JPWO2012035837A1 - Optical display device manufacturing system and method - Google Patents

Abstract

This invention makes it a subject to provide the manufacturing system and manufacturing method which can form an optical display apparatus with a high yield using a polarizing plate elongate roll.
The optical display device manufacturing system of the present invention is an optical display device manufacturing system formed by laminating and cutting a polarizing plate contained in a long polarizing plate roll (R1, R2) to an optical display unit (W). The polarizing plate long roll (R1, R2) is wound at least in the form of a long sheet having a width corresponding to the short side or the long side of the optical display unit (W). And is composed of at least a first bonding / cutting device (4, 5), a second bonding / cutting device (14, 15), and a failure location discharging device (6, 16). It is characterized by that.

Description

  The present invention relates to a manufacturing system and a manufacturing method of an optical display device formed by bonding and cutting a polarizing plate included in a long polarizing plate roll to an optical display unit.

  In recent years, a long roll slitting a polarizing plate into a panel size is manufactured, and an optical display device manufacturing system that cuts and bonds to a panel size just before being bonded to a liquid crystal panel (display unit) in-line. A manufacturing system of an optical display device has been proposed in which a long roll is cut and bonded directly to a panel with the release sheet remaining, and then the release sheet is peeled off (for example, Patent Document 1). ~ 4).

  In the optical display device manufacturing system of the above method, since the polarizing plate is stored in a roll shape and cut immediately before use, the curling of the polarizing plate becomes strong and fails when pasted to the display unit. There is a problem that the yield is lowered, such as increase in the number.

  In order to solve this problem, measures have been taken to strengthen the suction of the suction device when the roll-shaped polarizing plate is chip-cut and then sucked and transported. The problem is occurring.

  In addition, when using a so-called single protective film polarizing plate provided with a protective film only on one surface of the polarizing film, the polarizing plate curls very strongly, and the polarizing plate is cut and then pasted to the display unit. There is a problem that cannot be used.

JP 2010-113357 A JP 2009-276755 A Japanese Patent No. 4451924 Japanese Patent No. 4307510

  The present invention has been made in view of the above problems and situations, and a solution to that problem is a manufacturing system and a manufacturing method capable of forming an optical display device with a high yield using a polarizing plate long roll. Is to provide.

  The above-mentioned problem according to the present invention is solved by the following means.

1. A manufacturing system of an optical display device formed by laminating and cutting a polarizing plate included in a polarizing plate long roll on an optical display unit, wherein the polarizing plate long roll is a short side of the optical display unit or It consists of an optical film provided with at least a polarizing plate and an adhesive layer, wound up into a long sheet having a width corresponding to the long side, and at least the following first bonding cutting device, second bonding cutting device, and An optical display device manufacturing system comprising a failure location discharging device.
(1) First bonding / cutting device: a long polarizing plate roll (referred to as a “first long roll”) wound into a long sheet having a width corresponding to the short side of the optical display unit. An apparatus that pulls out a sheet-like product, performs in-line inspection, and bonds it to one surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(2) Second bonding / cutting device: long from a polarizing plate long roll (referred to as “second long roll”) wound into a long sheet having a width corresponding to the long side of the optical display unit. A device that pulls out a sheet-like product, performs in-line inspection, and bonds it to the other surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(3) Failure location discharge device: A device that cuts and removes the failure location found by in-line inspection of the long sheet product.

  2. 2. The optical device according to claim 1, wherein the failure location discharging device has a function of cutting and removing by changing the length of the long side or the length of the short side according to the width of the failure location. Display device manufacturing system.

3. A method of manufacturing an optical display device formed by laminating and cutting a polarizing plate contained in a polarizing plate long roll on an optical display unit, wherein the polarizing plate long roll is a short side of the optical display unit or It consists of an optical film provided with at least a polarizing plate and an adhesive layer, wound into a long sheet having a width corresponding to the long side, and at least the following first bonding cutting step, second bonding cutting step, and A method of manufacturing an optical display device comprising a failure location discharging step.
(1) 1st bonding cutting process: It is long from the polarizing plate long roll (it is called "1st long roll") wound up by the long sheet form of the width | variety corresponding to the short side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the sheet-like product to one surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(2) 2nd bonding cutting process: It is long from the polarizing plate elongate roll (it is called "2nd elongate roll") wound up by the elongate sheet form of the width | variety corresponding to the long side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the other product to the other surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(3) Failure location discharging step: A step of cutting and removing the failure location found by in-line inspection of the long sheet product.

  By the above means of the present invention, it is possible to provide a manufacturing system and a manufacturing method capable of forming an optical display device with a high yield using a long polarizing plate roll.

The flowchart which shows the process by the manufacturing system of the optical display apparatus of this invention. The conceptual diagram which shows the whole process by the manufacturing system of the optical display apparatus of this invention (A) Side view conceptual diagram of the whole manufacturing system of the optical display device of the present invention, (b) Side view conceptual diagram in the case of using a failure location discharging device in the first bonding / cutting step Schematic diagram of failure location discharging apparatus and failure location according to the present invention Cross section and plan view of failure location discharge apparatus according to the present invention

  An optical display device manufacturing system according to the present invention is an optical display device manufacturing system formed by laminating and cutting a polarizing plate contained in a polarizing plate long roll to an optical display unit, the polarizing plate long The roll is made of an optical film having at least a polarizing plate and an adhesive layer wound into a long sheet having a width corresponding to the short side or the long side of the optical display unit, and at least the first bonding. It is comprised by the cutting device, the 2nd bonding cutting device, and the failure location discharge device, It is characterized by the above-mentioned. This feature is a technical feature common to the inventions according to claims 1 to 3.

  As an embodiment of the present invention, from the viewpoint of manifesting the effect of the present invention, the failure location discharging device cuts and removes by changing the length of the long side or the length of the short side according to the width of the failure location. It is preferable to have a function that can be performed.

  Further, the method for producing an optical display device of the present invention is a method for producing an optical display device formed by bonding and cutting a polarizing plate contained in a long polarizing plate roll to an optical display unit, the polarizing plate The long roll is made of an optical film having at least a polarizing plate and an adhesive layer wound in a long sheet shape having a width corresponding to the short side or the long side of the optical display unit, and at least the first It is comprised by the bonding cutting process, the 2nd bonding cutting process, and a failure location discharge process.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

(Outline of optical display device manufacturing system and method)
An optical display device manufacturing system according to the present invention is an optical display device manufacturing system formed by laminating and cutting a polarizing plate contained in a polarizing plate long roll to an optical display unit, the polarizing plate long The roll is made of an optical film having at least a polarizing plate and an adhesive layer wound in a long sheet shape having a width corresponding to the short side or the long side of the optical display unit, and at least the following first bonding It is comprised by the cutting device, the 2nd bonding cutting device, and the failure location discharge device, It is characterized by the above-mentioned.
(1) First bonding / cutting device: a long polarizing plate roll (referred to as a “first long roll”) wound into a long sheet having a width corresponding to the short side of the optical display unit. An apparatus that pulls out a sheet-like product, performs in-line inspection, and bonds it to one surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(2) Second bonding / cutting device: long from a polarizing plate long roll (referred to as “second long roll”) wound into a long sheet having a width corresponding to the long side of the optical display unit. A device that pulls out a sheet-like product, performs in-line inspection, and bonds it to the other surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(3) Failure location discharge device: A device that cuts and removes the failure location found by in-line inspection of the long sheet product.

