KR20180088277A - Optical laminate and image display device - Google Patents

Abstract

Provided is an optical laminate in which mark formation on a polarizing plate is suppressed when fixed on an adsorption table. Moreover, provided is an image display device. To this end, the optical laminate includes a surface protective film, a first adhesive layer, the polarizing plate, a second adhesive layer, and a release film in order. A is a product obtained by multiplying thickness and tensile elasticity modulus of the surface protective film, B is a product obtained by multiplying thickness and tensile elasticity modulus of the polarizing plate, and C is the product obtained by multiplying thickness and tensile elasticity modulus of the release film, wherein each satisfies the following, A > B + C.

Description

Technical Field [0001] The present invention relates to an optical laminate and an image display device,

The present invention relates to an optical laminate and an image display apparatus.

The polarizing plate is bonded to an optical member such as a liquid crystal cell and is widely used in an image display apparatus such as a liquid crystal display apparatus. In the step of bonding the polarizing plate to an optical member such as a liquid crystal cell, for example, an optical laminate having a surface protective film, a polarizing plate and a peeling film in this order is fixed on an adsorption table having an adsorption pad, And the polarizing plate is peeled off and bonded to the optical member.

Description of the Related Art [0002] In recent years, there has been known a technique of obtaining a thin polarizing plate including a polarizer of a thin shape (for example, 12 탆 or less) along with a demand for thinning of an optical member used in an image display apparatus. However, the thin polarizing plate has no elasticity, and there is a problem such that curling occurs or fusion failure occurs in a process of adhering to an optical member such as a liquid crystal cell. Patent Document 1 discloses a surface protective film having a surface protective film, a thin polarizing plate and a peeling film and having a ratio (T2 / T1) of the thickness (T2) of the surface protective film to the thickness T1 of the polarizing plate within a range of 0.8 to 4 A polarizing plate having a protective film is described. The polarizing plate with the surface protective film of Patent Document 1 has a thickness and includes a surface protective film having elasticity, so that the above problem caused by the thinning of the polarizing plate can be solved.

Japanese Laid-Open Patent Publication No. 2016-118771

However, in the conventional optical laminate described in Patent Document 1 and the like, there is a problem that, when the release film is fixed on the adsorption table in the step of peeling, there is a trace of the adsorption pad on the polarizer.

The main object of the present invention is to provide an image display apparatus provided with an optical laminate and a polarizing plate of the optical laminate suppressed from leaving traces on the polarizer plate when fixed to the adsorption table .

The optical laminate of the present invention has a surface protective film, a first pressure-sensitive adhesive layer, a polarizing plate, a second pressure-sensitive adhesive layer and a release film in this order, and the product of the tensile modulus and the thickness of the surface- B is the product of the tensile modulus of elasticity of the polarizing plate and the thickness, and C is the product of the tensile elastic modulus and the thickness of the release film.

In one embodiment, Y <X is satisfied when the instrument peeling force of the surface protective film is X (N / 50 mm) and the instrument peeling force of the release film is Y (N / 50 mm) , More preferably X - Y > 0.1.

In one embodiment, the total thickness of the surface protective film and the first pressure sensitive adhesive layer is 75 占 퐉 or more, and the thickness of the release film is 38 占 퐉 or less.

In one embodiment, the polarizing plate has a polarizer and a protective layer laminated on the surface protective film side of the polarizer, and the thickness of the polarizer is 12 占 퐉 or less.

According to another aspect of the present invention, an image display apparatus is provided. This image display apparatus has the polarizing plate of the optical laminate and the optical member in which the polarizing plate is bonded via the second pressure-sensitive adhesive layer.

According to the present invention, it is possible to provide an image display apparatus provided with an optical laminate in which no marks are left on the polarizer when fixed to the adsorption table, and a polarizer of the optical laminate.

1 is a schematic sectional view of an optical laminate according to an embodiment of the present invention.
2 is a schematic cross-sectional view showing a state in which the release film is peeled off from the optical laminate.
3 is a schematic cross-sectional view showing a state in which the surface protective film is peeled off from the optical laminate.
4 is a schematic cross-sectional view of an optical laminate according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

A. Overall construction of optical laminate

1 is a schematic sectional view of an optical laminate according to an embodiment of the present invention. The optical laminate 100 has a surface protective film 10, a first pressure sensitive adhesive layer 20, a polarizing plate 30, a second pressure sensitive adhesive layer 40 and a release film 50 in this order . The polarizing plate 30 has the first protective layer 32 laminated on the side of the surface protective film 10 of the polarizer 31 and the polarizer 31. In this embodiment, The thickness of the polarizer 31 is typically 12 占 퐉 or less. The total thickness of the surface protective film 10 and the first pressure sensitive adhesive layer 20 is preferably 75 占 퐉 or more and the thickness of the release film 50 is preferably 38 占 퐉 or less. 2 is a schematic cross-sectional view of an optical laminate according to another embodiment of the present invention. The polarizing plate 30 includes a first protective layer 32 laminated on the side of the surface protective film 10 of the polarizer 31 and the polarizer 31 and a peeling film 50 of the polarizer 31, And a second protective layer 33 laminated on the second protective layer 33 side. Like the optical laminate 101 of the present embodiment, the polarizing plate 30 may have a protective layer on both sides of the polarizer 31. [ The optical laminate 100 and the optical laminate 101 are formed such that the product of the tensile modulus of elasticity of the surface protective film 10 and the thickness is A and the product of the tensile modulus of elasticity of the polarizer 30 and the thickness is B, 50) satisfies A> B + C, where C is the product of the tensile modulus and thickness. Such an optical laminate can be suppressed from remaining on the polarizing plate when it is fixed to the adsorption table. The product B of the tensile modulus of elasticity of the polarizer 30 and the thickness of the polarizer 30 is calculated by multiplying the product B1 of the tensile modulus of elasticity of the polarizer 31 and the thickness B1 by the product B2 of the tensile modulus and thickness of the first protective layer 32, Is calculated by the product of the tensile modulus of elasticity of the layer 33 and the thickness B3 (when the second protective layer is present).

