JP2006047741A - Polarizing plate, polarizing plate manufacturing method and display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate capable of remarkably reducing light leakage in the periphery even in the case of a large screen TV, to provide a method for manufacturing the polarizing plate, and to provide a display apparatus using the polarizing plate. <P>SOLUTION: Regarding the polarizing plate having a polarizing plate protecting film, a polarizer, a phase difference film and an adhesion layer, the polarizing plate is provided with the adhesion layer whose storage modulus of elasticity is varied in a plane of one polarizing plate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polarizing plate, a manufacturing method of the polarizing plate, and a display device, and more particularly to a polarizing plate in which peripheral light leakage is significantly reduced even in a large screen TV, a manufacturing method of the polarizing plate, and a display device using the same. .

  A liquid crystal image display device can be directly connected to an IC circuit with a low voltage and low power consumption, and can be reduced in thickness, and thus is widely used as a display device for a word processor, a personal computer, or the like. The basic configuration of this liquid crystal image display device is one in which a polarizing plate is provided on one side or both sides of a liquid crystal cell. Since a polarizing plate allows only light of a polarization plane in a certain direction to pass, in a liquid crystal image display device, the polarizing plate plays an important role in visualizing changes in alignment due to an electric field. The performance of the image display device is greatly affected.

  The general structure of the polarizing plate is, for example, a protective film made of cellulose ester film such as cellulose triacetate film or cellulose acetate propionate film on one or both sides of a polarizer made of uniaxially stretched and iodine-stained polyvinyl alcohol film. Alternatively, the retardation film is bonded through an adhesive such as polyvinyl alcohol. Further, the polarizing plate is bonded to the liquid crystal cell through an adhesive layer.

  However, it is known that when the polarizing plate is left in an environment of high temperature and high humidity, the dimensions change. However, when a dimensional change occurs in the polarizing plate fixed to the liquid crystal cell with the adhesive, there is a problem between the adhesive layer and the polarizing plate. As a result, an unnecessary phase difference is generated in the polarizing plate. As a result, when the liquid crystal display device displays black, light leaks from the periphery of the screen and appears white. May be. In addition, since the cellulose ester film itself undergoes a dimensional change in a high temperature and high humidity environment, there is a problem that the light leakage failure is promoted. In particular, when the liquid crystal display has a large screen, a light leakage failure due to a dimensional change of each part of the polarizing plate is more likely to occur, which is a problem.

  In response to the above problems, MD is the stretch rate (%) in the web conveyance direction, and TD is the stretch rate (%) in the width direction, in the stage between the web peeling from the support and the winding. A method for producing a cellulose ester film that satisfies the relationship of 4% ≦ MD−TD ≦ 4% has been proposed (see, for example, Patent Document 1). On the other hand, for the purpose of improving the dimensional stability of the cellulose ester film, a cellulose ester film is proposed in which the total plasticizer content relative to the cellulose ester and the ratio of the plasticizer with a freezing point of 20 ° C. or less to the cellulose ester are set to specific conditions. (For example, see Patent Document 2). In addition, a liquid crystal display member that includes a phthalate ester plasticizer in a specific range with respect to cellulose ester and has improved dimensional stability has been proposed (for example, see Patent Document 3). Furthermore, it contains at least one plasticizer having a freezing point of 25 ° C. or more and a plasticizer having a freezing point of less than 25 ° C., and an ultraviolet absorber having a melting point of less than 20 ° C. And the cellulose-ester film which improved the durability of a polarizing plate is proposed (for example, refer patent document 4).

  However, as described above, the demand for thinner, wider, and higher quality protective films for liquid crystal polarizing plates has become stronger as liquid crystal displays have become thinner and lighter, larger screens, and higher definition. In order to meet such demands, the methods proposed in the above-mentioned patent documents have some effects, but further improvements are required.

On the other hand, the technique regarding the usage method of the adhesive at the time of bonding a polarizing plate to a liquid crystal cell is also disclosed (for example, refer patent document 5, 6). Both are described to select the pressure-sensitive adhesive having the optimal storage elastic modulus from the viewpoint of reworkability and stress relaxation, focusing on the elasticity of the pressure-sensitive adhesive.
According to the inventor's study, a certain degree of effect is recognized for frame-like light leakage failure, etc., but particularly when a large polarizing plate exceeding 30 cm × 40 cm is used. The design by optimizing the adhesive strength is not enough, and when the number of backlights used is increased to improve the brightness of the panel or when a direct type backlight is used, the influence of heat from the back of the panel is affected. It has become even larger, and it has been found that new means of improvement are required.
JP 2003-94470 A Japanese Patent Laid-Open No. 10-120824 JP 10-152568 A JP 2001-151901 A Japanese Patent Laid-Open No. 2002-249752 JP 2003-139552 A

  An object of the present invention is to provide a polarizing plate, a method for manufacturing the polarizing plate, and a display device using the polarizing plate, in which peripheral light leakage is remarkably reduced even in a large screen TV.

  The above object of the present invention is achieved by the following configurations.

(Claim 1)
A polarizing plate having a polarizing plate protective film, a polarizer, a retardation film, and an adhesive layer, wherein the polarizing plate has an adhesive layer having a different storage elastic modulus within the plane of one polarizing plate.

(Claim 2)
The polarizing plate according to claim 1, further comprising an adhesive layer in which a storage elastic modulus of an edge portion of the polarizing plate is lower than a storage elastic modulus in the vicinity of a central portion.

(Claim 3)
The polarizing plate according to claim 1, further comprising an adhesive layer having a storage elastic modulus of the edge portion of 80% or less with respect to a storage elastic modulus in the vicinity of the center portion.

(Claim 4)
The polarizing plate according to claim 1, wherein the retardation film contains a cyclic olefin resin or a cellulose derivative.

(Claim 5)
A method for producing a polarizing plate, comprising: adhering a component constituting at least one adhesive layer to an adhesive layer forming surface to form an adhesive layer having different adhesiveness in one polarizing plate.

(Claim 6)
Production of a polarizing plate characterized by forming a pressure-sensitive adhesive layer having different adhesive properties in a single polarizing plate by adhering droplets containing at least one type of pressure-sensitive adhesive layer to an adhesive layer-forming surface Method.

(Claim 7)
The method for producing a polarizing plate according to claim 6, wherein the means for attaching the droplets to the adhesive layer forming surface is an inkjet method.

(Claim 8)
A polarizing plate having a polarizing plate protective film, a polarizer, a retardation film, an adhesive layer between the polarizer of the polarizing plate and a liquid crystal cell, and a storage elastic modulus of the adhesive layer of one sheet A display device characterized by being different in the plane.

(Claim 9)
The display device according to claim 8, wherein the adhesive layer is an adhesive layer in which a storage elastic modulus of an edge portion is lower than that in a vicinity of a central portion.

  According to the present invention, it is possible to provide a polarizing plate in which peripheral light leakage is remarkably reduced even in a large screen TV, a manufacturing method of the polarizing plate, and a display device using the polarizing plate.

  The best mode for carrying out the present invention will be described in detail below, but the present invention is not limited thereto.

  The polarizing plate of the present invention is characterized in that, in a polarizing plate having a polarizing plate protective film, a polarizer, a retardation film, and an adhesive layer, the adhesive layer has a different storage elastic modulus in the plane of one polarizing plate. To do. Furthermore, it has an adhesive layer in which the storage elastic modulus of the edge portion of the polarizing plate is lower than the storage elastic modulus near the center.

  When a pressure-sensitive adhesive layer having a constant adhesive strength or storage elastic modulus is provided in the plane of a single polarizing plate and is fixed to the liquid crystal cell as in the past, when the dimensional change occurs in the polarizing plate fixed to the liquid crystal cell, the pressure-sensitive adhesive layer As a result, stress is generated between the polarizing plate and an unnecessary phase difference is generated in the polarizing plate. Therefore, when the liquid crystal display device displays black, light leaks from the periphery of the screen and appears white. It may cause a failure. The reason why the light leakage becomes a frame shape is that the stress is more likely to occur at the edge portion than at the center portion of the polarizing plate.

  In this case, if the entire surface is made of a soft adhesive layer, it is convenient for stress relaxation, but there is a problem in that the adhesiveness is insufficient and axial misalignment is likely to occur. On the other hand, stress relaxation is insufficient with a hard adhesive layer. In particular, when a large polarizing plate exceeding 30 cm × 40 cm is used, the conventional design by optimizing the adhesive force is not sufficient.

  As a result of intensive studies in view of the above problems, the present inventor can effectively disperse the stress on the polarizing plate by having an adhesive layer having a different storage elastic modulus within the plane of one polarizing plate, which is unnecessary. It is as soon as the present invention has been found that the expression of phase difference can be controlled. In particular, it is preferable to have an adhesive layer in which the storage elastic modulus of the edge portion of the polarizing plate is lower than the storage elastic modulus near the center.

  Hereinafter, the present invention will be described in detail for each element.

(Adhesive, adhesive layer)
As the pressure-sensitive adhesive used in the present invention, a pressure-sensitive adhesive having a storage elastic modulus at 25 ° C. of 1.0 × 10 ⁴ Pa to 1.0 × 10 ⁹ Pa in at least a part of the pressure-sensitive adhesive layer is used. Although not limited, a curable pressure-sensitive adhesive that forms a high molecular weight body or a crosslinked structure by various chemical reactions after applying and bonding the pressure-sensitive adhesive is suitably used. Specific examples include, for example, urethane adhesives, epoxy adhesives, aqueous polymer-isocyanate adhesives, curable adhesives such as thermosetting acrylic adhesives, moisture-curing urethane adhesives, polyether methacrylate types, Examples include anaerobic pressure-sensitive adhesives such as ester-based methacrylate type and oxidized polyether methacrylate, cyanoacrylate-based instantaneous pressure-sensitive adhesives, and acrylate-peroxide-based two-component instantaneous pressure-sensitive adhesives.

  The pressure-sensitive adhesive may be a one-component type or a type that is used by mixing two or more components before use. The pressure-sensitive adhesive may be a solvent system using an organic solvent as a medium, or an aqueous system such as an emulsion type, a colloidal dispersion type, or an aqueous solution type that is a medium containing water as a main component. It may be a solvent type. The concentration of the pressure-sensitive adhesive liquid may be appropriately determined depending on the film thickness after adhesion, a coating machine, coating conditions, and the like, and is usually 0.1 to 50% by mass.

In the present invention, the storage elastic modulus at 25 ° C. of the pressure-sensitive adhesive in the central part of the polarizing plate is preferably 1.0 × 10 ⁴ Pa to 1.0 × 10 ⁹ Pa, more preferably 1.0 × 10 ⁵ to 1.0 × 10 ⁹ Pa. When the elastic modulus of the pressure-sensitive adhesive is less than 1.0 × 10 ⁴ Pa, sufficient adhesive strength cannot be obtained, peeling occurs when the axial displacement or heat test is performed, and the elastic modulus is 1.0 ×. If it exceeds 10 ⁹ Pa, the pressure-sensitive adhesive is too hard, which causes a problem that cracks and chips are generated during punching.

  The storage elastic modulus at 25 ° C. of the pressure-sensitive adhesive is a value obtained by dynamic viscoelasticity measurement, specifically, a value measured by the method described in the storage elastic modulus measurement method described later. The thickness of the adhesive layer after curing is preferably 0.005 to 50 μm, more preferably 0.01 to 10 μm. If the thickness is less than 0.005 μm, sufficient adhesive strength cannot be obtained, and if it exceeds 50 μm, fading of the polarizing plate may occur during the moisture resistance test. As the film thickness of the adhesive layer, the film thickness may be different at a part having different adhesive force, but the part having a different adhesive force is preferably the same film thickness.

  In the present invention, in order to achieve both the stability of the optical axis of the polarizing plate with respect to the liquid crystal cell and the aim of dispersing the stress, the storage elastic modulus of the edge portion is 80% or less with respect to the storage elastic modulus near the center. It is preferable to have an adhesive layer.

  That is, when the high storage elastic modulus in the vicinity of the central part is 100%, the elastic modulus of the peripheral part is preferably 80% or less, more preferably 0.01 to 80% or less, More preferably, it is 70% or less. In particular, it is preferably 1 to 60% or less.

  In this case, after applying a soft adhesive uniformly, you may make the component which makes this adhesive hard in the center vicinity. Or after applying a hard adhesive uniformly, you may adhere the component or soft adhesive which softens this adhesive to a peripheral part.

  Further, a post-curing pressure-sensitive adhesive may be used as the pressure-sensitive adhesive to be used. For example, the pressure-sensitive adhesive layer at the center of the polarizing plate can be made harder than the periphery by post-curing. The means for post-curing is not particularly limited, but it is preferable to use heat, light or the like.

  The method for forming the pressure-sensitive adhesive layer is not particularly limited and includes general methods such as a method of applying a pressure-sensitive adhesive solution by a method such as a gravure coater, a micro gravure coater, a comma coater, a bar coater, a spray coating, an ink jet method, or the like. It is done. In the present invention, it is preferable to provide a pressure-sensitive adhesive layer having different storage elastic modulus in the surface by attaching droplets containing at least one type of pressure-sensitive adhesive layer to the pressure-sensitive adhesive layer forming surface, and particularly preferably spray coating or The ink jet method is used.

  The formation pattern of the adhesive layer is preferably changed so that the change in the elastic modulus of the adhesive layer in one polarizing plate decreases stepwise or continuously from the center toward the periphery. A preferable amount of change in elastic modulus is 1 to 50% / cm. This is preferable because the unevenness caused by the pattern when the screen is observed is not noticeable.

  FIG. 1 is a schematic view showing various patterns of an adhesive layer according to the present invention.

  In the present invention, two or more types of different pressure-sensitive adhesives can be printed with a pattern as shown in FIG. In FIG. 1, A is a site | part with the highest storage elastic modulus, and BF is a site | part whose storage elastic modulus is 80% or less of A preferably. It is preferable to make the storage elastic modulus lower as the outer circumference is reached.

  FIG. 2 is a cross-sectional view showing an example of an inkjet head that can be used in the inkjet method used in the present invention.

