JP5305129B2 - LAMINATED FILM MANUFACTURING METHOD AND LAMINATED FILM - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a laminated film which is formed from: a base film having an alicyclic structure-containing polymer film layer or a (meth)acrylic based resin film layer on the uppermost surface of at least one side of the base film; and an urethane resin layer and which, when laminated onto another optical film, in particular, a polarizer and used, has satisfactory adhesiveness with the laminated other film while maintaining characteristics as an optical material even when the laminated film has a heat history exposed under a high temperature and, and to provide the laminated film manufactured by the method. <P>SOLUTION: The method of manufacturing laminated film includes a process of applying a water dispersion material including an aqueous urethane resin prepared by neutralizing at least a part of acid structure contained in an acid structure-containing aqueous urethane resin with a nonvolatile base onto the surface of the film layer of the base film which has the alicyclic structure-containing polymer film layer or the (meth)acrylic based resin film layer on the uppermost surface of at least one side of the base film. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a laminated film and a laminated film produced by this method. More specifically, the present invention can be used for various image display devices such as a liquid crystal display device, an organic EL display device and a plasma display, and as an optical material. It is related with the manufacturing method of a laminated film with favorable adhesiveness with another optical film, especially a polarizer, and the laminated film manufactured by this method, maintaining the characteristic of this.

  As films used in various image display devices such as liquid crystal display devices, organic EL display devices, and plasma displays, films containing alicyclic structure-containing polymers such as norbornene polymers or (meth) acrylic resins are known. ing. Since these films are excellent in heat resistance, transparency and optical properties, for example, an electrode substrate of a liquid crystal cell constituting a liquid crystal display element, a polarizing plate, a protective film for polarizing plate, a retardation film, a viewing angle widening film Development of optical films such as brightness enhancement films and films with transparent electrodes for touch panels, optical applications such as light guide plates and optical disks is being attempted. These films are often used by being laminated on a film or substrate having various other functions such as a polarizing film, a hard coat layer, an antireflection layer, an antistatic layer, an antiglare layer, and an antifouling layer. Therefore, it is preferable that the adhesiveness with the laminated | stacked film or board | substrate is favorable. Until now, various attempts have been made to improve the adhesion between an alicyclic structure-containing polymer film or a film containing a (meth) acrylic resin and a film or substrate containing another resin on which the film is laminated. ing.

  For example, claim 1 of Patent Document 1 describes “a polarizing plate protective film characterized in that a polyurethane resin layer is formed on a thermoplastic saturated norbornene-based resin film”.

  Further, claim 1 of Patent Document 2 describes “a polarizing plate characterized in that a norbornene-based resin film, a polyurethane layer, an adhesive layer, and a polarizing film are laminated”.

Japanese Patent Laid-Open No. 2001-174637 JP 2006-201736 A

  An object of the present invention is that a laminated film formed of a base film and a urethane resin layer having an alicyclic structure-containing polymer film layer or a (meth) acrylic resin film layer on at least one outer surface thereof has a high temperature. Even if it has a thermal history exposed underneath, while maintaining the properties as an optical material, when it is used by being laminated to other optical films, particularly polarizers, the adhesion with the laminated film is It is to provide a method for producing a laminated film that is good and a laminated film produced by this method.

As means for solving the problems,
Claim 1 is an acid structure-containing aqueous urethane resin on the surface of the film layer of a base film having an alicyclic structure-containing polymer film layer or a (meth) acrylic resin film layer on at least one outermost surface thereof. An aqueous dispersion containing an aqueous urethane resin obtained by neutralizing at least a part of the acid structure contained in the organic base with a non-volatile base that is an organic base having a boiling point of 100 ° C. or higher is applied to a thickness of 0.03 to 0.2 μm. A method for producing a laminated film comprising a step of forming a urethane resin layer of
Claim 2 is a method for producing a laminated film according to claim 1, wherein 20% or more of the acid structure in the acid structure-containing aqueous urethane resin is neutralized by a nonvolatile base,
Claim 3 is the method for producing a laminated film according to claim 1 or 2 , wherein the acid structure-containing water-based urethane resin is a self-emulsifying water-based urethane resin .
Claim 4 is the method for producing a laminated film according to any one of claims 1 to 3 , wherein the aqueous dispersion contains a crosslinking agent .
Claim 5 is a laminated film produced by the method for producing a laminated film according to any one of claims 1 to 4 .

  According to the method for producing a laminated film of the present invention, it is formed by a base film having a cycloaliphatic structure-containing polymer film layer or a (meth) acrylic resin film layer on at least one outer surface thereof and a urethane resin layer. Even when the laminated film has a thermal history exposed to a high temperature, the laminated film is used when laminated on another optical film, particularly a polarizer, while maintaining the properties as an optical material. It is possible to provide a laminated film having good adhesion to the film. Therefore, the laminated film manufactured by the manufacturing method of the present invention can be suitably used for an optical apparatus such as a liquid crystal display device.

The method for producing the laminated film of the present invention comprises:
An alicyclic structure-containing polymer film layer containing an alicyclic structure-containing polymer, or a (meth) acrylic resin film layer containing a (meth) acrylic resin (in the following, including both the film layer (A) and On the surface of the film layer (A) of the base film having at least one outermost surface thereof,
Water dispersion containing an aqueous urethane resin obtained by neutralizing at least a part of the acid structure contained in the acid structure-containing aqueous urethane resin with a non-volatile base (hereinafter sometimes referred to as an aqueous urethane resin after neutralization treatment). It includes a step of applying the body.

  The base film may be formed only by the alicyclic structure-containing polymer film layer or the (meth) acrylic resin film layer, or may be formed by laminating a plurality of films. When the base film is formed of a plurality of films, the film layer (A) may be provided on at least one side of the film layer (B) formed by laminating at least one film. It may be formed by providing a film layer (A) on both sides of (B). The urethane resin layer is provided on the surface on which the film layer (A) is formed.

  The film layer (B) may be a kind of film, or two or more kinds of films may be laminated. When this film layer (B) is formed by laminating a plurality of films, a film having various functions is appropriately selected as the film forming each layer according to the performance required for the laminated film of the present invention. The material of the film layer (B) is not particularly limited. For example, an alicyclic structure-containing polymer having different resin properties from the film layer (A), a chain olefin polymer such as polyethylene or polypropylene, Examples include acetylcellulose, polyvinyl alcohol, polyimide, polyarylate, polyester, polycarbonate, polysulfone, polyethersulfone, amorphous polyolefin, acrylic polymer, and epoxy resin.

  The film layer (A) contains an alicyclic structure-containing polymer or a (meth) acrylic resin.

  The alicyclic structure-containing polymer has an alicyclic structure in the repeating unit of the polymer, a polymer having an alicyclic structure in the main chain and a polymer having an alicyclic structure in the side chain. Any of these can be used. Examples of the alicyclic structure include a saturated alicyclic hydrocarbon (cycloalkane) structure and an unsaturated alicyclic hydrocarbon (cycloalkene) structure. From the viewpoint of mechanical strength, heat resistance, etc., the cycloalkane structure. Or a cycloalkene structure is preferable, and a cycloalkane structure is most preferable. The number of carbon atoms constituting the alicyclic structure is not particularly limited, but is usually 4 to 30, preferably 5 to 20, more preferably 5 to 15 in the mechanical strength, The heat resistance and the moldability of the film are highly balanced and suitable. The ratio of the repeating unit having an alicyclic structure in the alicyclic structure-containing polymer used in the present invention may be appropriately selected according to the purpose of use, preferably 55% by weight or more, Preferably it is 70 weight% or more, Most preferably, it is 90 weight% or more. When the ratio of the repeating unit having an alicyclic structure in the alicyclic structure-containing polymer is within this range, it is preferable from the viewpoint of the transparency and heat resistance of the alicyclic structure-containing polymer film layer.

  Examples of the alicyclic structure-containing polymer include norbornene resins, monocyclic olefin resins, cyclic conjugated diene resins, vinyl alicyclic hydrocarbon resins, and hydrides thereof. it can. Among these, norbornene-based resins can be suitably used because of their good transparency and moldability.

  Examples of the norbornene-based resin include a ring-opening polymer of a monomer having a norbornene structure, a ring-opening copolymer of a monomer having a norbornene structure and another monomer, a hydride thereof, and a norbornene structure. An addition polymer of a monomer having a monomer, an addition copolymer of a monomer having a norbornene structure and another monomer, or a hydride thereof. Among these, a ring-opening (co) polymer hydride of a monomer having a norbornene structure is particularly suitable from the viewpoints of transparency, moldability, heat resistance, low hygroscopicity, dimensional stability, lightness, and the like. Can be used.

Examples of the monomer having a norbornene structure include bicyclo [2.2.1] hept-2-ene (common name: norbornene), tricyclo [4.3.0.1 ^2,5 ] deca-3,7. -Diene (common name: dicyclopentadiene), 7,8-benzotricyclo [4.3.0.1 ^2,5 ] dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo [4.4. 0.1 ^2,5 . ^{17, 10} ] dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds (for example, those having a substituent in the ring). Here, examples of the substituent include an alkyl group, an alkylene group, and a polar group. Moreover, these substituents may be the same or different and a plurality may be bonded to the ring. Monomers having a norbornene structure can be used singly or in combination of two or more.

  Examples of the polar group include a hetero atom or an atomic group having a hetero atom. Examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfone group.

  Other monomers capable of ring-opening copolymerization with monomers having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene and derivatives thereof; cyclic conjugated dienes such as cyclohexadiene and cycloheptadiene; Derivatives thereof; and the like.

  A ring-opening polymer of a monomer having a norbornene structure and a ring-opening copolymer of a monomer having a norbornene structure and another monomer copolymerizable with the monomer have a known ring-opening polymerization catalyst. It can be obtained by (co) polymerization in the presence.

  Examples of other monomers that can be addition copolymerized with a monomer having a norbornene structure include α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, and 1-butene, and derivatives thereof; cyclobutene, cyclopentene, And cycloolefins such as cyclohexene and derivatives thereof; non-conjugated dienes such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, and the like. These monomers can be used alone or in combination of two or more. Among these, α-olefin is preferable and ethylene is more preferable.

  An addition polymer of a monomer having a norbornene structure and an addition copolymer of a monomer having a norbornene structure with another monomer copolymerizable with a monomer having a norbornene structure are prepared in the presence of a known addition polymerization catalyst. It can be obtained by polymerization.

