KR20210027818A - Polarizing plate laminate and image display apparatus comprising same - Google Patents

Abstract

The present invention relates to a polarizing plate laminate with suppressed blocking phenomenon, comprising: a polarizer; a hard coating layer provided on one side or both sides of the polarizer; and a protective film for a process provided on the hard coating layer, wherein the hard coating layer includes a polysiloxane compound, and the peeling force between the hard coating layer and the protective film for a process is 50 gf/5 cm or less at peeling angle of 180 degrees and a peeling rate of 30 m/min, and to an image display device comprising the same.

Description

A polarizing plate laminate and an image display device including the same TECHNICAL FIELD

The present specification relates to a polarizing plate laminate and an image display device including the same.

The image display device may include a display panel and polarizing plates provided on both surfaces of the display panel. The polarizing plate is adhered to the display panel through an adhesive layer, and a protective substrate is provided on the adhesive layer side and the opposite surface of the polarizing plate.

Since the protective substrate provided on the opposite side of the side where the adhesive layer of the polarizing plate is provided must function to protect the polarizing plate from harsh external conditions, high rigidity and low moisture permeability properties are required.

In addition, it is possible to protect the polarizer by forming a hard coating layer on the polarizer instead of the conventional protective substrate. In order to protect the hard coating layer, a process protective film is laminated on the hard coating layer.

At this time, since a blocking phenomenon, which is a phenomenon in which the photocurable composition applied to form the hard coating layer, adheres to the protective film for processing occurs, long-term storage is difficult.

Korean Patent Application Publication 2016-0142546

The present invention relates to a polarizing plate laminate and an image display device including the same.

The present invention includes a polarizer, a hard coating layer provided on one or both sides of the polarizer, and a process protective film provided on the hard coating layer, wherein the hard coating layer includes a polysiloxane compound, and the hard coating layer and the protection for the process It provides a polarizing plate laminate that the peeling force between the films is 50 gf/5cm or less at a peeling angle of 180 degrees and a peeling speed of 30 m/min.

In addition, the present invention provides an image display device including an image display panel and the above-described polarizing plate provided on one or both surfaces of the image display panel.

Since the polarizing plate laminate of the present invention has a small peeling force between the hard coating layer and the process protective film, the blocking phenomenon in which the hard coating layer and the process protective film adhere to each other when the process protective film is peeled off is suppressed.

In addition, the image display device of the present invention can provide a thinned image display device by including a hard coating layer having excellent durability without having a separate protective film.

In addition, as the image display device of the present invention includes a hard coating layer having improved rigidity and low moisture permeability, the image display device can be protected from external factors, thereby improving durability at high temperatures or high humidity.

1 and 2 show a polarizing plate laminate structure of the present invention.

Hereinafter, the present specification will be described in more detail.

In the present specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

In the present specification, when a member is said to be positioned "on" another member, this includes not only the case where the member is in contact with the other member, but also the case where another member exists between the two members.

In the present specification, “polarizing plate” refers to a laminate including “polarizer”, and the polarizing plate may include other configurations in addition to the polarizer. However, when the polarizing plate does not include a configuration other than the polarizer, the polarizing plate and the polarizer may be interpreted in the same manner.

In the present specification, “upper surface” and “lower surface” are for specifying their positions, and “upper surface” and “lower surface” of an arbitrary member may include an arbitrary member therebetween. In addition, "topmost surface" is to describe a member located at the outermost part of the members provided on the "top surface", and "B provided on the top surface of A" means that the opposite side of the surface opposite to A of B It means that the member is not included.

The conventional hard coating layer is formed by directly applying and curing a composition for forming a hard coating layer on a polarizer. At this time, in order to protect the composition for forming the hard coating layer applied to the polarizer, the composition is protected using a process protective film. The hard coating layer is formed by curing the composition for forming the hard coating layer by irradiating UV on the protective film for the process. However, when the peeling force between the hard coating layer and the process protective film is large, when the process protective film is peeled from the hard coating layer, the protective film and the hard coating layer adhere to each other.

Therefore, it is important to lower the peeling force between the hard coating layer and the process protective film.

The present invention includes a polarizer, a hard coating layer provided on one or both sides of the polarizer, and a protective film for a process provided on the hard coating layer, the hard coating layer comprises a polysiloxane compound, the hard coating layer and the protective film for the process It provides a polarizing plate laminate in which the peeling force between is 50 gf/5cm or less at a peeling angle of 180 degrees and a peeling speed of 30 m/min. The protective film for the process of the polarizing plate laminate is introduced to protect the hard coating layer, and has a configuration that can be peeled off after the process for curing the hard coating layer. That is, the hard coating layer of the polarizing plate laminate may be in a cured state or an uncured state of the composition for forming a hard coating layer. This, in the present specification, is expressed as “the hard coating layer includes a cured product of the composition for forming a hard coating layer”.

The hard coating layer includes a polysiloxane compound. That is, the hard coating layer may include a photocurable composition containing a polysiloxane compound. The polysiloxane compound has an effect of lowering the surface energy of the hard coating layer and suppressing a blocking phenomenon in which the hard coating layer and the process film adhere to each other when the process film is laminated on the hard coating layer. In addition, since the polysiloxane compound has a large binding energy, it has excellent heat resistance.

The hard coating layer may include a polysiloxane compound having a cyclic polysiloxane structure. That is, the polysiloxane compound may have a cyclic polysiloxane structure. In the present specification, "cyclic polysiloxane structure" refers to a structure having two or more siloxane units (Si-O-Si) in the constituent elements of the ring. When the polysiloxane compound includes a cyclic polysiloxane structure, it has an advantage of excellent heat resistance compared to the case where the polysiloxane compound includes a linear polysiloxane structure. Specifically, by including a cyclic structure in the molecular structure, high-temperature durability can be improved by increasing the crosslinking density of the cured product. In addition, due to the water repellency, which is a characteristic of siloxane, the protective function of the hard coating layer can be improved in a high humidity environment. That is, the polysiloxane compound includes a cyclic polysiloxane structure, thereby improving durability in a high temperature and high humidity environment.

The polysiloxane compound may include a cyclic polysiloxane structure in a main chain or a side chain, and preferably may be included in the main chain. In this case, it has an advantage of excellent heat resistance.

The polysiloxane compound may contain two or more cationic polymerizable functional groups. In this case, the cationic polymerizable functional groups may be the same or different from each other.

The cationic polymerizable functional group may be an epoxy group, a vinyl ether group, an oxetane group or an alkoxysilyl group, and an epoxy group is preferable. The epoxy group may be an alicyclic epoxy group.

The polysiloxane compound is commercially available KR-470” [4-functional epoxy cyclic siloxane compound: manufactured by Shin-Etsu Chemical Co., Ltd.] and “X-40-2678” [2-functional epoxy cyclic siloxane compound: manufactured by Shin-Etsu Chemical Co., Ltd.] And the like.

