according to claim 6, wherein when the total amount of the radical polymerizable compound is 100% by weight, the proportion of the polyfunctional radical polymerizable compound (A) is 1 to 65% by weight. The laminated polarizing film according to claim 6, wherein the polyfunctional radically polymerizable compound (A) is a bifunctional (meth) acrylate having a weight average molecular weight of 200 to 4000. The laminated polarizing film according to claim 6, wherein the radical polymerizable compound includes an alkyl (meth) acrylate (B) having an alkyl group having 2 to 18 carbon atoms. The laminated polarizing film according to claim 6, wherein the radical polymerizable compound contains a (meth) acrylate (C) having a hydroxyl group. The laminated polarizing film according to claim 10, wherein the (meth) acrylate (C) having a hydroxyl group is a hydroxyl-containing monofunctional (meth) acrylate having a weight average molecular weight of 160 to 3000. The laminated polarizing film according to claim 3, wherein the active energy ray-curable adhesive includes a silane coupling agent (D). The laminated polarizing film according to claim 12, wherein the silane coupling agent (D) is a silane coupling agent having no radical polymerizable functional group. The laminated polarizing film according to claim 3, wherein the active energy ray-curable adhesive includes an acrylic oligomer (E) obtained by polymerizing a (meth) acrylic monomer. The laminated polarizing film according to claim 3, wherein the active energy ray-curable adhesive includes a radical polymerizable compound (F) having an active methylene group, and a radical polymerization initiator (G) having a hydrogen abstraction effect. The laminated polarizing film according to claim 15, wherein the aforementioned active methylene group is acetamidine. The laminated polarizing film according to claim 15, wherein the radically polymerizable compound (F) having an active methylene group is acetoacetoxyalkyl (meth) acrylate. The laminated polarizing film according to claim 15, wherein the aforementioned radical polymerization initiator (G) is 9-oxysulfur It is a radical polymerization initiator. For example, the laminated polarizing film of claim 1, wherein the adhesive layer (b) is an adhesive having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness of 0.03 to 3 μm . Layer (b1). The laminated polarizing film according to claim 1, wherein the polarizing film is provided with the transparent protective film on both sides of the polarizer through the adhesive layer (b), and any one of the adhesive layer (b) Both are adhesive layers (b1) having a storage elastic modulus at 85 ° C. of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness satisfying 0.03 to 3 μm . The laminated polarizing film according to claim 1, wherein the polarizing film is provided with the transparent protective film on both sides of the polarizer through the adhesive layer (b), and the adhesive layer (b) on one side is provided. The adhesive layer (b1) with a storage elastic modulus at 85 ° C of 1.0 × 10 ⁶ to 1.0 × 10 ¹⁰ Pa and a thickness of 0.03 to 3 μm , and the aforementioned adhesive layer (b) on the other side The adhesive layer (b2) having a storage elastic modulus at 85 ° C of 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa and a thickness satisfying 0.1 to 25 μm . For example, the laminated polarizing film of claim 1, wherein the thickness of the aforementioned polarizer is 1 to 10 μm . If the laminated polarizing film according to claim 1, the transparent protective film on at least one side of the transparent protective film is a retardation film. For example, in the laminated polarizing film according to claim 1, when the polarizing film and the optical film are forcibly peeled off, the low-elasticity adhesive layer (a) may fail in a cement. The laminated polarizing film according to any one of claims 1 to 24, wherein a peeling force when forcibly peeling the polarizing film and the optical film is 1 to 5 N / 15 mm. A manufacturing method of a laminated polarizing film, which is characterized in that it is a manufacturing method of a laminated polarizing film according to any one of claims 1 to 25, and the manufacturing method includes the following steps: a coating step, which is a step in the aforementioned polarizing film. Laminate the transparent protective film on the side of the low-elasticity adhesive layer (a) and at least one side of the optical film, and apply the active energy ray-hardening type adhesive agent to form the low-elasticity adhesive layer (a); an adhesion step, which is adhesion The polarizing film and the optical film; and a step of adhering the polarizing film and the optical film by a low-elasticity adhesive layer (a), wherein the low-elasticity adhesive layer (a) is by irradiating the activity The energy ray is obtained by hardening the active energy ray-curable adhesive. For example, the manufacturing method of the polarizing film of claim 26, wherein the ratio of the integrated illuminance of the aforementioned active energy ray in the wavelength range of 380 to 440 nm to the integrated illuminance in the wavelength range of 250 to 370 nm is 100: 0 to 100: 50. A laminated optical film, characterized in that at least one laminated polarizing film according to any one of claims 1 to 25 is laminated. An image display device characterized by using a laminated polarizing film according to any one of claims 1 to 25 or a laminated optical film according to claim 28.