Among norbornene-based resins, as repeating units, X: bicyclo [3.3.0] octane-2,4-diyl-ethylene structure and Y: tricyclo [4.3.0.1 ^2,5 ] decane-7 , 9-diyl-ethylene structure, the content of these repeating units is 90% by weight or more based on the entire repeating units of the norbornene-based resin, and the content ratio of X and the content ratio of Y Is preferably 100: 0 to 40:60 by weight ratio of X: Y. By using such a resin, it is possible to obtain an optical film that has no dimensional change in the long term and is excellent in stability of optical characteristics.

  Examples of the monocyclic olefin resin include addition polymers of cyclic olefin monomers having a single ring such as cyclohexene, cycloheptene, and cyclooctene.

  As the cyclic conjugated diene polymer, a polymer obtained by cyclization reaction of an addition polymer of a conjugated diene monomer such as 1,3-butadiene, isoprene, chloroprene or chloroprene; cyclic conjugated such as cyclopentadiene or cyclohexadiene Mention may be made of 1,2- or 1,4-addition polymers of diene monomers; and their hydrides.

  Examples of vinyl alicyclic hydrocarbon polymers include polymers of vinyl alicyclic hydrocarbon monomers such as vinylcyclohexene and vinylcyclohexane and their hydrides; vinyl aromatic hydrocarbon monomers such as styrene and α-methylstyrene. Hydrogenated product obtained by hydrogenating the aromatic ring part contained in the polymer obtained by polymerization; copolymerization of vinyl alicyclic hydrocarbon monomers or vinyl aromatic hydrocarbon monomers with these vinyl aromatic hydrocarbon monomers Examples include a hydride of an aromatic ring of a copolymer such as a random copolymer with other possible monomers or a block copolymer. Examples of the block copolymer include diblock, triblock or higher multiblock, and gradient block copolymer.

  The hydrogenation method in the case of using a hydride as the alicyclic structure-containing polymer used in the present invention is not particularly limited and can be performed according to a known method. In order to obtain a hydride, a known hydrogenation catalyst containing a transition metal such as nickel or palladium is added to the polymer solution, and hydrogen is usually added to the reaction system at −10 to + 250 ° C., preferably 0 to 200 ° C. , 0.01 to 10 MPa, preferably 0.05 to 8 MPa, and allowed to react for 0.1 to 50 hours. The hydrogenation rate is usually 50% or more, preferably 70% or more, more preferably 90% or more. The higher the hydrogenation rate, the better the fluidity and heat resistance of the polymer.

  The molecular weight of the alicyclic structure-containing polymer used in the present invention is appropriately selected according to the purpose of use, but gel permeation chromatography using cyclohexane as a solvent or toluene when the polymer resin does not dissolve. The polyisoprene or polystyrene-equivalent weight average molecular weight (Mw) measured in (1) is usually 10,000 to 100,000, preferably 15,000 to 80,000, more preferably 20,000 to 50,000. When the weight average molecular weight is in such a range, the mechanical strength and molding processability of the laminated film are highly balanced and suitable.

  The glass transition temperature of the alicyclic structure-containing polymer may be appropriately selected according to the purpose of use, but is preferably in the range of 130 to 150 ° C, more preferably 135 to 145 ° C. When the glass transition temperature is lower than 130 ° C., the durability at high temperatures is deteriorated. When the glass transition temperature is higher than 150 ° C., the durability is improved, but normal stretching is difficult.

  The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the alicyclic structure-containing polymer is 1.2 to 3.5, preferably 1.5 to 3.0, more preferably 1.8. ~ 2.7. When this value exceeds 3.5, the low-molecular component increases, so the component with a short relaxation time increases, and even if it is an alicyclic structure-containing polymer film layer having the same in-plane retardation Re at the time of high-temperature exposure, It is estimated that relaxation will increase in a short time, and the stability of the alicyclic structure-containing polymer film layer may be reduced. On the other hand, those having a molecular weight distribution lower than 1.2 lead to a decrease in resin productivity and an increase in cost, which is not practical as a display member.

The alicyclic structure-containing polymer used in the present invention preferably has an absolute value of photoelastic coefficient of 10 × 10 ⁻¹² Pa ⁻¹ or less, more preferably 7 × 10 ⁻¹² Pa ⁻¹ or less. 4 × 10 ⁻¹² Pa ⁻¹ or less is particularly preferable. The photoelastic coefficient C is expressed as follows: birefringence is Δn and stress is σ.
C = Δn / σ
It is a value represented by If the photoelastic coefficient of the alicyclic structure-containing polymer exceeds 10 × 10 ⁻¹² Pa ⁻¹ , the variation in the in-plane letter Re of the alicyclic structure-containing polymer film layer may increase.

  The alicyclic structure-containing polymer used in the present invention preferably contains substantially no particles. Here, “substantially free of particles” means that even if particles are added to the alicyclic structure-containing polymer film layer, the increase in haze from the non-added state is in the range of 0.05% or less. Means that it is acceptable. In particular, since the alicyclic structure-containing polymer lacks affinity with many organic particles and inorganic particles, when the alicyclic structure-containing polymer film layer to which the amount of particles exceeding the above range is added is stretched, Voids are easily generated, and as a result, the haze may be significantly reduced.

  The saturated water absorption of the alicyclic structure-containing polymer of the present invention is preferably 0.03% by weight or less, more preferably 0.02% by weight or less, and particularly preferably 0.01% by weight or less. When the saturated water absorption is in the above range, the time-dependent change in Re and Rth of the alicyclic structure-containing polymer film layer in the present invention can be reduced, and further, the polarized light provided with the alicyclic structure-containing polymer film layer Deterioration of the plate and the liquid crystal display device can be suppressed, and the display on the display can be kept stable and good in the long term. The saturated water absorption is a value expressed as a percentage of the mass of the test piece before immersion after the test piece is immersed in water at a constant temperature for a fixed time. Usually, it is measured by immersing in 23 ° C. water for 24 hours. The saturated water absorption rate in the alicyclic structure-containing polymer of the present invention can be adjusted to the above value, for example, by reducing the amount of polar groups in the alicyclic structure-containing polymer. A resin having no group is desired.

  The alicyclic structure-containing polymer used in the present invention includes coloring agents such as pigments and dyes, fluorescent brighteners, dispersants, thermal stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, antioxidants, You may add well-known additives, such as a lubricant, in the range which does not impair the effect of invention.

  The alicyclic structure-containing polymer film layer is not particularly limited by the production method. The alicyclic structure-containing polymer film layer can be obtained by molding the aforementioned resin or the like by a known film forming method. Examples of the film forming method include a cast forming method, an extrusion forming method, and an inflation forming method. Among these, the melt extrusion method that does not use a solvent can reduce the amount of residual volatile components efficiently, and is preferable from the viewpoints of the global environment and work environment, and excellent manufacturing efficiency. Examples of the melt extrusion method include an inflation method using a die, but a method using a T die is preferable in terms of excellent productivity and thickness accuracy.

  When the base film is formed of a plurality of films of the alicyclic structure-containing polymer film layer and the film layer (B), the base film is the produced alicyclic structure-containing polymer film layer. And the produced film layer (B) may be bonded together using an adhesive, or may be manufactured by a coextrusion method or the like without using an adhesive.

  In the case of bonding using an adhesive, the adhesive may be appropriately selected depending on the type of resin forming the alicyclic structure-containing polymer film layer and the film layer (B). For example, an acrylic adhesive, Urethane adhesive, polyester adhesive, polyvinyl alcohol adhesive, polyolefin adhesive, modified polyolefin adhesive, polyvinyl alkyl ether adhesive, rubber adhesive, ethylene-vinyl acetate adhesive, vinyl chloride Ethylene adhesives such as vinyl acetate adhesive, SEBS (styrene-ethylene-butylene-styrene copolymer) adhesive, SIS (styrene-isoprene-styrene block copolymer) adhesive, ethylene-styrene copolymer Agent, ethylene- (meth) acrylate methyl copolymer, ethylene- (meth) ethyl acrylate copolymer Acrylic acid ester-based adhesives such as coalescence and the like.

  0.1-10 micrometers is preferable and, as for the average thickness of the contact bonding layer formed with the said adhesive agent, it is more preferable that it is 0.5-5 micrometers.

  When producing a base film without using an adhesive, preferably, a coextrusion T-die method, a coextrusion inflation method, a coextrusion lamination method or the like; a film lamination molding method such as dry lamination, And well-known methods, such as a coating molding method of coating the resin solution which comprises an alicyclic structure containing polymer film layer on the surface of a film layer (B), may be utilized suitably. Among these, the coextrusion molding method is preferable from the viewpoint of manufacturing efficiency and not leaving a volatile component such as a solvent in the base film.

  Among the coextrusion molding methods, the coextrusion T-die method is preferable. Further, examples of the coextrusion T-die method include a feed block method and a multi-manifold method, but the multi-manifold method is more preferable in that variation in thickness of each film layer can be reduced.

  The alicyclic structure-containing polymer film layer used in the present invention may be a stretched film (hereinafter, sometimes referred to as a stretched film layer (A)) by stretching a non-stretched unstretched film. .

  The stretching method of the alicyclic structure-containing polymer film layer for obtaining the stretched film layer (A) used in the present invention is not particularly limited, and is stretched by either a uniaxial stretching method or a biaxial stretching method. Also good. Stretching methods include a method of uniaxial stretching in the longitudinal direction using the difference in peripheral speed on the roll side; a uniaxial stretching method such as a method of uniaxial stretching in the transverse direction using a tenter stretching machine; At the same time as stretching in the longitudinal direction using the guide rail, the biaxial stretching method that stretches in the transverse direction depending on the spread angle of the guide rail, and the longitudinal direction using the difference in the peripheral speed between the rolls, and both ends thereof A biaxial stretching method such as a sequential biaxial stretching method in which a clip is gripped and stretched in the transverse direction using a tenter stretching machine; a feed force, a pulling force, or a pulling force at different speeds can be applied in the lateral or longitudinal direction. And a method of continuously and obliquely stretching in the direction of an arbitrary angle θ with respect to the width direction of the film using a tenter stretching machine.

  Examples of the apparatus used for stretching include a longitudinal uniaxial stretching machine, a tenter stretching machine, a bubble stretching machine, and a roller stretching machine.

  The temperature during stretching is preferably between (Tg−30 ° C.) and (Tg + 60 ° C.), where Tg is the glass transition temperature of the material constituting the unstretched alicyclic structure-containing polymer film layer. Preferably, it is selected from the temperature between (Tg-10 ° C) and (Tg + 50 ° C).

  The draw ratio may be appropriately selected according to the optical properties of the stretched film layer (A) to be used, and is 1.05 to 10.0, preferably 1.1 to 2.0.