The content of the polysiloxane compound may be 6 parts by weight or more and 50 parts by weight based on 100 parts by weight of the hard coating layer. The lower limit may be 8 parts by weight or more, more preferably 10 parts by weight or more. In addition, the upper limit may be 50 parts by weight or less, preferably 30 parts by weight or less, more preferably 20 parts by weight or less, and most preferably 10 parts by weight or more and 20 parts by weight or less. 100 parts by weight of the hard coating layer may be based on 100 parts by weight of the solid content of the photocurable composition for forming the hard coating layer. When the above range is satisfied, the polysiloxane compound effectively lowers the surface energy of the hard coating layer, thereby suppressing the blocking phenomenon.

The polarizing plate laminate may be attached to an image display panel to constitute an image display device.

With reference to FIG. 1, the structure of the polarizing plate laminated body of this invention is demonstrated. 1 is a schematic cross-sectional view of a polarizing plate laminate of the present invention.

Referring to Figure 1, the polarizing plate laminate 100 of the present invention is a polarizer 10; A hard coating layer 20 provided on one side of the polarizer; And a process protective film 30 provided on the hard coating layer 20.

Referring to FIG. 2, the polarizing plate stack 100 may be adhered to the display panel through the adhesive layer 40. In this case, the protective film 30 for the process of the polarizing plate laminate 100 may be peeled off.

The adhesive layer may be a conventional adhesive.

The pressure-sensitive adhesive layer may use a conventional pressure-sensitive adhesive, and may be formed from a composition for an adhesive layer including a curing agent or a coupling agent in an adhesive resin such as a (meth)acrylic resin, an epoxy resin, or a silicone resin.

The display panel 300 may be a liquid crystal panel in a twisted nematic (TN) mode, an in-plane switching (IPS) mode, a fringe field switch (FFS) mode, or a vertical alignment (VA) mode. The liquid crystal panel may include an upper substrate, a lower substrate, and a liquid crystal layer enclosed between the upper and lower substrates.

The upper substrate and the lower substrate may be the same or different, and may be a glass substrate or a plastic substrate, respectively. The plastic substrate is PET (polyethylene terephthalate), PC (polycarbonate), PI (polyimide), PEN (polyethylenenaphthalate), PES (polyethersulfone), PAR (polyarylate), and COC (cycloolefin copolymer) that can be used in flexible displays. It may be a plastic substrate of, but the present invention is not limited thereto.

The liquid crystal layer may include a liquid crystal having a positive or negative dielectric anisotropy. The dielectric anisotropy of the liquid crystal layer may be appropriately selected according to a mode of a desired liquid crystal panel. In one example, a phase retardation value of the liquid crystal layer may be 270 nm to 330 nm, and a retardation value in a thickness direction may be 0 nm to -40 nm.

Upper and lower substrates of the liquid crystal panel may further include alignment layers toward the liquid crystal layer. The alignment direction of the liquid crystal may be determined by the alignment layer. The alignment layer may be a horizontal alignment layer. As the alignment layer, a rubbing alignment layer or a photo alignment layer may be used.

The peeling force between the hard coating layer and the process protective film may be 50 gf/5cm or less, preferably 40 gf/5cm or less, and more preferably 30 gf/5cm or less at a peeling angle of 180 degrees. The lower limit of the peeling force is not particularly limited, but may be preferably 5gf/5cm or more. When the above numerical range is satisfied, it is possible to effectively prevent the occurrence of a blocking phenomenon between the hard coating layer and the process protection film when the process protection film is peeled off.

The peel force between the hard coating layer and the process protective film may be measured at a speed of 30 m/min at 180 degrees according to ASTM D3330. For example, it can be measured using a film fast peeling machine (CBT-4720, Chungbuk Tech).

The peeling force between the hard coating layer and the process protective film may be measured after leaving the polarizing plate laminate at room temperature (25° C.) and a relative humidity of 30% to 60% for 100 hours. A preferred value of the relative humidity is 50%.

Peeling force between the hard coating layer and the polarizer may be 4B or more, and 4B or more and 5B or less, preferably 5B, as measured by an ASTM standard cross-cut tape test according to measurement standard D3359-87. Can be The peeling force between the hard coating layer and the polarizer may be a value measured after leaving the polarizing plate laminate at room temperature (25° C.) and 30% to 45% relative humidity for 1 hour to 100 hours, and preferably, a relative humidity of 43 It may be a value measured in %. When the peeling force between the hard coating layer and the polarizer is equal to the above value, the adhesion of the hard coating layer to the polarizer is excellent, so that when the process protective film is peeled from the hard coating layer, the phenomenon that the hard coating layer is lifted from the polarizer can be suppressed. have. In addition, when it is smaller than 4B, the polarizer may be discolored or polarization characteristics may be deteriorated.

Peeling force between the hard coating layer and the polarizer may be measured by a cross-cut tape test.

In the cross-cut test method, a cross cutter is used on the hard coating layer from which the protective film for processing has been peeled off, against a cutting guide or a suitable ruler, and drawn in a grid pattern horizontally and vertically in the shape of a banuk pan eye at 1 mm intervals on the sample. . After that, after washing the surface of the hard coating layer with a brush or a dust-free cloth, attach an Ichibang tape (Cellotape manufactured by Nichiban Co., Ltd.). Observe. Thereafter, the degree of adhesion is classified from 0B to 5B according to the crosscut classification criteria (ASTM).

Conventionally, by laminating a protective film on the upper surface of a polarizer included in a display panel, a polarizing plate has been protected from harsh external environments. However, since the protective film is thick, there is a problem that it is difficult to reduce the thickness of the image display device, and the adhesive used when laminating the protective film has a problem in that the adhesive strength decreases in a high temperature and high humidity environment, and the protective film is peeled off.

In the present invention, by providing a hard coating layer on one side of the polarizer instead of the conventional protective film, the hard coating layer is prevented from being peeled off even without a separate adhesive layer. In addition, by controlling the maximum value of the loss tangent coefficient tanδ of the hard coating layer to be 0.6 or less, high temperature durability could be improved.

Hard coating layer

The hard coating layer 20 functions to effectively protect the polarizer 10.

The hard coating layer 20 has excellent properties in physical and/or chemical durability, and has excellent optical properties.

The hard coating layer 20 may be directly provided on one or both surfaces of the polarizer. The “directly provided” means that no other layer is provided between the hard coating layer and the polarizer.

The maximum value of the loss tangent coefficient tanδ of the hard coating layer 20 may be 0.6 or less, preferably 0.5 or less, and more preferably 0.4 or less. When satisfying the above range, the heat resistance and durability of the hard coating layer may be excellently maintained.

