TWI596387B - Surface-treated laminated film and polarising plate using it - Google Patents

Description

Surface treatment laminated film and polarizing plate using surface treated laminated film

The present invention relates to a surface treated laminated film in which a multilayer laminated film is subjected to surface treatment. Further, the present invention relates to a polarizing plate obtained by laminating a surface of a polarizing film as a protective film.

In recent years, liquid crystal display devices which are small in power consumption, can be operated at a low voltage, and are light and thin have been widely used in information display devices such as mobile phones, mobile information terminals, screens for computers, and televisions. Information display devices like this have been required to be reliable in extremely harsh environments depending on the application. For example, a liquid crystal display device for a car navigation system may have a very high temperature and humidity inside the vehicle, and the required temperature and humidity conditions are higher than those for a television or a personal computer. To be more demanding. Therefore, in a liquid crystal display device, a polarizing plate used for display can be used in a liquid crystal display device which is required to be used under such severe temperature and/or humidity conditions, and also for a polarizing plate constituting the same. It is required to have high durability.

The polarizing plate has a structure in which a transparent protective film is laminated on both surfaces or a single surface of a polarizing film made of a polyvinyl alcohol-based resin which is adsorbed and has a dichroic dye. In addition, in such a protective film, cellulose triacetate has been widely used, and it has been bonded to a polarizing film through a bonding agent composed of an aqueous solution of a polyvinyl alcohol-based resin. However, a polarizing plate having a protective film composed of cellulose triacetate is laminated because of the penetration of cellulose triacetate When the humidity is high so that it is used for a long period of time in a high-humidity heat environment, there is a case where the polarizing performance is lowered and the protective film and the polarizing film are peeled off.

Therefore, even now, an acrylic resin film having a lower moisture permeability than the cellulose triacetate film has been tried as a protective film for a polarizing plate. For example, Japanese Laid-Open Patent Publication No. 2011-123169 (Patent Document 1) discloses a polarizing plate comprising an active energy ray-curable resin composition containing an oxetane compound and a cationic polymerization initiator as a bonding agent. An acrylic resin film having a longitudinal shrinkage ratio of 0.5% or more when heated at 100 ° C for 10 minutes was laminated on a polarizing film made of a polyvinyl alcohol-based resin. As described above, the acrylic resin film having a low moisture permeability is used as a protective film for a polarizing plate, and it is expected that the moisture resistance of the polarizing plate can be improved.

However, it is known that the acrylic resin film has poor toughness and is easily broken. Further, when a polarizing plate having an acrylic resin film as a protective film is produced, when the acrylic resin film is broken, there is a cracked particle contamination process. After that.

In JP-A-2012-18383 (Patent Document 2), it has been proposed to improve the punching resistance at the time of forming a film and the film forming property at the time of forming a film by blending rubber elastomer particles with an acrylic resin. Further, the smoothing agent is further blended to suppress the crimping of the film when the film is wound into a cylindrical shape. The acrylic resin film in which the rubber elastic particles are blended can improve the impact resistance and suppress cracking as described above. However, when the content of the rubber elastomer particles is increased, the elastic modulus of the film is lowered, so that The heat resistance of the polarizing plate is reduced.

Further, although the surface-treated resin film may be used as a protective film for a polarizing plate, even an acrylic resin film in which rubber elastomer particles are blended may be easily broken by surface treatment. . Therefore, in the case of the acrylic resin film, it is a major problem to prevent cracking when the polarizing film is bonded. For example, Japanese Laid-Open Patent Publication No. 2012-121144 (Patent Document 3) discloses an acrylic resin film obtained by blending rubber elastomer particles and formed by melt extrusion, and the mechanical extrusion direction (MD) thereof. The absorption energy of the punching energy based on the Charpy impact test is 187 kJ/m ² , and the absorption energy in the direction perpendicular to the MD (TD) is 229 kJ/m ² , and relatively, due to the formation of one of them In the surface-treated antiglare layer, the MD absorption energy of the MD is 5 kJ/m ² and the TD absorption energy is 8 kJ/m ² . Therefore, in this document, it is proposed to use a surface of an acrylic resin film which has been subjected to such a surface treatment as a representative example, and a base film which has a absorbing energy of less than 50 kJ/m ² based on a Charpy impact test. The surface protective film is such that the enthalpy absorption energy based on the Charpy impact test in the bonded state becomes 50 kJ/m ² or more, thereby making it difficult to rupture and stably bonding the polarizing film.

Although it becomes difficult to break when the surface protective film is bonded as such, there is still a problem that the film is broken and the steps are increased to increase the cost in the step of bonding the surface treatment protective film.

The present invention has been made in view of the above circumstances, and it is an object of the invention to provide a laminated film which is not easily broken by surface treatment using an acrylic resin film as a base. Another object of the present invention is to provide a laminated film which can be stably operated while bonding another film including a polarizing film to an acrylic resin film substrate.

Still another object of the present invention is to provide a protective film which uses a surface-treated laminated film which is difficult to be broken as a polarizing film, thereby ensuring a polarizing plate which produces stability.

The present inventors have found that by laminating an acrylic resin layer on one or both sides of the ductile polycarbonate resin layer, even after surface treatment with the acrylic resin layer, the film becomes difficult to be broken, and Based on this cognitive finding, various review studies have been conducted further, and the present invention has been completed.

That is, according to the present invention, there is provided a surface-treated laminated film which is a surface-treated laminated film having a polycarbonate resin layer, an acrylic resin layer and a surface treatment layer, which is attached thereto The acrylic resin layer is laminated on one surface or both sides of the polycarbonate resin layer, and when the acrylic resin layer is laminated on one surface of the polycarbonate resin layer, the surface treatment layer is formed in acrylic acid. In the case where the acrylic resin layered layer is on both surfaces of the polycarbonate resin layer, the surface treatment layer is formed on one side of the acrylic resin layer. On the surface opposite to the polycarbonate resin layer; the surface treatment layer described above has H or a pencil hardness which is harder than H; the above polycarbonate resin layer and the acrylic resin laminated on one or both sides thereof The laminate has a film thickness of 35 μm to 100 μm and an internal haze of 5% or less; and the thickness of the polycarbonate resin layer is 2% of the total film thickness of the polycarbonate resin layer and the acrylic resin layer. 45%; the thickness of the acrylic resin layer in which the surface treatment layer is formed is 30 μm or more.

In the surface-treated laminated film, the acrylic resin layer is preferably composed of an acrylic resin containing a rubber elastomer particle having an average particle diameter of 10 nm to 300 nm in a proportion of 30% by weight or less based on the total amount of the total. The object is formed. Further, the surface-treated laminated film may be one having a press strength of 20 N or more.

These surface-treated laminated films are suitably used as a protective film for a polarizing film composed of a polyvinyl alcohol-based resin which adsorbs a dichroic dye. In this case, it is preferable that the polycarbonate resin layer and the acrylic resin layer which is laminated on one surface or both surfaces have an in-plane retardation value of 100 nm or less in total.

Further, according to the present invention, there is also provided a polarizing plate which is formed by laminating a surface-treated laminated film of any of the above, a polarizing film composed of a polyvinyl alcohol-based resin which adsorbs a dichroic dye, and a transparent resin. The protective film; wherein the polarizing film is disposed opposite to a surface of the surface-treated laminated film opposite to the surface-treated layer.

In the polarizing plate, the surface-treated laminated film and the protective film may be adhered to the polarizing film by a cured layer that transmits the active energy ray-curable bonding agent. Further, the protective film may have a function of a retardation film.

The single-layer film of the surface-treated acrylic resin is easily brittle and easily broken, but the surface-treated laminated film of the present invention in which the polycarbonate resin layer is laminated thereon becomes a non-breakable material. . Therefore, it is possible to improve the bonding with other layers, for example, the production stability when the polarizing film is bonded, and it is industrially advantageous to manufacture a functional film which is laminated with other layers, for example, a polarizing plate.

10‧‧‧Surface treatment laminated film

12‧‧‧First acrylic resin layer

13‧‧‧Second acrylic resin layer

15‧‧‧Polycarbonate resin layer

16‧‧‧Laminated film

18‧‧‧Surface treatment layer

20‧‧‧Polar plate

22‧‧‧Polarized film

23,24‧‧‧Adhesive layer

26‧‧‧Transparent resin film

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a preferred aspect of a surface-treated laminated film according to the present invention.

Fig. 2 is a schematic cross-sectional view showing still another preferred aspect of the surface-treated laminated film according to the present invention.

Fig. 3 is a schematic cross-sectional view showing a preferred embodiment of a polarizing plate using the surface-treated laminated film according to the present invention.

Fig. 4 is a schematic cross-sectional view showing still another preferred embodiment of a polarizing plate using the surface-treated laminated film according to the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. The surface-treated laminated film 10 of the present invention is a single-layer first acrylic resin layer 12 of the polycarbonate-based resin layer 15 as shown in Fig. 1, or a polycarbonate system as shown in Fig. 2 The first acrylic resin layer 12 and the second acrylic resin layer 13 are laminated on both surfaces of the resin layer 15, and the surface treatment layer 18 is formed on the surface of the first acrylic resin layer 12.

[Acrylic resin layer]

Acrylic tree used in the first acrylic resin layer 12 and the second acrylic resin layer 13 The fat is typically a methacrylic resin. The methacrylic resin is a polymer mainly composed of methacrylate; it may be a single polymer of methacrylate, or may be 50% by weight or more of methacrylate and 50% by weight or less of monomers other than the others. Copolymer. Here, the methacrylate is usually an alkyl ester using methacrylic acid.

The preferred monomer composition of the methacrylic resin is 50% by weight to 100% by weight based on the total monomer, and the alkyl acrylate is 0% by weight to 50% by weight. The monomer is 0% by weight to 49% by weight; more preferably, the alkyl methacrylate is 50% by weight to 99.9% by weight, and the alkyl acrylate is 0.1% by weight to 50% by weight, and the monomers other than 0% by weight to 49% by weight.

Here, examples of the alkyl methacrylate are, for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, etc.; The carbon number is usually from 1 to 8, preferably from 1 to 4. Among them, methyl methacrylate is preferably used.

Further, examples of the alkyl acrylate include, for example, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc., and the alkyl group has a carbon number of usually 1 to 8, preferably 1~4.

Further, the monomer other than the alkyl methacrylate and the alkyl acrylate may be a monofunctional monomer having one polymerizable carbon-carbon double bond in the molecule, or may have at least two polymerizable groups in the molecule. A polyfunctional monomer having a carbon-carbon double bond; however, it is preferred to use a monofunctional monomer. Examples of the monofunctional monomer include, for example, a styrenic monomer such as styrene, α-methylstyrene or vinyltoluene, a cyanated alkenyl group such as acrylonitrile or methacrylonitrile. , acrylic acid, methacrylic acid, anhydrous maleic acid, N-substituted horse onymine, and the like. Further, examples of the above polyfunctional monomer include, for example, a polyvalent alcohol such as ethylene glycol dimethacrylate, butanediol dimethacrylate or trimethylolpropane triacrylate. a saturated carboxylic acid ester, an allyl acrylate, an allyl methacrylate or an allyl cinnamate, an alkenyl ester of an unsaturated carboxylic acid, a diallyl phthalate, a diallyl maleate, Triallyl cyanurate, A polyalkenyl ester of a polybasic acid such as triallyl cyanurate or an aromatic polyalkenyl compound such as divinylbenzene.