As a result of intensive investigations, the inventors of the present invention have found that the above optical laminate suppresses the remnant of the polarizing plate, and when the release film is peeled off from the end, the polarizing plate is peeled from the surface protective film interface I found a new assignment to throw away. In order to solve the above problem, in one embodiment, the optical laminated body 100 and the optical laminated body 101 are formed such that the instrument peeling force of the surface protective film 10 is X (N / 50 mm) When the separating force of the peeling film 50 is Y (N / 50 mm), preferably satisfies Y <X, more preferably satisfies X - Y> 0.1. In general, when the film is peeled from the end portion at a constant peeling rate, the peeling force of the film increases with the peeling length immediately after the peeling start, decreases with the peak, and stabilizes at a constant value after a predetermined time has elapsed. In the present specification, the instrument peeling force of the film means the peak value (maximum value) of the peeling force immediately after the peeling is started, and the normal peeling force of the film means a stable peeling force after a predetermined time from the peeling start . The optical laminate 100 (and the optical laminate 101) is peeled off the release film 50 as shown in Fig. 3, and the polarizer 30 is separated from the other optical member 30 via the second pressure- (For example, a liquid crystal cell). For example, when an optical laminate having a surface protective film with a high tensile modulus or an optical laminate in which the instrument peel strength of the peel film is larger than the instrument peel strength of the surface protective film is used for peeling the peel film 50 from the end The surface protective film 10 and the first pressure sensitive adhesive layer 20 are peeled from the polarizing plate 30 without peeling the peeling film 50 as shown in Fig. 4 (the peeling film 50 is peeled off from the polarizing plate 30 ) Of the first pressure sensitive adhesive layer 20), so that peeling failure may occur. On the other hand, in the optical laminate 100 of the embodiment, the instrument peeling force Y of the peeling film 50 is smaller than the instrument peeling force X of the surface protective film 10, as described above. 3, the surface protective film 10 and the first pressure-sensitive adhesive layer 20 are not peeled off from the polarizing plate 30, and the peeling film 50 can be peeled from the second pressure-sensitive adhesive layer 40 .

The optical laminated body 100 and the optical laminated body 101 may be in the form of a single sheet or a laminate.

B. Surface Protective Film

The surface protective film is laminated on one surface of the polarizing plate with the first pressure sensitive adhesive layer interposed therebetween, and can function as a protective film of the polarizing plate. The surface protective film is typically a transparent film having isotropy. The surface protective film can be peeled off at any appropriate point after the polarizing plate is bonded to the other optical member via the second pressure-sensitive adhesive layer.

The thickness of the surface protective film is preferably 25 탆 to 250 탆, more preferably 50 탆 to 200 탆, and particularly preferably 70 탆 to 150 탆. By using a surface protective film having sufficient thickness and rigidity, it is possible to suppress the occurrence of curling in the step of bonding the polarizing plate to an optical member such as a liquid crystal cell, and further, while conveying each layer constituting the optical laminate In the case of lamination, the transportability of the laminate is improved, and as a result, the production efficiency of the optical laminate can be improved.

The tensile modulus of elasticity of the surface protective film is preferably 2000 MPa to 5000 MPa, more preferably 2500 MPa to 4500 MPa, and particularly preferably 3000 MPa to 4000 MPa.

Examples of the material constituting the surface protective film include a polyester resin such as a polyethylene terephthalate film, a cellulose resin, an acetate resin, a polyether sulfone resin, a polycarbonate resin, a polyamide resin, Based resin, a mid-based resin, a polyolefin-based resin, and an acrylic-based resin. Among these, a polyester resin is preferable.

C. polarizer

The polarizing plate includes at least a polarizer. Preferably, the polarizing plate has a protective layer on at least one side of the polarizer.

C-1. Polarizer

The thickness of the polarizer is preferably 12 占 퐉 or less, more preferably 1 占 퐉 to 10 占 퐉, and still more preferably 3 占 퐉 to 8 占 퐉, as described above. The tensile modulus of the polarizer is preferably 300 MPa to 1000 MPa, more preferably 400 MPa to 900 MPa, and particularly preferably 500 MPa to 800 MPa.

The polarizer preferably exhibits absorption dichroism at any wavelength from 380 nm to 780 nm. In one embodiment, the transmittance (also referred to as a unit transmittance) of the wavelength of 589 nm of the polarizer is preferably 42.0% to 46.0%, and more preferably 44.5% to 46.0%. The degree of polarization of the polarizer is preferably 97.0% or more, more preferably 99.0% or more, and further preferably 99.9% or more. In another embodiment, the polarizer is preferably configured so that when the transmittance T is less than 42.3%, the polarization degree P is larger than - (10 ^{0.929T-42.4-1} ) 100% and the transmittance T is 42.3% P is more than 99.9%.

As the polarizer, any suitable polarizer may be employed. For example, the resin film forming the polarizer may be a single-layer resin film or a laminate of two or more layers.