The tan δ (tan Delta) means the ratio of the storage modulus and the loss modulus. Specifically, the tan δ (tan Delta) may be expressed by the following equation.

tanδ(tan Delta) = storage modulus / loss modulus

In order to measure the tanδ (tan Delta), a cured film was prepared by first coating a release film with the same composition as the hard coating layer, and ^{irradiating a light amount of 1,000 mJ/cm 2 at a temperature of 23°C and a relative humidity of 55%.} do. In this case, the thickness of the cured film is 30 μm to 50 μm, and may be, for example, 30 μm. After removing the release film, a specimen prepared in the size of width x length x thickness (5.3mm x 10mm x 30㎛) was used with a temperature sweep test (Amplitude 10㎛, Preload force 0.01N, Force) using DMA Q800 (TA instrument). Track 125%, Frequency 1Hz) from -10℃ to 160℃ at 5℃/min and measure the storage modulus. Record the measured storage modulus divided by the measured loss modulus, and calculate tanδ (tan Delta) at the maximum value.

The maximum value of the loss tangent coefficient tanδ of the hard coating layer 20 appears in the temperature range of 90°C to 120°C, preferably in the temperature range of 95°C to 120°C, and more preferably in the temperature range of 100°C to 120°C. I can. The temperature at which the maximum value of the loss tangent coefficient tanδ appears may be defined as Tmax.

Since the hard coating layer 20 functions to protect other components, the higher the thickness, the better the protection function, but the optical properties may be deteriorated. Therefore, it is important to control the thickness within a certain range to ensure a protective function and prevent the optical properties from deteriorating. Specifically, the thickness of the hard coating layer may be 5 µm to 15 µm, preferably 5 µm to 10 µm, more preferably 6 µm to 9 µm. When the thickness exceeds 15 μm, there is a problem that the optical properties of the hard coating layer are deteriorated, and when the thickness of the hard coating layer is less than 5 μm, the protective function is deteriorated and durability at high temperature or high humidity is lowered.

In addition, the thickness of the hard coating layer 20 can be measured by measuring the cross section of the image display device using the FESEM SU-8020 SYSTEM equipment (measurement conditions: acceleration voltage 2 kV, emission current: 10uA, working distance: 8mm, detector : SE).

The hard coating layer 20 has low moisture permeability. Specifically, the moisture permeability (WVTR) of the hard coating layer is 200 g/m ² *day or less, preferably 150 g/m ² *day or less, more preferably 120 g/m ² *day or less at a temperature of 38°C. I can.

The moisture permeability refers to the amount of moisture per unit time and per unit area in a constant external environment, and can be measured in an environment where the difference in humidity between the inside and the outside of the film is 90%, and the moisture permeability is Labthink's WVTR equipment (equipment Name: WVTR TSY-T3) can be measured. The equipment has a structure with a scale in a sealed chamber, and the environment in the chamber is maintained at 38°C and 10% humidity. In addition, after water is poured into the moisture-permeable cup, a specimen having the same composition as the hard coating layer is covered and fixed thereon. Since the moisture inside the moisture permeable cup is 100% full of water, the difference between the humidity inside and outside the moisture permeable cup is 90%. After 24 hours, the weight of the moisture permeable cup is measured, and the amount of evaporated water can be calculated through the difference from the initial weight.

The hard coating layer 20 has a characteristic that the absolute value of the photoelastic coefficient is low. Specifically, the hard coating layer 20 has an absolute value of the photoelastic coefficient of 12 x 10 ^-12 m ² /N or less, preferably 11 x 10 ^-12 m ² /N or less, more preferably 10.8 x 10 ^-12 It may be less than or equal to ^{m 2 /N.} When it exceeds the above range, there is a problem in that optical distortion occurs due to stress under high temperature and high humidity conditions, and thus light leakage occurs.

The photoelastic coefficient is defined as the degree of expression of birefringence (Δn) with respect to the stress (ΔF) applied to an isotropic solid (relational expression: c=Δn/ΔF). As a measurement method, after cutting a specimen having the same composition as the hard coating layer into a size of 40 to 50 μm thick and 15 mm wide x 100 mm long, use a polarization spectrophotometer at a temperature of 25° C. and a relative humidity of 50%. Can be measured. After fixing both ends of the specimen with a support, the birefringence according to the change in the load (Stress) is measured, and the photoelastic coefficient is measured from the slope.

The hard coating layer 20 has excellent strength against external impact. Specifically, the pencil hardness of the hard coating layer may be HB or more and 9H or less, preferably 1H or more and 9H or less. The pencil hardness of the hard coating layer can be measured by the test method of JIS K 5600 5-4. After preparing a specimen having the same composition as the hard coating layer, a pencil lead having a hardness to be measured is fixed on a pencil hardness tester. Thereafter, the tip of the pencil lead of the hardness to be measured is flattened, and the pencil lead is placed on the specimen so that the end surface of the pencil lead and the surface of the specimen form a 45 degree angle. After installing a weight so that a load of 500g is applied to the tip of the pencil lead, inspect the surface visually while moving the pencil at a speed of 5mm/sec.

The storage modulus of the hard coating layer 20 at 80° C. is preferably 800 Mpa to 10,000 Mpa, more preferably 1,000 Mpa to 5,000 Mpa, and most preferably 1,500 Mpa to 3,500 Mpa. When the storage modulus of the hard coating layer satisfies the numerical range, there is an effect of effectively suppressing the occurrence of cracks in the polarizer due to contraction or expansion of the polarizer in a high temperature or high humidity environment. In addition, it is possible to improve the adhesion to the polarizing plate. Accordingly, by suppressing contraction and expansion of the polarizing plate at a high temperature, it is possible to prevent the occurrence of light leakage as well as excellent adhesion.

The hard coating layer 20 may have a refractive index of 1.4 or more and 1.5 or less at a wavelength of the D-line. In this case, the light source of the D-line wavelength may be an LED lamp.

The hard coating layer 20 may be formed by coating and curing the photocurable composition on the upper surface of the polarizer 10. That is, the hard coating layer 20 may include a cured product of the photocurable composition. The photocurable composition refers to a composition in which curing proceeds by irradiation of light.

Meanwhile, the coating method is not particularly limited, and may be formed by a method well known in the art. For example, a hard coating layer is formed by applying the photocurable composition to at least one surface of a polarizer by a coating method well known in the art, such as spin coating, bar coating, roll coating, gravure coating, and blade coating. Next, it may be formed by using an ultraviolet irradiation device to irradiate ultraviolet rays, which is irradiation light.

The wavelength of the ultraviolet rays is preferably 100 nm to 400 nm, more preferably 320 nm to 400 nm. Further, the irradiation light amount is more preferably 100mJ / cm ² to 1000mJ / cm ² are preferred, and 500mJ / cm ² to 1000mJ / cm ^2.