The alkyl methacrylate, the alkyl acrylate, and the other monomers exemplified herein may be used in combination of two or more kinds as needed.

In the present invention, an acrylic resin composition obtained by blending rubber elastomer particles with an acrylic resin is preferably used. In the acrylic resin composition, in order to prevent a decrease in the modulus of elasticity, it is preferred that the content of the rubber elastomer particles is small. On the other hand, in order to improve the film formability, it is preferred to blend a plurality of rubber elastomer particles. By. Therefore, it is preferable that the film forming property and the elastic modulus of the film together determine the blending amount of the rubber elastomer particles. The rubber elastomer particles used for this purpose contain particles of a layer exhibiting rubber elasticity. Such rubber elastomer particles may be particles composed only of a layer exhibiting rubber elasticity, or particles having a multilayer structure having a layer exhibiting rubber elasticity and having another layer. The rubber elastic body may be, for example, an olefin rubber elastic polymer, a diene rubber elastic polymer, a styrene-diene rubber elastic copolymer, an acrylic rubber elastic polymer or the like. Among them, from the viewpoint of surface hardness, light resistance, and transparency of the surface-treated laminated film, an acrylic rubber elastic polymer is preferably used.

The acrylic rubber elastic polymer may be a polymer mainly composed of an alkyl acrylate. This may be a single polymer of an alkyl acrylate; it may be a copolymer of 50% by weight or more of an alkyl acrylate and 50% by weight or less of a monomer other than the others. The alkyl acrylate is usually a compound having 4 to 8 carbon atoms using an alkyl group. In the case of copolymerizing a monomer other than an alkyl acrylate, for example, it may be an alkyl methacrylate such as methyl methacrylate or ethyl methacrylate such as styrene and a styrene monomer such as an alkyl styrene, a monofunctional monomer such as an unsaturated nitrile such as acrylonitrile or methacrylonitrile; and an allyl (meth) acrylate and (meth) acrylate An alkenyl ester of an unsaturated carboxylic acid such as methyl allyl ester, a diallyl ester of a dibasic acid such as diallyl maleate, or an alkanediol di(meth)acrylate A polyfunctional monomer such as a glycol-based unsaturated carboxylic acid diester.

The rubber elastomer particles are preferably particles having a multilayer structure of a layer of an acrylic rubber elastic polymer. Specifically, for example, it may be a two-layer structure having a hard polymer layer mainly composed of an alkyl methacrylate on the outer side of the acrylic rubber elastic polymer; in addition, an acrylic rubber elastic polymer The inside has a three-layer structure of a hard polymer layer mainly composed of an alkyl methacrylate. An example of a monomer composition constituting a polymer having an alkyl methacrylate as a main component of a hard polymer layer formed on the outer side or the inner side of the acrylic rubber elastic polymer, which is the acrylic resin previously listed. Examples of the monomer composition of the polymer having a methacrylic acid alkyl ester as a main example are the same; it is particularly preferable to use a monomer composition mainly composed of methyl methacrylate. The acrylic rubber elastomer particles having a multilayer structure of this type can be produced, for example, by the method described in Japanese Patent Publication No. 55-27576.

The average particle diameter of the rubber elastomer particles is preferably in the range of 10 nm to 350 nm. Thereby, since unevenness is formed only on the surface of the film, smoothness can be improved. The average particle diameter of the rubber elastomer particles is preferably 30 nm or more, more preferably 50 nm or more, and more preferably 300 nm or less, more preferably 280 nm or less.

The average particle diameter of the acrylic rubber elastomer particles of the multilayer structure was measured by the following procedure. That is, rubber rubber particles such as this are mixed in an acrylic resin and thinned, and when the cross section is dyed with an aqueous solution of cerium oxide, it is observed that only the rubber elastic polymer layer is colored, almost round. The acrylic resin of the shape and the mother layer was not dyed. Therefore, a section of the film dyed by such a method is prepared into a sheet by a microtome or the like, and observed by an electron microscope. Then, 100 dyed rubber elastic particles were unintentionally extracted, and the respective particle diameters were calculated, and then the average number of the particles was taken as the average particle diameter. Since the measurement was carried out by such a method, the average particle diameter of the obtained rubber elastomer particles was the number average particle diameter.

In the case where the outermost layer is a hard polymer having methyl methacrylate as a main component, and a rubber elastomer particle containing an acrylic rubber elastic polymer therein, when it is used When the matrix acrylic resin is mixed, the outermost layer of the rubber elastomer particles is mixed with the matrix acrylic resin. Therefore, when the cross section was dyed with cerium oxide and observed by an electron microscope, particles of the rubber elastic particle in a state not including the outermost layer were observed. Specifically, in the case of using a rubber elastic particle having a two-layer structure in which the inner layer is an acrylic rubber elastic polymer and the outer layer is a hard polymer mainly composed of methyl methacrylate, the inner layer can be observed. The acrylic rubber elastic polymer portion is dyed into a single-layer structure; in addition, the innermost layer is a hard polymer mainly composed of methyl methacrylate, and the intermediate layer is an acrylic rubber elastic polymer. In the case where the outermost layer is a rubber elastomer particle having a three-layer structure of a hard polymer mainly composed of methyl methacrylate, it can be observed that the central portion of the innermost layer is not dyed, and only the intermediate layer is A two-layer structure particle in which an acrylic rubber elastic polymer portion is dyed. In the present invention, when the acrylic rubber elastomer particles having a multilayer structure are used as the rubber elastic particles, the average particle diameter of the acrylic rubber elastic polymer portion is the average particle diameter of the rubber elastic particles.

The rubber elastomer particles are preferably blended at a ratio of 30% by weight or less, more preferably 25% by weight or less, more preferably 25% by weight or less based on the total amount of the acrylic resin described above, and more preferably 20% by weight or less. When the amount is too large, the surface hardness of the obtained surface-treated laminated film becomes low, which is not preferable. As described above, in order to prevent a decrease in the elastic modulus of the acrylic resin, it is preferred that the content of the rubber elastomer particles is small, but on the other hand, in order to improve the film formability of the film and the resistance of the obtained surface-treated laminated film. In order to improve the smoothness by forming irregularities only on the surface of the film, it is preferred to blend the rubber elastomer particles in the proportions previously described. The amount of the rubber elastomer particles is preferably 3% or more, and more preferably 5% or more, based on the total amount of the acrylic resin described above. Further, in the present invention, in the case where the particles exhibiting the rubber elastic layer and having the multilayer structure of the other layer are rubber elastic particles, the portion composed of the rubber elastic layer and the inner layer thereof is used. The weight is taken as the weight of the rubber elastomer particles. For example, in the case of using the above-described three-layer structure of the acrylic rubber elastomer particles, the intermediate layer is used. The total weight of the acrylic rubber elastic polymer portion and the hard polymer portion mainly composed of methyl methacrylate as the innermost layer is the weight of the rubber elastic particles. When the above-mentioned three-layer structure of the acrylic rubber elastomer particles is dissolved in acetone, the acrylic rubber elastic polymer portion of the intermediate layer and the hard polymer having the innermost layer of methyl methacrylate as the main component Since the part remains insoluble and remains together, the ratio of the total weight of the intermediate layer to the innermost layer which is occupied by the acrylic rubber elastomer particles having a three-layer structure can be easily obtained.

A predetermined amount of the rubber elastomer particles may be blended in the acrylic resin, and a small amount of a smoothing agent may be further blended to prepare a raw material for the surface-treated laminated film. When the smoothing agent is blended, it is possible to prevent the crimping of the acrylic resin film when it is wound into a cylindrical shape, thereby improving the package shape in the wound state. The smoothing agent may be any one having a function of improving the smoothness of the surface of the acrylic resin film. Examples of the compound having a function like this include, for example, a stearic acid compound, a propylene oxide compound, an ester compound, and the like. Among them, a stearic acid-based compound is preferably used as a smoothing agent.

As an example of the stearic acid compound as a smoothing agent, in addition to stearic acid itself, for example, it may be, for example, methyl stearate and ethyl stearate, stearic acid monoglyceride or the like. Stearate; decylamine stearate; sodium stearate and calcium stearate, zinc stearate, lithium stearate, magnesium stearate, etc.; such as 12-hydroxystearate 12-hydroxystearic acid such as acid, sodium 12-hydroxystearate, zinc 12-hydroxystearate, calcium 12-hydroxystearate, lithium 12-hydroxystearate, magnesium 12-hydroxystearate And its metal salts and so on. Among them, preferred is stearic acid.

The blending amount of the smoothing agent may be 0.15 parts by weight or less based on 100 parts by weight of the total of the acrylic resin and the rubber elastomer particles, and is preferably 0.1 part by weight or less, more preferably 0.07 part by weight. The following range. When the blending amount of the smoothing agent is too large, there is a possibility that the smoothing agent bleeds out from the film to lower the transparency of the film.

Acrylic resin blended with rubber elastomer particles and, if desired, a smoothing agent The composition may be any composition as long as it is the composition described so far, and the production method thereof is arbitrary. For example, first, rubber elastomer particles are produced, and when rubber elastomer particles are present, a monomer which is a raw material of the acrylic resin is polymerized to form a matrix acrylic resin, and the acrylic resin is blended. a composition of the rubber elastomer particles, by adding a predetermined amount of a smoothing agent thereto as desired; mixing the rubber elastomer particles and the acrylic resin in a predetermined ratio, and adding a predetermined amount of a smoothing agent thereto as desired, A method of mixing by melt kneading or the like.

Further, the acrylic resin may contain various additives such as a fluorescent whitening agent, a dispersing agent, a heat stabilizer, a photostabilizer, an ultraviolet absorber, an infrared absorber, an antistatic agent, and an antioxidant, as needed.

The ultraviolet absorber is a compound capable of absorbing ultraviolet rays having a wavelength of 400 nm or less. When a surface-treated laminated film is used as the protective film of the polyvinyl alcohol-based polarizing film, the durability of the polarizing plate obtained by bonding the protective film to the polarizing film can be improved by blending the ultraviolet absorber. Effect. As the ultraviolet absorber, a well-known thing such as a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, or an acrylonitrile-based ultraviolet absorber can be used. Specific examples include, for example, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl) Phenol], 2-(2'-hydroxy-3'-tertiary-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2,4-di-tertiary-butyl- 6-(5-chlorobenzotriazol-2-yl)phenol, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'- Tetrahydroxybenzophenone and the like. Among these, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol] It is one of the preferred UV absorbers. The blending amount of the ultraviolet absorber may be selected from a range in which the transmittance of the surface-treated laminated film at a wavelength of 370 nm or less is 10% or less, and is preferably 5% or less, more preferably 2% or less. The method of allowing the acrylic resin to contain the ultraviolet absorber may be any method. For example, the ultraviolet absorber may be previously blended in an acrylic resin and pelletized, and formed by melt extrusion or the like. A method of forming a film; a method of directly adding an ultraviolet absorber during melt extrusion molding, and the like.