  2A is a cross-sectional view of the inkjet head, and FIG. 2B is an enlarged view taken along the line AA in FIG. 2A. In the figure, 11 is a substrate, 12 is a piezoelectric element, 13 is a flow path plate, 13a is an ink flow path, 13b is a wall, 14 is a common liquid chamber constituent member, 14a is a common liquid chamber, 15 is an ink supply pipe, 16 Is a nozzle plate, 16a is a nozzle, 17 is a drive circuit printed board (PCB), 18 is a lead portion, 19 is a drive electrode, 20 is a groove, 21 is a protective plate, 22 is a fluid resistance, 23 and 24 are electrodes, 25 Is an upper partition wall, 26 is a heater, 27 is a heater power supply, 28 is a heat transfer member, and 10 is an inkjet head.

  In the integrated inkjet head 10, the laminated piezoelectric element 12 having the electrodes 23 and 24 is grooved in the direction of the flow path 13a corresponding to the flow path 13a, so that the groove 20 and the driving piezoelectric element 12b. And non-driving piezoelectric element 12a. The groove 20 is filled with a filler. The flow path plate 13 is joined to the piezoelectric element 12 subjected to the groove processing through the upper partition wall 25. In other words, the upper partition 25 is supported by the non-driving piezoelectric element 12a and the wall 13b that separates the adjacent flow path. The width of the driving piezoelectric element 12b is slightly narrower than the width of the flow path 13a. When the driving piezoelectric element 12b selected by the driving circuit on the driving circuit printed board (PCB) is applied with a pulsed signal voltage, the driving piezoelectric element 12b. The element 12b changes in the thickness direction, and the volume of the flow path 13a changes via the upper partition wall 25. As a result, ink droplets are ejected from the nozzles 16a of the nozzle plate 16.

  Heaters 26 are bonded to the flow path plate 13 via heat transfer members 28, respectively. The heat transfer member 28 is provided around the nozzle surface. The heat transfer member 28 is intended to efficiently transfer the heat from the heater 26 to the flow path plate 13, carry the heat from the heater 26 to the vicinity of the nozzle surface, and warm the air in the vicinity of the nozzle surface. A material with good conductivity is used. For example, metals such as aluminum, iron, nickel, copper, and stainless steel, or ceramics such as SiC, BeO, and AlN are preferable materials.

  When the piezoelectric element is driven, the piezoelectric element is displaced in a direction perpendicular to the longitudinal direction of the flow path, and the volume of the flow path is changed. By the change in volume, ink droplets are ejected from the nozzle. The piezoelectric element is given a signal that keeps the flow path volume constantly reduced, and after the displacement of the selected flow path in the direction of increasing the flow volume, the displacement that reduces the flow volume again is applied. By applying a pulse signal to be applied, ink is ejected as ink droplets from a nozzle corresponding to the flow path.

  FIG. 3 is a schematic view showing an example of an inkjet head unit and a nozzle plate that can be used in the present invention.

  3, (a) of FIG. 3 is a sectional view of the head portion, and (b) of FIG. 3 is a plan view of the nozzle plate. In the figure, 1 is a polarizing plate, 31 is an ink droplet, and 32 is a nozzle. The ink droplet 31 ejected from the nozzle 32 flies in the direction of the polarizing plate 1 and adheres. The ink droplets landed on the polarizing plate 1 are layered.

  In the present invention, as shown in FIG. 3 (b), the nozzles of the inkjet head unit are preferably arranged in a staggered manner, and provided in multiple stages in parallel in the transport direction of the polarizing plate 1, This is a preferred embodiment because adhesive layers having different storage elastic moduli can be provided in any shape and in any place. Further, the air flow is controlled so that the ink droplet 31 emitted by the ink jet method is not disturbed and biased by the air around the polarizing plate 1 moving, or unintentionally uneven.

  The ink jet head is not limited to the above, and the electrostatic discharge type ink jet head described in JP-A-2004-58505 can also be used for the adhesive layer processing of the present invention. The ink jet patterning apparatus described in Japanese Patent Application Laid-Open No. 2004-54271 can be diverted to the adhesive layer processing of the present invention, the jet head described in Japanese Patent Application Laid-Open No. 2004-55520 can also be used, and the ink jet head described in Japanese Patent No. 3,5000,636 Can be diverted, and the ink jet recording system described in Registration No. 3,501,583 can also be diverted to the adhesive layer processing of the present invention.

  Further, it is preferable to check whether or not the head is clogged by performing a test discharge before discharging the ink for forming the layer. When the clogging is confirmed or at the start of production, the head cleaning is performed. It is preferable to implement. The head cleaning may be performed with the ink used or with a cleaning liquid mainly composed of a solvent. A solvent that can be used for the ink is preferably used as the solvent of the cleaning liquid. If necessary, a surfactant (nonionic, fluorine, silicon, etc.) may be contained in an amount of about 0.01 to 1%.

  It is preferable to appropriately adjust the ink discharge density for forming the layer.

  When clogging of a head is detected during production, it is preferable to stop supplying ink to the head. It is also preferable to increase the amount of ink ejected from other heads so that unevenness does not occur in the formed layer. When using a multi-stage inkjet head, it is preferable to clean the clogged inkjet head while continuing production. In that case, the ink is discharged so that the cleaning liquid does not adhere to the substrate film to be treated. It is preferable to change the direction or to discharge toward another member that receives the cleaning liquid. During head cleaning, it is preferable to increase the amount of ink discharged from another inkjet head or to continue production using a spare inkjet head.

  In addition, when any abnormality such as clogging of the head is confirmed during production, it is preferable to mark the end portion of the film substrate with an ink jet. The marking is preferably performed with colored ink, and it becomes easy to remove the part from the product later by clarifying the abnormal part. The pressure-sensitive adhesive layer may be formed continuously on a long film or a polarizing plate by an ink jet method or may be formed for each cut polarizing plate.

(Base material)
The polarizing plate protective film and retardation film having a hard coat layer of the present invention are preferably the following transparent plastic substrates.

  As the transparent plastic substrate used in the present invention, it is mentioned that the production is easy, the adhesiveness with the hard coat layer is good, the optical transparency is preferable, etc. Is preferably used.

  The term “transparent” as used in the present invention means that the visible light transmittance is 60% or more, preferably 80% or more, and particularly preferably 90% or more.

  Although it will not specifically limit if it has said property, For example, a cellulose-ester type film, a polyester-type film, a polycarbonate-type film, a polyarylate-type film, a polysulfone (a polyether sulfone is also included) type film, a polyethylene terephthalate, polyethylene Polyester film such as naphthalate, polyethylene film, polypropylene film, cellophane, cellulose diacetate film, cellulose triacetate, cellulose acetate butyrate film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, Polycarbonate film, cyclic olefin resin film (Arton (manufactured by JSR), Zeo) , ZEONOR (manufactured by Nippon Zeon Co., Ltd.), polymethylpentene film, polyetherketone film, polyetherketoneimide film, polyimide film, polyamide film, fluororesin film, nylon film, polymethylmethacrylate film, acrylic film or A glass plate etc. can be mentioned. Among them, as the polarizing plate protective film and the retardation film, a cellulose ester film, a polycarbonate film, a polysulfone (including polyether sulfone) and a cyclic olefin resin film are preferable. In the present invention, the polarizing plate protective film is particularly a cellulose ester. Films (for example, Konica Minoltac product names KC8UX2MW, KC4UX2MW, KC5UX, KC8UY, KC4UY, KC5UN, KC12UR (manufactured by Konica Minolta Opto Co., Ltd.)) are manufactured, cost, transparency, isotropic, adhesiveness, etc. From the viewpoint of, it is preferably used.

  The retardation film is preferably a cyclic olefin resin film or a cellulose ester film. These films may be films produced by melt casting film formation or films produced by solution casting film formation.

The optical properties of the substrate film thickness direction retardation R _t is -100Nm～400nm, retardation R ₀ in the plane direction those 0nm~1000nm is preferably used.

(Cellulose ester film)
First, the cellulose ester film preferably used in the present invention will be described.

  The cellulose ester preferably used in the present invention is a cellulose ester of an aliphatic carboxylic acid or aromatic carboxylic acid having 2 to 22 carbon atoms, particularly cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cellulose acetate phthalate. Is preferably used.

  In particular, when the substitution degree of the acetyl group is X and the substitution degree of the acyl group having 3 to 22 carbon atoms is Y, a base film having a mixed acid ester of cellulose in which X and Y are in the following ranges is preferably used.

2.3 ≦ X + Y ≦ 3.0
0.1 ≦ Y ≦ 1.2
In particular, 2.5 ≦ X + Y ≦ 2.85
It is preferable that 0.3 ≦ Y ≦ 1.2.

  When cellulose ester is used as the base film according to the present invention, the cellulose used as a raw material for the cellulose ester is not particularly limited, and examples thereof include cotton linter, wood pulp (derived from coniferous tree, derived from broadleaf tree), kenaf and the like. . Moreover, the cellulose ester obtained from them can be mixed and used in arbitrary ratios, respectively. When the acylating agent is an acid anhydride (acetic anhydride, propionic anhydride, butyric anhydride), these cellulose esters use an organic solvent such as acetic acid or an organic solvent such as methylene chloride, and It can be obtained by reacting with a cellulose raw material using a protic catalyst.

When the acylating agent is acid chloride (CH ₃ COCl, C ₂ H ₅ COCl, C ₃ H ₇ COCl), the reaction is carried out using a basic compound such as an amine as a catalyst. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804. In addition, the cellulose ester used in the present invention is obtained by mixing and reacting the amount of the acylating agent in accordance with the degree of substitution. In the cellulose ester, these acylating agents react with hydroxyl groups of cellulose molecules. Cellulose molecules are composed of many glucose units linked together, and the glucose unit has three hydroxyl groups. The number of acyl groups derived from these three hydroxyl groups is called the degree of substitution (mol%). For example, cellulose triacetate has acetyl groups bonded to all three hydroxyl groups of the glucose unit (actually 2.6 to 3.0).

  The cellulose ester used in the present invention is a mixed fatty acid ester of cellulose in which a propionate group or a butyrate group is bonded in addition to an acetyl group such as cellulose acetate propionate, cellulose acetate butyrate, or cellulose acetate propionate butyrate. Is particularly preferably used. The butyryl group forming butyrate may be linear or branched.

  Cellulose acetate propionate containing a propionate group as a substituent has excellent water resistance and is useful as a film for liquid crystal image display devices.

  The measuring method of the substitution degree of an acyl group can be measured according to the provisions of ASTM-D817-96.

  The number average molecular weight of the cellulose ester is preferably 70000 to 250,000, since it has a high mechanical strength when molded and an appropriate dope viscosity, more preferably 80000 to 200000.

  These cellulose esters are pressurized by applying a cellulose ester solution (dope) generally called a solution casting film forming method onto, for example, an endless metal belt for infinite transport or a support for casting of a rotating metal drum. It is preferable to manufacture the dope from a die by casting (casting).

  The organic solvent used for the preparation of these dopes is preferably capable of dissolving the cellulose ester and having an appropriate boiling point, for example, methylene chloride, methyl acetate, ethyl acetate, amyl acetate, methyl acetoacetate, acetone, tetrahydrofuran 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 1,3-difluoro-2 -Propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3 , 3,3-pentafluoro-1-propanol, nitroethane, 1,3-dimethyl-2-imidazolidinone, etc. It is possible, organic halogen compounds such as methylene chloride, dioxolane derivatives, methyl acetate, ethyl acetate, acetone, methyl acetoacetate, and the like are preferable organic solvents (i.e., good solvent), and as.

  Moreover, as shown in the following film forming process, it is used from the viewpoint of preventing foaming in the web when the solvent is dried from the web (dope film) formed on the casting support in the solvent evaporation process. The boiling point of the organic solvent is preferably 30 to 80 ° C. For example, the good solvent described above has a boiling point of methylene chloride (boiling point 40.4 ° C), methyl acetate (boiling point 56.32 ° C), acetone (boiling point 56.56 ° C). 3 ° C.), ethyl acetate (boiling point 76.82 ° C.) and the like.

  Among the good solvents described above, methylene chloride or methyl acetate, which is excellent in solubility, is preferably used.

  It is preferable to contain 0.1 mass%-40 mass% of C1-C4 alcohol other than the said organic solvent. It is particularly preferable that the alcohol is contained at 5 to 30% by mass. After casting the dope described above onto a casting support, the solvent starts to evaporate and the alcohol ratio increases and the web (dope film) gels, making the web strong and peeling from the casting support. It is also used as a gelling solvent for facilitating the dissolution, and when these ratios are small, it also has a role of promoting the dissolution of the cellulose ester of the non-chlorine organic solvent.

  Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol and the like.

  Of these solvents, ethanol is preferred because it has good dope stability, relatively low boiling point, good drying properties, and no toxicity. It is preferable to use a solvent containing 5% by mass to 30% by mass of ethanol with respect to 70% by mass to 95% by mass of methylene chloride. Methyl acetate can be used in place of methylene chloride. At this time, the dope may be prepared by a cooling dissolution method.

  The cellulose ester film used in the present invention is preferably at least stretched in the width direction, and is 1.01 times to the width direction when the residual solvent amount is 3% by mass to 40% by mass in the solution casting process. The film is preferably stretched 1.5 times. When used as a retardation film, it is more preferably biaxial stretching in the width direction and the longitudinal direction, and when the residual solvent amount is 3% by mass to 40% by mass, respectively in the width direction and the longitudinal direction. It is desirable to be stretched by 1.01 times to 1.5 times. By doing in this way, the retardation film excellent in planarity and retardation performance can be obtained.

  When used as a retardation film, preferable retardation values in the present invention are Rt of 70 to 400 nm, Ro of 30 to 300 nm, and further preferably Ro of 30 to 70 nm.

  The residual solvent amount is represented by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Here, M is the mass of the web (cellulose ester film containing the solvent) at an arbitrary point in time, and N is the mass when the web of M is dried at 110 ° C. for 3 hours.

  Furthermore, by performing biaxial stretching and knurling, it is possible to remarkably improve the deterioration of the winding shape during storage of the long optical film in the form of a roll.

  In the present invention, the biaxially stretched cellulose ester film is preferably a transparent support having a light transmittance of 90% or more, more preferably 93% or more.