The irradiation time of the irradiation light is preferably 1 second to 10 minutes, more preferably 2 seconds to 30 seconds. When the irradiation time range is satisfied, there is an advantage of preventing excessive heat transfer from the light source, thereby minimizing the occurrence of running wrinkles in the polarizer.

Process protective film

The protective film for the process is a configuration introduced to protect the photocurable composition applied to the polarizer. The remaining configuration obtained by peeling the protective film for the process from the polarizing plate laminate may be used as a polarizing plate.

The type of the protective film for the process is not particularly limited, and polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, acrylic polymers such as polymethyl methacrylate, polystyrene and acrylonitrile-styrene copolymer (AS resin) Styrene polymers, polycarbonate polymers, and the like can be used.

In addition, polyethylene, polypropylene, polyolefins having a cyclo-based or norbornene structure, polyolefin-based polymers such as ethylene-propylene copolymers, vinyl chloride-based polymers, amide-based polymers such as nylon and aromatic polyamides, imide-based polymers, and Pone polymer, polyether sulfone polymer, polyether-etherketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, allylate polymer, polyoxymethylene polymer , Epoxy polymer, blend polymer of the polymer, acrylic, urethane, acrylic urethane and epoxy-based, it is preferable to use a thermosetting or ultraviolet-curable resin such as silicone, alone or in combination.

The thickness of the protective film for the process may be 10 μm to 100 μm, preferably 20 μm to 80 μm, more preferably 30 μm to 70 μm.

The polarizer may be a polarizer well known in the art, for example, a film made of polyvinyl alcohol (PVA) containing iodine or a dichroic dye. The polarizer may be manufactured by dyeing iodine or a dichroic dye to a polyvinyl alcohol-based film, but a method of manufacturing the polarizer is not particularly limited. In the present specification, the polarizer refers to a state that does not include a hard coating layer (or protective film), and the polarizing plate refers to a state including a polarizer and a hard coating layer (or protective film).

The polarizing plate is a process of uniaxially stretching a polyvinyl alcohol-based resin film, a process of dyeing a polyvinyl alcohol-based resin film with a dichroic dye and adsorbing the dichroic dye, a polyvinyl alcohol-based resin film adsorbed with a dichroic dye It is manufactured through a process of treating with an aqueous boric acid solution, a process of washing with water after treatment with an aqueous boric acid solution, and bonding a hard coating layer to a uniaxially stretched polyvinyl alcohol-based resin film in which a dichroic dye is adsorbed and oriented. .

The uniaxial stretching may be performed before dyeing with a dichroic dye, simultaneously with dyeing with a dichroic dye, or after dyeing with a dichroic dye. When uniaxial stretching is performed after dyeing with a dichroic dye, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. In addition, it is also possible to uniaxially stretch in a plurality of these steps. In order to perform uniaxial stretching, it may be uniaxially stretched between rolls having different circumferential speeds or uniaxially stretched using a heat roll. Further, it may be dry stretching performed in the air, or wet stretching performed in a state swollen with a solvent. The draw ratio is not particularly limited, but is usually 4 to 8 times.

Meanwhile, the polarizer preferably has a thickness of 5 μm to 40 μm, and more preferably 5 μm to 25 μm. If the thickness of the polarizer is thinner than the above numerical range, optical properties may deteriorate, and if the thickness of the polarizer is thicker than the above numerical range, the amount of shrinkage of the polarizer at a low temperature (for example, -30°C) increases, thereby reducing the overall durability of the polarizing plate in relation to heat. .

In addition, when the polarizer is a polyvinyl alcohol-based film, the polyvinyl alcohol-based film may be used without particular limitation as long as it includes a polyvinyl alcohol resin or a derivative thereof. In this case, the derivatives of the polyvinyl alcohol resin include polyvinyl formal resin and polyvinyl acetal resin, but are not limited thereto. In addition, commercially available polyvinyl alcohol-based films such as P30, PE30, PE60 from Guraray, M2000, M3000, M6000, etc. from Japan Synthetic Company may be used, but the present invention is not limited thereto.

The polyvinyl alcohol-based film preferably has a degree of polymerization of 1,000 to 10,000, and more preferably 1,500 to 5,000. When the degree of polymerization satisfies the above numerical range, the movement of molecules is free and can be flexibly mixed with iodine or a dichroic dye.

The protective film 50 may be a polymer film. As the polymer film, for example, a polyolefin film such as a polyethylene film or a polypropylene film, a cyclic olefin polymer (COP) film such as a polynorbornene film, a polyvinyl chloride film, a polyacrylonitrile film, a poly A cellulose ester-based polymer film such as a sulfone film, a polyacrylate film, a polyvinyl alcohol film, or a triacetyl cellulose (TAC) film, or a copolymer film of two or more monomers among monomers forming the polymer may be exemplified.

The polymer film may be a resin containing a substituted or unsubstituted styrene group in the main chain and/or a blend containing the resin. More specifically, as the resin containing the substituted or unsubstituted styrene group, styrene-acrylonitrile copolymer (SAN), methyl methacrylate-styrene (MS), styrene-maleic anhydride (SMA), styrene-maleic anhydride- A resin containing a methyl methacrylate copolymer can be used. More specifically, the polymer film may include an acrylic resin including a resin containing a substituted or unsubstituted styrene group. As the acrylic resin, an acrylic resin composed of methacrylic acid ester and acrylic acid ester may be used. The acrylic resin may include an acrylic copolymer resin including a ring structure such as N-substituted maleimide, lactone ring, glutalimide, and maleic anhydride. The glass transition temperature of the resin included in the polymer film may be 100°C or higher, preferably 110°C or higher. The thickness of the polymer film may be 80 μm or less. The polymer film may be produced by extrusion or casting, and biaxial stretching (simultaneous or sequential).

The hard coating layer may include a cured product of a cationic photocurable composition. That is, the photocurable composition may be a cationic photocurable composition.

The hard coating layer may include a cured product of a photocurable composition including an epoxy compound and an oxetane compound. That is, the photocurable composition may include an epoxy compound and an oxetane compound.

The epoxy compound is for lowering the coefficient of thermal expansion after curing of the composition, and includes an alicyclic epoxy compound, an aliphatic epoxy compound, an aromatic epoxy compound, a hydrogenated epoxy compound, or an epoxy group-containing (meth)acrylic compound. These may be used alone or in combination of two or more.

The alicyclic epoxy compound includes one or more alicyclic epoxy rings, and refers to a compound in which the epoxy group is formed between two adjacent carbon atoms constituting the aliphatic ring. For example, dicyclopentadiene dioxide, limonene dioxide, 4-vinylcyclohexene dioxide, 2,4-epoxycyclohexylmethyl, 3,4-epoxycyclohexanecarboxylate, dicyclopentadiene dioxide, bis(3, 4-epoxycyclohexylmethyl) adipate, and the like, but are not limited thereto. In addition, 3,4-epoxycyclohexylmethyl-3,4'-epoxycyclohexanecarboxylate is preferable to lower the coefficient of thermal expansion after curing of the composition and to impart the hardness of the adhesive layer formed from the composition. Do.