The infrared ray absorbing agent is a compound capable of absorbing infrared rays having a wavelength of 800 nm or more. For example, it may be a nitroso compound, a metal sulphate of a nitroso compound, a cyano compound, a quaternary lanthanide compound, a thionickel salt compound, a guanidinium compound, a naphthyl cyanide compound, or a triarylmethane. a compound, an indium compound, a diindium compound, a naphthoquinone compound, an anthraquinone compound, an amine compound, an ammonium salt compound, carbon black, indium tin oxide, antimony tin oxide, a metal belonging to Group 4A of the periodic table. An oxide, an oxide, a carbide or a boride of a metal belonging to Group 5A or Group 6A. As such an infrared ray absorbing agent, it is preferable to select all of the infrared ray (light having a wavelength of about 800 nm to 1100 nm), and it is also possible to use two or more types. The blending amount of the infrared ray absorbing agent can be appropriately adjusted so that the light transmittance of the surface-treated laminated film at a wavelength of 800 nm or more becomes 10% or less.

As shown in Fig. 2, when the first acrylic resin layer 12 and the second acrylic resin layer 13 are laminated on both surfaces of the polycarbonate resin layer 15, the rubber elastomer particles and the aforementioned additives can be obtained. The content in each layer is different from each other. For example, when the content of the rubber elastic particles of the first acrylic resin layer 12 is made small, it is advantageous in that the pencil hardness can be improved. On the other hand, when the content of the rubber elastic particles of the second acrylic resin layer 13 is increased, it is advantageous in improving the punching resistance, the film forming property, and the bondability with the polarizing film.

[Polycarbonate resin layer]

The polycarbonate resin used in the polycarbonate resin layer 15 may be, for example, a reaction obtained by reacting divalent phenol and a carbonylating agent by an interfacial polycondensation method or a melt transesterification method. A product obtained by polymerizing a carbonate polymer by a solid phase transesterification method or the like, and polymerizing a cyclic carbonate compound by a ring-opening polymerization method.

The divalent phenol, for example, may be hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)methane, bis{(4-hydroxy-3,5) -Dimethyl)phenyl}methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-double (4-hydroxyphenyl)propane (commonly known as double Phenol A), 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2,2-bis{(4-hydroxy-3,5-dimethyl)phenyl}propane, 2 , 2-bis{(4-hydroxy-3,5-dibromo)phenyl}propane, 2,2-bis{(3-isopropyl-4-hydroxy)phenyl}propane, 2,2-dual { (4-hydroxy-3-phenyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 2,2-dual (4 -hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-double ( 4-hydroxyphenyl)-4-isopropylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 9,9-bis (4- Hydroxyphenyl)anthracene, 9,9-bis{(4-hydroxy-3-methyl)phenyl}anthracene, α,α'-bis(4-hydroxyphenyl)-o-diisopropylbenzene, α , α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene, α,α'-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,3-double (4 -hydroxyphenyl)-5,7-dimethyl adamantane, 4,4'-dihydroxydiphenylanthracene, 4,4'-dihydroxydiphenylarylene, 4,4'-dihydroxydiphenyl Base sulfide, 4,4'-dihydroxydiphenyl ketone, For the 4,4'-dihydroxydiphenyl ether or 4,4'-dihydroxydiphenyl ester, two or more kinds thereof may be used as needed.

Among them, preferred are bisphenol A, 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,2-dual (4 -hydroxyphenyl)-4-methylpentane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and α,α'-bis(4-hydroxybenzene Divalent phenol selected from the group consisting of -m-diisopropylbenzene, alone or in combination of two or more; particularly preferred is bisphenol A alone, and 1,1-bis(4-hydroxyphenyl) -3,3,5-trimethylcyclohexane with, bisphenol A, 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane and α,α'-bis(4-hydroxyl One or more divalent phenols selected from phenyl)-m-diisopropylbenzene are used in combination.

The carbonylating agent may, for example, be a carbonyl halide such as phosgene, a carbonate such as diphenyl carbonate, or a haloformate such as a dihalo valinate of divalent phenol. Etc. As needed, two or more of these may be used.

Further, the same additive as described in the item of the acrylic resin layer may be blended in the polycarbonate resin.

[Laminated film]

The first acrylic resin layer 12 is formed on one surface of the polycarbonate resin layer 15 composed of the polycarbonate resin described above, or the first acrylic resin is formed on both surfaces of the polycarbonate resin layer 15. The layer 12 and the second acrylic resin layer 13 can provide the laminated film 16 of the substrate of the surface-treated laminated film 10 of the present invention. The method for molding the laminated film 16 can be appropriately selected. For example, it is possible to effectively use an extruder to melt individual resins, and to use a feed block method or a multi-manifold method for lamination co-extrusion molding. And a method in which a polycarbonate resin is thinned by an extrusion molding method or the like, and an acrylic resin is dissolved in a solvent as needed to be applied to the surface of the film. Among these, it is preferred to use a coextrusion molding method.

The coextrusion molding method bonds the molten resin to a cylinder or a belt for film formation. The number and arrangement of the cylinders or belts are not particularly limited. However, the molten resin is placed between two metal cylinders or brought into contact and passed through a metal cylinder and a metal belt. The method of printing the surface shape of the cylinder or the belt is preferable because it can improve the surface precision of the surface of the film and increase the surface treatment property. Alternatively, it is also suitable to use a metal cylinder and a metal cylinder having elasticity to hold the molten resin to bring the molten resin into contact with both surfaces, since it is possible to reduce unevenness during molding, and to reduce strength and heat shrinkage. A film with an opposite orientation. The metal elastic cylinder may be, for example, a cylindrical metal film having a shaft cylinder, an outer peripheral surface disposed to cover the shaft cylinder and contacting the molten resin, and the metal cylinder in the equiaxed cylinder and the metal film. A person who is controlled by a temperature controlled by water or oil, or a metal belt wound around the surface of the rubber cylinder is enclosed.

The laminated film 16 thus obtained preferably has a thickness of 35 μm to 100 μm, preferably 40 μm to 95 μm, more preferably 45 μm to 90 μm.

The film thickness of the polycarbonate resin layer 15 is set to 2% to 45% of the total film thickness of the laminated film 16. The ratio of the film thickness of the polycarbonate resin layer 15 to the total film thickness of the laminated film 16 is preferably 5% or more, more preferably 10% or more, and more preferably 40% or less. . When the ratio of the film thickness of the polycarbonate resin layer 15 in the total film thickness of the laminated film 16 is too small, The laminated film 16 is easily brittle and easily broken. On the other hand, when the ratio of the film thickness of the polycarbonate resin layer 15 in the film thickness of the laminated film 16 is too large, the surface hardness becomes insufficient.

As shown in FIGS. 1 and 2, a surface treatment layer 18 is formed on the surface of the first acrylic resin layer 12. The thickness of the first acrylic resin layer is 30 μm or more, preferably 35 μm or more, and more preferably 40 μm or more. The thicker the thickness of the first acrylic resin layer, the higher the surface hardness of the obtained surface-treated laminated film, which is preferable.

As shown in Fig. 2, when the first acrylic resin layer 12 and the second acrylic resin layer 13 are laminated on both surfaces of the polycarbonate resin layer 15, and the three acrylic layers are formed, the first acrylic resin layer 12 and The film thickness of the second acrylic resin layer 13 may be the same or different. In the case where the thicknesses thereof are different, when the first acrylic resin layer 12 on which the surface treatment layer 18 is formed is thickened, it is advantageous because the surface hardness becomes high. In this case, the film thickness of the second acrylic resin layer 13 is preferably 2 μm or more in order to maintain strength. On the other hand, in the case where the film thicknesses are the same, the film thickness of the polycarbonate resin layer 15 which is occupied by the entire film thickness of the laminated film 16 is preferably from the viewpoint of maintaining the surface hardness. 35% or less, and more preferably 30% or less.

The laminated film 16 is required to have high transparency; specifically, the internal haze measured in accordance with JIS K7105-1981 "Test method for optical properties of plastics" is 5% or less. When the internal haze exceeds 5%, the surface-treated laminated film of the present invention is applied to a polarizing plate, and when it is assembled to an image display device, the whiteness is lowered and the screen is darkened, which is not preferable. The internal haze is preferably 3% or less.

Next, the phase difference value of the laminated film 16 will be described. When the refractive index of the in-plane axis direction of the film is denoted by n _x , the refractive index of the in-plane axial direction (the direction perpendicular to the slow axis in the in-plane) is denoted by n _y , and the thickness is recorded as In the case of d, the in-plane phase difference value Ro is as defined in the following formula (I).

Ro=(n _x -n _y )×d (I)

Applying the surface-treated laminated film 10 of the present invention to optical applications, for example, application In the case of the polarizing plate, the in-plane retardation value Ro at a wavelength of 590 nm is preferably 100 nm or less in the laminated film 16 based on the surface-treated laminated film.

[surface treatment laminated film]

The surface treatment layer 18 is formed on the surface of the first acrylic resin layer 12 of the laminated film 16 to form a surface-treated laminated film 10. As an example of the surface treatment, for example, there is a hard coating treatment for the purpose of preventing surface scratching in a liquid crystal module assembly process. Further, there is also a functional surface treatment such as antistatic treatment. In addition, the antistatic function may be provided by performing surface treatment on the laminated film 16, or may be provided on the other portion of the polarizing plate in which the surface-treated laminated film 10 is assembled, such as an adhesive layer. In addition to the functional surface treatment of the laminated film 16, there are also antireflection treatments and antifouling treatments. In addition, it is also useful for anti-glare treatment for the purpose of improving visibility, preventing external light from being reflected, and reducing interference fringes caused by dryness of the ruthenium and the color filter. When a surface treatment such as this is performed on a single-layer acrylic resin film, it becomes very easy to be broken; whereas, for the single-layer layer of the polycarbonate-based resin layer 16, there is a first acrylic resin layer 12 In the laminated film 16 in which the laminated film 16 in which the first acrylic resin layer 12 and the second acrylic resin layer 13 are laminated on both surfaces of the polycarbonate resin layer 16 is subjected to surface treatment like this, The toughness is improved and the ease of cracking can be suppressed.

<surface treatment layer>

The hard coating layer has a function of increasing the surface hardness of the surface-treated laminated film 10, and can be provided for the purpose of preventing surface scratching or the like. The hard coating layer is shown in the pencil hardness test specified in JIS K 5600-5-4:1999 "General Test Methods for Coatings - Part 5: Mechanical Properties of Coating Films - Section 4: Scratch Hardness (Pencil Method)" H or a value that is harder than H. The material forming such a hard coating layer is generally a material that is hardened by heat and light. For example, it may be an organic hard coating material such as an organic siloxane oxide, a melamine system, an epoxy resin, an acrylic resin, an urethane acrylate or the like, and an inorganic hard coating material such as cerium oxide. Among these, in particular, from the viewpoint of good bondability and excellent productivity, it is preferably an amine group. A formate acrylic and a polyfunctional acrylic hard coating.

The hard coating layer may have various properties such as adjustment of the refractive index, increase in the bending elastic modulus, stabilization of the volume shrinkage ratio, and further improvement of heat resistance, antistatic property, and antiglare property, etc., as desired. filler. Further, the hard coating layer may contain an additive such as an antioxidant, an ultraviolet absorber, a photostabilizer, an antistatic agent, a leveling agent, or an antifoaming agent.

The antistatic layer is provided for the purpose of providing conductivity to the surface of the laminated film 16, and for suppressing the influence of static electricity or the like. For the formation of the antistatic layer, for example, a method of applying a resin composition containing a conductive substance (antistatic agent) can be employed. Specifically, an antistatic hard coating layer can be formed by coexisting the hard coating material used for forming the hard coating layer described above with an antistatic agent.