  In addition, it is preferable that the said failure part discharge apparatus has a function which can cut and remove by changing the length of the long side or the length of the short side according to the width of the failure part.

The method for producing an optical display device of the present invention is a method for producing an optical display device formed by laminating and cutting a polarizing plate contained in a long polarizing plate roll on an optical display unit, the polarizing plate long The roll is made of an optical film having at least a polarizing plate and an adhesive layer wound in a long sheet shape having a width corresponding to the short side or the long side of the optical display unit, and at least the following first bonding It is characterized by comprising a cutting step, a second bonding cutting step, and a failure location discharging step.
(1) 1st bonding cutting process: It is long from the polarizing plate long roll (it is called "1st long roll") wound up by the long sheet form of the width | variety corresponding to the short side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the sheet-like product to one surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(2) 2nd bonding cutting process: It is long from the polarizing plate elongate roll (it is called "2nd elongate roll") wound up by the elongate sheet form of the width | variety corresponding to the long side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the other product to the other surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(3) Failure location discharge device: A process of cutting and removing the failure location found by in-line inspection of the long sheet product.

  Hereinafter, embodiments of the manufacturing system and the manufacturing method will be described with reference to the drawings illustrating examples thereof as appropriate. FIG. 1 is a flowchart showing the steps of the optical display device manufacturing system of the present invention. FIG. 2 is a conceptual diagram showing the entire process by the optical display device manufacturing system of the present invention. FIG. 3A is a side view conceptual diagram of the entire process of the optical display device manufacturing system of the present invention, and FIG. FIG. FIG. 4 is a conceptual diagram of the failure location discharging apparatus and the failure location according to the present invention. FIG. 5 is a cross-sectional view and a plan view of the failure location discharging apparatus according to the present invention.

(Outline of polarizing plate long roll)
The “polarizing plate long roll” according to the present invention is a configuration in which an optical film provided with a polarizing plate and an adhesive layer are laminated, and is a long sheet having a width corresponding to the short side or the long side of the optical display unit. It is the one wound up by That is, it is characterized by having a configuration in which a polarizing film and at least an optical film and an adhesive layer are provided in this order on one side of the polarizing film.

  The optical film according to the present invention may be a single layer or a laminate, and any optical film having optical anisotropy therein may be used. Moreover, as an optical film provided with the polarizing plate, the optical film etc. which laminated | stacked two or more combinations of the retardation film, the polarizing plate protective film, the brightness improvement film, and these films on the polarizing plate are illustrated.

  In addition, it is required to provide an adhesive layer on one surface of the optical film so that the optical film can be attached to the optical display unit. Moreover, you may provide the release film for protecting this adhesion layer.

  The present invention is effective when two rolls having the same optical anisotropy are used, and in particular, two rolls having the same absorption axis of the polarizing plate constituting the optical film are used. It is effective when The direction of the absorption axis of the polarizing plate is usually the long direction of the roll. Further, in the case of a retardation film, there are those in which the slow axis coincides with the long direction of the roll original fabric, those in which the slow axis is vertical, and those in which the slow axis is in an oblique direction with a constant angle.

  In the present application, an optical film in which a polarizing plate protective film, a brightness enhancement film, a release film and the like are laminated may be referred to as a sheet product. Moreover, what was cut | disconnected by the square of the predetermined dimension from the polarizing plate elongate roll may be called "sheet-like polarizing plate."

(Polarizing film)
In the present application, “polarizing film (also referred to as“ polarizer ”)” refers to a film (film) having a function of transmitting only linearly polarized light having a specific vibration direction.

  Any appropriate polarizing film can be adopted as the polarizing film depending on the purpose. For example, dichroic substances such as iodine and dichroic dyes on hydrophilic polymer films such as polyvinyl alcohol (PVA) film, partially formalized polyvinyl alcohol film, and ethylene / vinyl acetate copolymer partially saponified film. And a polyene-based oriented film such as a uniaxially stretched product and a dehydrated product of polyvinyl alcohol and a dehydrochlorinated product of polyvinyl chloride. Among these, a polarizing film uniaxially stretched by adsorbing a dichroic substance such as iodine on a polyvinyl alcohol film is particularly preferable because of its high polarization dichroic ratio. The thickness of these polarizing films is not particularly limited, but is preferably about 5 to 80 μm.

  A polarizing film uniaxially stretched by adsorbing iodine to a polyvinyl alcohol film can be produced, for example, by dyeing polyvinyl alcohol in an iodine aqueous solution and stretching it 3 to 7 times the original length. . If necessary, it may contain boric acid, zinc sulfate, zinc chloride, or the like, or may be immersed in an aqueous solution such as potassium iodide. Further, if necessary, the polyvinyl alcohol film may be immersed in water and washed before dyeing.

  By washing the polyvinyl alcohol film with water, not only can the surface of the polyvinyl alcohol film be cleaned and the anti-blocking agent can be washed, but also the effect of preventing unevenness such as uneven dyeing by swelling the polyvinyl alcohol film. There is also. Stretching may be performed after dyeing with iodine, may be performed while dyeing, or may be dyed with iodine after stretching. The film can be stretched in an aqueous solution of boric acid or potassium iodide or in a water bath.

(Polarizing film protective film)
The “polarizing film protective film” is a constituent member of a polarizing plate and refers to a film that is bonded to the polarizing film and plays a role of suppressing dimensional changes and physical property changes of the polarizing film. For example, a resin film such as a triacetyl cellulose (TAC) film is generally used. Details of the resin base material that can be used in the present invention will be described later.

  In addition, as a polarizing film protective film, for example, a commercially available optical film (for example, Konica Minoltack KC8UX, KC6UA, KC4UA, KC8UY, KC4UY, KC4KR, KC4CZ, KC4FR, KC4HR, KC8UY-HA, KC4UA Etc.) are also preferably used.

(Polarizer)
In the present application, the “polarizing plate” is a state in which a polarizing film protective film is laminated on at least one side of the polarizing film, or an adhesive layer for bonding to a liquid crystal cell or other optical member on one side. It means the state where is provided. In some cases, it may be used to include a roll-shaped polarizing plate or a sheet-shaped polarizing plate.

  The polarizing plate of the present invention can be produced by a general method. It is preferable to provide an adhesive layer or an adhesive layer on the back surface side of the polarizing film protective film, and bond it to at least one surface of the polarizing film produced by the above-described method.

  When the polarizing film protective film according to the present invention is bonded to the polarizing film, it is preferable to perform a hydrophilic treatment on the surface of the film before that. Examples of the hydrophilic treatment include saponification treatment, plasma treatment, corona treatment, flame treatment, and ultraviolet irradiation treatment. The saponification treatment includes acid saponification treatment and alkali saponification treatment. In the present invention, alkali saponification treatment is preferably used.