The cellulose ester film according to the present invention preferably has a thickness of 10 μm to 100 μm, more preferably 40 μm to 80 μm, and moisture permeability was measured according to JIS Z 0208 (25 ° C., 90% RH). The value is preferably 200 g / m ² · 24 hours or less, more preferably 10 to 180 g / m ² · 24 hours or less, and particularly preferably 160 g / m ² · 24 hours or less. In particular, it is preferable that the film thickness is 10 μm to 80 μm and the moisture permeability is within the above range.

  In the present invention, it is preferable to use a long film, and specifically, a film having a length of about 100 m to 5000 m is shown, which is usually provided in a roll shape. Further, the width of the base film is preferably 1.4 m or more from the viewpoint of productivity. More preferably, it is the range of 1.4-4m.

  When a cellulose ester film is used for the polarizing plate protective film or the retardation film of the present invention, it is preferable to contain the following plasticizer. Examples of plasticizers include phosphate ester plasticizers, phthalate ester plasticizers, trimellitic acid ester plasticizers, pyromellitic acid plasticizers, glycolate plasticizers, citrate ester plasticizers, and polyesters. A plasticizer or the like can be preferably used.

  For phosphate plasticizers, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenylbiphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc. For phthalate ester plasticizers, diethyl phthalate, dimethoxy For trimellitic acid plasticizers such as ethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, butyl benzyl phthalate, diphenyl phthalate, dicyclohexyl phthalate, tributyl trimellitate, triphenyl trimellitate, triethyl For pyromellitic acid ester plasticizers such as trimellitate, tetrabutylpyromellitate, In the case of glycolate plasticizers such as lupyromelitate and tetraethylpyromellitate, triacetin, tributyrin, ethylphthalylethyl glycolate, methylphthalylethyl glycolate, butylphthalylbutyl glycolate, etc. Citrate, tri-n-butyl citrate, acetyl triethyl citrate, acetyl tri-n-butyl citrate, acetyl tri-n- (2-ethylhexyl) citrate and the like can be preferably used. Examples of other carboxylic acid esters include trimethylolpropane tribenzoate, butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic acid esters.

  As the polyester plasticizer, a copolymer of a dibasic acid such as an aliphatic dibasic acid, an alicyclic dibasic acid, or an aromatic dibasic acid and a glycol can be used. The aliphatic dibasic acid is not particularly limited, and adipic acid, sebacic acid, phthalic acid, terephthalic acid, 1,4-cyclohexyl dicarboxylic acid and the like can be used. As the glycol, ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol and the like can be used. These dibasic acids and glycols may be used alone or in combination of two or more.

  The amount of these plasticizers used is preferably 1% by mass to 20% by mass and particularly preferably 3% by mass to 13% by mass with respect to the cellulose ester in terms of film performance, processability and the like.

  For the cellulose ester film of the present invention, an ultraviolet absorber is preferably used.

  As the ultraviolet absorber, those excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less and having little absorption of visible light having a wavelength of 400 nm or more are preferably used from the viewpoint of good liquid crystal display properties.

  Specific examples of the ultraviolet absorber preferably used in the present invention include oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like. However, it is not limited to these.

  Specific examples of the benzotriazole-based ultraviolet absorbers include the following ultraviolet absorbers, but the present invention is not limited thereto.

UV-1: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole UV-2: 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole UV-3 : 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) benzotriazole UV-4: 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl)- 5-Chlorobenzotriazole UV-5: 2- (2'-hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl) benzotriazole UV-6: 2,2-methylenebis (4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol)
UV-7: 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole UV-8: 2- (2H-benzotriazol-2-yl) -6 (Linear and side chain dodecyl) -4-methylphenol (TINUVIN171, manufactured by Ciba)
UV-9: Octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl- 4-Hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (TINUVIN109, manufactured by Ciba)
Moreover, although the following specific example is shown as a benzophenone series ultraviolet absorber, this invention is not limited to these.

UV-10: 2,4-dihydroxybenzophenone UV-11: 2,2'-dihydroxy-4-methoxybenzophenone UV-12: 2-hydroxy-4-methoxy-5-sulfobenzophenone UV-13: Bis (2-methoxy -4-hydroxy-5-benzoylphenylmethane)
As the ultraviolet absorber preferably used in the present invention, a benzotriazole-based ultraviolet absorber and a benzophenone-based ultraviolet absorber that are highly transparent and excellent in preventing the deterioration of the polarizing plate and the liquid crystal are preferable, and unnecessary coloring is less. A benzotriazole-based ultraviolet absorber is particularly preferably used.

  Moreover, the ultraviolet absorber whose distribution coefficient described in Unexamined-Japanese-Patent No. 2001-187825 is 9.2 or more improves the surface quality of a long film, and is excellent also in applicability | paintability. In particular, it is preferable to use an ultraviolet absorber having a distribution coefficient of 10.1 or more.

  Further, the polymer ultraviolet absorbers described in the general formula (1) or general formula (2) described in JP-A-6-148430 and the general formulas (3), (6), and (7) of Japanese Patent Application No. 2000-156039 ( Alternatively, an ultraviolet absorbing polymer) is also preferably used. As a polymer ultraviolet absorber, PUVA-30M (manufactured by Otsuka Chemical Co., Ltd.) and the like are commercially available.

In addition, it is preferable to add inorganic or organic fine particles to the cellulose ester film used in the present invention in order to impart slipperiness and to improve scratch resistance and the like. Examples of inorganic fine particles include silicon oxide, titanium oxide, aluminum oxide, tin oxide, zinc oxide, calcium carbonate, barium sulfate, talc, kaolin, calcium sulfate, and the like, and examples of organic fine particles include polymethacrylic acid. Methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder And polyamide resin powder, polyimide resin powder, and polyfluorinated ethylene resin powder. Of these, silicon oxide fine particles (SiO ₂ fine particles) are preferable.

  The primary average particle diameter of the fine particles added to the cellulose ester film used in the present invention is preferably 20 nm or less, more preferably 5 to 16 nm, and particularly preferably 5 to 12 nm. These fine particles preferably form secondary particles having a particle diameter of 0.1 to 5 μm and are contained in the cellulose ester film, and the preferable average particle diameter is 0.1 to 2 μm, more preferably 0.2 to 0.6 μm. Thereby, the unevenness | corrugation about 0.1-1.0 micrometer high can be formed in the film surface, and, thereby, appropriate slipperiness can be given to the film surface.

  The primary average particle diameter of the fine particles used in the present invention is measured by observing particles with a transmission electron microscope (magnification 500,000 to 2,000,000 times), observing 100 particles, and using the average value, the primary value is measured. The average particle size was taken.

  The apparent specific gravity of the fine particles is preferably 70 g / liter or more, more preferably 90 to 200 g / liter, and particularly preferably 100 to 200 g / liter. A larger apparent specific gravity makes it possible to make a high-concentration dispersion, which improves haze and agglomerates, and is preferable when preparing a dope having a high solid content concentration as in the present invention. Are particularly preferably used.

SiO ₂ fine particles having an average primary particle diameter of 20 nm or less and an apparent specific gravity of 70 g / liter or more are, for example, a mixture of vaporized silicon tetrachloride and hydrogen burned in air at 1000 to 1200 ° C. Can be obtained. For example, it is marketed by the brand name of Aerosil 200V and Aerosil R972V (above, Nippon Aerosil Co., Ltd. product), and can use them.

The apparent specific gravity described above is calculated by the following formula by measuring a weight of SiO ₂ fine particles in a graduated cylinder and measuring the weight at that time.

Apparent specific gravity (g / liter) = SiO ₂ mass (g) / SiO ₂ volume (liter)
Examples of the method for preparing the fine particle dispersion used in the present invention include the following three types.

<< Preparation Method A >>
After stirring and mixing the solvent and fine particles, dispersion is performed with a disperser. This is a fine particle dispersion. The fine particle dispersion is added to the dope solution and stirred.

<< Preparation Method B >>
After stirring and mixing the solvent and fine particles, dispersion is performed with a disperser. This is a fine particle dispersion. Separately, a small amount of cellulose triacetate is added to the solvent and dissolved by stirring. The fine particle dispersion is added to this and stirred. This is a fine particle addition solution. The fine particle additive solution is sufficiently mixed with the dope solution using an in-line mixer.

<< Preparation Method C >>
Add a small amount of cellulose triacetate to the solvent and dissolve with stirring. Fine particles are added to this and dispersed by a disperser. This is a fine particle addition solution. The fine particle additive solution is sufficiently mixed with the dope solution using an in-line mixer.

Preparation method A is excellent in the dispersibility of SiO ₂ fine particles, and preparation method C is excellent in that the SiO ₂ fine particles are difficult to re-aggregate. Among them, the preparation method B described above is a dispersion of SiO ₂ particles, a preferred preparation method SiO ₂ particles have excellent reagglomeration hardly like, both.

《Distribution method》
The concentration of SiO ₂ when the SiO ₂ fine particles are mixed with a solvent and dispersed is preferably 5 to 30% by mass, more preferably 10 to 25% by mass, and most preferably 15 to 20% by mass. A higher dispersion concentration is preferable because liquid turbidity with respect to the added amount tends to be low, and haze and aggregates are improved.

  The solvent used is preferably lower alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol and the like. Although it does not specifically limit as solvents other than a lower alcohol, It is preferable to use the solvent used at the time of film forming of a cellulose ester.

The addition amount of SiO ₂ fine particles to the cellulose ester relative to 100 parts by weight of cellulose ester, SiO ₂ fine particles is preferably 5.0 parts by 0.01 parts by weight, 0.05 parts by weight to 1.0 parts by weight is more Preferably, 0.1 mass part-0.5 mass part is the most preferable. The larger the added amount, the better the dynamic friction coefficient, and the smaller the added amount, the less aggregates.

As the disperser, a normal disperser can be used. Dispersers can be broadly divided into media dispersers and medialess dispersers. For dispersion of SiO ₂ fine particles, a medialess disperser is preferred because of low haze. Examples of the media disperser include a ball mill, a sand mill, and a dyno mill. Examples of the medialess disperser include an ultrasonic type, a centrifugal type, and a high pressure type. In the present invention, a high pressure disperser is preferable. The high pressure dispersion device is a device that creates special conditions such as high shear and high pressure by passing a composition in which fine particles and a solvent are mixed at high speed through a narrow tube. When processing with a high-pressure dispersion apparatus, for example, the maximum pressure condition inside the apparatus is preferably 9.807 MPa or more in a thin tube having a tube diameter of 1 to 2000 μm. More preferably, it is 19.613 MPa or more. Further, at that time, those having a maximum reaching speed of 100 m / second or more and those having a heat transfer speed of 420 kJ / hour or more are preferable.

  Examples of the high-pressure dispersing apparatus include an ultra-high pressure homogenizer (trade name: Microfluidizer) manufactured by Microfluidics Corporation or a nanomizer manufactured by Nanomizer, and other manton gorin type high-pressure dispersing apparatuses such as homogenizer manufactured by Izumi Food Machinery. And UHN-01 manufactured by Sanwa Machinery Co., Ltd.

  In addition, casting a dope containing fine particles so as to be in direct contact with the casting support is preferable because a film having high slip properties and low haze can be obtained.

  It is also preferable that a reactive metal compound or a hydrolyzate thereof is added to the dope composition of the cellulose ester film so that metal oxide fine particles are contained in the film. Preferred examples of the reactive metal compound include metal alkoxides such as Si, Al, Ti, and Zr.

  The cellulose ester film used in the present invention may have a multilayer structure by a co-casting method using a plurality of dopes.

  Co-casting is a sequential multilayer casting method in which two or three layers are configured through different dies, and a simultaneous multilayer casting method in which two or three slits are combined in a die having two or three slits. Any of the multilayer casting methods combining sequential multilayer casting and simultaneous multilayer casting may be used.

  In addition, the cellulose ester used in the present invention is preferably used as a support having a small amount of bright spot foreign matter when formed into a film. In the present invention, the bright spot foreign material is a structure in which two polarizing plates are arranged orthogonally (crossed Nicols), a cellulose ester film is arranged between them, and light from a light source is applied from one side to the other side. When the cellulose ester film is observed, the light from the light source appears to leak.

  At this time, the polarizing plate used for the evaluation is desirably composed of a protective film having no bright spot foreign matter, and a polarizing plate using a glass plate for protecting the polarizer is preferably used. The occurrence of bright spot foreign matter is considered to be one of the causes of unacetylated or low acetylated cellulose contained in the cellulose ester, as a countermeasure, using a cellulose ester with a small amount of unacetylated cellulose, Further, it can be removed and reduced by filtering the dope solution in which the cellulose ester is dissolved. Further, the thinner the film thickness, the smaller the number of bright spot foreign matter per unit area, and the lower the content of cellulose ester contained in the film, the fewer bright spot foreign matter.

The bright spot foreign matter having a bright spot diameter of 0.01 mm or more is preferably 200 pieces / cm ² or less, more preferably 100 pieces / cm ² or less, 50 pieces / cm ² or less, 30 pieces / cm. ² or less, preferably 10 pieces / cm ² or less, but it is particularly preferred that a 0.

Moreover, it is preferable that it is 200 pieces / cm < ² > or less also about 0.005 mm-0.01 mm bright spot, More preferably, it is 100 pieces / cm < ² > or less, 50 pieces / cm < ² > or less, 30 pieces / cm < ² > or less. The number is preferably 10 / cm ² or less, but particularly preferred is the case where the bright spot is zero. A thing with few also about a bright spot of 0.005 mm or less is preferable.

  When removing bright spot foreign matter by filtration, it is preferable to filter the composition in which a plasticizer is added and mixed, rather than filtering a cellulose ester dissolved alone, because the bright spot foreign matter removal efficiency is high. As the filter medium, conventionally known materials such as glass fibers, cellulose fibers, filter paper, and fluororesins such as tetrafluoroethylene resin are preferably used, but ceramics, metals and the like are also preferably used. The absolute filtration accuracy is preferably 50 μm or less, more preferably 30 μm or less, and 10 μm or less, and particularly preferably 5 μm or less.

  These can also be used in combination as appropriate. The filter medium can be either a surface type or a depth type, but the depth type is preferably used because it is relatively less clogged.

(Cyclic olefin resin film)
Next, the cyclic olefin resin film used in the present invention will be described.

  The cyclic olefin resin used in the present invention comprises a polymer resin containing an alicyclic structure.