The antireflection layer is a layer for preventing reflection of external light, and may be provided on the surface of the first acrylic resin 12 of the laminated film 16 directly or through another layer such as a hard coating layer. The surface-treated laminated film 10 provided with the anti-reflection layer preferably has a reflectance of 2% or less for an incident angle of light of a wavelength of 430 nm to 700 nm of 5°, and particularly preferably for the same incident angle of light of a wavelength of 550 nm. The reflectance is 1% or less.

The thickness of the antireflection layer may be from about 0.01 μm to about 1 μm, and more preferably from 0.02 μm to 0.5 μm. The antireflection layer has a refractive index smaller than that of the layer (the laminated film 16 or the hard coating layer, etc.) provided therewith; specifically, a low refractive index layer having a refractive index of 1.30 to 1.45. The low refractive index layer of the film made of an inorganic compound and the high refractive index layer of the film made of an inorganic compound may be formed by alternately laminating a plurality of layers.

The material for forming the low refractive index layer described above is not particularly limited as long as it has a small refractive index. For example, it may be a resin material such as an ultraviolet curable acrylate resin, a doping material in which an inorganic fine particle such as colloidal vermiculite is dispersed in a resin, a sol material containing an alkoxysilane or the like. A low refractive index layer like this can be formed by coating a polymerized polymer The formation may be carried out by coating in the state of a monomer or an oligomer which is a precursor, and then curing by polymerization. Further, in order to provide antifouling properties, individual materials preferably contain a compound having a fluorine atom in the molecule.

The sol material for forming the low refractive index layer is preferably one having a fluorine atom in the molecule. A typical example of a sol material having a fluorine atom in the molecule is, for example, a polyfluoroalkyl alkoxysilane. The polyfluoroalkyl alkoxysilane may, for example, be a compound represented by the following formula; CF ₃ (CF ₂ ) _n CH ₂ CH ₂ Si(OR) ₃ where R represents an alkyl group having 1 to 5 carbon atoms; Indicates an integer from 0 to 12. Among them, n in the above formula is preferably a compound of 2 to 6.

The perfluoroalkyl alkane gas, specifically, for example, may be a compound of the kind exemplified below.

3,3,3-trifluoropropyltrimethoxydecane, 3,3,3-trifluoropropyltriethoxydecane, 3,3,4,4,5,5,6,6,7,7 , 8,8,8-Decafluorooctyltrimethoxydecane, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxy Basear, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyltrimethoxydecane, 3,3 4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyltriethoxydecane, and the like.

The low refractive index layer may be composed of a cured product of a thermosetting fluorine-containing compound or an active energy ray-curable fluorine-containing compound. The kinetic coefficient of friction of the cured product is preferably in the range of 0.03 to 0.15, and the contact angle with respect to water is preferably in the range of 90 to 120. a hardening fluorine-containing compound other than a perfluoroalkyl-containing decane compound (for example, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10 described above, In addition to 10,10-heptadecafluorodecyltriethoxydecane, etc., it may, for example, be a fluoropolymer having a crosslinkable functional group.

A fluoropolymer having a crosslinkable functional group can be obtained by The crosslinkable functional group monomers are co-polymerized together; or by copolymerizing a fluorine-containing monomer with a monomer having a functional group, followed by attaching a crosslinkable functional group to a functional group in the polymer The method of the base compound is manufactured.

The fluorine-containing monomer used herein may, for example, be, for example, fluorinated ethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxo. A fluorinated olefin such as a heterocyclic pentene, or a partially or fully fluorinated alkyl ester derivative of (meth)acrylic acid, or a wholly or partially fluorinated vinyl ether.

a monomer having a crosslinkable functional group or a compound having a crosslinkable functional group, for example, which may be a monomer having a glycidyl group such as glycidyl acrylate or glycidyl methacrylate; a monomer having a carboxyl group such as acrylic acid or methacrylic acid; a monomer having a hydroxyl group such as a hydroxyalkyl acrylate or a hydroxyalkyl methacrylate; allyl acrylate or allyl methacrylate; a monomer having an alkenyl group; a monomer having an amine group; a monomer having a sulfonyl group; and the like.

The material for forming the low refractive index layer may be formed by dispersing an inorganic compound fine particle containing cerium oxide, aluminum oxide, titanium oxide, zirconium oxide, magnesium fluoride or the like in an alcohol solvent because the scratch resistance can be improved. The composition of the sol is composed. The inorganic compound fine particles used for this purpose are preferably those having a small refractive index from the viewpoint of antireflection properties. Such inorganic compound fine particles may be those having voids, and particularly preferably hollow particles of cerium oxide. The average particle diameter of the hollow fine particles is preferably in the range of 5 nm to 2,000 nm, and more preferably in the range of 20 nm to 100 nm. The average particle diameter referred to herein means the average particle diameter of the particles obtained by observation under a transmission electron microscope.

The antifouling layer is provided to provide water repellency, oil repellency, sweat resistance, antifouling property and the like. A suitable material for forming the antifouling layer is a fluorine-containing organic compound. The fluorine-containing organic compound may be, for example, a carbon fluoride, a perfluorodecane, or a polymer compound thereof. The method of forming the antifouling layer may be a physical vapor phase growth method, a chemical vapor phase growth method, a wet coating method, or the like which is represented by vapor deposition and sputtering, depending on the material to be formed. The average thickness of the antifouling layer is usually about 1 nm to 50 nm. Preferably, it is from 3 nm to 35 nm.

The antiglare layer is a layer having a fine uneven shape on the surface, and is preferably formed of the above-described hard coating material.

An anti-glare layer having a fine uneven shape on the surface can be formed by forming a coating film containing organic fine particles or inorganic fine particles on the surface of the laminated film 16, and providing irregularities based on the fine particles; and forming or not After the coating film containing the fine particles or the inorganic fine particles, the film is formed by a method in which a concave-convex shape is formed on the surface, and the uneven shape is transferred (also referred to as an embossing method). The formation of such a coating film can be carried out, for example, by applying a coating liquid composed of a composition in which a layer of the organic thin film is mixed with a curable transparent resin. .

In the case where fine particles are blended to form the antiglare layer, the fine particles are preferably those having an average particle diameter of 0.5 μm to 5 μm and a refractive index difference between transparent resins of 0.02 to 0.2. The haze can be effectively exhibited by using fine particles having an average particle diameter and a refractive index difference between the transparent resins in this range. The average particle diameter of the fine particles can be determined by a dynamic light scattering method or the like. The average particle diameter in this case is a weight average particle diameter.

As the inorganic fine particles for forming the antiglare layer, cerium oxide, colloidal vermiculite, alumina, alumina sol, aluminosilicate, alumina-yttria composite oxide, kaolin, talc, mica, calcium carbonate, phosphoric acid can be used. Calcium, etc. Further, as the organic fine particles, resin particles are generally used, and for example, they may be crosslinked polyacrylic acid particles, methyl methacrylate/styrene copolymer resin particles, crosslinked polystyrene particles, crosslinked polymethyl groups. Methyl acrylate particles, siloxane oxide particles, polyamide particles, and the like.

The transparent resin for dispersing the inorganic fine particles or the organic fine particles is preferably selected from materials having high hardness (hard coating). For the transparent resin, a photocurable resin, a thermosetting resin, an electron beam curable resin, or the like can be used. However, from the viewpoint of productivity and hardness of the obtained film, etc., it is preferred to use a photocurable resin. . Photocurable resin, generally using multi-functional C Oleate. Examples thereof are, for example, a di- or tri-acrylate of trimethylolpropane, a tri- or tetra-acrylate of pentaerythritol, a reaction product of a reaction product of an acrylate having at least one hydroxyl group in a molecule and a diisocyanate. Amino methacrylate and the like. These polyfunctional acrylates may be used alone or in combination of two or more kinds as needed.

Further, a mixture of a polyfunctional urethane acrylate, a polyol (meth) acrylate, and a (meth)acrylic polymer having an alkyl group having two or more hydroxyl groups may be used as the photocurability. Resin. The polyfunctional urethane acrylate constituting the photocurable resin can be produced, for example, by using (meth)acrylic acid and/or (meth)acrylate, a polyol, and a diisocyanate. Specifically, a hydroxy (meth) acrylate having at least one hydroxyl group in the molecule can be prepared by using (meth)acrylic acid and/or (meth) acrylate and a polyol to make it and the diisocyanate The reaction is carried out to produce a polyfunctional urethane acrylate. The polyfunctional urethane acrylate produced by this method itself also forms the photocurable resin previously disclosed. In the production, (meth)acrylic acid and/or (meth)acrylic acid ester may be used alone or in combination of two or more. The polyol and the diisocyanate may be used in the same manner. Use two or more combinations.

The (meth) acrylate which forms one of the raw materials of the polyfunctional urethane acrylate may be a chain or cyclic alkyl ester of (meth)acrylic acid. Specific examples thereof may be, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, (meth)acrylic acid. An alkyl (meth)acrylate such as butyl ester; and a cycloalkyl (meth)acrylate such as cyclohexyl (meth) acrylate.

Further, the polyol which forms one of the other raw materials of the polyfunctional urethane acrylate is a compound having at least two hydroxyl groups in the molecule. For example, it may be ethylene glycol, propylene glycol, 1,3-propanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, 1,4- Butylene glycol, 1,6-hexanediol, 1,9-nonanediol, 1,10-nonanediol, 2,2,4-trimethyl-1,3-pentanediol, 3-methyl Base-1,5-pentanediol, neopentyl glycol ester of hydroxytrihydroxyacetic acid, cyclohexane trimethylol ester, 1,4-cyclohexanediol, Spirodiol, tricyclodecane trimethylol ester, hydrogenated bisphenol A, ethylene oxide addition bisphenol A, propylene oxide addition bisphenol A, trimethylolethane, trimethylol Propane, glycerin, 3-methylpentane-1,3,5-triol, pentaerythritol, dipentaerythritol, tripentaerythritol, glucose, and the like.

The diisocyanate forming another raw material of the polyfunctional urethane acrylate is a compound having two isocyanate groups (-NCO) in the molecule, and various diisocyanates of an aromatic, aliphatic or alicyclic type can be used. Specific examples, for example, may be tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,4-toluene diisocyanate, 4,4'-diphenyl diisocyanate. 1,5-Streptyl diisocyanate, 3,3'-dimethyl-4,4'-diphenyl diisocyanate, xylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4' - Diphenylmethane diisocyanate, and a nuclear hydrogenated product of a diisocyanate having an aromatic ring among these.

The polyfunctional urethane acrylate and the polyol (meth) acrylate constituting the above photocurable resin are (meth) acrylates of a compound having at least two hydroxyl groups in the molecule (ie, a polyol). . Specific examples thereof may be, for example, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1, 6-hexanediol di(meth)acrylate or the like. These polyol (meth) acrylates may be used singly or in combination. The polyol (meth) acrylate preferably contains pentaerythritol triacrylate and/or pentaerythritol tetraacrylate.

Further, such a polyfunctional urethane acrylate, a polyol (meth) acrylate, and a (meth)acrylic polymer having an alkyl group having two or more hydroxyl groups constituting the photocurable resin, It is an alkyl group having two or more hydroxyl groups in one constituent unit. For example, it may be composed of 2,3-dihydroxypropyl (meth)acrylate as a constituent polymer, 2,3-dihydroxypropyl (meth)acrylate, and 2-hydroxyethyl ( The methyl acrylate is a polymer or the like which constitutes a unit.