Examples of the aliphatic epoxy compound include novolac epoxy, bisphenol A epoxy, bisphenol F epoxy, 1,4-cyclohexanedimethanol diglycidyl ether, 1,4-butanedioldiglycidyl ether, 1,6-hexane Diol diglycidyl ether, neopentyl diglycidyl ether, resorcinol diglycidyl ether, diethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, n -Butyl glycidyl ether, 2-ethylhexyl glycidyl ether, etc. are mentioned.

The aromatic epoxy compound means an epoxy compound containing at least one aromatic hydrocarbon ring in the molecule, but is not limited thereto, for example, diglycidyl ether of bisphenol A, 4,4'-methylenediphenol digly Bisphenol-type epoxy resins such as cidyl ether, diglycidyl ether of bisphenol F, and diglycidyl ether of bisphenol S; Novolac-type epoxy resins such as phenol novolac epoxy resin, cresol novolac epoxy resin, and hydroxybenzaldehyde phenol novolac epoxy resin; And polyfunctional epoxy resins such as glycidyl ether of tetrahydroxyphenyl methane, glycidyl ether of tetrahydroxybenzophenone, and epoxidized polyvinylphenol.

The hydrogenated epoxy compound refers to an epoxy compound obtained by selectively hydrogenating the aromatic epoxy compound under pressure in the presence of a catalyst, and is not limited thereto, but among others, hydrogenated diglycidyl ether of bisphenol A It is preferable to use.

The epoxy group-containing (meth)acrylic compound refers to a compound including both an epoxy group and a (meth)acryloyloxy group in a molecule, and is not limited thereto, for example, glycidyl acrylate, 2-methylglyci Dyl acrylate, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 3,4-epoxycyclohexyl acrylate, glycidyl methacrylate, 2-methylglycidyl methacrylate, 3 , 4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether, and the like.

The epoxy compound may be an epoxy compound containing at least one alicyclic epoxy group.

The epoxy compound including one or more alicyclic epoxy groups may have two or more epoxy groups in the molecule, and at least one of the epoxy groups may be an alicyclic epoxy group. The epoxy compound including at least one alicyclic epoxy group may improve adhesion strength to other members of the composition. In addition, the glass transition temperature of the composition is increased to ensure sufficient durability of the adhesive layer, so that the occurrence of cracks in the polarizer can be prevented even under heat resistance or thermal shock conditions.

The epoxy compound including at least one alicyclic epoxy group may be one that does not substantially have an aromatic ring. In this case, photocuring efficiency may be improved, and optical properties after curing such as weather resistance and refractive index may be improved.

The epoxy compound including one or more alicyclic epoxy groups may have two or more epoxy groups in the molecule, and all of the epoxy groups may be alicyclic epoxy groups. In this case, the adhesive strength of the adhesive composition to other members can be further improved.

The number of carbon atoms of the alicyclic ring of the epoxy compound containing at least one alicyclic epoxy group may be 4 to 10, preferably 6.

The alicyclic ring of the epoxy compound containing at least one alicyclic epoxy group may be substituted or unsubstituted, and examples of the substituent include an alkyl group having 1 to 20 carbon atoms. In the carbon number range, the curing speed and the adhesive strength after curing may be improved. The alkyl group, unless otherwise specified, may mean a straight, branched or cyclic alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, and , The alkyl group may be optionally substituted by one or more substituents, or may be unsubstituted.

The epoxy compound containing at least one alicyclic epoxy group includes at least one alicyclic epoxy ring, and refers to a compound in which the epoxy group is formed between two adjacent carbon atoms constituting an aliphatic ring, and an alicyclic epoxy compound It may be named as, and may be a compound having at least one epoxy group bonded to an alicyclic ring in the molecule as represented by the following formula a1.

[Formula a1]

In Formula a1, m is an integer of 2 to 5, and the group _{obtained by removing one or more hydrogen atoms in (CH 2} )m in Formula a1 is a compound bonded to another chemical structure without an aromatic ring is an alicyclic epoxy compound. I can. That is, it may mean a compound containing one or more epoxidized aliphatic cyclic groups.

Examples of the epoxy compound including at least one alicyclic epoxy group may be represented by the following formula, but is not limited thereto.

As the epoxy compound including at least one alicyclic epoxy group, an epoxycyclohexylmethyl epoxycyclohexanecarboxylate-based compound represented by the following Formula 1 may be exemplified.

[Formula 1]

In Formula 1, R ₁ and R ₂ each independently represent hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, an epoxycyclohexane carboxylate-based compound of an alkanediol represented by the following formula (2) may be mentioned.

[Formula 2]

In Formula 2, R ₃ and R ₄ each independently represent hydrogen or an alkyl group, and n represents an integer of 2 to 20.

As another example of the epoxy compound containing at least one alicyclic epoxy group, an epoxy cyclohexylmethyl ester-based compound of dicarboxylic acid represented by the following formula (3) may be mentioned.

[Formula 3]

In Formula 3, R ₅ and R ₆ each independently represent hydrogen or an alkyl group, and p represents an integer of 2 to 20.

As another example of the epoxy compound containing at least one alicyclic epoxy group, an epoxycyclohexylmethyl ether compound of polyethylene glycol represented by the following formula (4) may be mentioned.

[Formula 4]

In Formula 4, R ₇ and R ₈ each independently represent hydrogen or an alkyl group, and q represents an integer of 2 to 20.

As another example of the epoxy compound containing at least one alicyclic epoxy group, an epoxycyclohexylmethyl ether compound of an alkanediol represented by the following formula (5) may be mentioned.

[Formula 5]

In Formula 5, R ₉ and R ₁₀ each independently represent hydrogen or an alkyl group, and r represents an integer of 2 to 20.

As another example of the epoxy compound containing at least one alicyclic epoxy group, a diepoxy citris pyro compound represented by the following formula (6) may be mentioned.

[Formula 6]

In Formula 6, R ₁₁ and R ₁₂ each independently represent hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, a diepoxy monospiro-based compound represented by the following formula (7) may be mentioned.

[Formula 7]

In Formula 7, R ₁₃ and R ₁₄ each independently represent hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, a vinylcyclohexene diepoxide compound represented by the following formula (8) may be mentioned.

[Formula 8]

In Formula 8, R ₁₅ represents hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, an epoxycyclopentyl ether compound represented by the following formula (9) may be mentioned.