  The alkali saponification treatment is preferably carried out by a method of directly immersing the film in a saponification solution tank or a method of applying a saponification solution to a cellulose acylate film. Examples of the coating method include a dip coating method, a curtain coating method, an extrusion coating method, a bar coating method, and an E-type coating method. The solvent of the alkali saponification coating solution has good wettability because it is applied to the transparent support of the saponification solution. It is preferred to select a solvent that remains good. Specifically, an alcohol solvent is preferable, and isopropyl alcohol is particularly preferable. An aqueous solution of a surfactant can also be used as a solvent. The alkali of the alkali saponification coating solution is preferably an alkali that dissolves in the above solvent, and more preferably KOH or NaOH. The pH of the saponification coating solution is preferably 10 or more, and more preferably 12 or more. The reaction conditions at the time of alkali saponification are preferably 1 second to 5 minutes at room temperature, more preferably 5 seconds to 5 minutes, and particularly preferably 20 seconds to 3 minutes. After the alkali saponification reaction, it is preferable to wash the surface to which the saponification solution is applied with water or with an acid and then with water.

In addition, as an adhesive used for the said adhesive layer, the adhesive whose storage elastic modulus in 25 degreeC is the range of 1.0 * 10 < ⁴ > -1.0 * 10 < ⁹ > Pa in at least one part of an adhesive layer is used. Preferably, 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 types and oxidized polyether methacrylates, cyanoacrylate-based instantaneous pressure-sensitive adhesives, and acrylate-peroxide-based two-pack type instantaneous pressure-sensitive adhesives.

  The pressure-sensitive adhesive may be a one-component type or a type in which two or more components are mixed before use.

  The pressure-sensitive adhesive may be a solvent system using an organic solvent as a medium, or may be 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 solventless type. The density | concentration of the said adhesive liquid should just be suitably determined with the film thickness after adhesion, the coating method, the coating conditions, etc., and is 0.1-50 mass% normally.

  In the present invention, the performance can be improved by processing the film surface before bonding to the polarizing film according to the individual required characteristics of the polarizing film protective film. Examples of such surface treatment include anti-glare treatment, non-glare treatment or anti-reflection treatment as treatment for preventing surface reflection and improving the visibility of the liquid crystal panel; anti-static treatment or anti-contamination treatment for reducing surface dirt adhesion; Hard coat treatment that improves mechanical properties, increases surface hardness, and improves solvent resistance and chemical resistance; coloring treatment for imparting a desired hue, and the like. These treatments can be performed by a known method according to the purpose. Several types of surface treatments may be carried out in a superimposed manner.

  In addition, you may provide the polarizing plate protective film which can peel in the polarizing plate which concerns on this invention. The term “peelable polarizing plate protective film” as used herein refers to a film for protecting the polarizing plate comprising the polarizing film and the polarizing film protective film, and at least in order to facilitate the peeling of the adhesive layer described later. The film which peeled was given to the surface of the side far from the polarizing film of a polarizing film protective film.

  A conventionally well-known method can be employ | adopted as a method of providing peelability to the surface of the polarizing plate protective film far from the polarizing film. For example, a method of providing a peelable layer is preferable.

  The peelability-imparting layer can be formed of any appropriate release agent. Specific examples include silicone-based release agents such as condensation-type and addition-type thermosetting silicone release agents, radiation-curable silicone release agents such as ultraviolet rays and electron beams, etc .; fluorine-containing esters of (meth) acrylic acid; Fluorine release agent containing an acrylic copolymer obtained by polymerizing an alkyl ester of (meth) acrylic acid having an alkyl group having 8 or less carbon atoms; having a long-chain alkyl group having 12 to 22 carbon atoms A long-chain alkyl release agent comprising an acrylic copolymer obtained by polymerizing an alkyl ester of (meth) acrylic acid and an alkyl ester of (meth) acrylic acid having an alkyl group having 8 or less carbon atoms ( JP-B-29-3144, JP-B-29-7333) and the like. Among these, a silicone release agent is preferable. As the peelability-imparting layer, for example, a release layer described in JP-A-2004-346093 may be employed.

  Various functional layers such as a hard coat treatment layer, an antireflection treatment layer, an anti-sticking treatment layer, and an antiglare treatment layer may be provided between the peelable layer and the base film according to the purpose.

  Moreover, it is preferable to give weak adhesiveness to the surface of the peelable polarizing plate protective film near the polarizing film.

(Adhesive layer)
In the long polarizing plate roll of the present invention, an adhesive layer (also referred to as “adhesive layer” or “adhesive layer”) can be provided between various members constituting the roll.

  The pressure-sensitive adhesive layer can be formed of any appropriate pressure-sensitive adhesive. Specific examples include acrylic pressure-sensitive adhesives containing (meth) acrylic polymers. As a monomer which comprises a (meth) acrylic-type polymer, (meth) acrylic-acid alkylester is mentioned, for example. Specific examples of the (meth) acrylic acid alkyl ester include butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, Examples thereof include isononyl (meth) acrylate, allyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and the like.

  The (meth) acrylic polymer is preferably obtained by copolymerizing the above (meth) acrylic acid alkyl ester and a hydroxyl group-containing monomer. Specific examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6-hydroxy (meth) acrylate. Hydroxyalkyl (meth) acrylates such as hexyl, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) -methyl acrylate , (Meth) acrylic acid polyethylene glycol, (meth) acrylic acid polypropylene glycol and the like.

  Any suitable polymerization initiator may be used when the (meth) acrylic polymer is polymerized. Specific examples of the polymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-dimethylacetophenone, methoxyacetophenone, 2,2-dimethoxy- Acetophenone-based photopolymerization initiators such as 2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) -phenyl] -2-morpholinopropane-1 Etc.

  In the polymerization, a crosslinking agent may be added. As a crosslinking agent, polyfunctional (meth) acrylate is mentioned, for example. Specific examples of polyfunctional (meth) acrylates include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate , Pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) ) Acrylate and the like.

  The thickness of the said adhesion layer becomes like this. Preferably it is 5-1000 micrometers, More preferably, it is 10-100 micrometers.

  In addition, as the said adhesion layer, you may employ | adopt the glass crack prevention adhesion layer of Unexamined-Japanese-Patent No. 2005-173462, for example.

(First long roll and second long roll)
FIG. 2 shows the entire process by the optical display device manufacturing system, which is a typical example of the embodiment of the present invention. In this embodiment, as shown in FIG. 2, the 1st bonding cutting apparatus M1 is the supply apparatus 1 of the optical display unit W, the conveying apparatus 2 of the 1st elongate roll F1, the in-line inspection apparatus 3, and the 1st. The 1st bonding apparatus 4 which bonds 1 long roll F1, the cutting device 5, the failure location discharge apparatus 6, and the conveyance supply apparatus 7 which conveys and supplies the optical display unit W after bonding and cutting | disconnection are provided. I have.

  On the other hand, the 2nd bonding cutting apparatus M2 is the conveying apparatus 12 of the 2nd long roll F2, the inline inspection apparatus 13, the 2nd bonding apparatus 14 which bonds the 2nd long roll F2, and the cutting apparatus 15. The failure location discharging device 16 and the transport device 17 for transporting the optical display device WA formed after bonding and cutting are provided.