  A preferable cyclic olefin resin is a resin obtained by polymerizing or copolymerizing a cyclic olefin. Examples of the cyclic olefin include norbornene, dicyclopentadiene, tetracyclododecene, ethyltetracyclododecene, ethylidenetetracyclododecene, tetracyclo [7.4.0.110, 13.02,7] trideca-2,4. Unsaturated hydrocarbons of polycyclic structures such as 6,11-tetraene and derivatives thereof; cyclobutene, cyclopentene, cyclohexene, 3,4-dimethylcyclopentene, 3-methylcyclohexene, 2- (2-methylbutyl) -1-cyclohexene, cyclo Examples thereof include monocyclic unsaturated hydrocarbons such as octene, 3a, 5,6,7a-tetrahydro-4,7-methano-1H-indene, cycloheptene, cyclopentadiene, cyclohexadiene, and derivatives thereof. These cyclic olefins may have a polar group as a substituent. Examples of the polar group include a hydroxyl group, a carboxyl group, an alkoxyl group, an epoxy group, a glycidyl group, an oxycarbonyl group, a carbonyl group, an amino group, an ester group, and a carboxylic acid anhydride group. Or a carboxylic anhydride group is preferred.

  Preferred cyclic olefin-based resins may be those obtained by addition copolymerization of monomers other than cyclic olefins. Addition copolymerizable monomers include ethylene, propylene, 1-butene, 1-pentene and other ethylene or α-olefins; 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl- Examples include dienes such as 1,4-hexadiene and 1,7-octadiene.

The cyclic olefin is obtained by an addition polymerization reaction or a metathesis ring-opening polymerization reaction. The polymerization is carried out in the presence of a catalyst. Examples of the addition polymerization catalyst include a polymerization catalyst composed of a vanadium compound and an organoaluminum compound. As a catalyst for ring-opening polymerization, a polymerization catalyst comprising a metal halide such as ruthenium, rhodium, palladium, osmium, iridium, platinum, nitrate or acetylacetone compound and a reducing agent; or titanium, vanadium, zirconium, tungsten, molybdenum Examples thereof include a polymerization catalyst comprising a metal halide such as acetylacetone compound and an organoaluminum compound. The polymerization temperature, pressure and the like are not particularly limited, but the polymerization is usually carried out at a polymerization temperature of -50 ° C to 100 ° C and a polymerization pressure of 0 to 490 N / cm ² .

  The cyclic olefin-based resin used in the present invention is preferably a resin obtained by polymerizing or copolymerizing a cyclic olefin, followed by a hydrogenation reaction to change the unsaturated bond in the molecule to a saturated bond. The hydrogenation reaction is performed by blowing hydrogen in the presence of a known hydrogenation catalyst. Examples of hydrogenation catalysts include cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, transition metal compounds such as titanocene dichloride / n-butyllithium, zirconocene dichloride / sec-butyllithium, tetrabutoxytitanate / dimethylmagnesium / alkyl. Homogeneous catalyst consisting of a combination of metal compounds; heterogeneous metal catalyst such as nickel, palladium, platinum; nickel / silica, nickel / diatomaceous earth, nickel / alumina, palladium / carbon, palladium / silica, palladium / diatomaceous earth And a heterogeneous solid-supported catalyst in which a metal catalyst such as palladium / alumina is supported on a carrier.

  Or the following norbornene-type polymer is also mentioned as cyclic olefin resin. The norbornene-based polymer preferably has a norbornene skeleton as a repeating unit. Specific examples thereof include JP-A-62-252406, JP-A-62-2252407, and JP-A-2-133413. JP-A-63-145324, JP-A-63-264626, JP-A-1-240517, JP-B-57-8815, JP-A-5-39403, JP-A-5-43663 JP-A-5-43834, JP-A-5-70655, JP-A-5-279554, JP-A-6-206985, JP-A-7-62028, JP-A-8-176411, Although what was described in Kaihei 9-241484 etc. can utilize preferably, it is not limited to these. Moreover, these may be used individually by 1 type and may use 2 or more types together.

  In the present invention, among the norbornene-based polymers, those having a repeating unit represented by any of the following structural formulas (I) to (IV) are preferable.

  In the structural formulas (I) to (IV), A, B, C and D each independently represent a hydrogen atom or a monovalent organic group.

  Among the norbornene-based polymers, a polymer obtained by metathesis polymerization of at least one compound represented by the following structural formula (V) or (VI) and an unsaturated cyclic compound copolymerizable therewith. A hydrogenated polymer obtained by hydrogenating is also preferred.

  In the structural formula, A, B, C and D each independently represent a hydrogen atom or a monovalent organic group.

  Here, A, B, C and D are not particularly limited, but preferably an organic group may be linked via a hydrogen atom, a halogen atom, a monovalent organic group, or at least a divalent linking group. These may be the same or different. A or B and C or D may form a monocyclic or polycyclic structure. Here, the at least divalent linking group includes a hetero atom typified by an oxygen atom, a sulfur atom, and a nitrogen atom, and examples thereof include ether, ester, carbonyl, urethane, amide, thioether, and the like. It is not limited. In addition, the organic group may be further substituted via the linking group.

  Examples of other monomers copolymerizable with the norbornene-based monomer include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, C2-C20 alpha olefins, such as 1-hexadecene, 1-octadecene, 1-eicocene, and derivatives thereof; cyclobutene, cyclopentene, cyclohexene, cyclooctene, 3a, 5,6,7a-tetrahydro-4,7 -Cycloolefins such as methano-1H-indene, and derivatives thereof; non 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene, etc. Conjugated dienes; and the like are used. Among these, an α-olefin, particularly ethylene is preferable.

  These other monomers copolymerizable with the norbornene-based monomer can be used alone or in combination of two or more. In the case of addition copolymerization of a norbornene monomer and another monomer copolymerizable therewith, the ratio of the structural unit derived from the norbornene monomer and the structural unit derived from the other monomer copolymerizable in the addition copolymer However, it is appropriately selected so that the mass ratio is usually 30:70 to 99: 1, preferably 50:50 to 97: 3, more preferably 70:30 to 95: 5.

  When the unsaturated bond remaining in the molecular chain of the synthesized polymer is saturated by a hydrogenation reaction, the hydrogenation rate is 90% or more, preferably 95% or more, particularly from the viewpoint of light resistance deterioration, weather resistance deterioration, etc. Preferably it is 99% or more.

  In addition, examples of the cyclic olefin resin used in the present invention include thermoplastic saturated norbornene resins described in paragraph Nos. [0014] to [0019] of JP-A No. 5-2108 and paragraph Nos. Of JP-A No. 2001-277430. [0015] to [0031] thermoplastic norbornene polymers, JP 2003-14901 paragraph Nos. [0008] to [0045] thermoplastic norbornene resins, JP 2003-139950 paragraph No. [0014] To [0028] norbornene-based resin composition, Japanese Patent Application Laid-Open No. 2003-161832, paragraph numbers [0029] to [0037], norbornene-based resin, Japanese Patent Application Laid-Open No. 2003-195268, paragraph numbers [0027] to [0036] The norbornene-based resin described in JP-A-2003-211589 Paragraph Nos. [0009] to [0023] alicyclic structure-containing polymer resin, norbornene polymer resin or vinyl alicyclic hydrocarbon heavy as described in paragraph Nos. [0008] to [0024] of JP-A No. 2003-111588 Examples include coalesced resins.

  Specifically, ZEONEX, ZEONOR manufactured by Nippon Zeon Co., Ltd., Arton manufactured by JSR Corporation, APPEL manufactured by Mitsui Chemicals, Inc. (APL8008T, APL6509T, APL6013T, APL5014DP, APL6015T) and the like are preferably used.

  The molecular weight of the cyclic olefin resin used in the present invention is appropriately selected according to the purpose of use, but is measured by a gel permeation chromatography method of a cyclohexane solution (a toluene solution when the polymer resin is not dissolved). When the polyisoprene or polystyrene-equivalent weight average molecular weight is usually in the range of 5,000 to 500,000, preferably 8,000 to 200,000, more preferably 10,000 to 100,000, the mechanical strength and molding processability of the molded body are high. It is preferable to be balanced.

  Moreover, when a low-volatile antioxidant is blended at a ratio of 0.01 to 5 parts by mass with respect to 100 parts by mass of the cyclic olefin-based resin, it effectively prevents the polymer from being decomposed or colored during the molding process. I can do it.

As the antioxidant, an antioxidant having a vapor pressure at 20 ° C. of 10 ⁻⁵ Pa or less, particularly preferably 10 ⁻⁸ Pa or less is desirable. Antioxidants having a vapor pressure higher than 10 ⁻⁵ Pa cause foaming during extrusion molding, and the antioxidants volatilize from the surface of the molded product when exposed to high temperatures.

  As an antioxidant which can be used by this invention, the following can be mentioned, for example, You may use 1 type in combination of these or several types.

  Hintard phenol type: 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butylphenol, 4-hydroxymethyl-2,6-di-t-butylphenol, 2,6-di -T-butyl-α-methoxy-p-dimethyl-phenol, 2,4-di-t-amylphenol, t-butyl-m-cresol, 4-t-butylphenol, styrenated phenol, 3-t-butyl- 4-hydroxyanisole, 2,4-dimethyl-6-tert-butylphenol, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 3,5-di-tert-butyl-4 -Hydroxybenzylphosphonate-diethyl ester, 4,4'-bisphenol, 4,4'-bis- (2,6-di-t-butylphenol), , 2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-methyl-6-α-methylcyclohexylphenol), 4,4'-methylene- Bis- (2-methyl-6-t-butylphenol), 4,4'-methylene-bis- (2,6-di-t-butylphenol), 1,1'-methylene-bis- (2,6-di -T-butylnaphthol), 4,4'-butylidene-bis- (2,6-di-t-butyl-meta-cresol), 2,2'-thio-bis- (4-methyl-6-t- Butylphenol), di-o-cresol sulfide, 2,2'-thio-bis- (2-methyl-6-tert-butylphenol), 4,4'-thio-bis (3-methyl-6-tert-butylphenol) 4,4'-thio-bis- (2, -Di-sec-amylphenol), 1,1'-thio-bis- (2-naphthol), 3,5-di-t-butyl-4-hydroxybenzyl ether, 1,6-hexanediol-bis- [ 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-tert-butylanilino) -1,3,5-triazine, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thiobis (4-methyl-6) -T-butylphenol), N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), bis (3,5-di-t-butyl-4-hydroxy) Benzylphospho Acid ethyl) calcium, 1,3,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, triethylene glycol-bis [3- (3- t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris -(3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxygenyl) propionate] and the like.

  Aminophenols: normal butyl-p-aminophenol, normal butyroyl-p-aminophenol, normal peragonoyl-p-aminophenol, normal lauroyl-p-aminophenol, normal stearoyl-p-aminophenol, 2,6 -Di-t-butyl-α-dimethyl, amino-p-cresol and the like.

  Hydroquinone series: hydroquinone, 2,5-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, hydroquinone methyl ether, hydroquinone monobenzyl ether, and the like.

  Phosphite triphosphite, tris (3,4-di-t-butylphenyl) phosphite, tris (nonylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene Phosphanite, 2-ethylhexyl octyl phosphite, etc.

  Others: 2-mercaptobenzothiazole zinc salt, dicatechol borate-di-o-tolylguanidine salt, nickel-dimethyldithiocarbamate, nickel-pentamethylene dithiocarbanate, mercaptobenzimidazole, 2-mercaptobenzimidazole zinc salt and the like.

  The cyclic olefin-based resin film may contain an additive that can be generally blended into a plastic film, if necessary. Examples of such additives include heat stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, lubricants, plasticizers, and fillers, and the content thereof is within a range that does not impair the purpose of the present invention. You can choose.

  There is no particular limitation on the method for forming the cyclic olefin-based resin film, and any of the hot melt molding method and the solution casting method can be used. The heat-melt molding method can be further classified into an extrusion molding method, a press molding method, an inflation molding method, an injection molding method, a blow molding method, a stretch molding method, etc. Among these methods, mechanical strength, surface accuracy are included. In order to obtain an excellent film, an extrusion molding method, an inflation molding method, and a press molding method are preferable, and an extrusion molding method is most preferable. The molding conditions are appropriately selected depending on the purpose of use and the molding method. In the case of the hot melt molding method, the cylinder temperature is usually in the range of 150 to 400 ° C, preferably 200 to 350 ° C, more preferably 230 to 330 ° C. Is set as appropriate. If the resin temperature is too low, fluidity will deteriorate, causing shrinkage and distortion in the film. If the resin temperature is too high, voids and silver streaks will occur due to thermal decomposition of the resin, and the film will turn yellow. Defects may occur. The thickness of the film is usually in the range of 5 to 300 μm, preferably 10 to 200 μm, more preferably 20 to 100 μm. When the thickness is too thin, handling at the time of lamination becomes difficult, and when it is too thick, the drying time after the lamination becomes long and the productivity is lowered.

  The width of the film is preferably 1.4 m or more from the viewpoint of productivity. More preferably, it is the range of 1.4-4m.

  The cyclic olefin resin film has a surface wetting tension of preferably 40 mN / m or more, more preferably 50 mN / m or more, and further preferably 55 mN / m or more. When the surface wetting tension is in the above range, the adhesive strength between the film and the polarizer is improved. In order to adjust the surface wetting tension, for example, corona discharge treatment, plasma discharge treatment, ozone spraying, ultraviolet irradiation, flame treatment, chemical treatment, and other known surface treatments can be performed.

  The sheet before stretching needs to have a thickness of about 50 to 500 μm, and the thickness unevenness is preferably as small as possible. The entire surface is within ± 8%, preferably within ± 6%, more preferably within ± 4%. is there.

  In order to make the cyclic olefin-based resin film into the retardation film according to the present invention, it is obtained by stretching the sheet at least in a uniaxial direction. In addition, it may be substantially uniaxial stretching, for example, biaxial stretching in which uniaxial stretching is performed in order to orient the molecules after stretching in a range that does not affect the molecular orientation. Biaxial stretching is preferable, and it is preferable to use the tenter device or the like for stretching.

  The draw ratio is 1.1 to 10 times, preferably 1.3 to 8 times, and a desired retardation may be set within this range. If the draw ratio is too low, the absolute value of the retardation does not rise to a predetermined value, and if it is too high, it may break.