By using an acrylic photocurable resin such as exemplified above, adhesion to the first acrylic resin layer 12 can be improved, mechanical strength can be improved, and effective prevention can be effectively prevented. Surface scratches.

A photocurable resin like this is combined with a photopolymerization initiator to form a photocurable resin composition. Among the photopolymerization initiators, various substances such as acetophenone type, benzophenone type, benzoin ether type, amine type, and phosphine oxide type are available. An example of a compound classified as a phthalicone photopolymerization initiator, for example, 2,2-dimethoxy-2-phenylethanone (alias: benzyldimethylketal) 2,2-diethoxyacetone, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2 -Methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one or the like. Examples of the compound classified into a benzophenone-based photopolymerization initiator include, for example, benzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, and the like. . Examples of the compound classified into a benzoin ether photopolymerization initiator include benzoin methyl ether and benzoin propyl ether. Examples of the compound classified as an amine photopolymerization initiator are, for example, N,N,N',N'-tetramethyl-4,4'-diaminobenzophenone (alias: Mira Zlot) and so on. Examples of the phosphine oxide photopolymerization initiator include, for example, 2,4,6-trimethylbenzocylidene diphenylphosphine oxide. In addition, a photopolymerization initiator such as a phenol ketone compound or a thioxanthone compound is known.

These photopolymerization initiators are commercially available. Examples of representative commercial products include, for example, "Iru Ka Kua 907", "Iru Ka Kua 184", "Lu Xilin TPO", etc., which are sold by the BASF company in Germany.

In the photocurable resin composition, a solvent may be added as needed. In this case, for example, any organic solvent which can dissolve each component constituting the composition of ethyl acetate, butyl acetate or the like can be used. Of course, it is also possible to use two or more kinds of organic solvents in combination.

Further, the photocurable resin composition may contain a leveling agent; for example, it may be a fluorine-based or a siloxane-based leveling agent. Examples of the oxane-based leveling agent include a reactive siloxane, a polydimethyl siloxane, a polyether modified polydimethyl siloxane, a polymethyl alkyl siloxane, and the like. Preferred among the oxane-based leveling agents are reactive oxiranes and siloxane-based leveling agents. Reactive oxirane The leveling agent can provide smoothness to the surface of the hard coating layer and maintain excellent scratch resistance for a long period of time. Moreover, the film formability can be improved by using a siloxane-based leveling agent.

When a photocurable resin such as the above is used for the formation of the antiglare layer, the inorganic or organic fine particles are dispersed in the respective components constituting the photocurable resin composition described above, and then The resin composition is applied onto the laminated film 16, and a hard coating layer (anti-glare layer) in which fine particles are dispersed in the transparent resin can be formed by irradiation with light.

On the other hand, in the case where an anti-glare layer having a fine surface uneven shape is formed by an embossing method, the shape of the mold is transferred to the first acrylic resin as long as a mold having a fine uneven shape is used. The resin layer on the layer 12 may be used. In the case where the fine surface uneven shape is formed by the embossing method, the resin layer to which the uneven shape is transferred may or may not contain inorganic or organic fine particles. The active energy ray-curable resin is suitably used for the transfer of the uneven shape by the embossing method. Particularly preferred is a UV embossing method using an ultraviolet curable resin.

In the UV embossing method, an ultraviolet curable resin layer is formed on the surface of the first acrylic resin layer 12, and the ultraviolet curable resin layer is pressed against the uneven surface of the mold to be cured, whereby the uneven surface of the mold is transferred. On the ultraviolet curable resin layer. Specifically, the ultraviolet curable resin is applied onto the first acrylic resin layer 12, and the applied ultraviolet curable resin is in close contact with the uneven surface of the mold, and ultraviolet rays are irradiated from the side of the laminated film 16 . After the ultraviolet curable resin is cured, the surface-treated laminated film 10 on which the cured ultraviolet curable resin layer is formed is peeled off from the mold, and the shape of the mold is transferred onto the ultraviolet curable resin layer. The type of the ultraviolet curable resin is not particularly limited, and various objects described above can be used. Further, instead of the ultraviolet curable resin, a photopolymerization initiator can be appropriately selected, and a visible light curable resin which can be cured by visible light longer than the ultraviolet wavelength can be used.

The thickness of the antiglare layer is not particularly limited, but is generally 2 μm or more and 30 μm or less, preferably 3 μm or more, and more preferably 20 μm or less. When the anti-glare layer is too thin, it is not When sufficient hardness is obtained, the surface tends to be easily damaged. On the other hand, when it is too thick, it becomes easy to be split, and the anti-glare layer is hardened and shrunk to cause the film to curl, resulting in a decrease in productivity. tendency.

The haze value of the antiglare layer is preferably in the range of 5% to 50%. When the haze value is too small, sufficient anti-glare performance cannot be obtained, and external light is likely to be reflected on the screen. On the other hand, when the haze value is too large, although the reflection of external light can be reduced, there is a possibility that the screen compactness indicated by 黒 is lowered.

<Pressure strength of surface-treated laminated film>

According to the present invention, the first acrylic resin layer 12 and the second acrylic acid can be formed on the single-layer first acrylic resin layer 12 of the polycarbonate-based resin layer 15 or on both surfaces of the polycarbonate-based resin layer 15. Further, the surface layer 10 of the surface treatment layer 18 is provided on the first acrylic resin layer 12, and the pressure-sensitive strength is 20 N or more. When the pressing strength is small, the surface-treated laminated film 10 is bonded to other layers, for example, a process of a polarizing film, since the surface-treated laminated film 10 is insufficient in strength to be easily broken, and there is a problem of a contamination process. Moreover, when the film is broken, it is necessary to re-clean, convey, and the like, and it takes time to re-attach, so that extra cost is incurred. The pressurization strength is more preferably 22 N or more. Here, the pressurization strength is measured by the film specified in JIS K7124-2:1999 "Plastic test method based on plastic film and sheet-free throwing method - Part 2: gauge-through method" The person who obtained the punching stress. In the metering-through method, a film having one pair of through-holes is used to fix the film horizontally, and a load cell is used to read the maximum stress when the striker penetrates at a constant speed in the vertical direction. The larger the maximum stress at this time, the meaning that the film is hard to be broken.

[Polarizer]

The surface-treated laminated film 10 described above with reference to FIGS. 1 and 2 is a cross-sectional view as shown in FIGS. 3 and 4, and the polycarbonate can be used as long as it is in the first embodiment. Resin layer The polarizing film 20 is bonded to the 15 side, and the polarizing plate 20 can be formed by bonding the second acrylic resin layer 13 side to the polarizing film 22 as long as it is the aspect shown in FIG. In this bonding, a bonding agent is generally used, and in the third and fourth figures, the bonding agent layer 23 is bonded. Any one of the polycarbonate resin layer 15 side of the surface-treated laminated film 10 or the second acrylic resin layer 13 side and the bonding surface of the polarizing film 22 may be after applying the bonding agent, and then Fit it together.

On the surface of the polarizing film 22 opposite to the surface on which the surface-treated laminated film 10 is bonded, the transparent resin film 26 which is a protective film can be attached. The transparent resin film 26 may be of the same material as the surface-treated laminated film 10 or may be a different material. Similarly, the transparent resin film 26 can be bonded to the polarizing film 22 by using a bonding agent; in the third and fourth drawings, the bonding layer 24 is still bonded to each other.

<Polarized film>

The polarizing film 22 constituting the polarizing plate 20 may be a polyvinyl alcohol-based resin which is uniaxially stretched by a step of uniaxially stretching the polyvinyl alcohol-based resin film by a well-known method. The film is dyed by a step of adsorbing the dichroic dye, a boric acid aqueous solution to treat the polyvinyl alcohol-based resin film having the dichroic dye adsorbed thereon, and a step of washing with a boric acid aqueous solution. The polarizing film obtained in this manner is an object having an absorption axis in the above-described uniaxial stretching direction.

The polyvinyl alcohol-based resin may be one obtained by saponifying with a polyvinyl acetate-based resin. The polyvinyl acetate-based resin may be, for example, a polyvinyl acetate of a single polymer of vinyl acetate, and may be, for example, a copolymer of vinyl acetate and another monomer copolymerizable therewith. Other monomers copolymerizable with vinyl acetate may be, for example, unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated decanoic acids, ammonium amides having an ammonium group, and the like.

The degree of saponification of the polyvinyl alcohol-based resin is usually from 85 mol% to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, for example, Aldehyde modified polyvinyl formaldehyde and polyvinyl acetal. Further, the degree of polymerization of the polyvinyl alcohol-based resin is usually about 1,000 to 10,000, preferably about 1,500 to 5,000.

A film obtained by forming a polyvinyl alcohol-based resin of this type can be used as an original film of a polarizing film. The method of forming a film of a polyvinyl alcohol-based resin is not particularly limited, and a well-known method can be employed. The film thickness of the polyvinyl alcohol-based original film is not particularly limited, and is, for example, about 10 μm to 150 μm.

The uniaxial stretching of the polyvinyl alcohol-based resin film may be carried out before dyeing with a dichroic dye, dyeing, or after dyeing. In the case of uniaxial stretching after dyeing, the uniaxial stretching may be performed before boric acid treatment or boric acid treatment. Further, uniaxial stretching may be performed in a plurality of stages.

The uniaxial stretching may be carried out by passing between separate cylinders having different rotation speeds, or by being held by a hot cylinder. Further, the uniaxial stretching may be dry stretching in which stretching is carried out in the air, or a solvent such as water or an organic solvent may be used, and the polyvinyl alcohol-based resin film may be stretched while being swelled. Stretching. The stretching ratio is usually about 3 times to 8 times.

The dyeing of the polyvinyl alcohol-based resin film by the dichroic dye can be carried out, for example, by immersing the polyvinyl alcohol-based resin film in an aqueous solution containing a dichroic dye. As the dichroic dye, iodine and a dichroic organic dye can be used. Further, it is preferred that the polyvinyl alcohol-based resin film is subjected to water immersion treatment before the dyeing treatment.

When iodine is used as the dichroic dye, a method in which a polyvinyl alcohol-based resin film is immersed in an aqueous solution containing iodine and potassium iodide for dyeing is usually employed. The content of iodine in the aqueous solution is usually from about 0.01 part by weight to about 1 part by weight per 100 parts by weight of water. The content of potassium iodide is usually from about 0.5 part by weight to about 20 parts by weight per 100 parts by weight of water. The temperature of the aqueous solution used for dyeing is usually about 20 ° C to 40 ° C. Further, the immersion time (dyeing time) of the aqueous solution is usually from about 20 seconds to about 1,800 seconds.

On the other hand, when a dichroic organic dye is used as the dichroic dye, a method of dyeing a polyvinyl alcohol-based resin film in an aqueous solution containing a water-soluble dichroic organic dye is usually used. . The content of the dichroic organic dye in the aqueous solution is usually from about 1 × 10 ^-4 parts by weight to about 10 parts by weight per 100 parts by weight of water; preferably from 1 × 10 ^-3 parts by weight to 1 part by weight. about. The aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing auxiliary. The temperature of the aqueous solution of the dichroic dye used for dyeing is usually about 20 ° C to 80 ° C. Further, the immersion time (dyeing time) of the aqueous solution is usually from about 10 seconds to about 1,800 seconds.