  In the embodiment, as shown in FIG. 2, the transport device 2 of the first long roll F1, the first bonding device 4, the transport supply device 7, and the transport device 12 of the second long roll F2, As the 2nd bonding apparatus 14 is arrange | positioned as FIG. 2 shows, with respect to the panel flow direction of the 1st bonding apparatus 4, the optical display unit W is supplied from a perpendicular | vertical direction, The example by which the supply apparatus 1 is arrange | positioned is shown.

  As shown in FIGS. 2 and 3, the first long roll and the second long roll according to the present invention are each a polarizing plate that is cut into a predetermined length and bonded to both sides of the optical display unit. It is a long roll.

  The first long roll R1 is wound in a state where the polarizing plate long roll (long sheet product) F1 is slit in a width corresponding to the short side of the optical display unit parallel to the absorption axis of the polarizing plate. It has been turned. The long sheet-like product may be wound alone, but is preferably wound around a core material such as a core tube.

  The second long roll R2 has a polarizing plate long roll (long sheet product) F2 slit in a width corresponding to the long side of the optical display unit parallel to the absorption axis of the polarizing plate. It is wound. The long sheet-like product may be wound alone, but is preferably wound around a core material such as a core tube.

  In the present invention, “corresponding to the long side or short side of the optical display unit” means that a polarizing plate long roll (long sheet product) corresponding to the long side or short side length of the optical display unit is attached. Refers to the combined length (excluding the exposed portion), and the length of the long side or short side of the optical display unit and the width of the polarizing plate long roll (long sheet product) need not be the same. . In the present application, the case where the lengths of the long side and the short side are the same is included in the present invention.

  In the present invention, both the first long roll R1 and the second long roll R2 are slit-processed in parallel to the absorption axis of the polarizing plate constituting the first long roll R1 and have the absorption axis in the longitudinal direction of the roll. It is preferable. For this reason, the axial accuracy by bonding is improved, and the optical characteristics of the optical display device after bonding are improved. In particular, when an optical display unit is formed of a VA mode or IPS mode liquid crystal panel used in recent years for large TVs, the absorption axes of the polarizing plates of the first long roll and the second long roll can be made orthogonal. Therefore, it is only necessary to feed out the first and second rolls slitted in parallel to the absorption axis and cut them in the width direction, thereby increasing the production speed.

(Manufacturing method of a polarizing plate long roll original fabric)
The method for producing a polarizing plate long roll according to the present invention is a method for producing a roll that is cut into a predetermined length and bonded to the surface of an optical display unit, the optical film including a polarizing plate. And a pressure-sensitive adhesive layer are laminated in this order, and preferably, a long original fabric having a longitudinal direction parallel to the absorption axis of the polarizing plate is parallel to the longitudinal direction of the optical display unit. It includes a slitting process for cutting with a width corresponding to the side, and a winding process for winding the long sheet product obtained in the slitting process into a roll.

  The widths of the first long roll R1 and the second long roll R2 depend on the bonding size of the optical display unit. Specifically, the width of the first long roll R1 is determined corresponding to the short side of the optical display unit, and the width of the second long roll R2 is determined corresponding to the long side. For this reason, generally, the first long roll R1 and the second long roll R2 have different widths, and a predetermined width is obtained in advance by slit processing from a long slit polarizing plate long roll (long original fabric). A slit is used.

  There are a method of performing slit processing while rewinding the pre-slit polarizing plate long roll, and a method of performing without rewinding, both of which can be adopted. Moreover, in this invention, you may perform a slit process before the winding in the production line of a long sheet-like product.

  The manufacturing method of the polarizing plate long roll of the present invention is a manufacturing method of a polarizing plate long roll for cutting to a predetermined length and bonding it to the surface of the optical display unit. A slit process for cutting a long original fabric having a parallel longitudinal direction at a width corresponding to the short side or the long side of the optical display unit in parallel to the longitudinal direction, and a long sheet-like product obtained by the slit process And a winding step of winding in a roll shape.

  The details of the optical film according to the present invention will be described later.

(Optical display unit)
Examples of the optical display unit used in the present invention include a glass substrate unit of a liquid crystal cell and an organic EL light emitting unit. The present invention is effective for an optical display unit having a rectangular outer shape, and for example, one having a long side / short side of 16/9 or 4/3 is used. In addition, as an optical display unit, members, such as a long roll, may be previously laminated and integrated. The glass substrate unit of the liquid crystal cell is a liquid crystal cell in which liquid crystal is arranged between two transparent substrates so that voltage driving is possible, and at least one of the two transparent substrates is glass. This is what is a substrate.

(Liquid crystal display device)
By using the polarizing plate according to the present invention for a liquid crystal display device, the liquid crystal display device according to the present invention having various visibility can be manufactured.

  The polarizing plate according to the present invention can be used for liquid crystal display devices of various drive systems such as STN, TN, OCB, HAN, VA (MVA, PVA), IPS, OCB and the like. A VA (MVA, PVA) type liquid crystal display device is preferable.

  Even in the case of a large-screen liquid crystal display device having a screen size of 30 or more, a liquid crystal display device having excellent visibility such as uneven coloring and front contrast with little occurrence of unevenness due to environmental fluctuations and reduced light leakage is obtained. be able to.

(Manufacturing flowchart of optical display device)
The manufacturing method of the optical display apparatus of this invention is a manufacturing method of the optical display apparatus which bonded the elongate roll containing a polarizing plate to the optical display unit.

  Although the manufacturing method which concerns on this invention includes a 1st bonding cutting process and a 2nd bonding cutting process, any process may be performed previously and both processes may be performed simultaneously or substantially simultaneously.

  A 1st bonding cutting process is a length corresponding to the long side of the said optical display unit, after bonding a 1st long roll on the one surface of the said optical display unit using the 1st long roll mentioned above. It is to cut.

  A 2nd bonding cutting process uses the 2nd long roll mentioned above, After bonding a 2nd long roll on the other surface of the said optical display unit, the length corresponding to the short side of the said optical display unit It is to cut.

  More specifically, the manufacturing method of the optical display device of the present invention is, for example, the optical display while drawing and supplying the strip-shaped product from a roll around which the strip-shaped product having the first long roll is wound. A first long roll is bonded to one surface of the unit, and then a first bonding and cutting step for cutting to a predetermined length, and a roll is formed from a roll obtained by winding a belt-shaped sheet-like product having a second long roll. A second laminating and cutting step in which a second long roll is bonded to the other surface of the optical display unit while the sheet-like product is pulled out and supplied, and then cut into a predetermined length.

  A 1st bonding cutting process is fundamentally implemented by the conveyance process-cutting process described below, for example, and a 2nd bonding cutting process is implemented by the conveyance process-cutting process described below, for example.

(1) First polarizing plate long roll preparation step (FIG. 1, S1)
A long first sheet product is prepared as a first polarizing plate long roll as described below.

  Each of the following steps is preferably performed in an isolated structure isolated in a factory, and the cleanliness is preferably maintained. In particular, it is preferable that the cleanliness is maintained in the bonding step in which the long roll is bonded to the optical display unit.