[Formula 9]

In Formula 9, R ₁₆ and R ₁₇ each independently represent hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, a diepoxy tricyclodecane compound represented by the following formula (10) may be mentioned.

[Formula 10]

In Formula 10, R ₁₈ represents hydrogen or an alkyl group.

As another example of the epoxy compound containing at least one alicyclic epoxy group, more specifically, an epoxycyclohexylmethyl epoxycyclohexane carboxylate compound, an epoxycyclohexane carboxylate compound of an alkanediol, an epoxycyclohexylmethyl ester compound of a dicarboxylic acid Or it is preferable to use an epoxycyclohexylmethyl ether compound of an alkanediol, and 7-oxabicyclo[4,1,0]heptane-3-carboxylic acid and (7-oxa-bicyclo[4,1,0]hepto -3-yl) esterified product with methanol (a compound in which R ₁ and R ₂ are hydrogen in Formula 1); Ester of 4-methyl-7-oxabicyclo[4,1,0]heptane-3-carboxylic acid with (4-methyl-7-oxa-bicyclo[4,1,0]hepto-3-yl)methanol Cargo (in Formula 1, R ₁ is 4-CH ₃ , R ₂ is a compound of 4-CH ₃ ); Esterified product of 7-oxabicyclo[4,1,0]heptane-3-carboxylic acid and 1,2-ethanediol (a compound in which R ₃ and R ₄ are hydrogen and n is 2 in Formula 2); (7-oxabicyclo[4,1,0]hepto-3-yl) an esterified product of methanol and adipic acid (a compound in which R ₅ and R ₆ are hydrogen and p is 2 in Chemical Formula 3); (4-methyl-7-oxabicyclo[4,1,0]hepto-3-yl)methanol and adipic acid esterified product (R ₅ and R ₆ in Formula 3 are 4-CH ₃ and p is 2 phosphorus compound); And an ether product of (7-oxabicyclo[4,1,0]hepto-3-yl)methanol and 1,2-ethanediol (in Formula 5, R ₉ and R ₁₀ are hydrogen and r is 2 ) One or more selected from the group consisting of may be preferably used, but is not limited thereto.

The epoxy compound containing at least one alicyclic epoxy group is for increasing the glass transition temperature (Tg) of the composition and imparting the hardness of the adhesive layer formed from the composition, 3,4-epoxycyclohexylmethyl- 3,4'-epoxycyclohexanecarboxylate is preferred.

The oxetane compound is not particularly limited as long as it has at least one oxetanyl group in the molecule, and various oxetane compounds well known in the art may be used. For example, as the oxetane compound of the present invention, 3-ethyl-3-[(3-ethyloxetan-3-yl)methoxymethyl]oxetane, 1,4-bis[(3-ethyloxy) Cetan-3-yl)methoxymethyl]benzene, 1,4-bis[(3-ethyloxetan-3-yl)methoxy]benzene, 1,3-bis[(3-ethyloxetan-3-yl) ) Methoxy] benzene, 1,2-bis [(3-ethyl oxetan-3-yl) methoxy] benzene, 4,4'-bis [(3-ethyloxetan-3-yl) methoxy] ratio Phenyl, 2,2'-bis[(3-ethyloxetan-3-yl)methoxy]biphenyl, 3,3',5,5'-tetramethyl-4,4'-bis[(3-ethyl Oxetan-3-yl)methoxy]biphenyl, 2,7-bis[(3-ethyloxetan-3-yl)methoxy]naphthalene, bis[4-{(3-ethyloxetan-3-yl) )Methoxy}phenyl]methane, bis [2-{(3-ethyloxetan-3-yl)methoxy}phenyl]methane, 2,2-bis[4-{(3-ethyloxetan-3-yl) )Methoxy}phenyl]propane, a modified product of the etherification of a novolac-type phenol-formaldehyde resin with 3-chloromethyl-3-ethyloxetane, 3(4),8(9)-bis[(3-ethyl Oxetan-3-yl)methoxymethyl]-tricyclo[5.2.1.0 2,6]decane, 2,3-bis[(3-ethyloxetan-3-yl)methoxymethyl]norbornane, 1 ,1,1-tris[(3-ethyloxetan-3-yl)methoxymethyl]propane, 1-butoxy-2,2-bis[(3-ethyloxetan-3-yl)methoxymethyl] Butane, 1,2-bis[{2-(3-ethyloxetan-3-yl)methoxy}ethylthio]ethane, bis[{4-(3-ethyloxetan-3-yl)methylthio}phenyl ]Sulfide, 1,6-bis[(3-ethyloxetan-3-yl)methoxy]-2,2,3,3,4,4,5,5-octafluorohexane, etc. It is not limited.

The photocurable composition may further include a photoinitiator, a photosensitizer, or a photosensitizer.

The photoinitiator may be an iodine-based compound that absorbs a wavelength of 310 nm or less. Specifically, the photoinitiator refers to an iodine-based compound that is activated by absorbing a wavelength of 310 nm or less to produce a cation or Lewis acid by irradiation of active energy. For example, diphenyliodonium hexafluorophosphate (Iod-PF ₆ ), diphenyliodonium triflate (Iod-OSO ₂ CF ₃ ), diphenyliodonium p-toluenesulfonate (Iod-OSO ₂ PhCH ₃ ), diphenyliodonium chloride (Iod-Cl), [4-methylphenyl-(4-(2-methylpropyl)phenyl)]iodonium hexafluorophosphate (Irgacure 250), and the like, [4- Methylphenyl-(4-(2-methylpropyl)phenyl)]iodonium hexafluorophosphate (Irgacure 250) is preferred, but is not limited thereto.

The content of the photoinitiator is preferably 2 to 5 parts by weight, and more preferably 2.5 to 3.5 parts by weight, based on 100 parts by weight of the total photocurable composition. When the photoinitiator is included in an amount within the above numerical range, ultraviolet rays can effectively reach the inside of the hard coating layer, the polymerization rate is excellent, and the molecular weight of the resulting polymer can be prevented from decreasing. Therefore, there is an advantage of excellent cohesion and adhesion to the polarizer of the hard coating layer to be formed.

The photocurable composition includes a photosensitizer. The photosensitizer may be a thioxanthone-based photosensitizer.

The thioxanthone-based photosensitizer may be an alkyl thioxanthone-based, alkoxy thioxanthone-based, or halo thioxanthone-based photosensitizer. The specific structure is shown in Formula B below.

[Formula B]

In Formula B, R ₁ ′ to R ₈ ′ are the same or different, and each independently hydrogen; Halogen group; A substituted or unsubstituted alkyl group; Or it may be a substituted or unsubstituted alkoxy group.

In Formula B, R ₁ ′ to R ₈ ′ are the same or different, and each independently hydrogen; Halogen group; A substituted or unsubstituted C 1 to C 8 alkyl group; Or it may be a substituted or unsubstituted C 1 to C 8 alkoxy group.