  Stretching is usually performed in a temperature range of Tg to Tg + 50 ° C., preferably Tg to Tg + 40 ° C. of the resin constituting the sheet. If the stretching temperature is too low, the film breaks, and if it is too high, the molecular orientation is not achieved, so that it is difficult to obtain a desired retardation film.

  In the film thus obtained, molecules are oriented by stretching, and a retardation having a desired size can be obtained. When used as a retardation film, preferable retardation values in the present invention are Rt of 70 to 400 nm, Ro of 30 to 300 nm, and further preferably Ro of 30 to 70 nm.

  The retardation can be controlled by the retardation of the sheet before stretching, the stretching ratio, the stretching temperature, and the thickness of the stretched oriented film. When the sheet before stretching has a certain thickness, the larger the stretching ratio, the larger the absolute value of the retardation. Therefore, by changing the stretching ratio, it is possible to obtain a retardation film having a desired retardation. I can do it.

  The retardation variation is preferably as small as possible. The retardation film generally has a retardation variation of 550 nm within ± 10 nm, preferably ± 5 nm or less, more preferably ± 1 nm or less.

  Variations in thickness and thickness unevenness within the retardation can be reduced by using these small unstretched sheets, and by applying stress evenly to the sheets during stretching. For this purpose, it is desirable to stretch in a controlled temperature environment under a uniform temperature distribution, preferably within ± 5 ° C., more preferably within ± 2 ° C., particularly preferably within ± 0.5 ° C.

(Hard coat layer)
As for the polarizing plate protective film of this invention, it is preferable that a hard-coat layer is coated on the said base film. A method for producing an actinic radiation curable resin layer used as a hard coat layer will be described.

  In the polarizing plate protective film of the present invention, an active ray curable resin layer is preferably used as the hard coat layer.

  The actinic radiation curable resin layer refers to a layer mainly composed of a resin that cures through a crosslinking reaction or the like by irradiation with actinic rays such as ultraviolet rays or electron beams. As the actinic radiation curable resin, a component containing a monomer having an ethylenically unsaturated double bond is preferably used, and a hard coat layer is formed by curing by irradiation with actinic radiation such as ultraviolet rays or electron beams. Typical examples of the actinic radiation curable resin include an ultraviolet curable resin and an electron beam curable resin, and a resin curable by ultraviolet irradiation is preferable.

  As the ultraviolet curable resin, for example, an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, an ultraviolet curable polyol acrylate resin, or an ultraviolet curable epoxy resin is preferable. Used.

  UV curable acrylic urethane resins generally include 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter referred to as acrylates) in products obtained by reacting polyester polyols with isocyanate monomers or prepolymers. It can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate. For example, those described in JP-A-59-151110 can be used.

  For example, a mixture of 100 parts Unidic 17-806 (Dainippon Ink Co., Ltd.) and 1 part Coronate L (Nihon Polyurethane Co., Ltd.) is preferably used.

  Examples of UV curable polyester acrylate resins include those that are easily formed when 2-hydroxyethyl acrylate and 2-hydroxy acrylate monomers are generally reacted with polyester polyols. JP-A-59-151112 Can be used.

  Specific examples of the ultraviolet curable epoxy acrylate resin include an epoxy acrylate as an oligomer, a reactive diluent and a photoreaction initiator added thereto, and reacted to form an oligomer. The thing as described in 105738 can be used.

  Specific examples of UV curable polyol acrylate resins include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, etc. I can list them.

  Specific examples of the photoreaction initiator of these ultraviolet curable resins include benzoin and its derivatives, acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof. You may use with a photosensitizer. The photoinitiator can also be used as a photosensitizer. In addition, when using an epoxy acrylate photoinitiator, a sensitizer such as n-butylamine, triethylamine, or tri-n-butylphosphine can be used. The photoreaction initiator or photosensitizer used in the ultraviolet curable resin composition is 0.1 to 15 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the composition.

  Examples of the resin monomer include general monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, benzyl acrylate, cyclohexyl acrylate, vinyl acetate, and styrene as monomers having one unsaturated double bond. In addition, monomers having two or more unsaturated double bonds include ethylene glycol diacrylate, propylene glycol diacrylate, divinylbenzene, 1,4-cyclohexane diacrylate, 1,4-cyclohexyldimethyl adiacrylate, and the above trimethylolpropane. Examples thereof include triacrylate and pentaerythritol tetraacryl ester.

  Examples of commercially available ultraviolet curable resins that can be used in the present invention include ADEKA OPTMER KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (Asahi Denka ( Co., Ltd.); Koeihard A-101-KK, A-101-WS, C-302, C-401-N, C-501, M-101, M-102, T-102, D-102, NS -101, FT-102Q8, MAG-1-P20, AG-106, M-101-C (manufactured by Guangei Chemical Co., Ltd.); Seika Beam PHC2210 (S), PHC X-9 (K-3), PHC2213, DP -10, DP-20, DP-30, P1000, P1100, P1200, P1300, P1400, P1500, P1600, SCR900 (manufactured by Dainichi Seika Kogyo Co., Ltd.) KRM7033, KRM7039, KRM7130, KRM7131, UVECRYL29201, UVECRYL29202 (manufactured by Daicel UCB); RC-5015, RC-5016, RC-5020, RC-5031, RC-5100, RC-5102, RC-5120 RC-5122, RC-5152, RC-5171, RC-5180, RC-5181 (manufactured by Dainippon Ink & Chemicals, Inc.); 340 clear (manufactured by China Paint Co., Ltd.); Sunrad H-601, RC-750, RC-700, RC-600, RC-500, RC-611, RC-612 (manufactured by Sanyo Chemical Industries); SP -1509, SP-1507 (manufactured by Showa Polymer Co., Ltd.); RCC-15C (manufactured by Grace Japan Co., Ltd.), Aronix M-6100, M-8030, M-8060 (manufactured by Toagosei Co., Ltd.), etc. Can be selected as appropriate.

  Specific examples of compounds include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, and the like. .

  These actinic ray curable resin layers can be coated by a known method such as a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, or an ink jet method.

As a light source for curing an ultraviolet curable resin by a photocuring reaction to form a cured coating layer, any light source that generates ultraviolet rays can be used without any limitation. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. Irradiation conditions vary depending on each lamp, but the irradiation amount of active rays is preferably 5 to 150 mJ / cm ² , particularly preferably 20 to 100 mJ / cm ² .

  Moreover, when irradiating actinic radiation, it is preferable to carry out while applying tension | tensile_strength in the conveyance direction of a film, More preferably, it is performing applying tension | tensile_strength also in the width direction. The tension to be applied is preferably 30 to 300 N / m. The method for applying the tension is not particularly limited, and the tension may be applied in the conveying direction on the back roll, or the tension may be applied in the width direction or the biaxial direction by a tenter. This makes it possible to obtain a film having further excellent flatness.

  Examples of the organic solvent for the UV curable resin layer composition coating solution include hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), ketones (acetone, methyl ethyl ketone, methyl isobutyl). Ketone), esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, other organic solvents, or a mixture thereof. Propylene glycol monoalkyl ether (1 to 4 carbon atoms of the alkyl group) or propylene glycol monoalkyl ether acetate ester (1 to 4 carbon atoms of the alkyl group) is 5% by mass or more, more preferably 5 to 80%. It is preferable to use the organic solvent containing at least mass%.

  In addition, it is particularly preferable to add a silicon compound to the ultraviolet curable resin layer composition coating solution. For example, polyether-modified silicone oil is preferably added. The number average molecular weight of the polyether-modified silicone oil is, for example, 1000 to 100000, preferably 2000 to 50000. If the number average molecular weight is less than 1000, the drying property of the coating film decreases, and conversely, the number average When the molecular weight exceeds 100,000, it tends to be difficult to bleed out to the coating surface.

  Commercially available silicon compounds include DKQ8-779 (trade name, manufactured by Dow Corning), SF3771, SF8410, SF8411, SF8419, SF8421, SF8428, SH200, SH510, SH1107, SH3749, SH3771, BX16-034, SH3746, SH3749, SH8400, SH3771M, SH3772M, SH3773M, SH3775M, BY-16-837, BY-16-839, BY-16-869, BY-16-870, BY-16-004, BY-16-891, BY-16 872, BY-16-874, BY22-008M, BY22-012M, FS-1265 (above, product names manufactured by Toray Dow Corning Silicone), KF-101, KF-100T, KF351, KF3 2, KF353, KF354, KF355, KF615, KF618, KF945, KF6004, Silicone X-22-945, X22-160AS (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), XF3940, XF3949 (trade name, manufactured by Toshiba Silicone Co., Ltd.) ), Disparon LS-009 (manufactured by Enomoto Kasei Co., Ltd.), Granol 410 (manufactured by Kyoeisha Oil Chemical Co., Ltd.), TSF4440, TSF4441, TSF4445, TSF4446, TSF4452, TSF4460 (manufactured by GE Toshiba Silicone), BYK-306, BYK- 330, BYK-307, BYK-341, BYK-344, BYK-361 (manufactured by BYK-Japan) L series (for example, L7001, L-7006, L-7604, L-9000) manufactured by Nippon Unicar Co., Ltd. Y Over's, FZ series (FZ-2203, FZ-2206, FZ-2207) and the like, are preferably used.

  These components enhance the applicability to the substrate and the lower layer. When added to the outermost surface layer of the laminate, it not only improves the water repellency, oil repellency and antifouling properties of the coating film, but also exhibits an effect on the scratch resistance of the surface. These components are preferably added in a range of 0.01 to 3% by mass with respect to the solid component in the coating solution.

  As a coating method of the ultraviolet curable resin composition coating solution, the above-described methods can be used. The coating amount is suitably 0.1 to 30 μm, preferably 0.5 to 15 μm, as the wet film thickness. The dry film thickness is 0.1 to 20 μm, preferably 1 to 10 μm.

The ultraviolet curable resin composition is preferably irradiated with ultraviolet rays during or after coating and drying, and the irradiation time for obtaining the active ray irradiation amount of 5 to 150 mJ / cm ² is from 0.1 seconds to 5 seconds. Minutes are good, and 0.1 to 10 seconds is more preferable from the viewpoint of curing efficiency or work efficiency of the ultraviolet curable resin.

Moreover, it is preferable that the illuminance of these active ray irradiation parts is 50-150 mW / cm < ² >.

  In order to prevent blocking, to improve scratch resistance, to give antiglare property or light diffusibility, and to adjust the refractive index in the cured resin layer thus obtained, fine particles of an inorganic compound or an organic compound Can also be added.

  Inorganic fine particles used in the hard coat layer include silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, silicic acid Mention may be made of aluminum, magnesium silicate and calcium phosphate. In particular, silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide and the like are preferably used.

  The organic fine particles include polymethacrylic acid methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder. Polyolefin resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, or polyfluoroethylene resin powder can be added to the ultraviolet curable resin composition. Particularly preferred are cross-linked polystyrene particles (for example, SX-130H, SX-200H, SX-350H, manufactured by Soken Chemical) and polymethyl methacrylate-based particles (for example, MX150, MX300, manufactured by Soken Chemical).

  The average particle diameter of these fine particle powders is preferably 0.005 to 5 μm, and particularly preferably 0.01 to 1 μm. As for the ratio of a ultraviolet curable resin composition and fine particle powder, it is desirable to mix | blend so that it may be 0.1-30 mass parts with respect to 100 mass parts of resin compositions.

  The ultraviolet curable resin layer is a clear hard coat layer having a center line average roughness (Ra) defined by JIS B 0601 of 1 to 50 nm or an antiglare layer having an Ra of about 0.1 to 1 μm. Is preferred. The center line average roughness (Ra) is preferably measured with an optical interference type surface roughness measuring instrument, and can be measured using, for example, RST / PLUS manufactured by WYKO.

(Antireflection layer)
On the polarizing plate protective film having the hard coat layer according to the present invention, an antireflection layer can be further provided to form an antireflection film.

  The antireflection layer applicable to the present invention preferably comprises a plurality of refractive index layers provided on the hard coat layer from the hard coat layer side, and further comprises a high refractive index layer and a low refractive index layer laminated in this order. Preferably there is. The level of refractive index is largely determined by the metal or compound contained therein, for example, Ti is high, Si is low, F-containing compounds are further low, and the refractive index is set by such a combination. The refractive index and the film thickness can be calculated and calculated by measuring the spectral reflectance.

  In the antireflection film of the present invention, each antireflection layer is preferably laminated in consideration of the refractive index, the film thickness, the number of layers, the layer order, and the like so that the reflectance is reduced by optical interference. The antireflection layer is formed by combining a high refractive index layer having a higher refractive index than that of the support and a low refractive index layer having a lower refractive index than that of the support. Particularly preferably, it is an antireflection layer composed of three or more refractive index layers, three layers having different refractive indexes from the support side, a medium refractive index layer (having a higher refractive index than the support or hard coat layer, Layers having a refractive index lower than that of the high refractive index layer) / high refractive index layer / low refractive index layer are preferably used in this order. Alternatively, an antireflection layer having a layer structure of four or more layers in which two or more high refractive index layers and two or more low refractive index layers are alternately laminated is also preferably used.

  In addition, if necessary, it is also preferable to further provide an antifouling layer on the outermost low refractive index layer so that dirt and fingerprints can be easily wiped off. As the antifouling layer, a fluorine-containing organosilane compound is preferably used.

The antireflection layer applicable to the present invention can be formed by a coating method, and can be formed by a metal oxide layer, a metal oxynitride layer (SiO ₂ , TiO ₂ , Ta ₂₎ by a dry process such as atmospheric pressure plasma treatment or CVD. _{O 5, ZrO 2, ZnO,} SnO 2, ITO, SiN, TiN, SiO x N y, SiO x, TiO x, such as TiO _x N _y) can be provided. In the present invention, it is preferable to form the antireflection layer by a coating method.

  In the present invention, the high refractive index layer preferably contains titanium oxide. These are layers having a refractive index of 1.55 to 2.5 formed by applying and drying a coating liquid containing fine particles, monomers of organic titanium compounds, oligomers or hydrolysates thereof.