(2) 1st conveyance process (FIG. 1, S2)
The first sheet product F1 is fed out from the first polarizing plate long roll prepared and installed, and is conveyed downstream. The first conveying device 2 that conveys the first sheet product F1 includes, for example, a nip roller pair, a tension roller, a rotation driving device, an accumulating device, a sensor device, a control device, and the like. Therefore, it is preferable to use a roll that is processed with silicon, fluorine resin, or the like so that the adhesive layer does not come into contact with the roll. The first roll is not used to transfer the adhesive layer, but may be used as part of the leader.

(3) First inspection process (FIG. 1, S3)
The first in-line inspection apparatus 3 is used to inspect the defects of the first sheet product F1. The defect inspection method here includes a method of photographing and processing images with transmitted light and reflected light on both sides of the first sheet product F1, and an inspection polarizing film between the CCD camera and the inspection object. A method of taking an image and processing an image by arranging it so as to be in crossed Nicols with the polarization axis of the polarizing plate as an object (sometimes referred to as “0 degree cross”), a polarizing film for inspection with a CCD camera and an inspection object Between the polarization axis of the polarizing plate to be inspected and a predetermined angle (for example, a range of greater than 0 ° and within 10 °) (sometimes referred to as “x degree cross”). There are methods for image capturing and image processing. Note that a known method can be applied to the image processing algorithm, and for example, a defect can be detected by density determination by binarization processing.

  In the image capturing / image processing method using transmitted light, foreign matter inside the first sheet product F1 can be detected. In the image photographing / image processing method using the reflected light, the adhered foreign matter on the surface of the first sheet product F1 can be detected. In the image photographing / image processing method using the 0-degree cross, mainly surface foreign matter, dirt, internal foreign matter, etc. can be detected as bright spots. In the image photographing / image processing method using the x-degree cross, a nick can be mainly detected.

  The defect information obtained by the first in-line inspection device 3 is linked with the position information (for example, position coordinates), transmitted to the control device, and cut by the failure location discharging device and the first cutting device 5 described later. Can contribute to the method.

(4) 1st long roll bonding process (FIG. 1, S4)
The first long roll F1 is bonded to the optical display unit W via the adhesive layer. At the time of bonding, the first long roll F1 and the optical display unit W are sandwiched between a pair of rolls and the like, and are crimped.

  In the present invention, since the first long roll F1 is bonded to the optical display unit W before cutting, the problem of curling of the polarizing plate can be solved.

(5) First cutting step (FIG. 1, S5)
The first cutting device 5 cuts the first long roll F1 into a predetermined size.

  In addition, when the 1st elongate roll F1 is equipped with the polarizing plate protective film which can be peeled, the layer except the said polarizing plate protective film is cut | disconnected. Regarding the cutting length, since the width of the first polarizing plate long roll corresponds to the short side, the long roll is cut at a length corresponding to the long side.

  In the present embodiment, as shown in FIG. 2, an example in which the width of the first polarizing plate long roll (first sheet product F1) corresponds to the short side of the optical display unit W is shown.

  Examples of the cutting means include a laser device, a cutter, and other known cutting means.

(6) Fault location discharge process (Fig. 1, S6)
Based on the defect information obtained by the first in-line inspection apparatus 3, it is configured to avoid the defects and cut so as not to include the defects in the region bonded to the optical display unit W. Thereby, the yield of the first sheet product F1 is greatly improved. As described above, a method of cutting while avoiding defects so as not to include defects in the region bonded to the optical display unit W is referred to as skip cut. However, defect information at the time of cutting is obtained by an in-line inspection apparatus. Or may be previously attached to a long polarizing plate roll. The first sheet product F1 including the defect is excluded by a first failure location discharging device 6 described later, and is not attached to the optical display unit W. That is, the present invention is characterized in that it includes a defect portion elimination step of cutting and eliminating a portion having a defect of the long roll when supplying the first long roll F1 and the second long roll F2.

  In addition, as shown in FIG.3 (b) and FIG. 4, the failure part discharge apparatus is a member (failure part) which can affix the part (failure part) which has the fault of a long roll instead of the optical display unit W. And a structure in which a part of the member is movable in accordance with the length of the failure part to be removed. That is, this makes it possible to cut and remove the faulty part found by the in-line inspection for the long sheet product. Moreover, when cut | disconnecting a long roll, it is preferable to match | combine height with a failure location bonding part and an optical display unit.

  4 and 5 show an outline of the failure location discharging apparatus. FIG. 4 illustrates an image in which the failure location bonding unit of the failure location discharge device moves the movement location according to the size of the failure location. The long roll is detected by the in-line inspection machine in the length direction of the failure part, and can be moved to the length corresponding to the moving part of the failure part bonding part. The moving part moves according to the failure information obtained by the above.

  FIG. 5 shows a schematic structure of the failure location discharging apparatus. The failure part bonding part is installed in the movable part and the end part of the actuator. The discharged polarizing plate needs to be peeled off quickly. Therefore, for the purpose of improving the releasability, for example, this failure location bonding portion is coated with a silicone resin, and so on. This is preferable because the bonded failure part can be peeled off at high speed. The actuator can be appropriately selected from a linear motor, a ball screw, and a chain. From the viewpoint of driving speed, accuracy, and ease of maintenance, it is preferable to use a single-axis linear servo type.

(7-1) Optical display unit cleaning process (FIG. 1, S7-1)
The surface of the optical display unit W is cleaned by, for example, a polishing cleaning device and a water cleaning device. The cleaned optical display unit W is transported to the inspection apparatus by the transport mechanism. The transport mechanism includes, for example, a transport roller, a transport direction switching mechanism, a rotation drive device, a sensor device, and a control device.

(7-2) Inspection process (FIG. 1, S7-2)
The surface of the cleaned optical display unit W is inspected by, for example, an inspection apparatus. The optical display unit W after inspection is conveyed to the 1st bonding apparatus 18 by the conveyance mechanism.

  The first polarizing plate long roll preparation process, the first inspection process, the first long roll bonding process, the cleaning process, the first cutting process, and the optical display unit inspection process are performed on a continuous production line. It is preferred that

  In the series of manufacturing steps described above, the first long roll F1 was bonded to one surface of the optical display unit W. Below, the manufacturing process which bonds the 2nd elongate roll F2 on another surface is demonstrated.

(8) Second polarizing plate long roll preparation step (FIG. 1, S11)
A long second sheet product F2 is prepared as a second polarizing plate long roll as described below.

(9) Second conveying step (FIG. 1, S12)
The second sheet product F2 is fed out from the prepared second polarizing plate long roll and conveyed downstream. The second conveying device 12 that conveys the second sheet product is composed of, for example, a nip roller pair, a tension roller, a rotation driving device, an accumulating device A, a sensor device, a control device, and the like. Therefore, it is preferable to use a roll that is processed with silicon, fluorine resin, or the like so that the adhesive layer does not come into contact with the roll. The first roll is not used to transfer the adhesive layer, but may be used as part of the leader.

(9) Second inspection process (FIG. 1, S13)
A defect of the second sheet product F2 is inspected using the second inline inspection device 13. The defect inspection method here is the same as the method using the first in-line inspection apparatus described above.

(10) 2nd long roll bonding process (FIG. 1, S14)
Next, after the second cutting step, the second long roll F2 is bonded to a surface different from the surface on which the first long roll F1 of the optical display unit W is bonded via the adhesive layer. At the time of bonding, the second long roll F2 and the optical display unit W are sandwiched between the rolls and are bonded by pressure.