More specific examples of the thioxanthone-based photosensitizer include 2-isopropyl thioxanthone, 4-isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4-dichloro thioxanthone, 1 -Chloro-4-propoxythioxanthone, etc. are mentioned.

The content of the photosensitizer may be 0.01 to 0.4 parts by weight based on the total 100 parts by weight of the photocurable composition, preferably 0.1 to 0.3 parts by weight. When the photosensitizer is included in the above numerical range, the photoinitiator of 310 nm or less can be efficiently initiated by receiving ultraviolet rays of 380 nm or more, and the resulting polymer is effectively cured to the inside of the hard coating layer, resulting in excellent polymerization rate, and the resulting polymer The molecular weight of can be prevented from decreasing.

The photocurable composition further includes a photosensitization aid. Specifically, the photosensitization aid may be a naphthalene-based compound.

The photosensitizing aid may be a compound represented by the following formula (C).

[Formula C]

In Formula C,

R ₁₁ ′ and R ₁₂ ′ are the same as or different from each other, and each independently represent an alkyl group having 1 to 6 carbon atoms.

Types of the photosensitizing aid include 1,4-dimethoxy naphthalene, 1-ethoxy-4-methoxy naphthalene, 1,4-diethoxy naphthalene, 1,4-dipropoxy naphthalene, and 1,4-dibutoxy And naphthalene.

The content of the photosensitizing aid is preferably 1 to 3 parts by weight, and more preferably 1 to 2 parts by weight, based on 100 parts by weight of the total photocurable composition. When the photosensitizer is included in an amount within the above numerical range, the photosensitizer is excited to help initiate the photoinitiator. Specifically, the anthracene-based photosensitizer excited by receiving ultraviolet rays of 380 nm or more immediately transfers energy to the photosensitizing aid, and the excited photosensitizing aid transfers energy so that the photoinitiator can be efficiently initiated. Accordingly, it is possible to effectively reach the inside of the hard coating layer, the polymerization rate is also excellent, and the molecular weight of the resulting polymer can be prevented from decreasing. Therefore, there is an advantage of excellent cohesion and adhesion to the polarizer of the hard coating layer to be formed.

The photocurable composition may further include at least one of dyes, pigments, ultraviolet stabilizers, antioxidants, toning agents, reinforcing agents, fillers, antifoaming agents, surfactants, and plasticizers, if necessary.

The photocurable composition preferably has a glass transition temperature of 90° C. or more and 130° C. or less after curing, and may be 100° C. to 130° C. When the glass transition temperature is in the numerical range as described above, it is possible to implement a hard coating layer having excellent durability even under a high temperature environment.

The present invention is an image display panel; And it provides an image display device including the above-described polarizing plate laminate provided on one or both surfaces of the image display panel.

In the present specification, the image display device may be a liquid crystal display device (LCD), a plasma display device (PDP), and an organic light emitting display device (OLED).

The image display panel may be a liquid crystal panel. In this case, the type of the liquid crystal panel is not particularly limited. For example, a panel of a passive matrix system such as a twisted nematic (TN) type, a super twisted nematic (STN) type, a ferroelectic (F) type, or a polymer dispersed (PD) type; An active matrix type panel such as a two terminal type or a three terminal type; There are a horizontal electric field (IPS; In Plane Switching) panel and a vertical alignment (VA; Vertical Alignment) panel, but are not limited thereto. Further, other components constituting the liquid crystal display device, for example, the types of upper and lower substrates (for example, color filter substrates or array substrates) are not particularly limited.

Hereinafter, examples will be described in detail in order to describe the present specification in detail. However, the embodiments according to the present specification may be modified in various forms, and the scope of the present specification is not construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely describe the present specification to those of ordinary skill in the art.

<Experimental Example>

A polyvinyl alcohol-based polarizer film (manufactured by Japan Synthetic Corporation) prepared in advance with a thickness of 17 μm was supplied with a protective film (PET) for processing on its upper surface under an atmosphere of 25°C, and a protective film (PET, Toyo, Japan) was supplied on the lower surface thereof. (Manufactured by Bosa), and passed through a pair of rolls at a speed of 10 m/min and a pressure of 2 Mpa. At this time, a photocurable adhesive composition was applied between the polarizer film and the protective film to a thickness of about 3 μm using a roll-coating method to form an adhesive layer. In addition, a hard coating layer was formed by applying the photocurable composition of Table 1 below to a thickness of about 6 μm by roll-coating between the polarizer film and the process protective film.

Thereafter, using a fusion lamp, the hard coating layer and the adhesive layer were cured by irradiating ultraviolet rays on the protective film side for the process, thereby preparing a polarizing plate laminate.

After that, the polarizing plate laminate was wound on a roll with a sample length of 5 cm in a direction perpendicular to the winding direction to form a film roll.

<Evaluation method>

1. Peeling resistance and process protective film peeling force test

After storing the polarizing plate laminates of Examples and Comparative Examples at room temperature (25° C.) and 50% relative humidity for 100 hours, a process protection film blocking phenomenon test was conducted to confirm whether the process protection film peeled well. It can be measured using the ASTM 3330 measurement method using a film fast peeler (CBT-4720, Chungbuk Tech). The protective film for a process was peeled with respect to the polarizing plate laminated body at a peeling speed of 30 m/min at an angle of 180 degrees. In order to measure the degree to which the hard coating layer and the process protection film adhere to each other in the process of peeling the process protection film, visually evaluate the degree of transfer of the process protection film onto the hard coating layer after the process protection film is peeled off. I did.

At this time, depending on the appearance of the film, Lv. From 0 Lv. It was evaluated by dividing up to 3.

Lv. 0: When peeling off the protective film for processing, both the hard coating layer and the protective film for processing are peeled cleanly without any abnormality in the appearance (the area of PET remaining on the surface of the hard coating layer is 0%)

Lv. 1: Resistant when peeling, the interface of the process protective film is peeled haze without any damage to the interface of the hard coating layer (the area of PET remaining on the surface of the hard coating layer is 0%)

Lv. 2: Resistant when peeling, the interface of the hard coating layer is damaged, and the interface of the process protective film is peeled off in a haze (PET area remaining on the surface of the hard coating layer is 5% or more)

Lv. 3: The state where the protective film for the process is torn during peeling so that complete peeling is impossible (over 80% of the PET area remaining on the hard coating layer)

2. Heat resistance test of hard coating layer

The polarizer crack growth inhibition test by the hard coating layer was conducted. When manufacturing the polarizing plate laminates of Examples and Comparative Examples, an artificial crack was induced in the polarizer, and then left at a high temperature to observe whether or not cracks were grown. Specifically, in the manufacturing of the polarizing plates of Examples and Comparative Examples, before laminating the retardation film on the polarizer, the polarizer was scratched with a load of 100 g to cause artificial cracking in the polarizer, and the remaining manufacturing conditions were the same to prepare a polarizing plate laminate. .