The boric acid treatment after dyeing the dichroic dye may be carried out by immersing the dyed polyvinyl alcohol-based resin film in a boric acid-containing aqueous solution. The amount of boric acid in the boric acid-containing aqueous solution is usually from 2 parts by weight to 15 parts by weight, preferably from 5 parts by weight to 12 parts by weight per 100 parts by weight of water. In the case where iodine is used as the dichroic dye, the boric acid-containing aqueous solution preferably contains potassium iodide. The amount of potassium iodide in the boric acid-containing aqueous solution is usually from 0.1 part by weight to 15 parts by weight, preferably from 5 parts by weight to 12 parts by weight per 100 parts by weight of water. The immersion time in the boric acid-containing aqueous solution is usually from about 60 seconds to about 1,200 seconds, preferably from 150 seconds to 600 seconds, and more preferably from 200 seconds to 400 seconds. The temperature of the aqueous solution containing boric acid is usually 50 ° C or higher, preferably 50 ° C to 85 ° C, and more preferably 60 ° C to 80 ° C.

The polyvinyl alcohol-based resin film after the boric acid treatment is usually subjected to a water washing treatment. The water washing treatment can be carried out, for example, by immersing a boric acid-treated polyvinyl alcohol-based resin film in water. The temperature of the water in the water washing treatment is usually about 5 ° C to 40 ° C. Further, the immersion time is usually about 1 second to 120 seconds.

After washing with water, drying treatment was carried out to obtain a polarizing film. A hot air dryer or a far infrared heater can be used for the drying treatment. The temperature of the drying treatment is usually about 30 ° C to 100 ° C, preferably 50 ° C to 80 ° C. The drying time is usually from 60 seconds to 600 seconds, preferably from 120 seconds to 600 seconds.

By the drying treatment, the moisture content of the polarizing film can be reduced to a practical level. The moisture content is usually 5% by weight to 20% by weight, preferably 8% by weight to 15% by weight. When the moisture content is lowered to 5% by weight, the polarizing film loses flexibility, and the polarizing film may be damaged or broken after the drying. On the other hand, when the moisture content exceeds 20% by weight, the thermal stability of the polarizing film tends to be insufficient.

The thickness of the polarizing film of the dichroic dye obtained by the adsorption alignment in the above manner may be usually about 5 μm to 40 μm.

<Transparent resin film adhered to the side of one side of the polarizing film>

As described above with reference to FIGS. 3 and 4, the transparent resin film 26 can be bonded to the opposite side of the surface of the polarizing film 22 to which the surface-treated laminated film 10 is bonded. The transparent resin film 26 is not particularly limited as long as it has a function as a protective film or a retardation film as a polarizing plate, and may be, for example, a cellulose triacetate film, a polycarbonate film, or a polyterephthalic acid. An ethylene glycol film, an acrylic resin film, a laminated film of an acrylic resin and a polycarbonate resin, an olefin resin film, or the like. Among these, an olefin resin film is preferably used.

The olefin-based resin is, for example, a chain olefin monomer such as ethylene or propylene or a ring-like olefin such as norbornene or other cyclopentadiene derivative, which is used as a catalyst for polymerization. A resin obtained by polymerizing an olefin monomer.

The olefin-based resin obtained from the chain olefin monomer may be, for example, a polyethylene resin or a polypropylene resin. Among these, a polypropylene which is a single polymer of propylene is preferred. Further, it is preferred that propylene is mainly used as a main component and a comonomer copolymerizable with propylene is usually used in a ratio of from 1% by weight to 20% by weight, more preferably from 3% by weight to 10% by weight. A polypropylene-based copolymerized resin obtained by polymerization.

The comonomer which can be copolymerized with propylene is preferably ethylene, 1-butene or 1-hexene. Among these, from the viewpoint of excellent transparency and stretch workability, it is preferred to use ethylene; The polypropylene-based copolymer resin obtained by copolymerizing ethylene with a ratio of 8% by weight to 20% by weight, particularly 3% by weight to 10% by weight, is desirable. When the copolymerization ratio of ethylene is set to 1% by weight or more, the effect of improving transparency and drawing processability can be found. On the other hand, when the ratio exceeds 20% by weight, the melting point of the resin is lowered to impair the heat resistance required for the protective film or the retardation film.

A commercially available product of a polypropylene-based resin can be easily obtained, for example, "Blem Polypropylene" sold under the trade name by Bloom Polymer Co., Ltd.; sold by Japan Polypropylene Co., Ltd. "Naubert" and "Ventek"; "Sumitomo Nabu South" sold by Sumitomo Chemical Co., Ltd.; "San Aroma" sold by San Aroma Co., Ltd., etc.

The olefin-based resin obtained by polymerizing a cyclic olefin monomer is also generally referred to as a cyclic olefin resin, an alicyclic olefin resin, or a norbornene resin. This is called a cyclic olefin resin.

The cyclic olefin-based resin is, for example, subjected to ring-opening disproportionation polymerization using norbornene or a derivative thereof obtained from cyclopentadiene and an olefin via a Diels-Ard reaction, and then continuing. a resin obtained by hydrogenation; a tetracyclododecene or a derivative thereof obtained from dicyclopentadiene and an olefin or a (meth) acrylate via a Diels-Alder reaction as a monomer , performing ring-opening disproportionation polymerization, and then continuing the resin obtained by hydrogenation; using two or more kinds of norbornene, tetracyclododecene, derivatives thereof, or other cyclic olefin monomers, Similarly, ring-opening disproportionation copolymerization is carried out, and then the resin obtained by hydrogenation is continued; at least one cyclic olefin selected from the above norbornene, tetracyclododecene, and derivatives thereof is A resin obtained by addition copolymerization of an aliphatic or aromatic compound having a vinyl group.

The cyclic olefin-based resin can also be easily obtained from commercially available products, for example, "TOPAS" (Teps), which is produced by Japan's Polyplastics Co., Ltd., manufactured by TOPAS ADVANCED POLYMERS GmbH, Germany; "Atong" sold by the company, "Jeno" and "Jenox" manufactured by Japan Jain Co., Ltd.; by Mitsui "Aberu" and other products sold by the company.

The above-mentioned chain olefin-based resin or cyclic olefin-based resin can be formed into a film to form a film, and the film can be bonded to one surface of the polarizing film 22 to form a transparent resin film 26. The method of film formation is not particularly limited, and it is preferred to use a melt extrusion film forming method.

The olefin-based resin film can also be easily obtained from commercially available products. For example, in the case of a polypropylene-based resin film, the "FILMAX CPP film" sold by FILMAX is sold under the trade name; "Santex" sold by the company, "East-Royce" sold by East-West Co., Ltd.; "Toyo Spinning Film" sold by Toyobo Co., Ltd.; by Toray Film Processing Co., Ltd. "Dong Lifang" sold; "Japan Poly SA" sold by Japan Poly S Co., Ltd.; "Taihe FC" sold by Ercun Chemical Co., Ltd. In the case of the cyclic olefin-based resin film, "Jeno Film" sold under the trade name of Japan Jayne Co., Ltd.; "Atong Film" sold by JSR Co., Ltd., and the like.

In the transparent resin film 26, an optical functional film may be laminated on the surface thereof, or an optical functional layer may be applied. Optical functional films and optical functional layers such as these may be, for example, an easy-bonding layer, a conductive layer, a hard coating layer, or the like.

The olefin-based resin film described above can be stretched to impart a refractive index anisotropy to the film and impart a function of the retardation film. The stretching method is not particularly limited as long as it is appropriately selected in accordance with the required refractive index anisotropy, and for example, longitudinal uniaxial stretching, transverse uniaxial stretching, or vertical and horizontal sequential biaxial stretching may be employed. .

The olefin-based resin has a positive refractive index anisotropy, and since the refractive index becomes maximum in the direction in which the stress is applied, when the film has been uniaxially stretched, the refractive index difference of n _x >n _y ≒n _z is usually supplied. Directional. Here, n _x is a refractive index in the in-plane slow axis direction of the film (the direction in which the in-plane refractive index is the largest, and the resin having a positive refractive index anisotropy is the stretching direction); n _y is a film The refractive index of the in-plane axis direction (the direction perpendicular to the slow axis in the plane); n _z is the refractive index of the film in the normal direction. When the olefin-based resin is a film which is subjected to sequential biaxial stretching, it is usually provided with refractive index anisotropy of n _x >n _y >n _z .

Further, in order to provide a desired refractive index characteristic, a phase difference may be produced by laminating a film for the purpose of a heat-shrinkable film instead of stretching, or by performing a stretching process and shrinking the film. film. Such an operation is usually performed to obtain a retardation film having a refractive index anisotropy of n _x >n _z >n _y or n _z >n _x ≧n _y .

A retardation film made of an olefin resin can also be easily obtained from a commercially available product. For example, in the case of a retardation film composed of a cyclic olefin resin, "Jeno Film" sold under the trade name of Japan Jayne Co., Ltd.; "Atong" sold by JSR Co., Ltd. "E-film"; "S-phase retardation film" sold by Sekisui Chemical Industry Co., Ltd., etc.

[Joining of polarizing film and surface-treated laminated film and transparent resin film]

In the surface treatment of the polycarbonate resin layer 15 of the laminated film 10, the bonding of the second acrylic resin layer 13 and the polarizing film 22, and the bonding of the polarizing film 22 and the transparent resin film 26, as described above, Use a bonding agent. Preferably, the bonding surface of the polycarbonate resin layer 15 constituting the surface-treated laminated film 10 or the polarizing film 22 of the second acrylic resin layer 13 and the surface treatment of the polarizing film 22 are bonded before bonding. At least one of the bonding surfaces of the laminated film 10 and at least one of the bonding surface of the transparent resin film 26 of the polarizing film 22 and the bonding surface of the polarizing film 22 of the transparent resin film 26 are previously implemented. Corona discharge treatment, plasma irradiation treatment, electron beam irradiation treatment, and other surface activation treatment.

The bonding agent for forming the bonding layers 23 and 24 as shown in FIGS. 3 and 4 can be arbitrarily selected from among those capable of exhibiting bonding force with respect to individual members. Typically, it is a water-based cement, for example, it may be a material obtained by dissolving a binder component in water or dispersing a binder component in water, and an active energy containing a component hardened by irradiation of an active energy ray. Wire hardening bonding agent, etc. From the viewpoint of productivity, it is preferred to use an active energy ray-curable cement.

First, a water-based bonding agent, for example, a preferred bonding agent, for example, A composition containing a polyvinyl alcohol-based resin or a urethane resin as a main component may be used.

When the water-based bonding agent is a polyvinyl alcohol-based resin as a main component, the polyvinyl alcohol-based resin may be modified, such as a carboxyl group, in addition to a partially saponified polyvinyl alcohol or a fully saponified polyvinyl alcohol. Modified polyvinyl alcohol-based resin such as polyvinyl alcohol, ethylene glycol modified polyvinyl alcohol, hydroxymethyl modified polyvinyl alcohol, and amine modified polyvinyl alcohol . When a polyvinyl alcohol-based resin is used as the binder component, the binder is mostly an aqueous solution prepared into a polyvinyl alcohol-based resin. The concentration of the polyvinyl alcohol-based resin in the aqueous solution of the binder is usually about 1 to 10 parts by weight, preferably 1 to 5 parts by weight, per 100 parts by weight of water.