As specific examples of the polarizer composed of the single-layer resin film, a hydrophilic polymer film such as a polyvinyl alcohol (PVA) film, a partially formalized PVA film, and an ethylene / vinyl acetate copolymerization system partially saponified film, Dyes such as dyestuffs, and polyene-based oriented films such as dehydrated PVA and dehydrochlorinated polyvinyl chloride films. Preferably, a polarizer obtained by dying a PVA-based film with iodine and uniaxially stretching is used from the viewpoint of excellent optical characteristics.

The dyeing by iodine is carried out, for example, by immersing a PVA-based film in an iodine aqueous solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. The stretching may be performed after the dyeing treatment, or may be performed while dyeing. Further, it may be dyed after stretching. If necessary, swelling treatment, crosslinking treatment, washing treatment, drying treatment and the like are performed on the PVA film. For example, by dipping the PVA film in water before dying, the PVA film can be cleaned, and the PVA film can be swollen, thereby preventing uneven dyeing.

Specific examples of the polarizer obtained by using the laminate include a laminate of a resin substrate and a PVA resin layer (PVA resin film) laminated on the resin substrate, or a laminate of a resin substrate and a PVA resin layer And a polarizer obtained by using a laminate of A polarizer obtained by using a laminate of a resin substrate and a PVA resin layer formed on the resin substrate can be produced by, for example, applying a PVA resin solution to a resin substrate and drying to form a PVA resin layer on the resin substrate To obtain a laminate of a resin substrate and a PVA-based resin layer; And stretching and dyeing the laminate to prepare a PVA resin layer as a polarizer. In the present embodiment, the stretching typically involves immersing the laminate in an aqueous solution of boric acid and stretching. Further, the stretching may further include, if necessary, air-stretching the laminate at a high temperature (for example, 95 ° C or more) before stretching in an aqueous solution of boric acid. Details of the method for producing such a polarizer are described, for example, in Japanese Laid-Open Patent Publication No. 2012-73580. This publication is incorporated herein by reference in its entirety. The laminate of the obtained resin substrate / polarizer may be used as is (that is, the resin substrate may be a protective layer of a polarizer).

C-2. Protective layer

The protective layers (the first protective layer and the second protective layer) are formed of any suitable film that can be used as a protective layer of the polarizer. Specific examples of the material constituting the main component of the film include cellulose-based resins such as triacetylcellulose (TAC), polyester-based resins, polyvinyl alcohol-based resins, polycarbonate-based resins, polyamide-based resins, polyimide- (Meth) acrylate, acetate and the like, and the like can be given as examples of the transparent resin such as polyolefin resin, polystyrene resin, polynorbornene resin, polyolefin resin, Further, thermosetting resins such as (meth) acrylic resins, urethane resins, (meth) acrylurethane resins, epoxy resins and silicon resins, and ultraviolet curable resins may also be used. In addition, for example, glassy polymers such as siloxane-based polymers may be mentioned. A polymer film described in Japanese Patent Application Laid-Open No. 2001-343529 (WO01 / 37007) may also be used. As a material of this film, for example, a resin composition containing a thermoplastic resin having a substituted or unsubstituted imide group in a side chain and a thermoplastic resin having a phenyl group and a substituted or unsubstituted phenyl group and a nitrile group in the side chain can be used. For example, a resin composition having an alternating copolymer composed of isobutene and N-methylmaleimide and an acrylonitrile-styrene copolymer may be mentioned. The polymer film may be, for example, an extrusion molded article of the resin composition. The constituent material of the first protective layer and the constituent material of the second protective layer may be the same or different.

The protective layer may be subjected to surface treatment such as hard coat treatment, antireflection treatment, anti-sticking treatment, and antiglare treatment, if necessary.

The thickness of the protective layer is typically 5 mm or less, preferably 1 mm or less, more preferably 1 to 500 占 퐉, and further preferably 5 to 150 占 퐉. When the surface treatment is carried out, the thickness of the protective layer includes the thickness of the surface treatment layer. The thickness of the first protective layer and the thickness of the second protective layer may be the same or different. The tensile modulus of elasticity of the protective film constituting the protective layer is preferably 1500 MPa to 3800 MPa, more preferably 2000 MPa to 3300 MPa, and particularly preferably 2300 MPa to 3000 MPa.

D. Peeling film

The release film is laminated on the opposite side to the surface protective film of the polarizing plate with the second pressure sensitive adhesive layer interposed therebetween, and is peeled and removed when the polarizing plate is bonded to the other optical member via the second pressure sensitive adhesive layer.

The thickness of the release film is preferably 5 탆 to 200 탆, more preferably 10 탆 to 100 탆, and still more preferably 20 to 50 탆. The tensile modulus of elasticity of the release film is preferably 2000 MPa to 5000 MPa, more preferably 2500 MPa to 4500 MPa, and particularly preferably 3000 MPa to 4000 MPa.

The release film is typically composed of a plastic film and a release imparting layer formed on one side of the plastic film. Examples of the plastic film include a polyester film such as a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film and a polyethylene terephthalate film, A polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film. Among these, a polyester film is preferable. The release-imparting layer may be a layer coated with a suitable releasing agent such as a silicone system, a long-chain alkyl system, or a fluorine system.

The peeling film is applied to the polarizing plate by applying a pressure-sensitive adhesive constituting the second pressure-sensitive adhesive layer on the peeling-imparting layer, drying it.

E. Pressure-sensitive adhesive layer

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, any suitable pressure-sensitive adhesive can be used. Examples of such a pressure-sensitive adhesive include rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, silicone pressure-sensitive adhesives, urethane pressure-sensitive adhesives, vinyl alkyl ether pressure-sensitive adhesives, polyvinyl alcohol pressure-sensitive adhesives, polyvinylpyrrolidone pressure-sensitive adhesives, polyacrylamide pressure-sensitive adhesives, and cellulosic pressure- have. Among these pressure-sensitive adhesives, those having excellent optical transparency, suitably exhibiting wettability, cohesiveness and adhesiveness with adhesiveness, and excellent weather resistance and heat resistance are preferably used. An acrylic pressure-sensitive adhesive is preferably used to exhibit such characteristics.