The prepared polarizing plate laminate was cut into a width of 120 mm and a length of 100 mm, and then left at 80° C. for 100 to 300 hours or more, and then it was observed whether cracks were opened due to shrinkage of the polarizer and light leaked, and the initial total number of cracks (C1 ) By calculating the number of cracks (C2) that leaks light compared to), the incidence rate of cracks in the polarizing plate was derived. Specifically, 200 initial cracks were generated, and the number of cracks leaking light among the initial cracks was calculated.

Crack incidence rate: Number of cracks leaking light/number of initial total cracks x 100(%)

3. Measurement of dynamic thermal properties of hard coating layer

A specimen having the same composition as the hard coating layer of the polarizing plate laminate was prepared and the dynamic thermal properties of the hard coating layer were analyzed. At this time, a dynamic mechanical analysis (DMA) of TA Instruments was used, and the storage modulus (Mpa) and loss modulus (Mpa) were measured while increasing the temperature.

The value obtained by dividing the storage modulus by the loss modulus was defined as the loss tangent modulus tanδ, and the temperature when the loss tangent modulus tanδ was the maximum value was measured and recorded as Tmax.

In addition, the temperature at the point where the slope of the storage modulus rapidly changes was recorded as the glass transition temperature (Tg), and the storage modulus (E') at 80°C was measured.

4. Measurement of peel force between hard coating layer and polarizer

The peel force between the hard coating layer and the polarizer was measured by an ASTM standard cross-cut tape test according to measurement standard D3359-87.

division Kinds Example Comparative example One 2 3 4 5 6 7 One 2 3 Polarizer laminate Hard coating layer composition (A) 70 55 65 35 45 40 50 60 80 65 (B) 0 20 0 20 20 0 0 20 0 20 (C) 20 15 20 15 15 20 20 15 20 15 (D) 10 10 15 30 20 40 30 5 Not included Not included (E1) 2.64 2.64 2.64 2.64 2.64 2.64 2.64 2.64 2.64 2.64 (E2) 1.05 1.05 1.05 1.05 1.05 1.05 1.05 1.05 1.05 1.05 Hard coating layer thickness Unit: ㎛ 6 6 6 6 6 6 6 6 6 6 Property evaluation One Peeling resistance Lv.1 Lv.1 Lv.0 Lv.0 Lv.0 Lv.0 Lv.0 Lv.2 Lv.3 Lv.0 Peeling power of process protective film
(gf/5cm) 30 35 19 18 24 12 15 100 Fracture 130 2 Crack incidence rate (%) 0 0 0 5 0 10 0 0 0 0 3 maximum value of tanδ 0.52 Unmeasured 0.48 0.35 Unmeasured 0.3 0.32 0.54 0.46 0.56 Tmax 127 Unmeasured 125 98 Unmeasured 108 115 126 145 127 E'(@80℃) 2,243 Unmeasured 2,228 1,380 Unmeasured 1,073 1,680 2,028 2,324 2,025 Tg(℃) 106 Unmeasured 102 76 Unmeasured 77 91 105 112 107 4 Peeling force 5B 5B 5B 5B 5B 5B 5B 5B 5B 5B

(E1): 광개시제(Irgacure 250, BASF사 제조)
(E2): 광개시제(ITX: Isopropyl thioxanthone)

(A) 내지 (E)의 수치값은 각 성분의 중량비를 나타냄.
(E1) 내지 (E2)의 수치값은 (A) 내지 (D)의 총 중량에 대한 각 성분의 중량비를 의미함.(A): First epoxy compound (3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate, brand name: CEL-2021P, manufactured by Daicel)
(B): Second epoxy compound (1,4-cyclohexanedimethanol diglycidyl ether, trade name: LD-204)
(C): Oxetane compound (3-ethyl-3-[(3-ethyloxetan-3-yl)methoxymethyl]oxetane, brand name: OXT-221, manufactured by Doagosei)
(D): Polysiloxane compound: (trade name: KR-470, manufactured by Shin-Etsu)
KR-470 structure

(E1): photoinitiator (Irgacure 250, manufactured by BASF)
(E2): photoinitiator (ITX: Isopropyl thioxanthone)

The numerical values of (A) to (E) represent the weight ratio of each component.
The numerical values of (E1) to (E2) refer to the weight ratio of each component to the total weight of (A) to (D).

From the above results, when the hard coating layer does not contain a polysiloxane compound (Comparative Examples 2 and 3), it was confirmed that the peel force between the hard coating layer and the process protective film exceeded 50 gf/5 cm. On the other hand, when the hard coating layer contains a polysiloxane compound (Examples 1 to 7), it was confirmed that the peel force between the hard coating layer and the process protective film was as low as 50 gf/5 cm or less. In addition, the hard coating layer was polysiloxane Even if the compound was included, it was confirmed that the effect improvement by the polysiloxane compound was insignificant when the content was too low (Comparative Example 1).

Claims (11)

Polarizer;
A hard coating layer provided on one or both sides of the polarizer; And
Including a protective film for the process provided on the hard coating layer,
The hard coating layer contains a polysiloxane compound,
The polarizing plate laminate that the peeling force between the hard coating layer and the process protective film is 50 gf/5cm or less at a peeling angle of 180 degrees and a peeling speed of 30 m/min. The method according to claim 1,
The peeling force between the hard coating layer and the polarizer is 4B or more as measured by the ASTM standard cross-cut tape test according to measurement standard D3359-87. The method according to claim 1,
The polarizing plate laminate in which the hard coating layer is provided directly on one or both sides of the polarizer. The method according to claim 1,
The maximum value of the loss tangent coefficient tanδ of the hard coating layer is 0.6 or less. The method according to claim 1,
The maximum value of the loss tangent coefficient tanδ of the hard coating layer is a polarizing plate laminate that appears in a temperature range of 90°C to 120°C. The method according to claim 1,
A polarizing plate laminate having a thickness of the hard coating layer of 5 µm to 15 µm. The method according to claim 1,
The polysiloxane compound is a polarizing plate laminate having a cyclic polysiloxane structure. The method according to claim 1,
The amount of the polysiloxane compound is 6 parts by weight or more and 50 parts by weight based on 100 parts by weight of the hard coating layer. The method according to claim 1,
The hard coating layer is a polarizing plate comprising a cured product of a cationic photocurable composition. The method according to claim 1,
The hard coating layer is a polarizing plate laminate comprising a cured product of a photocurable composition containing an epoxy compound and an oxetane compound. An image display panel; And
An image display device comprising the polarizing plate laminate according to any one of claims 1 to 10 provided on one or both surfaces of the image display panel.

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