  Examples of (meth) acrylic resins include thermoplastic resins and ultraviolet curable resins.

  When the (meth) acrylic resin is a thermoplastic resin, a polymer resin having a (meth) acrylic acid ester unit as a main component is preferably used as the thermoplastic resin. This polymer resin may be a homopolymer or copolymer consisting only of (meth) acrylic acid ester, and is a copolymer of (meth) acrylic acid ester and a monomer copolymerizable therewith. May be. In addition, (meth) acrylic acid means acrylic acid or methacrylic acid. Similarly, (meth) acrylic acid ester means acrylic acid ester or methacrylic acid ester.

  The (meth) acrylic acid ester constituting the main component of the (meth) acrylic resin preferably has a structure derived from (meth) acrylic acid, an alkanol having 1 to 15 carbon atoms and a cycloalkanol. More preferably, it is a structure derived from an alkanol having 1 to 8 carbon atoms. When there are too many carbon numbers, the elongation at the time of the fracture | rupture of the brittle film obtained will become large too much.

  Specific examples of the (meth) acrylic acid ester include methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, sec-butyl acrylate. , T-butyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, n-dodecyl acrylate; methyl methacrylate, ethyl methacrylate, methacryl N-propyl acid, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, methacrylic acid 2 -Ethylhexyl, methacrylic acid n- Sill, and the like methacrylic acid n- dodecyl.

  Moreover, these (meth) acrylic acid esters may have an arbitrary substituent such as a hydroxyl group or a halogen atom. Examples of the (meth) acrylic acid ester having such a substituent include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-methacrylic acid 2- Examples include hydroxypropyl, 4-hydroxybutyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, glycidyl methacrylate, and the like. These (meth) acrylic acid esters may be used alone or in combination of two or more.

  The (meth) acrylic resin used in the present invention has a (meth) acrylic acid ester unit content of preferably 50% by weight or more, more preferably 85% by weight or more, and particularly preferably 90% by weight or more. is there.

  The monomer copolymerizable with the (meth) acrylic acid ester is not particularly limited, but α, β-ethylenically unsaturated carboxylic acid ester monomers other than the (meth) acrylic acid ester described above, α, β-ethylenically unsaturated carboxylic acid monomer, alkenyl aromatic monomer, conjugated diene monomer, non-conjugated diene monomer, vinyl cyanide monomer, unsaturated carboxylic acid amide monomer, Examples thereof include carboxylic acid unsaturated alcohol esters and olefin monomers.

  Specific examples of the α, β-ethylenically unsaturated carboxylic acid ester monomer other than the (meth) acrylic acid ester described above include dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl maleate, dimethyl itaconate, etc. Can be mentioned.

  The α, β-ethylenically unsaturated carboxylic acid monomer may be any of monocarboxylic acid, polyvalent carboxylic acid, partial ester of polyvalent carboxylic acid, and polyvalent carboxylic acid anhydride. Examples include acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, monoethyl maleate, mono n-butyl fumarate, maleic anhydride, itaconic anhydride and the like.

  Specific examples of the alkenyl aromatic monomer include styrene, α-methylstyrene, methyl α-methylstyrene, vinyl toluene and divinylbenzene.

  Specific examples of the conjugated diene monomer include 1,3-butadiene, 2-methyl-1,3-butadiene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and 2-chloro-1. , 3-butadiene, cyclopentadiene and the like. Specific examples of the non-conjugated diene monomer include 1,4-hexadiene, dicyclopentadiene, and ethylidene norbornene.

  Specific examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethylacrylonitrile and the like.

  Specific examples of the α, β-ethylenically unsaturated carboxylic acid amide monomer include acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N, N-dimethylacrylamide and the like. Specific examples of the carboxylic acid unsaturated alcohol ester monomer include vinyl acetate. Specific examples of the olefin monomer include ethylene, propylene, butene, pentene and the like.

  As the monomer copolymerizable with (meth) acrylic acid ester, one type may be used alone, or two or more types may be used in combination. As a monomer copolymerizable with (meth) acrylic acid ester, an alkenyl aromatic monomer is preferable, and styrene is particularly preferable.

  In the (meth) acrylic resin used in the present invention, the content of the monomer unit of the monomer copolymerizable with the (meth) acrylic acid ester is preferably 50% by weight or less, more preferably 15% by weight. Hereinafter, it is particularly preferably 10% by weight or less.

  Preferable specific examples of the (meth) acrylic resin used in the present invention include methyl methacrylate / methyl acrylate / butyl acrylate / styrene copolymer, methyl methacrylate / methyl acrylate copolymer, methyl methacrylate / Examples thereof include styrene / butyl acrylate copolymers. One (meth) acrylic resin may be used alone, or two or more may be used in combination. In the present invention, among these, a polymethacrylate resin is preferable, and among them, a polymethyl methacrylate resin is more preferable.

  Although the molecular weight of (meth) acrylic-type resin is not specifically limited, Usually, it is 50,000-500,000 in a weight average molecular weight. When the molecular weight is within this range, a homogeneous (meth) acrylic resin film layer can be easily produced by the melt casting method.

  The (meth) acrylic resin used in the present invention preferably has an elongation at break in the tensile test in the range of 10 to 180%, and more preferably in the range of 50 to 170%. When the elongation at break is within the above range, the bristle film has good dregs. When two or more kinds of (meth) acrylic resins are used in combination, the elongation at break of the mixture is preferably within the above range. The elongation at break is a value obtained under the conditions of test piece type 1B (W10, L100, t0.1 mm) and speed of 5 mm / min according to JIS K 7127.

  The thermoplastic (meth) acrylic resin film layer is not particularly limited by the production method. The thermoplastic acrylic resin film layer is obtained by molding by the same film molding method as the above-described alicyclic structure-containing polymer film layer. When the base film is formed of a plurality of (meth) acrylic resin film layers and film layers (B), the base film is a manufactured (meth) acrylic resin film layer. And the produced film layer (B) may be bonded together using an adhesive, or may be manufactured by a coextrusion method or the like without using an adhesive. When the base film is formed of a plurality of films, the base film is obtained by molding by the above-described film molding method as in the case of the alicyclic structure-containing polymer film layer.

  When the (meth) acrylic resin is an ultraviolet curable resin, examples of the ultraviolet curable resin component include urethane acrylate, epoxy acrylate, and polyester acrylate that have an affinity with a urethane resin layer described later. An ultraviolet curable resin component is preferred.

  Moreover, as a suitable ultraviolet curable resin component used by this invention, the resin which contains the prepolymer, oligomer, and / or monomer which have a polymerizable unsaturated bond or an epoxy group in a molecule | numerator, and is hardened | cured by ultraviolet irradiation is mentioned. . Examples of prepolymers and oligomers having polymerizable unsaturated bonds or epoxy groups in the molecule include unsaturated polyesters such as a condensation product of unsaturated dicarboxylic acid and polyhydric alcohol; polyester methacrylate, polyether methacrylate, polyol methacrylate, Examples thereof include methacrylates such as melamine methacrylate, polyester acrylates, epoxy acrylates, urethane acrylates, polyether acrylates, polyol acrylates, acrylates such as melamine acrylate, and cationic polymerization type epoxy compounds.

Examples of monomers having a polymerizable unsaturated bond or epoxy group in the molecule include styrene monomers such as styrene and α-methylstyrene; methyl acrylate, ethyl acrylate, -2-ethylhexyl acrylate, methoxyethyl acrylate Acrylates such as butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, and phenyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, phenyl methacrylate Methacrylic acid esters such as lauryl methacrylate; acrylic acid-2- (N, N-diethylamino) ethyl, acrylic acid-2- (N, N-dimethylamino) ethyl, acrylic acid-2- (N, N- Dibenzylamino) methyl, acrylic acid -Unsaturated substituted amino alcohol esters such as (N, N-diethylamino) propyl; unsaturated carboxylic acid amides such as acrylamide and methacrylamide; ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, ethylene glycol diacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, 2-hydroxy acrylate, 2-hexyl acrylate, phenoxyethyl acrylate, ethylene Glycol diacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate Polyfunctional acrylates such as pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate; trimethylolpropane trithioglycolate, trimethylolpropane trithiopropylate, pentaerythritol Polythiols having two or more thiol groups in the molecule, such as tetrathioglycolate; glycidyl acrylate, glycidyl methacrylate, glycidyl phenyl ether, glycidyl ethyl ether, epichlorohydrin, allyl glycidyl ether, ethylene oxide, propylene oxide , Neopentyl glycol diglycidyl ether, trimethylolpropane diglycidyl ether, Roll diglycidyl ether, diglycerol triglycidyl ether, diglycerol triglycidyl ether, pentaerythritol diglycidyl ether, pentaerythritol triglycidyl ether, diglycidyl ether of tris (2-hydroxyethyl) isocyanurate, phenol novolac polyglycidyl ether, cresol Epoxy compounds such as novolac polyglycidyl ether can be mentioned.
In the present invention, these prepolymers, oligomers and / or monomers can be used singly or in combination of two or more.

  The content of the prepolymer, oligomer and / or monomer in the ultraviolet curable resin component used in the present invention is preferably 5% by weight to 95% by weight from the viewpoint of obtaining excellent coating suitability. A suitable ultraviolet curable resin component used in the present invention contains a photopolymerization initiator and a photopolymerization accelerator. Photopolymerization initiators include radical polymerizable initiators such as acetophenones, benzophenones, thioxanthones, acylphosphine oxides, benzoin ethers, oxime esters; aromatic diazonium salts, aromatic sulfonium salts, aromatic iodonium And cationic polymerization initiators such as salts, metathelone compounds, and benzoin sulfonates. These can be used individually by 1 type or in combination of 2 or more types. The content of the photopolymerization initiator is usually 0.1% by weight to 10% by weight in the ultraviolet curable resin component.

  The ultraviolet curable resin component can be applied in the form of a solution as necessary. Here, examples of the solvent include alcohols such as methanol, ethanol, isopropanol, n-butanol, and isobutanol; ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monobutyl ether, diacetone glycol Glycols such as propylene glycol monomethyl ether; aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as n-hexane and n-heptane; esters such as ethyl acetate and butyl acetate; methyl ethyl ketone and methyl isobutyl Ketones such as ketones; oximes such as methyl ethyl ketoxime; and combinations of two or more thereof; and the like.

  In order to add various functions to the (meth) acrylic resin film layer in an auxiliary manner, an ultraviolet-curing resin component, an antioxidant, an ultraviolet absorber, a light stabilizer, a colorant such as a dye or pigment, and a plasticizer Further, a lubricant, a surfactant and the like may be mixed.