The thickness of the pressure-sensitive adhesive layer is preferably 7 占 퐉 to 30 占 퐉, and more preferably 10 占 퐉 to 25 占 퐉. The thickness of the first pressure sensitive adhesive layer and the thickness of the second pressure sensitive adhesive layer may be the same or different.

F. Image display device

The optical laminate described in the items A to E can be used when a polarizing plate is attached to an optical member included in an image display device such as a liquid crystal display device and an organic EL display device. Therefore, the optical laminate of the present invention includes the image display apparatus using the polarizing plate. The image display apparatus of the present invention includes a polarizing plate of the optical laminate of the present invention and an optical member in which a polarizing plate is bonded via a second pressure-sensitive adhesive layer.

Example

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples. The measuring method and the evaluation method of each characteristic are as follows.

(1) Thickness

And measurement was performed using a digital micrometer (KC-351C manufactured by Anritsu).

(2) Tensile modulus

The film or the polarizing plate to be measured was formed into a tensile test dumbbell having a parallel portion width of 10 mm and a length of 40 mm on the basis of JIS K6734: 2000 and subjected to a tensile test according to JIS K7161: 1994 to obtain a tensile modulus .

(3) Normal peel force of the surface protective film

The long side of the elongated optical laminate was cut into a size of 50 mm x 100 mm so that the long side of the optical laminate corresponded to the short side of the sample for measurement. The release film was peeled off from the sample for measurement, and the pressure-sensitive adhesive layer on the release surface was bonded to a peel-off jig.

Subsequently, the polarizing plate interface and the first pressure-sensitive adhesive layer were peeled from the short side of the sample for measurement, and the surface protective film and the first pressure-sensitive adhesive layer were chucked and tensile was measured using a tensile tester to measure the peeling force (N / 50 mm) (Tensile direction: 180 DEG with respect to the surface of the optical laminate, tensile rate: 300 mm / min). The peeling force was measured for five measurement samples and the average value of the measured values in each measurement sample was adopted as the normal peeling force of the surface protective film.

(4) Gauge peel force of surface protective film

The long side of the elongated optical laminate was cut into a size of 50 mm x 100 mm so that the long side of the optical laminate corresponded to the short side of the sample for measurement. The release film was peeled off from the sample for measurement, and the pressure-sensitive adhesive layer on the release surface was bonded to a peel-off jig.

Subsequently, a 19 mm wide polyester adhesive tape (product name: "No.31B", manufactured by Nitto Corporation) was placed on the short side of the sample for measurement (side corresponding to the long side of the optical laminate) And a polyester base adhesive tape (product name: "No.343B", manufactured by Nitto Corporation) was applied to the above-mentioned polyester adhesive tape.

Subsequently, the above polyester base adhesive tape was chucked and subjected to tensile test using a tensile tester to measure peeling force (N / 50 mm) (tensile direction: 90 DEG to the surface of the optical laminate, tensile rate: 300 mm / min, and tensile distance of 60 mm), and the peak value (maximum value) of the peeling force was defined as the "peel strength (N / 50 mm)" of the surface protective film. The instrument peeling force was measured for five measurement samples and the average value of the measurement values in each measurement sample was adopted as the instrument peeling force of the surface protective film. In the measurement of the instrument peeling force of the surface protective film, the surface protective film is peeled off (the surface protective film and the first pressure sensitive adhesive layer are peeled from the polarizing plate) as a peeling interface between the first pressure sensitive adhesive layer and the polarizing plate.

(5) Normal peeling force of peeling film

The long side of the elongated optical laminate was cut into a size of 50 mm x 100 mm so that the long side of the optical laminate corresponded to the short side of the sample for measurement. A sample for measurement was bonded to a peeling jig on a flat plate via an acrylic pressure-sensitive adhesive with the surface protective film side facing downward.

Then, the peeling film interface and the second pressure-sensitive adhesive layer were peeled from the short side of the sample for measurement, and the peeling film was chucked and stretched using a tensile tester to measure the peeling force (N / 50 mm) : 180 DEG with respect to the surface of the optical laminate, tensile rate: 300 mm / min). The peeling force was measured for five measurement samples, and the average value of the measured values in each measurement sample was adopted as a normal peeling force of the peeled film.

(6) Detaching force of peeling film

The long side of the elongated optical laminate was cut into a size of 50 mm x 100 mm so that the long side of the optical laminate corresponded to the short side of the sample for measurement. A sample for measurement was bonded to a peeling jig on a flat plate via an acrylic pressure-sensitive adhesive with the surface protective film side facing downward.

Subsequently, a 19 mm wide polyester adhesive tape (product name: "No.31B", manufactured by Nitto Corporation) was placed on the short side of the sample for measurement (side corresponding to the long side of the optical laminate) And the polyester base adhesive tape (product name: "No.343B", manufactured by Nitto Corporation) was applied to the above polyester adhesive tape.

Subsequently, the above polyester base adhesive tape was chucked and subjected to tensile test using a tensile tester to measure peeling force (N / 50 mm) (tensile direction: 90 DEG to the surface of the optical laminate, tensile rate: 300 mm / min, tensile distance: 60 mm), and the peak value (maximum value) of the peeling force was taken as the "peeling force (N / 50 mm)" of the peeled film. The instrument peeling force was measured for five measurement samples, and the average value of the measurement values in each measurement sample was adopted as the instrument peeling force of the peeling film.