  In the present invention, since the first long roll F2 is bonded to the optical display unit W before cutting, the problem of curling of the polarizing plate can be solved.

(11) Second cutting step (FIG. 1, S15)
Since the width of the second polarizing plate long roll corresponds to the long side of the optical display unit, the long roll is cut at a length corresponding to the short side.

  In addition, when the polarizing plate protective film which can peel is provided in the 1st elongate roll F11, the layer except the said polarizing plate protective film is cut | disconnected. Regarding the cutting length, since the width of the first polarizing plate long roll corresponds to the short side, the long roll is cut at a length corresponding to the long side.

  In the present embodiment, as shown in FIG. 2, an example in which the width of the second polarizing plate long roll (second sheet product F <b> 2) corresponds to the long side of the optical display unit W is shown.

  Examples of the cutting means include a laser device, a cutter, and other known cutting means.

(12) Failure location discharge process (FIG. 1, S16)
Based on the defect information obtained by the second in-line inspection apparatus 13, it is configured to cut away from the defect so that the defect is not included in the region bonded to the optical display unit W. Thereby, the yield of the second sheet product F2 is greatly improved. The second sheet product F2 including the defect is excluded by a second failure location discharge device 16 described later, and is not attached to the optical display unit W.

(13) Optical display device inspection process (FIG. 1, S18)
The inspection device inspects an optical display device having long rolls attached to both sides. Examples of the inspection method include a method of taking an image and processing an image using reflected light on both sides of the optical display device. As another method, a method of installing a polarizing film for inspection between the CCD camera and the inspection object is also exemplified. Note that a known method can be applied to the image processing algorithm, and for example, a defect can be detected by density determination by binarization processing.

(14) Determination of non-defective product of optical display device Based on information on defects obtained by the inspection device, non-defective product determination of the optical display device is performed. The optical display device determined to be non-defective is conveyed to the next mounting process. If a defective product is determined, a rework process is performed, a new long roll is applied, and then inspected. If a good product is determined, the process proceeds to the mounting process. If a defective product is determined, the rework process is performed again. Or it is disposed of.

  In the above series of manufacturing processes, the optical display device can be suitably manufactured by executing the bonding process of the first long roll F1 and the second long roll F2 bonding process on a continuous production line. it can. In particular, by performing the above steps inside an isolation structure isolated from the factory, a long roll can be bonded to the optical display unit in an environment in which cleanliness is ensured, and a high-quality optical display device is manufactured. be able to.

  As can be seen from the above-described embodiments, the means of the present invention can provide a manufacturing system and a manufacturing method capable of forming an optical display device with a high yield using a long polarizing plate roll. .

(Polarizing plate long roll material)
Hereinafter, the polarizing plate long roll constituting material according to the present invention will be described in detail.

(Resin film substrate)
Various resin film base materials can be used for the polarizing film protective film and the polarizing plate protective film according to the present invention.

  The resin film substrate according to the present invention is preferably a material soluble in a solvent, and is preferably a thermoplastic resin. Here, the “thermoplastic resin” refers to a resin that can be softened and heated to a desired shape by heating from near the glass transition temperature to the melting point.

  General thermoplastic resins include cellulose esters, polyethylene (PE), high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene. (PS), polyvinyl acetate (PVAc), Teflon (registered trademark) (polytetrafluoroethylene, PTFE), ABS resin (acrylonitrile butadiene styrene resin), AS resin, acrylic resin (PMMA), etc., soluble in solvents It is preferable to dissolve the material appropriately and treat it by the method according to the present invention.

  When strength and resistance to breakage are particularly required, polyamide (PA), nylon, polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO), polybutylene terephthalate (PBT) ), Polyethylene terephthalate (PET), glass fiber reinforced polyethylene terephthalate (GF-PET), cyclic polyolefin (COP), and the like.

  If higher heat distortion temperature and long-term use characteristics are required, polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone, polyethersulfone, amorphous polyarylate, liquid crystal polymer, polyetherether A ketone, thermoplastic polyimide (PI), polyamideimide (PAI), or the like can be used.

  In addition, it is possible to perform the kind of resin and the combination of molecular weight according to the use of this invention.

  The thickness of the support is preferably appropriately selected according to the application. The upper limit of the thickness is not particularly limited, but in the case of forming a film by a solution casting method, the upper limit is about 250 μm from the viewpoint of applicability, foaming, solvent drying, and the like.

  The resin substrate preferably has a total light transmittance of 90% or more, more preferably 93% or more. Moreover, as a realistic upper limit, it is about 99%. In order to achieve excellent transparency expressed by such total light transmittance, it is necessary not to introduce additives and copolymerization components that absorb visible light, or to remove foreign substances in the polymer by high-precision filtration. It is effective to reduce the diffusion and absorption of light inside the film.

  Hereinafter, a particularly preferred resin in the present invention will be described in detail.

<Cellulose ester resin>
The cellulose ester resin that can be used in the present invention is selected from cellulose (di, tri) acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, and cellulose phthalate. It is preferable that there is at least one.

  Among these, particularly preferable cellulose esters include cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.

  As a substitution degree of the mixed fatty acid ester, when having an acyl group having 2 to 4 carbon atoms as a substituent, when the substitution degree of the acetyl group is X and the substitution degree of the propionyl group or butyryl group is Y, A cellulose resin containing a cellulose ester that simultaneously satisfies the following formulas (I) and (II) is preferable.

Formula (I) 2.0 ≦ X + Y ≦ 3.0
Formula (II) 0 ≦ X ≦ 2.5
Furthermore, the cellulose ester used in the present invention preferably has a weight average molecular weight Mw / number average molecular weight Mn ratio of 1.5 to 5.5, particularly preferably 2.0 to 5.0, Preferably it is 2.5-5.0, More preferably, the cellulose ester of 3.0-5.0 is used preferably.

  The cellulose ester raw material cellulose used in the present invention may be wood pulp or cotton linter, and the wood pulp may be softwood or hardwood, but softwood is more preferred. A cotton linter is preferably used from the viewpoint of peelability during film formation. The cellulose ester made from these can be mixed suitably or can be used independently.

  For example, the ratio of cellulose ester derived from cellulose linter: cellulose ester derived from wood pulp (coniferous): cellulose ester derived from wood pulp (hardwood) is 100: 0: 0, 90: 10: 0, 85: 15: 0, 50:50: 0, 20: 80: 0, 10: 90: 0, 0: 100: 0, 0: 0: 100, 80:10:10, 85: 0: 15, 40:30:30.

  In the present invention, 1 g of cellulose ester resin is added to 20 ml of pure water (electric conductivity 0.1 μS / cm or less, pH 6.8), and the pH is 6 when stirred in a nitrogen atmosphere at 25 ° C. for 1 hr. It is preferable that the electric conductivity is 1 to 100 μS / cm.

<acrylic resin>
The acrylic resin that can be used in the present invention includes a methacrylic resin. Although it does not restrict | limit especially as resin, What consists of 50-99 mass% of methyl methacrylate units and 1-50 mass% of other monomer units copolymerizable with this is preferable.