Examples of the monomer or oligomer of the organic titanium compound used in the present invention include Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (On-C ₃ H ₇ ) ₄ , Ti (O-i- _{C 3 H 7) 4, Ti} (O-n-C 4 H 9) 4, Ti (O-n-C 3 H 7) 4 2-10 mer, Ti (O-i-C 3 H 7) Preferred examples include ₄ to 10 mer of ₄ and 2 to 10 mer of Ti (On-C ₄ H ₉ ) ₄ . These may be used alone or in combination of two or more. Of these _{Ti (O-n-C 3} H 7) 4, Ti (O-i-C 3 H 7) 4, Ti (O-n-C 4 H 9) 4, Ti (O-n-C 3 H 7 ) ₄ to 10-mer and Ti (On-C ₄ H ₉ ) ₄ to 10-mer are particularly preferable.

  The monomer, oligomer or hydrolyzate of the organic titanium compound used in the present invention preferably occupies 50.0% by mass to 98.0% by mass in the solid content contained in the coating solution. The solid content ratio is more preferably 50% by mass to 90% by mass, and further preferably 55% by mass to 90% by mass. In addition, it is also preferable to add a polymer of an organic titanium compound (a product obtained by previously hydrolyzing an organic titanium compound to be crosslinked) or titanium oxide fine particles to the coating composition.

  Further, in the present invention, the coating liquid contains the above-mentioned organotitanium compound monomer, oligomer part or complete hydrolyzate, but the organotitanium compound monomer and oligomer are self-condensed, crosslinked and network-bonded. is there. Catalysts and curing agents can be used to accelerate the reaction, including metal chelate compounds, organometallic compounds such as organic carboxylates, organosilicon compounds having amino groups, and acid generation by light. Agent (photoacid generator). Of these catalysts or curing agents, an aluminum chelate compound and a photoacid generator are particularly preferred. Examples of aluminum chelate compounds are ethyl acetoacetate aluminum diisopropylate, aluminum trisethyl acetoacetate, alkyl acetoacetate aluminum diisopropylate, aluminum monoacetylacetonate bisethylacetoacetate, aluminum trisacetylacetonate, etc. Examples of the acid generator include benzyltriphenylphosphonium hexafluorophosphate, other phosphonium salts, and triphenylphosphonium hexafluorophosphate salts.

  It is preferable that 0.5 mass%-20 mass% of binder is contained as a solid content ratio in the coating liquid of an antireflection layer.

  As a binder, it is a coating layer having two or more polymerizable groups such as a polymerizable vinyl group, allyl group, acryloyl group, methacryloyl group, isopropenyl group, epoxy group, oxetane ring, and containing an actinic radiation curable resin. The same acrylic or methacrylic active energy ray reactive compound, epoxy active energy ray reactive compound, or oxetane active energy ray reactive compound as used can be used. These compounds include monomers, oligomers and polymers. Of these active groups, an acryloyl group, a methacryloyl group or an epoxy group is preferable from the viewpoint of polymerization rate and reactivity, and a polyfunctional monomer or oligomer is more preferable. Moreover, the actinic radiation curable resin used for the coating layer and hard-coat layer containing the above-mentioned actinic radiation curable resin can also be used preferably. Furthermore, an alcohol-soluble acrylic resin is also preferably used.

  Among the titanium compounds, an alcohol-soluble acrylic resin is also preferably used as the binder for the high refractive index layer, whereby a high refractive index layer can be obtained with little film thickness unevenness. Specifically, an alkyl (meth) acrylate polymer or an alkyl (meth) acrylate copolymer, for example, a copolymer such as n-butyl methacrylate, isobutyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, is preferably used. The copolymer component is not limited to these. Commercially available products include Dianal BR-50, BR-51, BR-52, BR-60, BR-64, BR-65, BR-70, BR-73, BR-75, BR-76, BR-77. , BR-79, BR-80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-89, BR-90, BR-93, BR-95, BR-96, BR -100, BR-101, BR-102, BR-105, BR-107, BR-108, BR-112, BR-113, BR-115, BR-116, BR-117, BR-118 (above, Mitsubishi Can be used. These monomer components can also be added as a binder for the medium to high refractive index layer. The refractive index can be adjusted by changing the addition ratio of the binder.

  The low refractive index layer used in the present invention is preferably provided by coating silicon compound fine particles such as silicon oxide or fluorine-containing compound fine particles. Examples of preferable organosilicon compounds include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, and the like. An oligomer is obtained. The hydrolysis reaction can be carried out by a known method. For example, a predetermined amount of water is added to the tetraalkoxysilane, and the by-product alcohol is distilled off in the presence of an acid catalyst. React at 100 ° C. By this reaction, the alkoxysilane is hydrolyzed, followed by a condensation reaction, and a liquid silicate oligomer having two or more hydroxyl groups (usually the average degree of polymerization is 2 to 8, preferably 3 to 6) as a hydrolyzate. Can be obtained.

  Examples of the curing catalyst include acids, alkalis, organic metals, metal alkoxides and the like. In the present invention, acids, particularly organic acids having a sulfonyl group or a carboxyl group are preferably used. For example, acetic acid, polyacrylic acid, benzenesulfonic acid, p-toluenesulfonic acid, methylsulfonic acid and the like are used. The organic acid is more preferably a compound having a hydroxyl group and a carboxyl group in one molecule. For example, a hydroxydicarboxylic acid such as citric acid or tartaric acid is used. The organic acid is more preferably a water-soluble acid. For example, in addition to the citric acid and tartaric acid, levulinic acid, formic acid, propionic acid, malic acid, succinic acid, methyl succinic acid, fumaric acid, oxaloacetic acid, pyruvin. Acid, 2-oxoglutaric acid, glycolic acid, D-glyceric acid, D-gluconic acid, malonic acid, maleic acid, oxalic acid, isocitric acid, lactic acid and the like are preferably used. Also, benzoic acid, hydroxybenzoic acid, atorvaic acid and the like can be used as appropriate.

  By using the above-mentioned organic acids, not only can the piping corrosion and safety concerns during production due to the use of inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, hypochlorous acid, and boric acid be eliminated, but also during hydrolysis. A stable hydrolyzate can be obtained without causing gelation. The addition amount is 0.1 to 10 parts by mass, preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the partial hydrolyzate. In addition, the amount of water added may be equal to or greater than the amount that the partial hydrolyzate can theoretically hydrolyze to 100%, and an amount equivalent to 100 to 300%, preferably an amount equivalent to 100 to 200% is added.

  The coating composition for the low refractive index layer thus obtained is extremely stable.

  Further, in the present invention, the aging step sufficiently proceeds the hydrolysis and condensation of the organosilicon compound, and the resulting film has excellent properties. For the aging, the oligomer liquid may be allowed to stand, and the standing time is a time for which the above-described crosslinking proceeds to a degree sufficient to obtain desired film characteristics. Specifically, although it depends on the type of catalyst used, it is sufficient for hydrochloric acid to be 1 hour or more at room temperature, for maleic acid to be several hours or more, and about 8 hours to 1 week, usually around 3 days. The ripening temperature affects the ripening time, and it may be better to take a means of heating to around 20 ° C. in extremely cold regions. In general, ripening progresses quickly at high temperatures, but when heated to 100 ° C. or higher, gelation occurs. Therefore, heating to 50 to 60 ° C. at best is appropriate. In addition to the above, the silicate oligomer used in the present invention is a modified product modified with an organic compound (monomer, oligomer, polymer) having a functional group such as an epoxy group, an amino group, an isocyanate group, or a carboxyl group. It may be present alone or in combination with the above silicate oligomer.

  In the present invention, silicon oxide fine particles can be contained in the low refractive index layer. It is preferable to include silicon oxide fine particles having a particle size of 0.1 μm or less. For example, Aerosil 200V (manufactured by Nippon Aerosil Co., Ltd.) or the like can be added. In particular, silicon oxide fine particles whose surface is modified with an alkyl group are preferably used. For example, silicon oxide fine particles whose surface is modified with a methyl group are commercially available as Aerosil R972 and R972V (manufactured by Nippon Aerosil Co., Ltd.). Can be added. In addition, it is also possible to use silicon oxide fine particles whose surface is substituted with an alkyl group as described in JP-A-2001-2799, and it is easy to treat with an alkylsilane coupling agent after hydrolysis of the silicate oligomer. Can be obtained. As an addition amount, it is preferable to add so that it may become the range of 0.1 mass%-40 mass% in the solid content ratio in a low-refractive-index layer.

  Further, in the present invention, hollow spherical silica-based fine particles having an outer shell layer and having a porous or hollow inside, as described in JP-A Nos. 2001-167737, 2001-233611, 2002-79616, etc. It is also preferable to use. The hollow spherical fine particles are (I) composite particles comprising porous particles and a coating layer provided on the surface of the porous particles, or (II) having cavities inside, and the content is a solvent, gas or porous Cavity particles filled with a substance. Note that the low refractive index layer only needs to contain either (I) composite particles or (II) hollow particles, or both.

  The hollow particles are particles having cavities inside, and the cavities are surrounded by particle walls. The cavity is filled with contents such as a solvent, a gas, or a porous material used at the time of preparation. It is desirable that the average particle diameter of such hollow spherical fine particles is in the range of 5 to 300 nm, preferably 10 to 200 nm.

  A silane compound can be further added to each refractive index layer of the present invention in order to adjust the refractive index or improve the film quality.

  Solvents used in the coating solution for coating the high, medium and low refractive index layers used in the present invention are alcohols such as methanol, ethanol, 1-propanol, 2-propanol and butanol; acetone, methyl ethyl ketone, cyclohexanone Ketones such as benzene, toluene, xylene, etc .; glycols such as ethylene glycol, propylene glycol, hexylene glycol; ethyl cellosolve, butylcellosolve, ethylcarbitol, butylcarbitol, diethylcell Glycol ethers such as sorb, diethyl carbitol, propylene glycol monomethyl ether; N-methylpyrrolidone, dimethylformamide, methyl lactate, ethyl lactate, water, etc. are mentioned, and these should be used alone or in combination of two or more. Can.

  Further, those having an ether bond in the molecule are particularly preferred, and glycol ethers are more preferred.

  Examples of glycol ethers include propylene glycol mono (C1-C4) alkyl ether and propylene glycol mono (C1-C4) alkyl ether ester, specifically, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene Examples thereof include glycol mono n-propyl ether, propylene glycol monoisopropyl ether, propylene glycol monobutyl ether and the like. Examples of the propylene glycol mono (C1 to C4) alkyl ether ester include propylene glycol monoalkyl ether acetate, and specific examples include propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate. These solvents are preferably added in an amount of 1% to 90% by mass of the total organic solvent in the coating solution.

  Various additives can be added to the coating solution for each of the high, medium and low refractive index layers used in the present invention.

  For example, it is preferable to add a slipping agent to the low refractive index layer, and scratch resistance can be improved by imparting slipperiness. As the slip agent, silicon oil or a wax-like substance is preferably used.

  Specifically, higher fatty acids such as behenic acid, stearamide, and pentacoic acid, or derivatives thereof, and carnauba wax, beeswax, and montan wax containing many of these components as natural products can also be preferably used. Polyorganosiloxanes as disclosed in Japanese Patent Publication No. 53-292, higher fatty acid amides as disclosed in US Pat. No. 4,275,146, Japanese Patent Publication No. 58-33541, British Patent No. 927,446 Higher fatty acid esters (esters of fatty acids having 10 to 24 carbon atoms and alcohols having 10 to 24 carbon atoms), and U.S. Patents, as disclosed in JP-A-55-126238 and 58-90633 From higher fatty acid metal salts as disclosed in US Pat. No. 3,933,516, and dicarboxylic acids having up to 10 carbon atoms and aliphatic or cycloaliphatic diols as disclosed in JP-A-51-37217. Polyester compounds, and oligopolyesters from dicarboxylic acids and diols disclosed in JP-A-7-13292 Can.

The addition amount of the slip agent used in the low refractive index layer is preferably ^{0.01mg / m 2 ~10mg / m 2} . If necessary, it can be added to the middle refractive index layer or the high refractive index layer.

  Among the high refractive index layer and the low refractive index layer used in the present invention, it is preferable to add a surfactant, a softening agent, a softening smoothing agent, etc., thereby improving the scratch resistance. Among these, anionic or nonionic surfactants are preferable, and for example, dialkylsulfosuccinic acid sodium salt, nonionic surfactant emulsion of polyhydric alcohol fatty acid ester, and the like are preferable. For example, lipooil NT-6, NT12, NT-33, TC-1, TC-68, TC-78, CW-6, TCF-208, TCF-608, NK oil CS-11, AW-9, AW-10 , AW-20, polysofter N-606, paint additive PC-700 (manufactured by Nikka Chemical Co., Ltd.) and the like are used.

  Among the materials used in the present invention, it is preferable to irradiate actinic rays after the coating of the high refractive index layer and the low refractive index layer in order to promote hydrolysis or curing of the composition containing the metal alkoxide. More preferably, the active energy ray is irradiated every time each layer is coated.

The actinic radiation used in the present invention can use the same light source as that used for curing the actinic radiation curable resin layer. Irradiation conditions vary depending on individual lamps, irradiation dose is preferably ^{20mJ / cm 2 ~10000mJ / cm 2} , more preferably from ^{100mJ / cm 2 ~2000mJ / cm 2} , particularly preferably 400 mJ / cm ² ~ 2000 mJ / cm ² .

  When ultraviolet rays are used, the multilayer antireflection layer may be irradiated one by one or after lamination, but it is particularly preferable to irradiate the ultraviolet rays after the multilayers are laminated.

(Polarizer)
The polarizing plate according to the present invention is obtained by bonding protective films on both surfaces of a polarizing film in which a dichroic dye is adsorbed and oriented on a uniaxially stretched polyvinyl alcohol resin film. The polyvinyl alcohol-based resin constituting the polarizing film is usually obtained by saponifying a polyvinyl acetate-based resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerized with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, and unsaturated sulfonic acids. The degree of saponification of the polyvinyl alcohol resin is usually 85 to 100 mol%, preferably 98 to 100 mol%. This polyvinyl alcohol-based resin may be further modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol-based resin is usually 1000 to 10,000, preferably 1500 to 10,000.