(7) Peeling test of peeling film

The elongated optical laminate was cut into a size of 1215 mm x 684 mm to prepare a sample for peeling test. The sample for peeling test was placed on the adsorption table having the adsorption pad with the surface protective film side down and fixed. Then, the peeling film was peeled off by peeling the peeling roll having a diameter of 20 mm against the peaks of the sample for peeling test and rotating the peeling roll (peeling direction: 180 占 with respect to the surface of the optical stacked body, 45 DEG with respect to the short side, peeling speed: 300 mm / min).

In the case where the polarizing plate was not peeled from the surface protective film at the time of peeling off the peeling film, peeling succeeded. In the case where the peeling film was peeled off, peeling failure occurred when the polarizing plate peeled from the surface protective film.

The peeling films were peeled from the samples for ten peeling tests, and the peeling properties of the peeling films were evaluated according to the following criteria.

◎ ... The peeling test was successful for 90% or more peel test samples.

○ ... Peeling success was 60% or more and less than 90% for the peel test sample.

△ ... The peeling success was 30% or more and less than 60% for the peel test sample.

× ... The peeling test was successful for less than 30% peel test sample.

Further, the optical laminate after peeling off the release film was bonded to the liquid crystal cell via the second pressure-sensitive adhesive layer using a bonding roll. Then, the surface protective film was peeled off, and the appearance of the polarizing plate was inspected. Ten samples were visually inspected and evaluated for good or bad appearance on the basis of the following criteria.

○ ... There is no adsorption on the polarizing plate by the adsorption pad.

× ... Adsorption marks due to adsorption pads on the polarizer.

&Lt; Preparation Example 1 &

A polyethylene terephthalate film (MRF38CK, manufactured by Mitsubishi Plastics Co., Ltd.) having a thickness of about 550 占 퐉 was stretched 3.7 times in the longitudinal direction at 85 占 폚, stretched 3.9 times in the transverse direction at 100 占 폚 and heat-treated at 210 占 폚, To give a biaxially stretched polyester film.

A releasing agent comprising the releasing agent composition A shown below was applied to the surface of the biaxially oriented polyester film by a reverse gravure coating method so that the coating amount (after drying) became 0.12 g / m 2 and dried to obtain a peeling-treated To obtain a conventional release film A (thickness 38 占 퐉, tensile elastic modulus 3500 MPa).

(Release agent composition A)

A1: 24 parts by weight of a curing-type silicone resin (molecular weight: 200,000) represented by the general formula (I) having a ratio of methyl group and hexenyl group to phenyl group of 100:

[Chemical Formula 1]

A2: 33 parts by weight of a curing-type silicone resin (molecular weight: 200,000) represented by the general formula (II) wherein the ratio of the methyl group and the vinyl group is 100:

(2)

A3: 8 parts by weight of a curing-type silicone resin (molecular weight: 200,000) represented by the general formula (III) wherein the ratio of the methyl group and the hydrosilyl group is 100:

(3)

A4: 33 parts by weight of a curable silicone resin (molecular weight: 200,000) of the above-mentioned general formula (III) in which the ratio of the methyl group and the hydrosilyl group was 100: 0.4

B1: 1 part by weight of an unreactive silicone resin (molecular weight: 80000) represented by the general formula (IV)

[Chemical Formula 4]

C1: 1 part by weight of an addition type platinum catalyst (PL-50T: Shin-Etsu Chemical Co., Ltd.)

MEK / toluene mixed solvent (mixing ratio is 1: 1)

&Lt; Preparation Example 2 &

(Thickness: 25 占 퐉; tensile modulus: 3500 占 퐉) having a thickness of 25 占 퐉 and peeled with a silicone-based releasing agent in the same manner as in Production Example 1, except that the stretching magnification of the polyethylene terephthalate film was changed to 5.1 times in the longitudinal direction and 5.3 times in the transverse direction. MPa).

&Lt; Preparation Example 3 &

(Thickness: 38 mu m, tensile elastic modulus: 3500 MPa) having been stripped with a silicone-based stripper was obtained in the same manner as in Production Example 1, except that a release agent comprising the release agent composition B shown below was used as a release agent.

(Release agent composition B)

A1: 32 parts by weight of a curing-type silicone resin (molecular weight: 200,000) of the above-mentioned general formula (I) in which the ratio of the methyl group and the hexenyl group to the phenyl group was 100:

A2: 66 parts by weight of a curing-type silicone resin (molecular weight: 200,000) of the above-mentioned general formula (II) in which the ratio of methyl group and vinyl group is 100:

B1: 1 part by weight of the unreactive silicone resin (molecular weight: 80,000) represented by the general formula (IV)

C1: 1 part by weight of an addition type platinum catalyst (PL-50T: Shin-Etsu Chemical Co., Ltd.)

MEK / toluene mixed solvent (mixing ratio is 1: 1)

&Lt; Preparation Example 4 &

(Having a thickness of 25 占 퐉 and a tensile modulus of 3500 占 퐉) having been peeled off with a silicone-based releasing agent in the same manner as in Production Example 3 except that the stretching magnification of the polyethylene terephthalate film was changed to 5.1 times in the longitudinal direction and 5.3 times in the transverse direction MPa).

&Lt; Production Example 5 &

(Thickness: 38 mu m, tensile elastic modulus: 3500 MPa), which had been peeled off with a silicone-based releasing agent, was obtained in the same manner as in Production Example 1, except that a releasing agent comprising the releasing agent composition C shown below was used as a releasing agent.