In order to improve the bondability, the water-based adhesive containing a polyvinyl alcohol-based resin as a main component is preferably a curable component or a crosslinking agent such as glyoxal or a water-soluble epoxy resin. The water-soluble epoxy, for example, may be a reaction between a polyalkylene polyamine such as diethylenetriamine or triethylenetetramine, and a dicarboxylic acid such as adipic acid. The obtained polyamidamine polyamine is a polyamidamine polyamine epoxy resin obtained by reacting with epichlorohydrin. Commercial products of such polyamine polyamine epoxy resins, for example, "amine series resin 650" and "amine series resin 675" sold by Susei Chemical Technology Co., Ltd.; by Japan PMC Co., Ltd. The "WS-525" sold, etc., can be used as appropriate. The amount of the curable component or the crosslinking agent to be added is usually 1 to 100 parts by weight, preferably 1 to 50 parts by weight, per 100 parts by weight of the polyvinyl alcohol-based resin. When the amount of addition is small, the effect of improving the bonding property is small. On the other hand, when the amount of addition is large, the binder layer tends to become brittle.

In the case where a urethane resin is used as a main component of the aqueous binder, an example of a suitable binder composition may be, for example, a polyester-based ionic polymer urethane resin, and has a shrinkage A mixture of compounds of glyceryloxy groups. The polyester-based ionic polymer type urethane resin referred to herein means a urethane resin having a polyester skeleton, and a small amount of an ionic component (hydrophilic component) is introduced therein. The ionic polymer type urethane resin is emulsified directly into water to form an emulsion without using an emulsifier, and is therefore suitable as a water-based bonding agent. Polyester ionic polymer type The urethane resin is used for the bonding of the polarizing film and the protective film. For example, it is disclosed in JP-A-2005-70139, JP-A-2005-70140, JP-A-2005-181817, and the like. It is well known.

On the other hand, when an activated energy ray-curable bonding agent is used, a component which is cured by irradiation with an active energy ray (hereinafter sometimes referred to simply as "curable component") may be an epoxy. A base compound, an octacene compound, a propylene oxide compound, or the like. In the case of using a cationically polymerizable compound such as an epoxy compound or an octene compound, a cationic polymerization initiator may be blended. Further, in the case of using a radical polymerizable compound such as an propylene oxide compound, a radical polymerization initiator may be blended. Among these, a bonding agent in which an epoxy compound is one of hardening components is preferable, and an alicyclic epoxy compound in which an epoxy group is directly bonded to a saturated carbocyclic ring is preferable as a curing property. A bonding agent for one of the ingredients. Further, it is also effective to use it in combination with an oxetane compound.

The epoxy compound can also be easily obtained from commercially available products, for example, the "epoxy coating" series sold under the trade name by Japan Epoxy Resin Co., Ltd.; the "epoxy" sold by DIC Co., Ltd. "Clone" series; "epoxy" series sold by Dongdu Chemical Co., Ltd.; "ADEKA resin" series sold by ADEKA Co., Ltd.; "Danak" series sold by Changchun Chemical Technology Co., Ltd. "Dayu Epoxy" series sold by Daewoo Chemical Co., Ltd.; "Epoxy Repository" sold by Nissan Chemical Industry Co., Ltd.

The alicyclic epoxy compound in which an epoxy group is directly bonded to a saturated carbocyclic ring can also be easily obtained from a commercially available product, for example, "Siro" which is sold under the trade name by Daisy Chemical Industry Co., Ltd. The Saite series and the "Sekulema" series; the "Selek" series sold by Daewoo Chemical Society.

The oxetane compound can also be easily obtained from commercially available products, for example, the "Alon oxetane" series sold under the trade name by East Asia Synthetic Co., Ltd.; The "ETERNACOLL" series sold.

The cationic polymerization initiator can also be easily obtained from commercially available products, for example, the "Kayanat" series sold under the trade name by Nippon Kayaku Co., Ltd.; "Seleka" sold by Union Carbo Series; Photoacid generator "CPI" series sold by Sun Apollo Co., Ltd.; photoacid generators "TAZ", "BBI" and "DTS" sold by Midea Chemical Co., Ltd.; The "ADEKA Photopolymer" series sold by ADEKA Co., Ltd.; the "RHODORSIL" series sold by Rodias.

The active energy ray-curable bonding agent may contain a photosensitizer as needed. By using a photosensitizer, the reactivity can be improved, and the mechanical strength and bonding strength of the cured layer can be further improved. The photosensitizer may, for example, be a carbonyl compound, an organic sulfur compound, a persulfide compound, a redox compound, an azo or a diazo compound, an anthraquinone compound, a halogen compound, a photoreductive dye or the like.

Further, in the active energy ray-curable bonding agent, various additives may be blended in a range that does not impair the bonding property. The additive may be, for example, an ion trapping agent, an antioxidant, a chain shifting agent, an adhesion-imparting agent, a thermoplastic resin, a filler, a flow regulator, a plasticizer, an antifoaming agent, or the like. Further, a curable component which is hardened by another reaction mechanism different from the cationic polymerization may be blended in a range which does not impair the bonding property.

The active energy ray-curable bonding agent described above is applied to the bonding surface of the polycarbonate resin layer 15 of the surface-treated laminated film 10, the second acrylic resin layer 13, or the polarizing film 22, and is passed through the coating layer. After the two are bonded together, the portion is irradiated with an active energy ray to be cured, and the bonding layer 23 of the polarizing film 22 and the polycarbonate resin layer 15 or the second acrylic resin layer 13 is bonded. Further, the bonding surface coated on the polarizing film 22 or the transparent resin film 26 is bonded to the bonding layer through the coating layer, and then cured by irradiation with an active energy ray to form a bonding polarizing film 22. The bonding layer 24 with the transparent resin film 26. The bonding agent for forming the bonding agent layer 23 and the bonding agent for forming the bonding agent layer 24 may be the same composition or different compositions; Preferably, however, it is carried out simultaneously with the irradiation of the active energy ray for hardening the two.

The active energy ray for curing the active energy ray-curable bonding agent may be, for example, X-rays having a wavelength of 1 nm to 10 nm, ultraviolet rays having a wavelength of 10 nm to 400 nm, visible rays having a wavelength of 400 nm to 800 nm, or the like. Among these, it is preferable to use ultraviolet rays from the viewpoint of easiness of use, ease of preparation of the active energy ray-curable bonding agent, stability, and curing performance. As the light source of the ultraviolet light, for example, a low-pressure mercury lamp having a light-emitting distribution of a wavelength of 400 nm or less, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh pressure mercury lamp, a chemical lamp, a black lamp, a microwave-excited mercury lamp, a metal halide lamp, or the like can be used.

The thickness of the bonding agent layer obtained by using the active energy ray-curable bonding agent is usually about 1 μm to 50 μm, but particularly preferably in the range of 1 μm to 10 μm.

[Use of polarizing plate]

The polarizing plate 20 which is a representative example of the configuration shown in FIGS. 3 and 4 can be bonded to the identification side of the liquid crystal cell to form a liquid crystal panel which can be used for a liquid crystal display device. On the opposite side of the liquid crystal cell, another polarizing plate is usually attached. In order to adhere to the liquid crystal cell, an adhesive layer may be provided on the outer side of the transparent resin film 26, that is, on the opposite side of the bonding surface of the polarizing film 22. The pressure-sensitive adhesive layer is generally formed by using an acrylate as a main component and an acrylic resin obtained by copolymerizing an acrylate resin containing a functional group-containing acrylic monomer as an adhesive component. When the adhesive layer is bonded to the liquid crystal cell in this way, the liquid crystal panel in which the surface-treated laminated film 10 is disposed on the identification side is obtained. As the liquid crystal cell constituting the liquid crystal panel, various substances used in the field can be used.

<Example>

Hereinafter, the present invention will be more specifically described by way of examples, but the invention is not limited to the examples. In the examples, % and parts of the content and the amount used are indicated, unless otherwise specified, that is, based on the weight.

Moreover, in the examples and the comparative examples, each was measured by the following method: The internal haze and the in-plane retardation value Ro of the laminated film before the surface layer formed by extrusion are pressed, and the press strength, pencil hardness and full haze of the surface-treated laminated film.

[Measurement of Internal Haze of Laminate Film]

In the state in which the laminated film sample is immersed in a quartz unit containing dimethyl phthalate (the surface haze is actually 0), the mist is carried out in accordance with JIS K7105-1981 "Test method for optical properties of plastics". Determination of degree.

[Measurement of in-plane retardation value Ro of laminated film]

The in-plane phase difference value Ro of the laminated film at a wavelength of 590 nm was measured using a phase difference measuring device "KOBRA-WR" manufactured by Oji Scientific Instruments Co., Ltd.

[Measurement of Pressurization Strength of Surface Treatment Laminate Film]

The pressure strength of the surface-treated laminated film is "LF Plus Royd Material Testing Machine" purchased by Yasushi Seiki Co., Ltd., and is based on JIS K7124-2:1999 "Plastic Film and Sheet-Free Falling Method" The measurement method of the smashing test method - the second part: the metering penetration method is performed. At this time, the inner diameter of the test piece jig (the diameter of the circle on which the test piece was subjected to punching) was 15 mm, and a hemispherical snoring surface having a diameter of 10 mm which can be dropped by the striker was set at the center thereof. The punching test speed was set to 0.5 mm/min. Further, the surface to which the striker is in contact is on the opposite side to the surface-forming layer forming surface, that is, the acrylic resin layer in which the polycarbonate resin layer or the surface treatment layer is not formed. The maximum stress in the punch test is the pressurization strength.

[Measurement of pencil hardness of surface-treated laminated film]

The pencil hardness of the surface-treated laminated film is the surface-treated surface according to JIS K5600-5-4:1999 "General Test Methods for Coatings - Part 5. Mechanical Properties of Coating Films - Section 4: Scratch Hardness (Pencil Method) The predetermined pencil hardness test was carried out by placing the surface-treated laminated film on which the hard coating layer was formed on the surface of the surface treatment layer.

[Measurement of full haze of surface-treated laminated film]

For the surface-treated laminated film sample, the haze was measured in accordance with JIS K7136:2000 "Method for determining the haze of plastic-transparent material".

[Examples 1 to 4]

(A) Production of laminated film

The innermost layer is composed of a hard polymer obtained by polymerizing methyl methacrylate and a small amount of allyl methacrylate; the intermediate layer is composed of butyl acrylate as a main component, and styrene and a small amount are further used. a soft rubber elastomer obtained by polymerizing allyl methacrylate; the outermost layer is a three-layer composed of a hard polymer obtained by polymerizing methyl methacrylate and a small amount of ethyl acrylate. Elastomer particles of the structure; the rubber elastomer particles having an average particle diameter of 240 nm of the intermediate layer are used as the rubber elastomer particles. Further, in the rubber elastic particles, the total weight of the innermost layer and the intermediate layer was 70% of the entire particles. On the other hand, "ALTUGLAS HT121" which is a methyl methacrylate resin manufactured by Arkema Co., Ltd. is prepared according to the ratio described in the column of "Rubber amount" in Table 1. The rubber elastomer particles are blended thereon to form an acrylic resin composition. Further, the "rubber amount" in Tables 1 to 3 is the total weight of the innermost layer and the intermediate layer in the rubber elastic particles, and the ratio of the rubber resin composition to the acrylic resin composition.

Further, as the polycarbonate resin, "Kaliba 301-10" manufactured by Stallone Polycarbonate Co., Ltd. was used.