  The method for coating the ultraviolet curable resin component on the film layer (B) is not particularly limited, and a known coating method can be employed. Specific coating methods include wire bar coating, dipping, spraying, spin coating, roll coating, gravure coating, air knife coating, curtain coating, slide coating, and extrusion coating. Can be mentioned. The coating amount of the ultraviolet curable resin component is not particularly limited, but the thickness after curing is usually 0.05 to 50 μm, preferably 0.1 to 20 μm, more preferably 0.5 to 10 μm.

  As the film layer (B) used in the present invention, it is preferable to use a film layer subjected to surface modification treatment on one side or both sides. By performing the surface modification treatment, the adhesion with the (meth) acrylic resin film layer can be improved. Examples of the surface modification treatment include energy beam irradiation treatment and chemical treatment. Examples of the energy ray irradiation treatment include corona treatment, plasma treatment, electron beam irradiation treatment, and ultraviolet ray irradiation treatment. From the viewpoint of processing efficiency, corona treatment and plasma treatment are preferred, and corona treatment is particularly preferred. Examples of the chemical treatment include a method of immersing in an aqueous solution of an oxidizing agent such as potassium dichromate solution or concentrated sulfuric acid and then washing with water.

The ultraviolet rays irradiated by the ultraviolet irradiation device may be those having a wavelength of usually 100 to 400 nm. The output value of the lamp is usually 120 to 240 w, and preferably 160 to 200 w. The dose of ultraviolet rays is against ultraviolet irradiation object, when expressed in a total amount of integrated light quantity of ultraviolet light, preferably 100~2,000mJ / cm ^2, more preferably, 200~1,500mJ / cm ^2, and most preferably Is 300 to 1,000 mJ / cm ² . The total amount of integrated light quantity is a value determined by the illuminance of the ultraviolet irradiation lamp and the line speed (film moving speed), and is measured by, for example, an ultraviolet integrated illuminometer (EYEUV METER UVPF-A1).

  The ultraviolet irradiation is preferably performed in an inert gas atmosphere, for example, in a nitrogen gas atmosphere in which the oxygen concentration is 500 ppm or less, preferably 100 ppm or less. When UV irradiation is performed in an inert gas atmosphere, the photopolymerization initiator can be greatly reduced compared to the curing of UV-curable resin components in the air, and a (meth) acrylic resin film layer with excellent weather resistance It is possible to design. In addition, since photopolymerization initiators are generally expensive, reducing the amount used is effective in reducing costs.

  Moreover, in this invention, you may apply | coat an ultraviolet curable resin component, after forming a primer layer in a film layer (B). Thereby, the adhesiveness of a (meth) acrylic-type resin film layer may be improved further. The material constituting the primer layer includes polyester urethane resin, polyether urethane resin, polyisocyanate resin, polyolefin resin, resin having hydrocarbon skeleton and / or polybutadiene skeleton in the main chain, polyamide resin, acrylic resin, polyester resin, chloride Examples thereof include vinyl-vinyl acetate copolymer, chlorinated rubber, cyclized rubber, and modified products in which polar groups are introduced into these polymers. The thickness of the primer layer is not particularly limited, and is usually 0.3 to 5 μm, preferably 0.5 to 2 μm.

  The film layer (A) used in the present invention preferably has a total light transmittance of 80% or more in terms of 1 mm thickness. More preferably, the total light transmittance is 90% or more. Further, the film layer (A) used in the present invention preferably has a haze at a thickness of 1 mm of 0.3% or less. More preferably, the haze is 0.2% or less. If the haze exceeds 0.3%, the transparency of the film layer (A) may be lowered.

  The average thickness of the film layer (A) used for this invention can be suitably selected by the relationship with the thickness of a film layer (B), and is 5 micrometers-500 micrometers normally, Preferably it is 20-300 micrometers. The thickness variation is preferably within ± 3% of the average thickness over the longitudinal direction and the width direction. By setting the thickness variation within the above range, variations in optical characteristics such as Re of the film layer (A) and the film layer (B) of the present invention can be reduced.

  The film layer (A) used in the present invention has an in-plane retardation Re variation within 10 nm, preferably within 5 nm, and more preferably within 2 nm. By setting the variation of the in-plane retardation Re within the above range, the display quality can be improved when used as a retardation film for a liquid crystal display device. Here, the variation in the in-plane retardation Re is the in-plane retardation Re in the width direction of the film when the light incident angle is 0 ° (incident light beam and the surface of the film layer (A) of the present invention are orthogonal). This is the difference between the maximum value and the minimum value of the in-plane retardation Re when measured.

  When the film layer (A) used in the present invention is a stretched film (stretched film layer (A)), the values of in-plane retardation Re and thickness direction retardation Rth vary depending on the display design. The in-plane retardation Re is appropriately selected from the range of about 10 to 500 nm and the thickness direction retardation Rth of about −500 to 500 nm. The in-plane retardation Re in the present invention is the refractive index nx in the slow axis direction of the stretched film layer (A), the refractive index ny in the direction perpendicular to the slow axis in the plane, and the refractive index nz in the thickness direction. When the average thickness D of the film is taken, it is a value defined by (nx−ny) × D, and the thickness direction retardation Rth in the present invention is defined by ((nx + ny) / 2−nz) × D. Is the value to be

  The content of the residual volatile component in the film layer (A) used in the present invention is not particularly limited, but is preferably 0.1% by weight or less, more preferably 0.05% by weight or less, and further preferably 0.02% by weight. It is as follows. If the content of the residual volatile component exceeds 0.1% by weight, the optical characteristics of the film layer (A) in the present invention may change over time. By making the content of the volatile component in the above range, the dimensional stability is improved, the in-plane retardation Re or Rth of the film layer (A) can be reduced, and the film layer (A ), The deterioration of the polarizing plate and the liquid crystal display device can be suppressed, and the display on the display can be kept stable and good for a long time. The volatile component is a substance having a molecular weight of 200 or less contained in a trace amount in the film layer (A) in the present invention, and examples thereof include residual monomers and solvents. The content of the volatile component can be quantified by analyzing the film layer (A) in the present invention by gas chromatography as a total of substances having a molecular weight of 200 or less.

  It is preferable that the film layer (A) used for this invention is elongate. The long shape means one having a length of at least about 5 times the width direction of the film, preferably 10 times or more, and specifically wound in a roll shape. It has a length that can be stored or transported.

The film layer (A) used in the present invention (including the stretched film layer (A) as the film layer (A)) is subjected to surface modification treatment before the urethane resin layer is provided, and the film layer (A ) Surface average water contact angle is preferably in the range of 20 to 50 degrees, and the standard deviation of the water contact angle is preferably 0.01 to 5 degrees. The standard deviation in the present invention is a sample standard deviation. The water contact angle is determined by the θ / 2 method using a contact angle meter. The average water contact angle is calculated by measuring the 20 water contact angles randomly selected within the range of 100 cm ² in the film layer (A) subjected to the surface modification treatment, and calculating the average of these measured values. The The standard deviation of the water contact angle is calculated from this measured value. By performing the surface modification treatment, functional groups such as a hydroxy group, a carboxyl group, a carbonyl group, an amino group, and a sulfone group can be introduced on the surface of the film layer (A). Therefore, when the aqueous dispersion of the aqueous urethane resin is applied to the surface of the film layer (A), the aqueous dispersion of the aqueous urethane resin is adapted to the surface of the film layer (A) and can be applied uniformly. Therefore, a urethane resin layer having a uniform thickness can be formed on the surface of the film layer (A). Examples of the surface modification treatment include corona treatment, plasma treatment, ultraviolet irradiation treatment, and saponification treatment. From the viewpoint of processing efficiency, corona treatment and plasma treatment are preferred, and corona treatment is particularly preferred. When the film layer (A) is formed of an acrylic resin, it is preferable to saponify the surface of the film layer (A).

  The corona treatment used in the present invention is preferably a wire electrode, a plane electrode, or a roll electrode as the electrode structure, but in order to make the discharge uniform, a dielectric is sandwiched between the base film and the electrode. It is preferable to carry out the treatment at

  As the material of the electrode, metals such as iron, copper, aluminum, and stainless steel can be used. As the electrode shape, electrodes such as a thin plate shape, a knife edge shape, and a brush shape can be used.

  The dielectric preferably has a relative dielectric constant of 10 or more, and has a structure in which a dielectric is sandwiched between upper and lower electrodes. Dielectric materials include ceramics, silicone rubber, polytetrafluoroethylene, polyethylene terephthalate and other plastics, glass, quartz, silicon dioxide, aluminum oxide, zirconium dioxide, titanium dioxide and other metal oxides, and compounds such as barium titanate. Is mentioned. In particular, interposing a solid dielectric having a relative dielectric constant of 10 or more (in an environment of 25 ° C.) is advantageous in that corona treatment can be performed at a high speed with a low voltage. Examples of the solid dielectric having a relative dielectric constant of 10 or more include metal oxides such as zirconium dioxide and titanium dioxide, oxides such as barium titanate, and silicon rubber. The dielectric thickness is preferably in the range of 0.3 to 1.5 mm. If the thickness of the dielectric is too thin, dielectric breakdown is likely to occur, and if it is too thick, the applied voltage needs to be increased, resulting in poor efficiency.

  The distance between the base film and the electrode is preferably 0.5 to 10 mm. If the thickness is less than 0.5 mm, only a thin film of the base film can pass, and if there is a seam, the base film may hit the electrode when passing, and the base film may be damaged. Moreover, since an applied voltage will become high when it exceeds 10 mm, a power supply becomes large and discharge will become a streamer shape.

  The output of the corona treatment used in the present invention is preferably a condition for treating as little damage as possible on the surface of the film layer (A), specifically 0.02 to 5 kW, preferably 0.04 to 2 kW. More preferably. Also, the best corona treatment method is to perform the corona treatment several times within the above range at the lowest possible output.

The density of the corona treatment used in the present invention is not limited as long as the average water contact angle of the film layer (A) is 20 to 50 degrees and the standard deviation of the water contact angle is within the range of 0.01 to 5 degrees. Specifically, it is preferably a 1~1000W · min / m ^2, more preferably 5~500W · min / m ^2, further preferably 10~300W · min / m ^2. When the treatment density is low, the applicability of the aqueous dispersion of the water-based urethane resin is lowered. Moreover, when high, the surface of a film layer (A) will be destroyed and adhesiveness will fall.