(Release agent composition C)

A1: 16 parts by weight of a curing-type silicone resin (molecular weight: 200,000) of the above-mentioned general formula (I) in which the ratio of methyl group and hexenyl group to phenyl group was 100:

A2: 33 parts by weight of a curing-type silicone resin (molecular weight: 200,000) of the general formula (II) in which the ratio of the methyl group and the vinyl group is 100:

A3: 16 parts by weight of a curable silicone resin (molecular weight: 200,000) of the above-mentioned general formula (III) in which the ratio of the methyl group and the hydrosilyl group is 100:

A4: 33 parts by weight of a curable silicone resin (molecular weight: 200,000) of the above-mentioned general formula (III) in which the ratio of the methyl group and the hydrosilyl group was 100: 0.4

B1: 1 part by weight of the unreactive silicone resin (molecular weight: 80,000) represented by the general formula (IV)

C1: 1 part by weight of an addition type platinum catalyst (PL-50T: Shin-Etsu Chemical Co., Ltd.)

MEK / toluene mixed solvent (mixing ratio is 1: 1)

&Lt; Production Example 6 &

(Thickness: 25 占 퐉, tensile modulus: 3500 占 퐉) having a thickness of 25 占 퐉 and having a thickness of 25 占 퐉 and peeled with a silicone-based releasing agent were prepared in the same manner as in Production Example 5 except that the stretching magnifications of the polyethylene terephthalate film were changed to 5.1 times in the longitudinal direction and 5.3 times in the transverse direction. MPa).

&Lt; Example 1 >

1. Preparation of Polarizer

(A-PET) film (trade name: NovaClear, thickness: 100 占 퐉) was prepared as a base material and a polyvinyl alcohol (PVA) resin (manufactured by Mitsui Chemicals, Manufactured by Shin-Etsu Chemical Co., Ltd., trade name: GOSEENOL (registered trademark) NH-26) was applied at 60 DEG C and dried to form a PVA resin layer having a thickness of 7 mu m. The laminate thus obtained was immersed in a insolubilizing bath at a liquid temperature of 30 DEG C for 30 seconds (insolubilization step). Subsequently, the substrate was immersed in a dyeing bath at a temperature of 30 DEG C for 60 seconds (dyeing step). Subsequently, the substrate was immersed in a crosslinking bath at 30 占 폚 for 30 seconds (crosslinking step). Thereafter, while the laminate was immersed in an aqueous boric acid solution at a liquid temperature of 60 占 폚, uniaxial stretching was performed in the longitudinal direction (longitudinal direction) between rolls different in the main circumferential direction. The immersion time for the boric acid aqueous solution was 120 seconds, and the laminate was stretched just before fracture. Thereafter, the laminate was immersed in a cleansing bath and then dried with warm air at 60 DEG C (cleaning and drying step). Thus, a long-axis-direction polarizer laminate having a polarizer with a thickness of 5 탆 was formed on the substrate.

Subsequently, a (meth) acrylic resin film having a lactone ring structure with a thickness of 40 탆 was prepared as a protective film constituting the protective layer, and the corona treatment was performed on the easy-to-adhere treated surface of the protective film to obtain a polarizer side (Thickness: 40 占 퐉, tensile elastic modulus: 2650 MPa) / polarizer (thickness: 5 占 퐉, tensile elastic modulus: 650 MPa) by peeling the substrate from the polarizer by peeling the substrate with the protective film Thereby obtaining a long-axis polarizer having a layered structure.

2. Adhesion of release film

A four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas introducing tube and a condenser was charged with a monomer mixture containing 99 parts of butyl acrylate and 1 part of 4-hydroxybutyl acrylate. Further, 0.1 part of 2,2'-azobisisobutyronitrile as a polymerization initiator was introduced into 100 parts of the above monomer mixture (solid content) together with ethyl acetate, and nitrogen gas was introduced while slowly stirring to displace the inside of the flask The polymerization reaction was carried out for 7 hours while maintaining the liquid temperature at around 60 캜. Thereafter, a solution of an acrylic polymer (A-1) having a weight average molecular weight of 1,400,000 was prepared by adding ethyl acetate to the reaction solution and adjusting the solid concentration to 30%.

0.095 part of trimethylolpropane xylylene diisocyanate (trade name: Takenate D110N, manufactured by Mitsui Chemical Co., Ltd.) as a crosslinking agent, 0.075 parts of dibenzoyl peroxide (trade name: (Trade name: X-41-1810, manufactured by Shin-Etsu Chemical Co., Ltd.) as a thiol-based silane coupling agent (C1) And 0.2 part of a silane coupling agent containing an acetoacetyl group (trade name: A-100, manufactured by Soken Chemical Co., Ltd.) as an acetoacetyl group-containing silane coupling agent (C2) were blended to prepare an acrylic pressure-sensitive adhesive solution A.

Then, the acrylic pressure-sensitive adhesive solution A was uniformly coated on the surface of the release film A by using a fountain coater and dried in an air circulating thermostat oven at 155 캜 for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 20 탆 on the surface of the release film A. . Then, a release film A was stuck to the polarizer side of the polarizer plate with a pressure-sensitive adhesive layer interposed therebetween to manufacture a polarizer plate having a release film.

Subsequently, the release film is peeled from the polarizing plate to which the release film is laminated (release step), and the release film peeled off on the polarizer side of the polarizer is again bonded (rejoining step) To prepare a polarizing plate.