The pellets of the acrylic resin composition were placed in a 65 mm crucible uniaxial extruder, and the polycarbonate resin was placed in a 45 mm crucible uniaxial extruder and melted, thereby being multi-manifold. The molten laminate was integrated and extruded through a T-die set at a set temperature of 260 °C. The obtained film was poured between a pair of metal cylinders having a smooth surface to form a laminated film having a thickness of 80 μm. At this time, by adjusting the amount of extrusion of the extruder, the ratio of the polycarbonate resin layer to the full film thickness of the laminated film is adjusted so as to be in the "PC layer ratio" column as shown in Table 1. The ratio shown. The internal haze and surface measured for the obtained laminated film The results of the internal phase difference value Ro are shown in Table 1.

(B) Modification of coating liquid for forming a surface treatment layer

The weight ratio of the former/the latter containing the pentaerythritol triacrylate and the polyfunctional urethane acrylate (the reaction product of hexamethylene diisocyanate and pentaerythritol triacrylate) was 60 with ethyl acetate as a solvent. /40, the total concentration of the two is 60%, and a photocurable resin composition in which a leveling agent is blended is formed. The pentaerythritol triacrylate and the polyfunctional urethane-based acrylate constituting the photocurable resin composition are collectively referred to as "curable acrylate". A coating liquid for forming a surface treatment layer was prepared by adding 100 parts of a curable acrylate of a photocurable resin composition and 1 part of a photopolymerization initiator "Iru kawakua 184" manufactured by BASF.

(C) Fabrication of surface treated laminate film

The coating liquid for forming a surface treatment layer prepared in the above (B) is applied to the surface of the acrylic resin layer of the laminated film produced in the above (A) so that the thickness of the coating film after drying is 6 μm. It was kept in a dryer set at 80 ° C for 1 minute to dry the coating film. After the drying, the light emitted from the high-pressure mercury lamp having a strength of 20 mW/cm ^{2 was} irradiated from the coating film side of the film so as to be in an acrylic resin layer so that the amount of light converted into h light was 400 mJ/cm ² . A surface-treated laminated film having a surface treated layer formed on the surface. The results of measuring the press strength, the pencil hardness, and the full haze for the obtained surface-treated laminated film are shown in Table 1. Further, the surface-treated layer forming surface is outside, and the film is not broken even if it is bent and folded, and the folding resistance is good.

[Example 5]

(A) Production of laminated film

A laminate film having a thickness of 80 μm was produced on the basis of (A) of Examples 1 to 4, except that a three-layer structure of the first acrylic resin layer/polycarbonate resin layer/second acrylic resin layer was formed. In this case, the ratio of the blending amount of the rubber elastic particles in the acrylic resin and the ratio of the polycarbonate resin layer in the total film thickness of the laminated film is set to the "rubber amount" in Table 1 respectively. And "PC layer ratio" The composition and thickness of the first and second acrylic resin layers are the same as shown in the respective columns. The results of measuring the internal haze and the in-plane retardation value Ro of the laminated film obtained here are shown in Table 1.

(C) Fabrication of surface treated laminate film

On the surface of one of the acrylic resin layers of the laminated film produced in the above (A), a surface-treated layer was formed in the same manner as in (C) of Examples 1 to 4 to prepare a surface-treated laminated film. The results of measuring the press strength, the pencil hardness, and the full haze of the obtained surface-treated laminated film are shown in Table 1. Also, the folding endurance is good.

[Comparative Examples 1 to 3]

(A) Production of laminated film

In the same manner as in (A) of Examples 1 to 4, thickness was produced in addition to pellets of the same acrylic resin in both a 65 mm uniaxial extruder and a 45 mm uniaxial extruder. It is a single layer film of an 80 μm acrylic resin. At this time, the blending amount of the rubber elastomer particles in the acrylic resin is as shown in the column of "Rubber amount" in Table 1. The results of measuring the internal haze and the in-plane retardation value Ro of the film obtained here are shown in Table 1.

(C) Fabrication of surface treated film

On the surface of one of the single-layer films produced in the above (A), a surface-treated layer was formed in the same manner as in (C) of Examples 1 to 4 to prepare a surface-treated film. The results of measuring the press strength, the pencil hardness, and the full haze of the obtained surface treated film are shown in Table 1. Since the polycarbonate-based resin layer is not provided, the surface-treated layer is formed on the outer side, and when the film is bent and folded, cracking occurs, and the folding resistance is not good.

[Comparative Examples 4 to 6]

The ratio of the blending amount of the rubber elastic particles in the acrylic resin and the ratio of the polycarbonate resin layer of the full film thickness of the laminated film to the "rubber amount" and "PC" in Table 1 are respectively set. In the columns shown in the respective columns, the other layers are formed as laminated films and surfaces based on Examples 1 to 4. Stratified film. The physical property measurement results of the obtained films are shown in Table 1. Although the surface-treated laminated film of these was obtained with good folding resistance by the application of the polycarbonate-based resin layer, the film of Comparative Example 4 had too much content of the rubber-elastomer particles in the acrylic resin, and Comparative Example The film of 5 and 6 has a too large proportion of the polycarbonate resin layer with respect to the full film thickness of the laminated film, so that none of them can exhibit the desired pencil hardness.

[Comparative Example 7]

The ratio of the blending amount of the rubber elastomer particles in the acrylic resin and the ratio of the polycarbonate resin layer in the total film thickness of the laminated film is set to "rubber amount" and " The three layers of the laminated film and the surface-treated laminated film which are produced in the same manner as in the fifth embodiment are shown in the respective columns of the "PC layer ratio". The measurement results of the physical properties of each of the obtained films are shown in Table 1. Although the surface-treated laminated film was excellent in folding resistance, the thickness (25 μm) of the acrylic resin layer on which the surface-treated layer was formed was too thin to exhibit a desired pencil hardness.

[Examples 6 to 7]

(A) Production of laminated film

In addition to setting the amount of rubber elastomer particles to the "rubber amount" of "PMMA-1 layer" as shown in Table 2 In addition to the amounts described in the column, the first acrylic resin composition was adjusted based on (A) of Examples 1 to 4; the amount of the rubber elastomer particles was set to "PMMA-2 layer" of Table 2 In addition to the amounts described in the column, the second acrylic resin composition was adjusted based on (A) of Examples 1 to 4.

Then, the pellets of the first acrylic resin composition were respectively placed in a 65 mm crucible uniaxial extruder, and the same polycarbonate resin as those of the first to fourth embodiments was put into a uniaxial extrusion of 45 mm ψ. In the press, the pellet of the second acrylic resin composition was placed in a 40 mm crucible uniaxial extruder, melted and melted in a multi-manifold manner, and passed through a T-die which was set to a temperature of 260 ° C. Press out. The obtained film material was molded between a pair of metal cylinders having a smooth surface to form a first acrylic resin layer/polycarbonate resin layer/second acrylic acid having a thickness of 60 μm. A laminated film composed of three layers of a resin layer. At this time, by adjusting the amount of extrusion of the extruder, the ratio of the polycarbonate resin layer to the full film thickness of the laminated film is adjusted as shown in the "PC layer ratio" column of Table 2. . The results of measuring the internal haze and the in-plane retardation value Ro of the obtained laminated film are shown in Table 2.

(C) Fabrication of surface treated laminate film

On the surface of the first acrylic resin layer of the laminated film produced in the above (A), a surface-treated layer was formed in the same manner as in (C) of Examples 1 to 4 to prepare a surface-treated laminated film. The results of measuring the press strength, the pencil hardness, and the full haze of the obtained surface-treated laminated film are shown in Table 2. Also, the folding endurance is good.

PMMA-1 layer: first acrylic resin layer

PC layer: polycarbonate resin layer

PMMA-2 layer: second acrylic resin layer

[Examples 8 to 9]

The ratio of the blending amount of the rubber elastomer particles in the acrylic resin and the ratio of the polycarbonate resin layer of the full film thickness of the laminated film to the "rubber amount" and "PC" in Table 3, respectively. As shown in each column of the layer ratio, the thickness of the laminated film was set to 60 μm, and other layers were produced as a laminated film and a surface-treated laminated film based on Examples 1 to 4. The physical property measurement results of the obtained films are shown in Table 3.

[Comparative Example 8]

A single layer film and a surface treated film were produced on the basis of Comparative Example 1 except that the thickness was changed to 60 μm. The physical property measurement results of the obtained films are shown in Table 3. Since the polycarbonate-based resin layer is not provided, the obtained surface-treated film has poor folding resistance.

"The possibility of industrial use"

The single-layer film of the surface-treated acrylic resin is easily brittle and easily broken. However, the surface-treated laminated film of the present invention in which the polycarbonate-based resin layer is laminated is difficult to be broken. Therefore, it is possible to improve adhesion to other layers, for example, production stability when laminated with a polarizing film, and it is industrially advantageous to manufacture a functional film which is additionally laminated with other layers, for example, a polarizing plate.

10‧‧‧Surface treatment laminated film

12‧‧‧First acrylic resin layer

15‧‧‧Polycarbonate resin layer

16‧‧‧Laminated film

18‧‧‧Surface treatment layer

Claims (8)

A surface-treated laminated film comprising a polycarbonate-based resin layer, an acrylic resin layer, and a surface-treated layered surface-treated laminated film; wherein the acrylic resin layer is laminated on one side of the polycarbonate-based resin layer or In the case where the acrylic resin layer is laminated on one surface of the polycarbonate resin layer, the surface treatment layer is formed on the opposite side of the acrylic resin layer and the polycarbonate resin layer. In the case where the acrylic resin layer is laminated on both surfaces of the polycarbonate resin layer, the surface treatment layer is formed on one side of the acrylic resin layer and the polycarbonate system. The surface of the resin layer is opposite to the surface of the resin layer; the surface treatment layer has a pencil hardness of H or harder than H; and the polycarbonate resin layer and the acrylic resin layer on one or both sides of the layer are 35 μm. a film thickness of -100 μm and an internal haze of 5% or less; the thickness of the polycarbonate resin layer is such that the polycarbonate resin layer and the layer are one side of the layer The total thickness of the acrylic resin layers on both sides is 2% to less than 30%, and the thickness of the acrylic resin layer on which the surface treatment layer is formed is 30 μm or more. The surface-treated laminated film according to claim 1, wherein the acrylic resin layer is rubber elastic having an average particle diameter of 10 nm to 350 nm in a proportion of 30% by weight or less based on the total amount of the total. The acrylic resin composition of the bulk particles is formed. The surface-treated laminated film according to claim 1 or 2, which has a pressurizing strength of 20 N or more. The surface-treated laminated film according to the first or second aspect of the invention is used as a protective film of a polarizing film comprising a polyvinyl alcohol-based resin which is adsorbed and has a dichroic dye. The surface-treated laminated film according to claim 4, wherein the aforementioned polycarbonate resin The layer and the acrylic resin layer on one or both sides of the layered layer have a total in-plane retardation value of 100 nm or less. A polarizing plate comprising: a surface-treated laminated film according to claim 4 or 5; a polarizing film composed of a polyvinyl alcohol-based resin adsorbed and assigned with a dichroic dye; And a protective film made of a transparent resin; wherein the polarizing film is disposed opposite to a surface of the surface-treated laminated film opposite to the surface-treated layer. The polarizing plate according to claim 6, wherein the surface-treated laminated film and the protective film are respectively adhered to the polarizing film through a cured layer of an active energy ray-curable bonding agent. The polarizing plate of claim 6 or 7, wherein the protective film has a function of a retardation film.