  A polarizing plate usually has a process of uniaxially stretching such a polyvinyl alcohol resin film, a process of dyeing a polyvinyl alcohol resin film with a dichroic dye to adsorb iodine or a dichroic dye, and a dichroic dye adsorbing. A step of treating the obtained polyvinyl alcohol resin film with an aqueous boric acid solution, a step of washing with water after the treatment with the boric acid aqueous solution, and a uniaxially stretched polyvinyl alcohol resin film on which the dichroic dye is adsorbed and oriented by these steps It is manufactured through a process of pasting a protective film. Uniaxial stretching may be performed before dyeing with a dichroic dye, may be performed simultaneously with dyeing with a dichroic dye, or may be performed after dyeing with a dichroic dye. When uniaxial stretching is performed after dyeing with a dichroic dye, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. Of course, it is also possible to perform uniaxial stretching in these plural stages. For uniaxial stretching, rolls having different peripheral speeds may be uniaxially stretched or uniaxially stretched using a hot roll. Moreover, the dry-type extending | stretching which extends | stretches in air | atmosphere may be sufficient, and the wet extending | stretching which extends | stretches in the state swollen with the solvent may be sufficient. The draw ratio is usually about 4 to 8 times.

  In order to dye the polyvinyl alcohol resin film with the dichroic dye, for example, the polyvinyl alcohol resin film may be immersed in an aqueous solution containing the dichroic dye. The dichroic dye referred to here is specifically iodine or a dichroic dye.

  When iodine is used as the dichroic dye, a method of dyeing a polyvinyl alcohol resin film by dipping in an aqueous solution containing iodine and potassium iodide is usually employed. The content of iodine in this aqueous solution is usually about 0.01 to 0.5 parts by mass per 100 parts by mass of water, and the content of potassium iodide is usually about 0.5 to 10 parts by mass per 100 parts by mass of water. It is. The temperature of this aqueous solution is usually about 20 to 40 ° C., and the immersion time in this aqueous solution is usually about 30 to 300 seconds.

On the other hand, when a dichroic dye is used as the dichroic dye, a method of immersing and dyeing a polyvinyl alcohol-based resin film in an aqueous solution containing a water-soluble dichroic dye is usually employed. The content of the dichroic dye in this aqueous solution is usually about 1 × 10 ⁻³ to 1 × 10 ⁻² parts by mass per 100 parts by mass of water. This aqueous solution may contain an inorganic salt such as sodium sulfate. The temperature of this aqueous solution is usually about 20 to 80 ° C., and the immersion time in this aqueous solution is usually about 30 to 300 seconds.

  The boric acid treatment after dyeing with a dichroic dye is performed by immersing the dyed polyvinyl alcohol resin film in an aqueous boric acid solution. The boric acid content in the boric acid aqueous solution is usually about 2 to 15 parts by mass, preferably about 5 to 12 parts by mass per 100 parts by mass of water. When iodine is used as the dichroic dye, the aqueous boric acid solution preferably contains potassium iodide. The content of potassium iodide in the boric acid aqueous solution is usually about 2 to 20 parts by mass, preferably 5 to 15 parts by mass per 100 parts by mass of water. The immersion time in the boric acid aqueous solution is usually about 100 to 1,200 seconds, preferably about 150 to 600 seconds, and more preferably about 200 to 400 seconds. Moreover, the temperature of boric acid aqueous solution is 50 degreeC or more normally, Preferably it is 50-85 degreeC.

  The polyvinyl alcohol resin film after the boric acid treatment is usually washed with water. The water washing treatment is performed, for example, by immersing a boric acid-treated polyvinyl alcohol resin film in water. After washing with water, a drying process is performed to obtain a polarizing film. The temperature of water in the water washing treatment is usually about 5 to 40 ° C., and the immersion time is usually about 2 to 120 seconds. The drying process performed thereafter is usually performed using a hot air dryer or a far infrared heater. The drying temperature is usually 40 to 100 ° C. The processing time in the drying process is usually about 120 seconds to 600 seconds.

  Although there is no restriction | limiting in particular in the width | variety of a polarizing film, The width same as the width | variety of an above described polarizing plate protective film or retardation film is preferable, Specifically, the film width of 1.4 m or more is preferable, and especially 1.4m-4m. preferable.

  The polarizing film thus obtained is made into a polarizing plate by laminating a polarizing plate protective film or a retardation film on both sides in the same manner as a normal polarizing film.

  At that time, the film to be laminated may be a strip-like sheet or a roll. Furthermore, each combination may be sufficient. Since it can be laminated | stacked by roll-to-roll if it is a roll-shaped thing, it is preferable because it is excellent in productivity.

  In preparation of the polarizing plate of this invention, when using a cyclic olefin resin film as a phase difference film, it is preferable to provide an adhesive layer on the cyclic olefin resin film side, and to bond.

  When a cellulose ester film is used as the protective film or retardation film, the surface is preferably saponified with an alkaline aqueous solution prior to bonding with a polarizer.

  Furthermore, the same applies to the case where there are protective films on both sides of the polarizer and the retardation film is further bonded to one surface thereof.

  As described above, the pressure-sensitive adhesive layer is provided on the surface of the polarizing plate on which the polarizing plate protective film, the polarizer, and the retardation film are bonded to contact the liquid crystal cell, thereby forming the polarizing plate of the present invention.

(Display device)
By incorporating the polarizing plate having the pressure-sensitive adhesive layer of the present invention into a display device, particularly a liquid crystal display device, various liquid crystal display devices with excellent visibility can be produced. The polarizing plate of the present invention is preferably a reflective, transmissive, transflective LCD or TN, STN, OCB, HAN, VA (PVA, MVA), or IPS LCD. Used. In particular, in a large-screen liquid crystal display device having a 30-inch or larger screen, light leakage is remarkably reduced, color unevenness and wavy unevenness are reduced, and eyes are not tired even during long-time viewing.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Example 1
<Production of polarizing plate>
A polyvinyl alcohol film having a thickness of 120 μm was uniaxially stretched (temperature: 110 ° C., stretch ratio: 5 times). This was immersed in an aqueous solution composed of 0.075 g of iodine, 5 g of potassium iodide and 100 g of water for 60 seconds, and then immersed in an aqueous solution of 68 ° C. composed of 6 g of potassium iodide, 7.5 g of boric acid and 100 g of water. This was washed with water and dried to obtain a polarizing film.

  Next, as a polarizing film and a polarizing plate protective film according to the following steps 1 to 5, Konica Minolta Op KC8UXW-H (polarizing plate protective film with hard coat) and Konica Minolta Tack KC8UCR4 (retardation film) are manufactured as Konica Minolta Opto Co., Ltd. A polarizing plate was used.

  Step 1: The polarizing plate protective film was immersed in a 2 mol / L sodium hydroxide solution at 60 ° C. for 90 seconds, then washed with water and dried to obtain a saponified cellulose ester film.

  Step 2: The polarizing film was immersed in a polyvinyl alcohol adhesive tank having a solid content of 2% by mass for 1 to 2 seconds.

  Step 3: Excess adhesive adhered to the polarizing film in Step 2 was lightly wiped off and placed so as to be sandwiched between the two polarizing plate protective films saponified in Step 1. At that time, lamination was performed so that the hard coat layer was on the outside.

Step 4: pressure 20-30 N / cm ² the laminated film sample in step 3, the conveying speed was pasted at approximately 2m / min.

  Process 5: The sample bonded in the process 4 in an 80 ° C. dryer was dried to obtain a polarizing plate.

  The following adhesive layer is provided on the retardation film side surface of this polarizing plate by an ink jet method, and the following adhesive layer ink is provided in a pattern with a lower storage elastic modulus in the peripheral portion with respect to the central portion. . 1-8 were obtained. In addition, it was made to change continuously in the boundary part of the adhesion layer from which an elasticity modulus differs.

  The formation pattern of the pressure-sensitive adhesive layer and the type of pressure-sensitive adhesive used are shown in Table 1 below. The formation patterns a to e are shown in FIG.

  The method for preparing the pressure-sensitive adhesives A to M used and the storage elastic modulus at 25 ° C. are shown below. In addition, the measuring method of a storage elastic modulus is as follows.

(Measurement method of storage modulus of adhesive layer)
Each adhesive layer molding composition was formed on a polyethylene terephthalate film support. The adhesive layer was peeled off, and the adhesive layer was stored at 25 ° C. in a temperature rising mode (temperature rising rate 5 ° C./min, frequency 10 Hz) by a dynamic viscoelasticity measuring device (“ARES” manufactured by Rheometric Co.). The elastic modulus was measured.

(Adhesive layer A)
<Preparation of organic layered clay mineral>
20 g of saponite layered clay mineral (cation exchange capacity 90 meq / 100 g) was stirred and dispersed in 400 g of distilled water. A quaternary ammonium salt having a polyoxypropylene group represented by the formula (1) (wherein R ^{1 to} R ³ are methyl groups and n is 25) 47.3 g, water 100 g, and ethanol 100 g are uniformly mixed. This was added to the dispersion of the layered clay mineral and stirred at 30 ° C. for 1 hour. The precipitated solid was separated by filtration and dried by freeze-drying to obtain a waxy organically modified layered clay mineral. The interlayer distance of this organized layered clay mineral was 42 mm by X-ray scattering analysis. Moreover, the content of the organic ammonium ion in the organic layered clay mineral was 60% by mass as a result of thermogravimetric analysis.

<Preparation of adhesive layer>
The above-mentioned organically modified layered clay mineral 54 g and 2-ethylhexyl acrylate 90 g were mixed with a three-one motor for 2 hours to obtain a cloudy dispersion. The dispersion was subjected to a treatment for about 3 minutes at an irradiation intensity of 500 W while being dispersed by an ultrasonic disperser (manufactured by Nippon Seiki Co., Ltd.) to add an external action. Thereby, the dispersion became transparent from white turbidity. As a result of X-ray scattering analysis, the 4.2 nm peak of the organic layered clay mineral disappeared, and a peak showing a broad spread on the low angle side exceeding 10 nm was observed. From this, it was confirmed that the monomer was inserted between the layers of the organically modified layered clay mineral.

Thus, 0.1 part of 1-hydroxycyclohexyl phenyl ketone (“Irgacure 184” manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator per 100 parts of the solid content of the dispersion having an external action added thereto, a cross-linking agent As a result, 0.2 part of trimethylolpropane triacrylate was added and dissolved uniformly. After applying this transparent adhesive composition to a thickness of 10 μm by an ink jet method, photopolymerization was performed by irradiating 900 mJ / cm ² of ultraviolet rays with a high-pressure mercury lamp having a light intensity of 5 mW / cm ^{2 in} a nitrogen gas atmosphere. I let you.

  By X-ray scattering analysis of the adhesive layer, it was confirmed that the low-angle broad peak observed in the dispersion before photopolymerization further decreased, and that the interlayer separation of the organically modified layered clay mineral was further progressed.

The storage elastic modulus of the adhesive layer A at 25 ° C. was 5.5 × 10 ⁵ Pa.

(Adhesive layer B)
<Preparation of adhesive layer>
10 g of the organically modified layered clay mineral obtained in the adhesive layer A and 90 g of 2-ethylhexyl acrylate were mixed with a three-one motor for 2 hours to obtain a cloudy dispersion. This dispersion was subjected to a treatment for 30 minutes at 20000 rpm using a high shear type dispersion device (“Clear Mix” manufactured by M Technique Co., Ltd.) to add an external action. Thereby, the dispersion became transparent from white turbidity. As a result of X-ray scattering analysis, the 4.2 nm peak of the organic layered clay mineral disappeared, and a peak showing a broad spread on the low angle side exceeding 10 nm was observed. From this, it was confirmed that the monomer was inserted between the layers of the organically modified layered clay mineral.

  To the dispersion thus added with an external action, 0.1 part of the same photopolymerization initiator as that of the pressure-sensitive adhesive layer A and 0.2 part of the same cross-linking agent as that of the pressure-sensitive adhesive layer A are added per 100 parts of the solid content. Dissolved in. The transparent pressure-sensitive adhesive composition was applied by an ink jet method in the same manner as the pressure-sensitive adhesive layer A, and then photopolymerized.

The storage elastic modulus at 25 ° C. of the adhesive layer B was 9.3 × 10 ⁴ Pa. (17% with respect to adhesive layer A)
(Adhesive layer C)
An adhesive layer C was prepared in the same manner except that the amount of the organically modified layered clay mineral was changed to 2 g when the adhesive layer A was produced.

The storage elastic modulus of the adhesive layer C at 25 ° C. was 3.2 × 10 ⁴ Pa. (6% with respect to adhesive layer A)
(Adhesive layer D)
<Preparation of adhesive layer>
Organized layered clay mineral 80g used for adhesive layer A, 80g 2-ethylhexyl acrylate, 0.2g 1-hydroxycyclohexyl phenyl ketone ("Irgacure 184" manufactured by Ciba Specialty Chemicals) as photopolymerization initiator and toluene as organic solvent 280 g was mixed with a three-one motor for 2 hours to obtain a dispersion. The dispersion was subjected to a treatment for about 3 minutes at an irradiation intensity of 500 w while being dispersed by an ultrasonic disperser (manufactured by Nippon Seiki Co., Ltd.) to add an external action. As a result of X-ray scattering analysis, the 4.2 nm peak of the organic layered clay mineral disappeared, and a peak showing a broad spread on the low angle side exceeding 10 nm was observed. From this, it was confirmed that a monomer, a photopolymerization initiator, and a part of the organic solvent were inserted between the layers of the organically modified layered clay mineral.

Thus, 0.2 part of trimethylolpropane triacrylate was added as a cross-linking agent per 100 parts of the monomer to the transparent dispersion added with an external action and dissolved uniformly. After applying this transparent adhesive composition to a thickness of 10 μm by an ink jet method, photopolymerization was performed by irradiating 900 mJ / cm ² of ultraviolet rays with a high-pressure mercury lamp having a light intensity of 5 mW / cm ^{2 in} a nitrogen gas atmosphere. An adhesive layer D was prepared.

The storage elastic modulus at 25 ° C. of the adhesive layer D was 1.6 × 10 ⁷ Pa.

(Adhesive layer E)
In the production of the adhesive layer D, an adhesive layer E was produced in the same manner except that 20 g of organic layered clay mineral, 80 g of butyl acrylate and 150 g of toluene as an organic solvent were used.