3. Adhesion of surface protective film

In a four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas introducing tube and a condenser, 94 parts by mass of 2-ethylhexyl acrylate (2EHA), 1 part by mass of N, N-diethylacrylamide (DEAA) , 1 part by mass of glycol acrylate (EDE), 4 parts by mass of 4-hydroxybutyl acrylate (HBA), 0.2 parts by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, and 150 parts by mass of ethyl acetate, (40% by mass) of the acryl-based polymer (A-2) was prepared by introducing nitrogen gas while slowly stirring and maintaining the liquid temperature in the flask at around 60 ° C for 5 hours. The weight average molecular weight of the acrylic polymer (A-2) was 570,000, and the glass transition temperature (Tg) was -68 占 폚.

A solution (40% by mass) of the acrylic polymer (A-2) was diluted to 20% by mass with ethyl acetate, and 500 parts by mass (solid content: 100% by mass) of isocyanurate of hexamethylene diisocyanate 2 parts by mass (solids content: 2 parts by mass) and 2 parts by mass (solid content: 0.02 parts by mass) of dibutyltin dilaurate (1% by mass ethyl acetate solution) as a crosslinking catalyst were added , And the mixture was stirred to prepare an acrylic pressure-sensitive adhesive solution B.

A transparent polyethylene terephthalate (PET) film (polyester film) having a thickness of 75 탆 was prepared as a surface protective film. The acrylic pressure-sensitive adhesive solution B was coated on the PET film and heated at 130 占 폚 for 1 minute to form a pressure-sensitive adhesive layer having a thickness of 15 占 퐉. Subsequently, a siliconized surface of a polyethylene terephthalate film (thickness: 25 占 퐉) as a separator which was subjected to a silicone treatment on one side was adhered to the surface of the pressure-sensitive adhesive layer to prepare a pressure-sensitive adhesive sheet (surface protective film with a separator attached thereto).

The separator was peeled off from the pressure-sensitive adhesive sheet, and the surface protective film (thickness: 75 m, tensile elastic modulus: 3500 MPa) was bonded to a surface of the polarizing plate having the release film opposite to the release film, Sieve 1 was prepared. The optical laminate 1 has a layer structure of a surface protective film / first pressure-sensitive adhesive layer / polarizing plate / second pressure-sensitive adhesive layer / release film.

The obtained optical laminate 1 was provided for evaluation of peel strength and peeling test. Further, the elasticity index X represented by the following formula (1) was calculated. The results are shown in Tables 1 and 2.

X = A - B - C (One)

A: tensile modulus (MPa) of surface protective film x thickness (mu m) of surface protective film

B: tensile modulus (MPa) of polarizer x thickness (占 퐉) of polarizer

C: tensile modulus of elasticity of the release film (MPa) x thickness of release film (占 퐉)

In the case where the polarizing plate has the first protective layer and the second protective layer, the value of B in the above formula (1) is calculated based on the following formula (2).

B = B1 + B2 + B3 (2)

B1: tensile modulus of the polarizer (MPa) x thickness of the polarizer (占 퐉)

B2: tensile modulus of elasticity of the first protective layer (MPa) x thickness of the first protective layer (mu m)

B3: tensile modulus of elasticity of the second protective layer (MPa) x thickness of the second protective layer (mu m)

&Lt; Example 2 >

An elongated optical laminate 2 was produced in the same manner as in Example 1 except that the release film B was used as the release film. The optical laminate 2 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 3 >

An elongated optical laminate 3 was produced in the same manner as in Example 1 except that the release film C was used as the release film. The optical laminate 3 was provided in the same evaluation as in Example 1. [ The results are shown in Tables 1 and 2.

<Example 4>

An elongated optical laminate 4 was produced in the same manner as in Example 1 except that the release film D was used as the release film. Optical laminate 4 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 5 >

The elongated optical laminate 5 was produced in the same manner as in Example 1 except that the peeling film E was used as the peeling film and the peeling process and the repacking process were not performed when the polarizing plate with the elongated film peeling film was produced Respectively. Optical laminate 5 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 6 >

The elongated optical laminate 6 was produced in the same manner as in Example 1 except that the peeling film F was used as the peeling film and the peeling process and the repacking process were not performed when the polarizing plate with the elongated film peeling film was produced Respectively. The optical laminate 6 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 7 >

An elongated optical laminate 7 was produced in the same manner as in Example 1 except that the release film E was used as the release film. The optical laminate 7 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 8 >

An elongated optical laminate 8 was produced in the same manner as in Example 1 except that the release film F was used as the release film. The optical laminate 8 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 9 >

An elongated optical laminate 9 was produced in the same manner as in Example 1, except that the peeling process and the repacking process were not carried out in the production of the polarizing plate with the elongated film peeling film. Optical laminate 9 was provided in the same evaluation as Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 10 >

An elongated optical laminate 10 was produced in the same manner as in Example 2 except that the peeling process and the repacking process were not carried out in the production of the polarizing plate with the elongated film peeling film. Optical laminate 10 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 11 >

An elongated optical laminate 11 was produced in the same manner as in Example 3, except that the peeling process and the repacking process were not carried out in the production of the polarizing plate having the elongated film peeling film. The optical laminate 11 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 12 >

An elongated optical laminate 12 was produced in the same manner as in Example 4 except that the peeling process and the repacking process were not carried out in the production of the polarizing plate with the elongated film peeling film. The optical laminate 12 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 13 >

(Meth) acrylic resin film having a lactone ring structure with a thickness of 20 탆 was used as the protective film constituting the protective layer (first protective layer), the corona treatment was performed on the easy-adhesion treated surface of the protective film, The protective film, which had been corona-treated on the side of the polarizer side of the body, was laminated, and the substrate was peeled off from the polarizer. Then, a corona treatment was performed on the easy-adhesion treated surface of the protective film using a (meth) acrylic resin film having a lactone ring structure with a thickness of 20 mu m as a protective film constituting the protective layer (second protective layer) (Thickness: 20 占 퐉, tensile elastic modulus: 2650 MPa) / polarizer (thickness: 5 占 퐉, tensile elastic modulus: 650 MPa) / the second protective film To obtain a polarizing plate having a layer structure of a protective layer (thickness: 20 m, tensile elastic modulus: 2650 MPa).