  The frequency of the corona treatment used in the present invention is preferably 5 to 100 kHz, and more preferably 10 to 50 kHz. When the frequency is lowered, the uniformity of the corona discharge treatment is deteriorated, and unevenness of the corona discharge treatment occurs. In addition, when the frequency is increased, there is no particular problem when performing a high-output corona discharge treatment, but when performing a low-output corona discharge treatment, it becomes difficult to perform a stable treatment. Unevenness occurs.

  In the corona treatment used in the present invention, the discharge can be generated in a finer state by surrounding the electrode with a casing, putting an inert gas inside the casing, and applying gas to the electrode portion. As the inert gas, helium, argon, or nitrogen can be used.

  Examples of the plasma treatment used in the present invention include glow discharge treatment and flame plasma treatment. As the glow discharge, either a vacuum glow discharge process performed under vacuum or an atmospheric pressure glow discharge process performed under atmospheric pressure can be used, but an atmospheric pressure glow discharge process performed under atmospheric pressure is preferable from the viewpoint of productivity. . In addition, the atmospheric pressure in this invention is the range of 700-780 Torr. In the glow discharge treatment, a film layer (A) is placed between opposing electrodes, a plasma-exciting gas is introduced into the apparatus, and a high-frequency voltage is applied between the electrodes, whereby the gas is plasma-excited. In this case, glow discharge is performed. Thereby, the surface of a film layer (A) is processed and the hydrophilicity of the surface of a film layer (A) is improved.

  The plasma-excitable gas refers to a gas that is plasma-excited under the above conditions. Plasma-excitable gases include chlorofluorocarbons such as argon, helium, neon, krypton, xenon, nitrogen, carbon dioxide, tetrafluoromethane and mixtures thereof, and inert gases such as argon and neon, carboxyl groups and hydroxyl groups. And a reactive gas capable of imparting a polar functional group such as a carbonyl group.

  The frequency of the high-frequency voltage is preferably in the range of 1 kHz to 100 kHz, and the magnitude of the voltage is preferably in a range in which the electric field strength when applied to the electrode is 1 to 100 kV / cm.

  The saponification treatment used in the present invention is an alkali saponification treatment. Examples of the treatment method include an immersion method and an alkaline solution coating method, but the immersion method is preferable from the viewpoint of productivity.

  The immersion method is a technique in which a base film is immersed in an alkaline solution under appropriate conditions, and all surfaces having reactivity with alkali on the entire surface of the base film are saponified, and special equipment is required. Therefore, it is preferable from the viewpoint of cost. The alkaline liquid is preferably a sodium hydroxide aqueous solution. The concentration is preferably from 0.5 to 3 mol / l, more preferably from 1 to 2 mol / l. The liquid temperature of the alkaline liquid is preferably 25 to 70 ° C, more preferably 30 to 60 ° C. The treatment time may be adjusted as appropriate as long as the average water contact angle of the film layer (A) is 20 to 50 degrees and the standard deviation of the water contact angle is within the range of 0.01 to 5 degrees.

  After being immersed in the alkali solution, it is preferable to sufficiently wash with water or neutralize the alkali component by immersing in a dilute acid so that the alkali component does not remain in the base film.

Although there is no restriction | limiting in particular as thickness of a base film, From the viewpoint of material cost, thickness reduction, and weight reduction, the thickness is 1-1000 micrometers normally, 5-300 micrometers is preferable, and it is 30-150 micrometers, and more preferable.

  The urethane resin layer in the present invention is neutralized on the surface of the surface-modified film layer (A) (including the surface-modified stretched film layer (A) as the film layer (A)). It can be obtained by directly applying an aqueous dispersion of an aqueous urethane resin after the treatment. The aqueous dispersion of the aqueous urethane resin after the neutralization treatment is formed by dispersing the aqueous urethane resin after the neutralization treatment in water, and can take the form of an emulsion, a colloidal dispersion system, an aqueous solution, or the like.

  The post-neutralization aqueous urethane resin can be obtained by neutralizing at least a part of the acid structure contained in the acid structure-containing aqueous urethane resin with a non-volatile base. The laminated film of the present invention produced using an aqueous dispersion containing a water-based urethane resin after neutralization treatment, while maintaining the properties as an optical material, even if it has a thermal history exposed to high temperatures, When used by being laminated on another optical film, particularly a polarizer, the adhesion between the laminated film and the other optical film can be kept good. Examples of the water-based urethane resin include (i) a water-based urethane resin obtained by reacting a component containing an average of two or more active hydrogens in one molecule and (ii) a polyvalent isocyanate component, or the above (i) Component (ii) is subjected to a urethanation reaction in an organic solvent that is inert to the reaction and has a high affinity for water under the condition of excess isocyanate groups to obtain an isocyanate group-containing prepolymer, and then neutralizing the prepolymer And water-based urethane resin produced by chain extension using a chain extender and adding water to form a dispersion.

  The chain extension method of the isocyanate group-containing prepolymer may be a known method. For example, water, a water-soluble polyamine, glycols or the like is used as the chain extender, and the isocyanate group-containing prepolymer and the chain extender component are used. May be reacted in the presence of a catalyst as necessary.

  The component containing an average of 2 or more active hydrogens in one molecule of the component (i) is not particularly limited, but preferably has a hydroxylic active hydrogen. Specific examples of such compounds include the following.

(1) Diol compound:
Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol 1,6-hexane glycol, 2,5-hexanediol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, tricyclodecane dimethanol, 1,4-cyclohexane dimethanol and the like.

(2) Polyether diol:
Alkylene oxide adducts of the above diol compounds, ring-opening (co) polymers such as alkylene oxides and cyclic ethers such as tetrahydrofuran, such as polyethylene glycol, polypropylene glycol, copolymers of ethylene glycol-propylene glycol, glycol, polytetramethylene glycol , Polyhexamethylene glycol, polyoctamethylene glycol and the like.

(3) Polyester diol:
Dicarboxylic acid such as adipic acid, succinic acid, sebacic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid or the like and ethylene glycol, propylene glycol, 1,4-butane as mentioned in (1) above Examples thereof include those obtained by polycondensation with a diol compound such as diol, 1,6-hexanediol, 1,8-octamethylenediol, neopentylglycol and the like under hydroxyl group-excess conditions. Specifically, ethylene glycol-adipic acid condensate, butanediol-adipine condensate, hexamethylene glycol-adipic acid condensate, ethylene glycol-propylene glycol-adipic acid condensate, or lactone ring opening using glycol as an initiator. Examples thereof include polymerized polylactone diol.

(4) Polyether ester diol:
An ether group-containing diol (polyether diol or diethylene glycol of (2) above) or a mixture of this with another glycol is added to the dicarboxylic acid or anhydride thereof exemplified in (3) above to react with the alkylene oxide. For example, polytetramethylene glycol-adipic acid condensate.

(5) Polycarbonate diol:
General formula HO-R- (OC (O) -O-R) x-OH (wherein R is a saturated fatty acid diol residue having 1 to 12 carbon atoms, x is the number of repeating units of the molecule) And is usually an integer of 5 to 50). These include a transesterification method in which a saturated aliphatic diol and a substituted carbonate (diethyl carbonate, diphenyl carbonate, etc.) are reacted under the condition that the hydroxyl group is excessive, the saturated aliphatic diol and phosgene are reacted, or as necessary. Then, it can be obtained by a method of further reacting with a saturated aliphatic diol.

  The compounds as exemplified in the above (1) to (5) can be used alone or in combination of two or more.

  As the polyisocyanate component (ii) to be reacted with the component (i), an aliphatic, alicyclic or aromatic compound containing an average of two or more isocyanate groups in one molecule can be used.

  The aliphatic diisocyanate compound is preferably an aliphatic diisocyanate having 1 to 12 carbon atoms, and examples thereof include hexamethylene diisocyanate and 2,2,4-trimethylhexane diisocyanate. The alicyclic diisocyanate compound is preferably an alicyclic diisocyanate having 4 to 18 carbon atoms, and examples thereof include 1,4-cyclohexane diisocyanate and methylcyclohexylene diisocyanate. Examples of the aromatic isocyanate include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylene diisocyanate.

  In the production method of the present invention, a post-neutralization aqueous urethane resin obtained by neutralizing at least a part of the acid structure of the acid structure-containing aqueous urethane resin with a nonvolatile base is used. A resin obtained by neutralizing the acid structure of an acid structure-containing water-based urethane resin with a base can be used in water without using a surfactant (hereinafter also referred to as an emulsifier) or in a small amount. Since it can be dispersed, the water resistance of the coating film is improved, the adhesiveness is excellent, and high transparency can be maintained, which is preferable. The content of the acid structure is preferably in the range of 25 to 250 mgKOH / g, preferably 30 to 150 mgKOH / g, as the acid value in the water-based urethane resin. If the acid value is less than 25, water dispersibility tends to be insufficient, and it is often necessary to use a surfactant. On the other hand, if the acid value is more than 250 mgKOH / g, the water resistance of the coating film tends to be inferior.

Examples of the acid structure in the acid structure-containing aqueous urethane resin used in the present invention include an acid group including a carboxyl group (—COOH) and a sulfo group (—SO ₃ H). The acid structure may be present in the side chain or terminal in the acid structure-containing aqueous urethane resin.

  As a method for introducing an acid structure into a water-based urethane resin, a conventionally used method can be used without any particular limitation. For example, dimethylolalkanoic acid is a part of the glycol component described in (2) to (4) above. Alternatively, a method of introducing an acid structure by introducing a carboxyl group into polyether diol, polyester diol, polyether ester diol or the like in advance by replacing all of them is preferable. Examples of the dimethylolalkanoic acid used here include dimethylolacetic acid, dimethylolpropionic acid, and dimethylolbutyric acid.

  In the post-neutralization aqueous urethane resin used in the present invention, at least a part of the acid structure of the acid structure-containing aqueous urethane resin is neutralized with a nonvolatile base. It is preferable that 20% or more of the acid structure of the acid structure-containing aqueous urethane resin is neutralized with a nonvolatile base, and it is particularly preferable that 50% or more is neutralized with a nonvolatile base. 20% or more of the acid structure is neutralized by a non-volatile base, so that even if the laminated film of the present invention has a heat history exposed to high temperatures, while maintaining the properties as an optical material, When used by being laminated on another optical film, in particular, a polarizer, the adhesion with the laminated film can be further maintained. The post-neutralization aqueous urethane resin used in the present invention is only required that at least a part of the acid structure of the acid structure-containing aqueous urethane resin is neutralized by a non-volatile base, and the remaining acid structure is medium. It may not be summed or may be neutralized with a volatile base.