  Other monomers that can be copolymerized include alkyl methacrylates having 2 to 18 carbon atoms, alkyl acrylates having 1 to 18 carbon atoms, acrylic acid, methacrylic acid, and the like. Saturated acids, maleic acids, fumaric acids, unsaturated divalent carboxylic acids such as itaconic acid, aromatic vinyl compounds such as styrene, α-methylstyrene, and nucleus-substituted styrene, α, β- such as acrylonitrile, methacrylonitrile, etc. Examples thereof include unsaturated nitrile, maleic anhydride, maleimide, N-substituted maleimide, glutaric anhydride, and the like. These may be used alone or in combination of two or more.

  Among these, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like are preferable, and methyl acrylate and n-butyl acrylate are particularly preferably used.

  A commercially available thing can also be used as an acrylic resin. For example, Delpet 60N, 80N (Asahi Kasei Chemicals Co., Ltd.), Dianal BR52, BR80, BR83, BR85, BR88 (Mitsubishi Rayon Co., Ltd.), KT75 (Electrochemical Industry Co., Ltd.) and the like can be mentioned. .

<Cyclic olefin resin>
In the present invention, it is also preferable to use a cyclic olefin resin. Examples of the cyclic olefin resin include norbornene resins, monocyclic olefin resins, cyclic conjugated diene resins, vinyl alicyclic hydrocarbon resins, and hydrides thereof. Among these, norbornene-based resins can be suitably used because of their good transparency and moldability.

  Examples of the norbornene-based resin include a ring-opening polymer of a monomer having a norbornene structure, a ring-opening copolymer of a monomer having a norbornene structure and another monomer, a hydride thereof, and a norbornene structure. An addition polymer of a monomer having a monomer, an addition copolymer of a monomer having a norbornene structure and another monomer, or a hydride thereof.

  Among these, a ring-opening (co) polymer hydride of a monomer having a norbornene structure is particularly suitable from the viewpoints of transparency, moldability, heat resistance, low hygroscopicity, dimensional stability, lightness, and the like. Can be used.

Examples of the monomer having a norbornene structure include bicyclo [2.2.1] hept-2-ene (common name: norbornene) and tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene. (Common name: dicyclopentadiene), 7,8-benzotricyclo [4.3.0.1 ^2,5 ] dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo [4.4.0. 1 ^2,5 . 1 ^7,10 ] dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds (for example, those having a substituent in the ring). Here, examples of the substituent include an alkyl group, an alkylene group, and a polar group. In addition, these substituents may be the same or different and a plurality may be bonded to the ring. Monomers having a norbornene structure can be used singly or in combination of two or more.

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

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

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

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

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

  A hydrogenated product of a ring-opening polymer of a monomer having a norbornene structure, a hydrogenated product of a ring-opening copolymer of a monomer having a norbornene structure and another monomer capable of ring-opening copolymerization thereof, Hydrogenated products of addition polymers of monomers having a norbornene structure, and hydrogenated products of addition copolymers of monomers having a norbornene structure and other monomers capable of addition copolymerization with these A known hydrogenation catalyst containing a transition metal such as nickel or palladium is added to the polymer solution, and the carbon-carbon unsaturated bond is preferably hydrogenated by 90% or more.

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

  The molecular weight of the cyclic olefin resin used in the present invention is appropriately selected according to the purpose of use. Polyisoprene or polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography using cyclohexane (toluene if the polymer resin does not dissolve) as a solvent, usually 20,000 to 150,000. . Preferably it is 25,000-100,000, More preferably, it is 30,000-80,000. When the weight average molecular weight is in such a range, the mechanical strength and molding processability of the film are highly balanced and suitable.

  The glass transition temperature of the cyclic olefin resin may be appropriately selected according to the purpose of use. From the viewpoint of durability and stretchability, it is preferably in the range of 130 to 160 ° C, more preferably 135 to 150 ° C.

  The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the cyclic olefin resin is 1.2 to 3.5, preferably 1.5 to 3.0, from the viewpoint of relaxation time, productivity, and the like. More preferably, it is 1.8 to 2.7.

The cyclic olefin resin used in the present invention preferably has an absolute value of photoelastic coefficient of 10 × 10 ⁻¹² Pa ⁻¹ or less, more preferably 7 × 10 ⁻¹² Pa ⁻¹ or less, and more preferably 4 × 10. It is particularly preferably ⁻¹² Pa ⁻¹ or less. The photoelastic coefficient C is a value represented by C = Δn / σ where birefringence is Δn and stress is σ.

  In the present invention, it is preferable that the cyclic olefin resin does not substantially contain particles. Here, “substantially free of particles” means that even if particles are added to a film made of a cyclic olefin resin, the amount of increase in haze from the non-added state is allowed to be in the range of 0.05% or less. Means you can. In particular, the alicyclic polyolefin resin lacks affinity with many organic particles and inorganic particles. Therefore, when a cyclic olefin resin film to which particles exceeding the above range are added is stretched, voids are easily generated, and as a result, There is a risk that a significant decrease in haze occurs.

<Polycarbonate resin>
In the present invention, various known polycarbonate resins can also be used. In the present invention, it is particularly preferable to use an aromatic polycarbonate. There is no restriction | limiting in particular about the said aromatic polycarbonate, and there will be no restriction | limiting in particular if it is an aromatic polycarbonate from which the various characteristics of a desired film are acquired.

  In general, a polymer material collectively referred to as polycarbonate is a generic term for a polymer material in which a polycondensation reaction is used in its synthesis method and the main chain is linked by a carbonic acid bond. , Phosgene, diphenyl carbonate and the like obtained by polycondensation. Usually, an aromatic polycarbonate represented by a repeating unit having 2,2-bis (4-hydroxyphenyl) propane called bisphenol-A as a bisphenol component is preferably selected, and various bisphenol derivatives should be appropriately selected. Thus, an aromatic polycarbonate copolymer can be constituted.

  In addition to this bisphenol-A, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 1,1 -Bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) -2-phenyl Ethane, 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) sulfide, bis ( 4-hydroxyphenyl) sulfone, 1,1-bis (4-hydroxyphenyl) -3,3,5-tri Mention may be made of a chill cyclohexane, and the like.

  It is also possible to use an aromatic polyester carbonate partially containing terephthalic acid and / or isophthalic acid components. By using such a structural unit as a part of the structural component of the aromatic polycarbonate composed of bisphenol-A, the properties of the aromatic polycarbonate, such as heat resistance and solubility, can be improved. The present invention is also effective for coalescence.

  If the aromatic polycarbonate used here has a viscosity average molecular weight of 10,000 or more and 200,000 or less, it is suitably used. A viscosity average molecular weight of 20,000 to 120,000 is particularly preferred. If a resin having a viscosity average molecular weight lower than 10,000 is used, the mechanical strength of the resulting film may be insufficient, and if it has a high molecular weight of 400000 or more, the viscosity of the dope becomes too large, causing problems in handling. The viscosity average molecular weight can be measured by commercially available high performance liquid chromatography.