An elongated optical laminate 13 was produced in the same manner as in Example 1 except that the polarizing plate was used. The optical laminate 13 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 14 >

(Meth) acrylic resin film having a lactone ring structure with a thickness of 25 mu m was used as the protective film constituting the protective layer (first protective layer), and a protective film constituting the protective layer (second protective layer) Mu] m of a (meth) acrylic resin film having a lactone ring structure was used in place of the (meth) acrylic resin film having a lactone ring structure. The optical laminate 14 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 15 >

(Meth) acrylic resin film having a lactone ring structure with a thickness of 20 탆 was used as the protective film constituting the protective layer (first protective layer), the corona treatment was performed on the easy-adhesion treated surface of the protective film, The protective film, which had been corona-treated on the side of the polarizer side of the body, was laminated, and the substrate was peeled off from the polarizer. Then, a corona treatment was performed on the easy-adhesion treated surface of the protective film using a (meth) acrylic resin film having a lactone ring structure with a thickness of 20 mu m as a protective film constituting the protective layer (second protective layer) (Thickness: 20 占 퐉, tensile elastic modulus: 2650 MPa) / polarizer (thickness: 5 占 퐉, tensile elastic modulus: 650 MPa) / the second protective film To obtain a polarizing plate having a layer structure of a protective layer (thickness: 20 m, tensile elastic modulus: 2650 MPa).

An elongated optical laminate 15 was produced in the same manner as in Example 9 except that the above polarizing plate was used. The optical laminate 15 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Example 16 >

(Meth) acrylic resin film having a lactone ring structure with a thickness of 25 mu m was used as the protective film constituting the protective layer (first protective layer), and a protective film constituting the protective layer (second protective layer) (Meth) acrylic resin film having a lactone ring structure was used in place of the (meth) acrylic resin film having a lactone ring structure. The optical laminate 16 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 1 &

An elongated optical laminate 17 was produced in the same manner as in Example 5 except that a polyethylene terephthalate (PET) film (thickness: 38 m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 17 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 2 &

An elongated optical laminate 18 was produced in the same manner as in Example 5 except that a polyethylene terephthalate (PET) film (thickness: 50 m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 18 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 3 &

An elongated optical laminate 19 was produced in the same manner as in Example 9 except that a polyethylene terephthalate (PET) film (thickness: 38 mu m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 19 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 4 &

An elongated optical laminate 20 was produced in the same manner as in Example 9 except that a polyethylene terephthalate (PET) film (thickness: 50 m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 20 was subjected to the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 5 &

An elongated optical laminate 21 was produced in the same manner as in Example 11 except that a polyethylene terephthalate (PET) film (thickness: 38 mu m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 21 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

&Lt; Comparative Example 6 >

An elongated optical laminate 22 was produced in the same manner as in Example 11 except that a polyethylene terephthalate (PET) film (thickness: 50 m, tensile elastic modulus: 3500 MPa) was used as the surface protective film. The optical laminate 22 was provided in the same evaluation as in Example 1. The results are shown in Tables 1 and 2.

As is clear from Tables 1 and 2, in the optical laminate of Examples 1 to 16, in which the elasticity index is a positive value, there was no adsorbed trace on the polarizing plate. The optical laminate of the example in which the peeling force Y of the peel film is smaller than the instrument peel force X of the surface protective film has the following characteristics: the peelability of the peel film is high, and the optical laminate of the embodiment having X- , The peelability of the release film is particularly high.

The optical laminate of the present invention is preferably used for an image display device such as a liquid crystal display device, an organic EL display device and the like.

10 Surface Protective Film
20 first pressure-sensitive adhesive layer
30 polarizer
31 polarizer
32 First protective layer
33 Second protective layer
40 second pressure-sensitive adhesive layer
50 release film
100 optical stack
101 optical laminate

Claims (6)

A surface protective film, a first pressure-sensitive adhesive layer, a polarizing plate, a second pressure-sensitive adhesive layer, and a release film in this order,
When the product of the tensile modulus of elasticity of the surface protective film and the thickness is A and the product of the tensile modulus and thickness of the polarizing plate is B and the product of the tensile elastic modulus and the thickness of the release film is C,
A> B + C
Satisfies the following conditional expression. The method according to claim 1,
When the instrument peel force of the surface protective film is X (N / 50 mm) and the instrument peel force of the release film is Y (N / 50 mm)
Y <X
Satisfies the following conditional expression. 3. The method of claim 2,
X - Y > 0.1
. 4. The method according to any one of claims 1 to 3,
The total thickness of the surface protective film and the first pressure sensitive adhesive layer is 75 占 퐉 or more,
And the thickness of the peeling film is 38 占 퐉 or less. 4. The method according to any one of claims 1 to 3,
Wherein the polarizing plate has a polarizer and a protective layer laminated on the surface protective film side of the polarizer,
Wherein the thickness of the polarizer is 12 占 퐉 or less. An image display device comprising the polarizing plate of the optical laminate according to any one of claims 1 to 3 and an optical member in which the polarizing plate is bonded via the second pressure-sensitive adhesive layer.

Images