  As the non-volatile base, after the neutralization-treated aqueous urethane resin aqueous dispersion used in the present invention was applied to the surface of the base film and then dried, it was left at, for example, 80 ° C. for 1 hour. In some cases, mention may be made of inorganic and organic bases which are substantially non-volatile. Examples of the substantially non-volatile inorganic base and organic base include a case where the decrease of the non-volatile base after the treatment is 80% or less. As such a non-volatile base, an organic base is preferable, an organic base having a boiling point of 100 ° C. or higher is preferable, an amino compound having a boiling point of 100 ° C. or higher is more preferable, and an amine compound having a boiling point of 200 ° C. or higher is particularly preferable. The organic base may be a low molecular compound or a polymer.

  Examples of the non-volatile base include an inorganic base such as sodium hydroxide or potassium hydroxide, or 2-amino-2-methyl-1-propanol (AMP), triethanolamine, triisopropanolamine (TIPA), and monoethanolamine. , Diethanolamine, tri [(2-hydroxy) -1-propyl] amine, 2-amino-2-methyl-1,3-propanediol (AMPD) and 2-amino-2-hydroxymethyl-1,3-propane water Potassium oxide, zinc ammonium complex, copper ammonium complex, silver ammonium complex, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β (Aminoethyl) -γ-aminopropyltrimethyl Dimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N, N-bis (trimethylsilyl) urea, 3-ureidopropyltrimethoxysilane, 3-aminopropyl-tris (2-methoxy-ethoxy-ethoxy) silane N-methyl-3-aminopropyltrimethoxycarboxylic acid dihydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, Picoline, pyridine, morpholine, piperazine, cyclohexylamine, hexamethylenediamine, N, N-dimethylformamide, ethylenediamine, diethylenetriamine, tetraethylene Pentamine, pentaethylenepentamine, monoethanolamine, diethanolamine, ilopropanolamine, N, N-diethylmethanolamine, N, N-dimethylethanolamine, aminoethylethanolamine, N-methyl-N-N-diethanolamine, 1, 2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4′-dicyclohexylmethanediamine, 3,3′-dimethyl-dicyclohexylmethanediamine, 1,2-cyclohexanediamine, 1,4-cyclohexanediamine, aminoethylethanolamine, aminopropylethanolamine, aminohexylethanolamine, aminoethylpropanolamine, Minopropylpropanolamine, aminohexylpropanolamine, diethylenetriamine, dipropylenetriimidazole, 1- (2-aminoethyl) -2-methylimidazole, 1- (2-aminoethyl) -2-ethylimidazole, 2-aminoimidazole sulfate 2- (2-aminoethyl) -benzimidazole, pyrazole, 5-aminopyrazole, 1-methyl-5-aminopyrazole, 1-isopropyl-5-aminopyrazole, 1-benzyl-5-aminopyrazole, 1,3 -Dimethyl-5-aminopyrazole, 1-isopropyl-3-methyl-5-aminopyrazole, 1-benzyl-3-methyl-5-aminopyrazole, 1-methyl-4-chloro-5-aminopyrazole, 1-methyl -4-Acino-5-amino Pyrazole, 1-isopropyl-4-chloro-5-aminopyrazole, 3-methyl-4-chloro-5-aminopyrazole, 1-benzyl-4-chloro-5-aminopyrazole, 1,3-dimethyl-4-chloro -Amino resins, such as a melamine resin, a urea resin, a guanamine resin, can be mentioned.

  As the post-neutralization water-based urethane resin used in the present invention, the number average molecular weight is preferably 1,000 or more, more preferably 20,000 or more. However, it is preferably 1,000,000 or less, more preferably 200,000 or less. The number average molecular weight of the post-neutralization aqueous urethane resin obtained by neutralizing the acid structure-containing aqueous urethane resin having the number average molecular weight in the above range is also within the above range.

  The particle size of the post-neutralization water-based urethane resin particles dispersed in the aqueous dispersion in the present invention is preferably 0.01 μm to 0.4 μm from the viewpoint of film optical properties. The particle size of the water-based urethane resin particles after the neutralization treatment can be measured by a dynamic light scattering method, and for example, can be measured by a light scattering photometer DLS-8000 series manufactured by Otsuka Electronics Co., Ltd. The aqueous dispersion of the post-neutralization aqueous urethane resin in the present invention may contain a water-soluble solvent. Examples of the water-soluble solvent include methanol, ethanol, isopropyl alcohol, acetone, tetrahydrofuran, N-methylpyrrolidone, dimethyl sulfoxide, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, and the like.

  The viscosity of the aqueous dispersion of the water-based urethane resin after neutralization treatment in the present invention is preferably 15 mPa · s or less, and particularly preferably 10 mPa · s or less. When the viscosity of the aqueous dispersion is within the above range, the aqueous dispersion can be applied thinly and uniformly on the surface of the film layer (A). The viscosity of the aqueous dispersion is a value measured under a condition of 25 ° C. using a tuning fork type vibration viscometer, and the ratio of the post-neutralization aqueous urethane resin and the post-neutralization aqueous urethane resin in the aqueous dispersion. The viscosity of the aqueous dispersion can be adjusted by changing the particle size of the water dispersion.

  As said acid structure containing water-based urethane resin, you may replace the base currently used for neutralization of the acid structure of water-based urethane resin by adding the non-volatile base mentioned above to commercially available water-based urethane resin. Confirmation of the base exchange can be easily confirmed by using an analytical method such as 1H-NMR, 13C-NMR, etc. after isolating the exchanged resin. Examples of the commercially available water-based urethane resins include “Adekabon titer” series manufactured by Asahi Denka Kogyo Co., Ltd., “Olestar” series manufactured by Mitsui Toatsu Chemicals, Ltd., Dainippon Ink & Chemicals, Inc. ) “Bondic” series, “Hydran” series, Bayer's “Imperil” series, “Sofuranate” series made by Sofran Japan, “Poise” series made by Kao Corporation, Sanyo Chemical Industries ( "Samprene" series manufactured by Co., Ltd., "Izelux" series manufactured by Hodogaya Chemical Co., Ltd., "Superflex" series manufactured by Daiichi Kogyo Seiyaku Co., Ltd., "Neolet's" series manufactured by Geneca Co., Ltd., etc. Can be used.

  When the thickness of the urethane resin layer formed on the film layer (A) is 1 μm or less, a crosslinking agent is preferably included in the urethane resin layer for the purpose of improving the mechanical strength of the urethane resin layer. The crosslinking agent that can be used in the present invention can be used without particular limitation as long as it has a functional group that reacts with the reactive group of the aqueous urethane resin after neutralization treatment. It is preferable to use a compound, a water-based isocyanate compound, and a water-based carbodiimide compound from the viewpoint of versatility of the material, and it is particularly preferable to use a water-based epoxy compound and a water-based amino compound from the viewpoint of adhesiveness.

  The water-based epoxy compound may be any compound that is soluble in water or has two or more epoxy groups emulsified. For example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol; 1 mol of glycol such as 1,4-butanediol, 1,6-hexane glycol, neopentyl glycol and 2 mol of epichlorohydrin Diepoxy compounds obtained by etherification, polyepoxy compounds obtained by etherification of 1 mol of polyhydric alcohols such as glycerin, polyglycerin, trimethylolpropane, pentaerythritol, sorbitol and 2 mol or more of epichlorohydrin, phthalic acid, terephthalic acid Epoxy compounds such as diepoxy compounds obtained by esterification of 1 mol of dicarboxylic acid such as oxalic acid and adipic acid and 2 mol of epichlorohydrin. It is.

  The aqueous amino compound may be any compound that is soluble in water or has two or more amino groups emulsified. For example, carbodihydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, acrylic acid dihydrazide, etc. A compound, a melamine resin, a urea resin, a guanamine resin, etc. are mentioned.

  The water-based isocyanate compound may be a compound that has solubility in water or has two or more non-blocked isocyanate groups and block-type isocyanate groups emulsified. Examples of the non-blocking isocyanate compound include compounds obtained by reacting a polyfunctional isocyanate compound with a monovalent or polyvalent nonionic polyalkylene ether alcohol. As the block type isocyanate compound, 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), 4,4′-diphenylmethane diisocyanate (MDI), xylylene diene Isocyanate (XDI), isophorone diisocyanate (IPDI), methylcyclohexyl diisocyanate (H6TDI), 4,4'-dicyclohexylmethane diisocyanate (H12MDI), 1,3-bis (isocyanatomethyl) cyclohexane (H6XDI), tetramethylxylylene diisocyanate (TMXDI), 2,2,4-trimethylhexamethylene diisocyanate (TMHDI), hexamethylene diisocyanate (HDI), norbornene diisocyanate (NBDI), 2, 4,6-triisopropylphenyl diisocyanate (TIDI), 1,12-diisocyanatododecane (DDI), 2,4, -bis- (8-isocyanatooctyl) -1,3-dioctylcyclobutane (OCDI), n-pentane- 1,4-diisocyanates and their isocyanurate-modified products, adduct-modified products, burette-modified products, allophanate-modified products, and polymers having one or more isocyanate groups are modified with polyoxyalkylene groups, carboxyl groups, etc. And a compound obtained by making it water-soluble and / or water-dispersible and masking an isocyanate group with a blocking agent (phenol, ε-caprolactam, etc.).

  The water-based carbodiimide compound may be any compound that is soluble in water or has two or more carbodiimide bonds (—N═C═N—) emulsified. A compound having two or more carbodiimide bonds is obtained by a method in which two isocyanate groups are decarboxylated to form -N = C = N- using two or more molecules of polyisocyanate and a carbodiimidization catalyst. be able to. The polyisocyanate and the carbodiimidization catalyst used when producing a compound having two or more carbodiimide bonds are not particularly limited, and conventionally known ones can be used.

  The ratio of the post-neutralization water-based urethane resin and the crosslinking agent is 1 to 30 parts by weight, preferably 5 to 15 parts by weight of the cross-linking agent with respect to 100 parts by weight (solid content) of the post-neutralization water-based urethane resin. It is preferable to blend (solid content). By using the above formulation, it is possible to achieve both the strength of the coating film formed from the aqueous dispersion and the stability of the coating liquid.

  The urethane resin layer in the present invention preferably has a pencil hardness of H or more at a thickness of 20 μm. By setting it in the above range, scratch resistance can be imparted to the laminated film.

  The urethane resin layer in the present invention preferably has a surface static friction coefficient and a dynamic friction coefficient of 0.6 or less, preferably 0.4. By setting it in the above range, scratch resistance can be imparted to the laminated film.