The storage elastic modulus at 25 ° C. of the adhesive layer E was 4.4 × 10 ⁶ Pa. (28% with respect to adhesive layer D)
(Adhesive layer F)
In the production of the adhesive layer D, an adhesive layer F was produced in the same manner except that 10 g of the organic layered clay mineral, 80 g of 2-ethylhexyl acrylate, and 150 g of toluene as the organic solvent were used.

The storage elastic modulus at 25 ° C. of the adhesive layer F was 7.0 × 10 ⁵ Pa. (4% with respect to adhesive layer D)
(Adhesive layer G)
<Preparation of adhesive layer>
As a cationically polymerizable compound, bisphenol A type epoxy resin (trade name “Epicoat 828” manufactured by Yuka Shell Epoxy Co., Ltd., 50 parts by mass, functional group equivalent = 190 g-resin / mol), bisphenol A type epoxy resin (Oyka Shell Epoxy Co., Ltd.) Product name “Epicoat 1001”, functional group equivalent = 475 g-regin / mol) 10 parts by mass, polyester resin (trade name “Eritel UE3400” manufactured by Unitika) as polymer, 70 parts by mass, aromatic photocation polymerization initiator 1 part by mass of a sulfonium salt (trade name “Adekaoptomer SP170” manufactured by Asahi Denka Co., Ltd.) is fed into the flask, and 100 parts by weight of methyl ethyl ketone as an organic solvent is added to the flask. (Product name "Homo Disper L type" manufactured by Special Machine Engineering Co., Ltd. To prepare a post-curing pressure-sensitive adhesive composition was uniformly stirred and mixed at a stirring speed 3000rpm using.

After the prepared post-curing adhesive composition was applied at a thickness of 10 μm by an inkjet method, it was irradiated with UV light of 900 mJ / cm ² with a high-pressure mercury lamp having a light intensity of 5 mW / cm ^{2 in} a nitrogen gas atmosphere. And photopolymerized.

The storage elastic modulus at 25 ° C. of the adhesive layer G was 3.0 × 10 ⁸ Pa.

(Adhesive layer H)
As a cationically polymerizable compound, a bisphenol A type epoxy resin (trade name “Epicoat 828” manufactured by Yuka Shell Epoxy Co., Ltd., 20 parts by mass, functional group equivalent = 190 g-resin / mol), and a styrene-butadiene-styrene copolymer ( Asahi Kasei Co., Ltd. trade name “Tufprene A”) 20 parts by mass, and as the photocationic polymerization initiator, aromatic sulfonium salt (Asahi Denka Co., Ltd. trade name “Adekaoptomer SP170”) 1 part by mass was used. Similarly, an adhesive layer H was produced.

The storage elastic modulus at 25 ° C. of the adhesive layer H was 1.5 × 10 ⁶ Pa. (5% with respect to adhesive layer G)
(Adhesive layer I)
The main component (part number: EL-436A, manufactured by Toyo Morton Co., Ltd.) and a curing agent (part number: EL-436B, manufactured by Toyo Morton Co., Ltd.) of a two-component water-based urethane adhesive are blended at 10: 3, and 10 with ion-exchanged water. A pressure-sensitive adhesive composition was prepared by diluting to a mass%, and applied at a thickness of 10 μm by an ink jet method.

The storage elastic modulus of the adhesive layer I at 25 ° C. was 8.0 × 10 ⁶ Pa.

(Adhesive layer J)
The main component of water-based acrylic adhesive (product name: Dick Dry WS-201A, manufactured by Dainippon Ink & Chemicals, Inc.) and a curing agent (product name: Dick Dry LJ55, manufactured by Dainippon Ink & Chemicals, Inc.) are blended at 10: 3. A pressure-sensitive adhesive layer J was prepared in the same manner as the pressure-sensitive adhesive layer I except that it was diluted to 10% by mass with ion-exchanged water.

The storage elastic modulus at 25 ° C. of the adhesive layer J was 9.0 × 10 ⁵ Pa. (11% relative to adhesive layer I)
(Adhesive layer K)
The main component (part number: TM-225A, manufactured by Toyo Morton Co., Ltd.) and a curing agent (part number: TM-225B, manufactured by Toyo Morton Co., Ltd.) of a two-pack type solvent-based urethane adhesive are blended in a ratio of 1: 1. An adhesive layer K was produced in the same manner as the adhesive layer I, except that it was diluted to mass%.

The storage elastic modulus at 25 ° C. of the adhesive layer K was 3.0 × 10 ⁷ Pa.

(Adhesive layer L)
The main component (part number: TM-225A, manufactured by Toyo Morton Co., Ltd.) and a curing agent (part number: TM-225B, manufactured by Toyo Morton Co., Ltd.) of 100 parts are blended in 100: 1, and 10 parts by ethyl acetate. An adhesive layer L was prepared in the same manner as the adhesive layer I, except that it was diluted to mass%.

The storage elastic modulus at 25 ° C. of the adhesive layer L was 7.0 × 10 ⁴ Pa. (0.2% of adhesive layer K)
(Adhesive layer M)
In the production of the adhesive layer D, an adhesive layer F was produced in the same manner except that 20 g of the organically modified layered clay mineral, 80 g of 2-ethylhexyl acrylate, 150 g of toluene as the photopolymerization initiator and the organic solvent were used.

The storage elastic modulus at 25 ° C. of the adhesive layer M was 9.4 × 10 ⁶ Pa.

<Production of liquid crystal display device>
A liquid crystal panel for viewing angle measurement was produced as follows, and the characteristics as a liquid crystal display device were evaluated.

  The polarizing plates on both sides of the commercially available 32 type liquid crystal TV (MVA type liquid crystal cell, using a direct type backlight) that had been bonded in advance were carefully peeled off. 1-8 were each bonded to the glass surface of a liquid crystal cell.

  At that time, the polarizing plate is bonded so that the phase difference film side is the liquid crystal cell side and the absorption axis is directed in the same direction as the polarizing plate bonded in advance. Device No. 1 to 8 were produced.

  After the produced liquid crystal display device was stored at 60 ° C. and 90% RH for 1500 hours, the liquid crystal display device was turned on, and after 6 hours, the presence or absence of light leakage in the black display was confirmed. Evaluation was performed according to the following criteria, and the results are shown in Table 2.

  A: No light leakage in the vicinity is observed.

  ○: Light leakage in the surrounding area is hardly an issue.

  Δ: Peripheral light leakage is observed.

  ×: Significant light leakage around

  From the above table, it was found that the liquid crystal display devices 1 to 5 using the polarizing plate of the present invention were remarkably improved in peripheral light leakage.

Example 2
A polarizing plate was prepared in the same manner except that the following cyclic olefin resin film was used instead of Konica Milnotac KC8UCR4 (retardation film) of Example 1, and then liquid crystal display devices 9 to 13 (present invention) 14 -16 (comparative example) was produced.

<< Production of Cyclic Olefin Resin Film >>
In a nitrogen atmosphere, 500 parts of dehydrated cyclohexane, 1.2 parts of 1-hexene, 0.15 part of dibutyl ether, and 0.30 part of triisobutylaluminum were mixed in a reactor at room temperature, and then kept at 45 ° C. 20 parts of tricyclo [4.3.0.12,5] deca-3,7-diene (dicyclopentadiene, hereinafter abbreviated as DCP), 1,4-methano-1,4,4a, 9a-tetrahydrofluorene ( Hereinafter, a norbornene-based monomer comprising 140 parts of MTF) and 40 parts of 8-methyl-tetracyclo [4.4.0.12, 5.17,10] -dodec-3-ene (hereinafter abbreviated as MTD). The mixture and 40 parts of tungsten hexachloride (0.7% toluene solution) were continuously added over 2 hours for polymerization. To the polymerization solution, 1.06 part of butyl glycidyl ether and 0.52 part of isopropyl alcohol were added to deactivate the polymerization catalyst and stop the polymerization reaction.

  Next, 270 parts of cyclohexane is added to 100 parts of the reaction solution containing the obtained ring-opening polymer, and 5 parts of a nickel-alumina catalyst (manufactured by JGC Chemical Co., Ltd.) is added as a hydrogenation catalyst, and the pressure is increased to 5 MPa with hydrogen. The mixture was heated to 200 ° C. while being pressurized and stirred, and then reacted for 4 hours to obtain a reaction solution containing 20% of a DCP / MTF / MTD ring-opening polymer hydrogenated polymer. After removing the hydrogenation catalyst by filtration, a soft polymer (manufactured by Kuraray; Septon 2002) and an antioxidant (manufactured by Ciba Specialty Chemicals; Irganox 1010) are added and dissolved in the resulting solutions. (Both 0.1 parts per 100 parts polymer). Next, cyclohexane and other volatile components, which are solvents, are removed from the solution using a cylindrical concentration dryer (manufactured by Hitachi, Ltd.), and the hydrogenated polymer is extruded in the form of a strand from the extruder in a molten state, and after cooling, pellets And recovered. When the copolymerization ratio of each norbornene monomer in the polymer was calculated from the composition of residual norbornenes in the solution after polymerization (by gas chromatography method), it was almost charged at DCP / MTF / MTD = 10/70/20. It was equal to the composition. This hydrogenated ring-opened polymer had a weight average molecular weight (Mw) of 31,000, a molecular weight distribution (Mw / Mn) of 2.5, a hydrogenation rate of 99.9%, and a Tg of 134 ° C.

  The obtained pellets of the ring-opened polymer hydrogenated product were dried at 70 ° C. for 2 hours using a hot air dryer in which air was circulated to remove moisture. Next, the pellets were subjected to a short shaft extruder having a coat hanger type T die having a lip width of 1.5 m (manufactured by Mitsubishi Heavy Industries, Ltd .: screw diameter 90 mm, T die lip material was tungsten carbide, peel strength from molten resin 44 N ) To produce a cycloolefin polymer film having a thickness of 80 μm and a slit width of 1.4 m. Extrusion molding was performed in a clean room of class 10,000 or less under molding conditions of a molten resin temperature of 240 ° C. and a T die temperature of 240 ° C. During the drying process, the obtained film was stretched 1.50 times in the width direction at a stretching temperature of 155 ° C. using a tenter device, and a cycloolefin polymer film having retardation values of Ro45 nm and Rt of 130 nm was obtained by the following measurement. It was. At that time, as a result of adjusting the length of the tenter device, the clip interval, and the tension of the clip, the orientation angle deviation between the in-plane slow axis of the film and the width direction of the film was within ± 0.4 °.

(Ro, Rt, measuring method in the slow axis direction)
The average refractive index of the film constituting material was measured using an Abbe refractometer (4T). Moreover, the thickness of the film was measured using a commercially available micrometer.

  Using an automatic birefringence meter KOBRA-21ADH (manufactured by Oji Scientific Instruments), film retardation measurement at a wavelength of 590 nm was performed under the same environment for 24 hours in an environment of 23 ° C. and 55% RH. went. The above-mentioned average refractive index and film thickness were input into the following formula, and values of in-plane retardation (Ro) and retardation in the thickness direction (Rt) were obtained. The direction of the slow axis was also measured at the same time to measure the orientation angle deviation.

Ro = (Nx−Ny) × d
Rt = ((Nx + Ny) / 2−Nz) × d
(In the formula, Nx, Ny, and Nz represent the refractive indexes in the principal axis x, y, and z directions of the refractive index ellipsoid, respectively, and Nx and Ny represent the refractive index in the film in-plane direction, and Nz represents the thickness direction of the film. In addition, Nx ≧ Ny, and d represents the film thickness (nm).
When the produced liquid crystal display device was evaluated for peripheral light leakage in the same manner as in Example 1, Example 1 was reproduced, and the liquid crystal display devices 14 to 16 using comparative polarizing plates were evaluated as Δ. It was found that the liquid crystal display devices 9 to 13 using the polarizing plate of the present invention were markedly improved because the peripheral light leakage was remarkably improved.

Example 3
As the polarizing plate protective film of Example 1, Konica Minol Tuck KC8UXW-H (polarizing plate protective film with hard coat) was changed to Konica Minol Tack KC8UXW-RHA (polarizing plate protective film with antireflection processed hard coat). Polarizing plates were produced in the same manner as in Example 1, and polarizing plates 17 to 21 of the present invention and comparative polarizing plates 22 to 24 were produced.

  As a result of evaluation in the same manner as in Example 1, no light leakage was observed in the polarizing plate of the present invention, whereas light leakage was significant in the comparative polarizing plate.

It is a schematic diagram which shows the various patterns of the adhesion layer which concerns on this invention. It is sectional drawing which shows an example of the inkjet head which can be used for the inkjet method which concerns on this invention. It is the schematic which shows an example of the inkjet head part and nozzle plate which can be used by this invention. It is the schematic which shows the formation pattern of the adhesion layer used in the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Polarizing plate 10 Inkjet head 12 Piezoelectric element 31 Ink droplet

Claims (9)

A polarizing plate having a polarizing plate protective film, a polarizer, a retardation film, and an adhesive layer, wherein the polarizing plate has an adhesive layer having a different storage elastic modulus within the plane of one polarizing plate. The polarizing plate according to claim 1, further comprising an adhesive layer in which a storage elastic modulus of an edge portion of the polarizing plate is lower than a storage elastic modulus in the vicinity of a central portion. The polarizing plate according to claim 1 or 2, further comprising an adhesive layer having a storage elastic modulus of the edge portion of 80% or less with respect to a storage elastic modulus in the vicinity of the center portion. The polarizing plate according to claim 1, wherein the retardation film contains a cyclic olefin resin or a cellulose derivative. A method for producing a polarizing plate, comprising: adhering a component constituting at least one adhesive layer to an adhesive layer forming surface to form an adhesive layer having different adhesiveness in one polarizing plate. Production of a polarizing plate characterized by forming a pressure-sensitive adhesive layer having different adhesive properties in a single polarizing plate by adhering droplets containing at least one type of pressure-sensitive adhesive layer to an adhesive layer-forming surface Method. The method for producing a polarizing plate according to claim 6, wherein the means for attaching the droplets to the adhesive layer forming surface is an inkjet method. A polarizing plate having a polarizing plate protective film, a polarizer and a retardation film, having an adhesive layer between the polarizer and the liquid crystal cell, and having a storage elastic modulus of the adhesive layer of one sheet A display device characterized by being different in the plane. The display device according to claim 8, wherein the adhesive layer is an adhesive layer in which a storage elastic modulus of an edge portion is lower than that in a vicinity of a central portion.

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