  In the urethane resin layer in the present invention, if necessary, heat stabilizer, weather stabilizer, leveling agent, antistatic agent, slip agent, antiblocking agent, antifogging agent, lubricant, dye, pigment, natural oil, synthetic An appropriate amount of other compounding agents such as oil, wax, and crosslinking agent may be added.

  The urethane resin layer can be formed by coating the aqueous dispersion on one side or both sides of the film layer (A) subjected to surface modification treatment.

  The method of apply | coating the water dispersion containing a water-based urethane resin after neutralization process on a film layer (A) is not specifically limited, A well-known coating method is employable. Specific coating methods include wire bar coating, dipping, spraying, spin coating, roll coating, gravure coating, air knife coating, curtain coating, slide coating, and extrusion coating. Can be mentioned. The coating amount of the aqueous dispersion of the aqueous urethane resin after the neutralization treatment is not particularly limited, but the thickness after drying is preferably 0.01 to 5 μm, more preferably 0.02 to 4 μm, and particularly preferably 0.03 to 3 μm. preferable. Within the above range, sufficient adhesive strength between the film layer (A) and the urethane resin layer can be obtained, and a laminated film free from defects such as warping of the film can be provided.

  The film layer (A) and the urethane resin layer in the present invention preferably have an interface refractive index difference of 0.05 or less. When the difference in interface refractive index is within the above range, it is possible to suppress light loss when light is transmitted through the laminated film of the present invention.

  When the film layer (A) is provided on one side of the base film, the urethane resin layer is provided on the surface of the film layer (A), and the film layer (A) is provided on both sides of the base film. Can be provided on both sides of the substrate film. By providing it on both sides of the base film, web handling can be improved in the case of a long film.

  The laminated film according to the present invention is produced into a polarizing plate by further laminating a polarizer on the surface of the urethane resin layer in the laminated film, and the present invention is provided via an adhesive on at least one surface of the polarizer. It can manufacture by laminating | stacking this laminated film. The laminated film according to the present invention has excellent durability because it has good adhesiveness with a polarizer while maintaining its properties as an optical material even if it has a thermal history exposed to high temperatures. Can be provided. When the laminated film of the present invention is laminated only on one side of the polarizer, a highly transparent film may be laminated on the other side of the polarizer. The polarizing plate is also referred to as a polarizing film or a polarizing sheet.

  The polarizer can be obtained by adsorbing iodine or dichroic dye on a polyvinyl alcohol film and then uniaxially stretching in a boric acid bath, and adsorbing iodine or dichroic dye on a polyvinyl alcohol film. And stretching, and a part of the polyvinyl alcohol unit in the molecular chain can be modified to a polyvinylene unit. A polarizer having a function of separating polarized light into reflected light and transmitted light, such as a grid polarizer, a multilayer polarizer, and a cholesteric liquid crystal polarizer, can also be used as the polarizer. Among these, a polarizer comprising polyvinyl alcohol is preferable. The polarization degree of the polarizer is preferably 98% or more, more preferably 99% or more. The thickness (average thickness) of the polarizer is preferably 5 μm to 80 μm.

  The adhesive for adhering the polarizer and the laminated film of the present invention is not particularly limited as long as it is optically transparent, and is an aqueous adhesive, a solvent-type adhesive, a two-component curable adhesive, an ultraviolet curable type. Examples thereof include an adhesive and a pressure-sensitive adhesive. Among these, a water-based adhesive is preferable, and a polyvinyl alcohol-based water-based adhesive is particularly preferable.

  The average thickness of the adhesive layer is preferably 0.05 to 5 μm, and more preferably 0.1 to 1 μm.

  As a method of laminating the laminated film of the present invention on a polarizer, a normal method can be used. After applying an adhesive to one surface of the polarizer, the polarizer and the present invention are used using a roll laminator. A method in which the laminated film is bonded to the surface on which the urethane resin layer is provided and dried. The drying time and the drying temperature are appropriately selected according to the type of adhesive.

  The laminated film of the present invention has good adhesion to, for example, a UV curable resin, or an optical film, sheet, or substrate formed with a prism shape. Besides, a film with an antireflection film, a protective film, a retardation film, a viewing angle widening film, a brightness enhancement film and the like excellent in durability can be formed.

  The laminated film of the present invention is suitably used for various image display devices such as organic EL display devices and plasma displays.

Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited to the following Example.
The test and evaluation in an Example and a comparative example were performed with the following method.

(Evaluation method)
<Optical properties of laminated film>
Based on JIS K7361-1997, the produced laminated film was measured for total light transmittance and haze of the laminated film using “Durbidity Meter NDH-300A” manufactured by Nippon Denshoku Industries Co., Ltd.
<Measurement of peel strength of polarizing plate>
The produced polarizing plate was cut into a width of 15 mm, the polarizer and the film were pulled in the 180 ° direction, and the strength was measured (measurement of 180 ° peel strength). The measurement was made with a length of 50 mm, and the average peel strength and the peel strength R (maximum value-minimum value) at that time were measured. In addition, the test was implemented at the tensile speed of 50 mm / sec using the universal tension compression tester (TCM-500CR: Shinsei Tsushin Kogyo Co., Ltd. product) as a measuring machine.
<Measurement of peel strength of polarizing plate after heat test>
The produced laminated film was left in a dryer at 80 ° C. for 1 week, and then a polarizer and a laminated film were bonded together with a roll laminator to obtain a polarizing plate. The obtained polarizing plate was cut into a width of 15 mm, and the test was carried out in the same manner as the peel strength measurement.

(Production Example 1)
<Manufacture of base film (I)>
A pellet of an alicyclic structure-containing polymer resin (ZEONOR 1430, manufactured by Nippon Zeon Co., Ltd .; glass transition temperature 135 ° C.) was dried at 70 ° C. for 2 hours using a hot air dryer in which air was circulated. Using a T-die film melt extrusion molding machine having a resin melt kneader equipped with a screw, a base film (thickness: 100 μm, length: 1000 m under molding conditions of a melt resin temperature of 270 ° C. and a T-die width of 500 mm) I) was prepared. The base film (I) is an example of the base film used in the present invention.

(Production Example 2)
<Manufacture of base film (II)>
The film layer (B) is a polystyrene resin Daylark D332 (manufactured by Nova Chemical), and the film layer (A) is ZEONOR1430 (manufactured by Nippon Zeon Co., Ltd.) pellets after drying at 100 ° C. for 5 hours, and then extruded separately. Supplied to the machine. After the resin is melted in the extruder, it is merged in the feed block through the polymer pipe and the polymer filter, extruded in a sheet form from a T-die having a width of 500 mm onto the casting drum, and cooled on the cooling drum to obtain a thickness. A multilayer film composed of A layer-B layer-A layer having a length of 140 μm and a length of 1000 m was obtained.

  Next, the produced multi-layer film having a width of 500 mm is continuously uniaxially stretched at a stretching temperature of 140 ° C. and a stretching ratio of 2.0 times using a tenter-type lateral stretching machine, and further, the left and right ends are cut and removed. By doing this, the base film (II) in which the orientation axis coincided with the width direction was obtained. The base film (II) is an example of a base film having an alicyclic structure-containing polymer film layer stretched on the outermost surface.

(Production Example 3)
<Manufacture of base film (III)>
A uniform mixture of 90.0 parts of ditrimethylolpropane tetraacrylate (NK ester AD-TMP, manufactured by Shin-Nakamura Chemical Co., Ltd.), 10.0 parts of photoinitiator (Irgacure 907, manufactured by Ciba Geigy) and 900.0 parts of butyl acetate is uniformly formed. After stirring and mixing, the mixture was filtered through a 1 μm filter to prepare an ultraviolet curable resin solution.

  Next, on both surfaces of the film (I) produced in Production Example 1, using a corona treatment device (manufactured by Kasuga Electric Co., Ltd.), an output of 300 W, a wire electrode having a diameter of 1.2 mm, an electrode length of 240 mm, and a distance between work electrodes of 3 Discharge treatment was performed once under the conditions of 0.0 mm and a conveyance speed of 4 m / min, and then the previously prepared UV curable resin solution was applied using a gravure coater to a dry film thickness of 2 μm, and 80 ° C. Then, the substrate film (III) was obtained by curing the resin by irradiating with ultraviolet rays (integrated light amount 400 mJ / cm 2) using an ultra-high pressure mercury lamp. The base film (III) is an example of a base film having a (meth) acrylic resin film layer on the outermost surface.

(Production Example 4)
<Manufacture of polarizer>
A polyvinyl alcohol film having a thickness of 80 μm is dyed in a 0.3% iodine aqueous solution, stretched up to 5 times in a 4% boric acid aqueous solution and a 2% potassium iodide aqueous solution, and then dried at 50 ° C. for 4 minutes. To obtain a polarizer.

(Production Example 5)
<Adjustment of adhesive liquid>
Goseifamer Z410 (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., PVA containing acetoacetyl group) was diluted with water to a solid content of 3% to prepare an adhesive solution.

( Reference example )
To a 2000 ml four-necked flask equipped with a thermometer, a stirrer, a nitrogen introduction tube, and a cooling tube, 840 g of a polyester polyol, Maximol FSK-2000 (manufactured by Kawasaki Chemical Industry Co., Ltd., hydroxyl value 56 mgKOH / g), tolylene 119 g of isocyanate and 200 g of methyl ethyl ketone were added and reacted at 75 ° C. for 1 hour while introducing nitrogen. After completion of the reaction, the mixture was cooled to 60 ° C., 35.6 g of dimethylolpropionic acid was added, and the mixture was reacted at 75 ° C. to obtain an acid structure-containing aqueous urethane resin solution having an NCO of 0.5%. Next, this acid structure-containing aqueous urethane resin solution was cooled to 40 ° C., 1500 g of water and 10.6 g of sodium hydroxide were added, and emulsification was performed by stirring at high speed with a homomixer. Methyl ethyl ketone was distilled off from the emulsion under reduced pressure by heating to obtain an aqueous dispersion of an aqueous urethane resin 1 after a neutralization treatment with a solid content of 40%.

  Next, using a corona treatment apparatus (Kasuga Denki Co., Ltd.), the base film (I) subjected to the discharge treatment under the conditions of an output of 300 W, an electrode length of 240 mm, a work electrode distance of 3.0 mm, and a conveying speed of 4 m / min. A coating solution obtained by adding 35 g of water to 5.0 g of aqueous dispersion 1 of water-based urethane resin 1 after neutralization was applied to the surface of the surface using a bar coater so that the dry film thickness was 2 μm. A laminated film 1 was obtained by drying at 10 ° C. for 10 minutes. The evaluation results of the laminated film 1 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 1, and the laminated film in which the laminated film 1 was allowed to stand for 1 week in a dryer at 80 ° C. were used for the roll laminator using the adhesive produced in Production Example 5. The polarizing plate 1 was obtained by bonding together. Table 1 shows the measurement results of the peel strength of the polarizing plate 1.

( Example 1 )
Other than changing sodium hydroxide, which is a neutralizing agent of the aqueous dispersion containing the post-neutralization aqueous urethane resin 1 prepared in the reference example , to monoethanolamine (boiling point: 171 ° C., blending amount: 16.1 g) Obtained the water dispersion of the water-based urethane resin 2 after the neutralization process of solid content 40% by operation similar to a reference example .

  Next, using a corona treatment apparatus (Kasuga Denki Co., Ltd.), the base film (I) subjected to the discharge treatment under the conditions of an output of 300 W, an electrode length of 240 mm, a work electrode distance of 3.0 mm, and a conveying speed of 4 m / min. On the surface of this, a neutral dispersion-treated aqueous urethane resin 2 aqueous dispersion 2 is added with 0.3 g of epoxy compound Denacol EX-810 (manufactured by Nagase ChemteX Corp.) and 75 g of water. The coating liquid was applied using a bar coater so that the dry film thickness was 0.1 μm, and dried at 80 ° C. for 10 minutes to obtain a laminated film 2. The evaluation results of the laminated film 2 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 2 and the laminated film in which the laminated film 2 was left in a dryer at 80 ° C. for 1 week were used as a roll laminator using the adhesive produced in Production Example 5. The polarizing plate 2 was obtained by bonding together. The measurement results of the peel strength of the polarizing plate 2 are shown in Table 1.

( Example 2 )
Sodium hydroxide, which is a neutralizing agent for the aqueous dispersion containing the post-neutralization water-based urethane resin 1 prepared in the reference example, was replaced with γ -aminopropyltriethoxysilane (boiling point: 217 ° C., blending amount: 58.4 g). An aqueous dispersion of an aqueous urethane resin 3 after neutralization treatment having a solid content of 41% was obtained by the same operation as in the reference example except that the water dispersion was changed to.

  Next, using a corona treatment apparatus (Kasuga Denki Co., Ltd.), the base film (I) subjected to the discharge treatment under the conditions of an output of 300 W, an electrode length of 240 mm, a work electrode distance of 3.0 mm, and a conveying speed of 4 m / min. On the surface, 5.0 g of aqueous dispersion 3 of aqueous urethane resin 3 after neutralization treatment, 0.2 g of Duranate WB40-100 (manufactured by Asahi Kasei Chemicals Co., Ltd.) which is an aqueous isocyanate compound, and Snowtex ZL which is silica particles (Nissan Chemical Co., Ltd.) 0.5 g and 75 g of water are added to the coating solution using a bar coater so that the dry film thickness is 0.2 μm, and dried at 80 ° C. for 10 minutes. Thus, a laminated film 3 was obtained. The evaluation results of the laminated film 3 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 3, and the laminated film in which the laminated film 3 was allowed to stand for 1 week in a dryer at 80 ° C. were used for the roll laminator using the adhesive produced in Production Example 5. The polarizing plate 3 was obtained by bonding together. Table 1 shows the measurement results of the peel strength of the polarizing plate 3.

( Example 3 )
In a 2000 ml four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condenser tube, 200 g of 5-norbornene-2,3-dimethanol, 613 g of 1,6-hexanediol, 376 g of azelaic acid, 642 g of diphenyl carbonate ( The mixture consisting of ester group and carbonate group molar ratio: 57/43) and hydroquinone monomethyl ether 0.6 g was heated, and phenol and water were distilled off from the reaction system at 160 ° C. When the acid value became 0.3 mgKOH / g or less, a vacuum was applied to proceed further condensation to obtain a polyester polycarbonate diol having a hydroxyl value of 56 mgKOH / g. Next, in a 2000 ml four-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, and a cooling tube, 840 g of the previously prepared polyester carbonate diol, 119 g of tolylene diisocyanate, and 200 g of methyl ethyl ketone were added, and 75 ° C. while introducing nitrogen. For 1 hour. After completion of the reaction, the mixture was cooled to 60 ° C., 35.6 g of dimethylolpropionic acid was added, and the mixture was reacted at 75 ° C. to obtain an acid structure-containing aqueous urethane resin solution having an NCO of 0.5%. Next, this acid structure-containing water-based urethane resin was cooled to 40 ° C., 1500 g of water and 15.9 g of ethylenediamine (boiling point: 117 ° C.) were added, and emulsification was carried out by stirring at high speed with a homomixer. Methyl ethyl ketone was distilled off from this emulsion under heating and reduced pressure, and an aqueous dispersion of an aqueous urethane resin 4 was obtained after neutralization with a solid content of 40%.

  Next, using a remote atmospheric pressure plasma processing apparatus (manufactured by E-Square Co., Ltd.), a substrate film (surface treatment was performed under conditions of an output of 1.2 kW, a nitrogen flow rate of 200 L / min, and a conveyance speed of 1 m / min) II) on the surface of the aqueous dispersion 4 of water-based urethane resin 4 after neutralization treatment, methylated melamine resin MW-30 (manufactured by Sanwa Chemical Co., Ltd.) 0.1 g of water-based amino compound, and water 75 g Was applied using a bar coater so that the dry film thickness was 0.1 μm, and dried at 80 ° C. for 10 minutes to obtain a laminated film 4. The evaluation results of the laminated film 4 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 4, and the laminated film in which the laminated film 4 was allowed to stand for 1 week in a dryer at 80 ° C. were used for the roll laminator using the adhesive produced in Production Example 5. Then, the polarizing plate 4 was obtained. Table 1 shows the measurement results of the peel strength of the polarizing plate 4.

( Example 4 )
In a 2000 ml four-necked flask equipped with a thermometer, stirrer, nitrogen introduction tube, and cooling tube, 840 g of polyether polyol, Exenol 2020 (manufactured by Asahi Glass Co., Ltd., hydroxyl value 56 mg KOH / g), 119 g of tolylene diisocyanate, methyl ethyl ketone 200 g was allowed to react at 75 ° C. for 1 hour while introducing nitrogen. After completion of the reaction, the mixture was cooled to 60 ° C., 35.6 g of dimethylolpropionic acid was added, and the mixture was reacted at 75 ° C. to obtain an acid structure-containing aqueous urethane resin solution having a terminal isocyanate group of 0.5% NCO. . Next, this acid structure-containing water-based urethane resin is cooled to 40 ° C., and 1500 g of water, 3.3 g of monoethanolamine (boiling point: 171 ° C.), and 21.3 g of triethylamine (boiling point: 89 ° C.) are added, and high speed is obtained with a homomixer. Emulsification was performed by stirring. Methyl ethyl ketone was distilled off from this emulsion under heating and reduced pressure to obtain an aqueous dispersion of an aqueous urethane resin 5 after neutralization with a solid content of 40%. The aqueous urethane resin 5 is a resin in which 20.4% of the acid structure in the resin is neutralized with monoethanolamine.

  Next, 5.0 g of the aqueous dispersion 5 of the aqueous urethane resin 5 after the neutralization treatment is applied to the surface of the base film (III) whose surface has been modified by immersing it in a 5% by weight sodium hydroxide aqueous solution for 30 minutes, Using a bar coater, a water-based urethane resin coating solution in which 75 g of water is added to 0.1 g of Carbodilite V-02 (Nisshinbo Co., Ltd.), which is a carbodiimide compound, so that the dry film thickness is 0.2 μm. The laminated film 5 was obtained by applying and drying at 80 ° C. for 10 minutes. The evaluation results of the laminated film 5 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 5, and the laminated film in which the laminated film 5 was allowed to stand for 1 week in a dryer at 80 ° C. were used for the roll laminator using the adhesive produced in Production Example 5. The polarizing plate 5 was obtained by bonding together. Table 1 shows the measurement results of the peel strength of the polarizing plate 5.

(Comparative Example 1)
The same operation as in the Reference Example , except that sodium hydroxide, which is a neutralizing agent for neutralizing the acid-containing aqueous urethane resin prepared in the Reference Example , was changed to triethylamine (boiling point: 89 ° C., blending amount: 26.7 g). As a result, an aqueous dispersion of the comparative aqueous urethane resin 1 having a solid content of 40% was obtained.

  Next, using a corona treatment apparatus (Kasuga Denki Co., Ltd.), the base film (I) subjected to the discharge treatment under the conditions of an output of 300 W, an electrode length of 240 mm, a work electrode distance of 3.0 mm, and a conveying speed of 4 m / min. The coating is made by adding 0.3 g of an epoxy compound, Denacol EX-810 (manufactured by Nagase ChemteX Corp.) and 75 g of water to 5.0 g of the aqueous dispersion 1 of the aqueous urethane resin 1 for comparative example. The working solution was applied using a bar coater so that the dry film thickness was 0.1 μm, and dried at 80 ° C. for 10 minutes to obtain a laminated film 1 for comparative example. The evaluation results of the comparative example product layer film 1 are shown in Table 1.

  Next, the polarizer produced in Production Example 4, the laminated film 1 for Comparative Example, and the laminated film 1 in which the laminated film 1 for Comparative Example was allowed to stand for 1 week in a dryer at 80 ° C. were produced in Production Example 5. The polarizing plate 1 for comparative examples was obtained by sticking together with a roll laminator using the agent. Table 1 shows the measurement results of the peel strength of the polarizing plate 1 for comparative example.

Claims (5)

On the surface of the film layer of the base film having an alicyclic structure-containing polymer film layer or a (meth) acrylic resin film layer on at least one outermost surface thereof,
An aqueous dispersion containing an aqueous urethane resin obtained by neutralizing at least part of the acid structure contained in the acid structure-containing aqueous urethane resin with a nonvolatile base that is an organic base having a boiling point of 100 ° C. or higher ,
The manufacturing method of the laminated film characterized by including the process of apply | coating and forming the urethane resin layer of thickness 0.03-0.2 micrometer .   The method for producing a laminated film according to claim 1, wherein 20% or more of the acid structure in the acid structure-containing water-based urethane resin is neutralized by a non-volatile base.   The method for producing a laminated film according to claim 1, wherein the acid structure-containing water-based urethane resin is a self-emulsifying water-based urethane resin.   The said aqueous dispersion contains a crosslinking agent, The manufacturing method of the laminated | multilayer film as described in any one of Claims 1-3 characterized by the above-mentioned.   The laminated film manufactured by the manufacturing method of the laminated film as described in any one of Claims 1-4.