  The glass transition temperature of the aromatic polycarbonate according to the present invention is preferably 200 ° C. or higher in order to obtain a highly heat-resistant film, and more preferably 230 ° C. or higher. These can be obtained by appropriately selecting the copolymerization component. The glass transition temperature can be measured with a DSC apparatus (differential scanning calorimetry apparatus). For example, the Seiko Instruments Inc. product: RDC220 calculates the temperature at 10 ° C./min. It is the temperature that begins to do.

  In the present invention, the solvent used for the dope composition containing the aromatic polycarbonate is a mixed solvent containing 4 to 14 parts by mass of methylene chloride and a linear or branched aliphatic alcohol having 1 to 6 carbon atoms. It is preferable.

  The mixing amount of the linear or branched aliphatic alcohol having 1 to 6 carbon atoms is preferably 4 to 12 parts by mass. By using such a mixed solvent, the web is peeled off at a higher residual solvent concentration than before, thereby suppressing the generation of strong static electricity when the web is peeled off, thereby causing damage to the belt, film streaks, unevenness, and minuteness. Scratches can be prevented from occurring.

  The type of alcohol added is limited by the solvent used. It is a necessary condition that the alcohol and the solvent are compatible. These may be added alone or in combination of two or more. The alcohol in the present invention is preferably a linear or branched aliphatic alcohol having 1 to 6, preferably 1 to 4, more preferably 2 to 4 carbon atoms. Specific examples include methanol, ethanol, isopropanol, and tertiary butanol. Of these, ethanol, isopropanol, and tertiary butanol can achieve almost the same effect, but methanol has a slightly lower effect. Although the reason is not clear, it is presumed that the boiling point of the solvent, that is, the ease of flying during drying is related. Higher alcohols higher than that are not preferred because they have a high boiling point and are likely to remain after film formation.

  The amount of alcohol added must be carefully selected. These alcohols are completely poor in solubility in aromatic polycarbonate and are completely poor solvents. Therefore, it cannot be added too much, and should be the minimum amount that provides satisfactory peelability. As mentioned above, it is 4-14 mass parts with respect to a methylene chloride, Preferably it is 4-12 mass parts. When the addition amount is in the range of 4 to 14 parts by mass with respect to the amount of methylene chloride, the solubility of the solvent in the polymer and the dope stability are improved, and the effect of improving the peelability is increased.

  The present invention comprises the above methylene chloride and aliphatic alcohol in the dope composition, but other solvents can also be used. The remaining solvent is not particularly limited as long as it dissolves the aromatic polycarbonate at a high concentration and is compatible with alcohol, and is a low-boiling solvent. For example, as a solvent having a solubility in an aromatic polycarbonate, in addition to methylene chloride, halogen solvents such as chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, 1,3-dioxolane, 1, Examples include cyclic ether solvents such as 4-dioxane and tetrahydrofuran, and ketone solvents such as cyclohexanone.

  When using other solvent, there is no limitation in particular and it may use it in consideration of an effect. The effects here include mixing the solvent without sacrificing solubility and stability, for example, improving the surface properties of the film formed by the solution casting method (leveling effect), evaporation rate and system These include viscosity adjustment and crystallization suppression effects. What is necessary is just to determine the kind and addition amount of the solvent to mix by the degree of these effects, and you may use 1 type, or 2 or more types as a solvent to mix.

  Other solvents preferably used include halogen solvents such as chloroform and 1,2-dichloroethane, hydrocarbon solvents such as toluene and xylene, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, and ethyl acetate and butyl acetate. Examples include ester solvents, ether solvents such as ethylene glycol dimethyl ether and methoxyethyl acetate.

  The dope composition according to the present invention may be prepared by any method as long as a transparent solution having a low haze is obtained as a result. A predetermined amount of alcohol may be added to the aromatic polycarbonate solution dissolved in a certain solvent in advance, or the aromatic polycarbonate may be dissolved in a mixed solvent containing alcohol. However, as described above, since alcohol is a poor solvent, the method of adding the latter after the former may cause clouding of the dope due to the precipitation of the polymer. Therefore, the method of dissolving in the latter mixed solvent is preferable.

<Polyester resin>
The polyester resin that can be used in the present invention is obtained by polymerizing a dicarboxylic acid and a diol, and 70% or more of dicarboxylic acid structural units (constituent units derived from dicarboxylic acid) are derived from aromatic dicarboxylic acid, and 70% or more of the diol constituent units (constituent units derived from the diol) are derived from the aliphatic diol.

  The proportion of the structural unit derived from the aromatic dicarboxylic acid is 70% or more, preferably 80% or more, more preferably 90% or more.

  The proportion of the structural unit derived from the aliphatic diol is 70% or more, preferably 80% or more, and more preferably 90% or more. Two or more polyester resins may be used in combination.

  Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, naphthalenedicarboxylic acid such as 2,7-naphthalenedicarboxylic acid, and 4,4′-biphenyldicarboxylic acid. 3,4'-biphenyldicarboxylic acid and the like and ester-forming derivatives thereof.

  As the polyester resin, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, and sebacic acid, and monocarboxylic acids such as benzoic acid, propionic acid, and butyric acid can be used without departing from the object of the present invention.

  Examples of the aliphatic diol include ethylene glycol, 1,3-propylene diol, 1,4-butanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol, and the like, and ester-forming derivatives thereof.

  As the polyester resin, monoalcohols such as butyl alcohol, hexyl alcohol, and octyl alcohol, and polyhydric alcohols such as trimethylolpropane, glycerin, and pentaerythritol can be used as long as the object of the present invention is not impaired.

  A known esterification method or transesterification method can be applied to the production of the polyester resin. Examples of the polycondensation catalyst used in the production of the polyester resin include known antimony compounds such as antimony trioxide and antimony pentoxide, germanium compounds such as germanium oxide, titanium compounds such as titanium acetate, and aluminum compounds such as aluminum chloride. Although it can, it is not limited to these.

  Preferred polyester resins include polyethylene terephthalate resin, polyethylene terephthalate-isophthalate copolymer resin, polyethylene-1,4-cyclohexanedimethylene-terephthalate copolymer resin, polyethylene-2,6-naphthalene dicarboxylate resin, polyethylene-2, 6-naphthalene dicarboxylate-terephthalate copolymer resin, polyethylene-terephthalate-4,4'-biphenyldicarboxylate resin, poly-1,3-propylene-terephthalate resin, polybutylene terephthalate resin, polybutylene-2,6-naphthalene There are dicarboxylate resins and the like.

  More preferable polyester resins include polyethylene terephthalate resin, polyethylene terephthalate-isophthalate copolymer resin, polyethylene-1,4-cyclohexanedimethylene-terephthalate copolymer resin, polybutylene terephthalate resin, and polyethylene-2,6-naphthalene dicarboxylate. Resin.

  The intrinsic viscosity of the polyester resin (phenol / 1,1,2,2-tetrachloroethane = value measured at 25 ° C. in a 60/40 mass ratio mixed solvent) is preferably 0.7 to 2.0 dl / g, more Preferably it is 0.8-1.5 dl / g. Since the molecular weight of the polyester resin is sufficiently high when the intrinsic viscosity is 0.7 or more, the molded product comprising the polyester resin composition obtained by using the polyester resin has mechanical properties necessary for the molded product and is transparent. Property is improved. When the intrinsic viscosity is 2.0 or less, the moldability is good.

(Other additives)
The thermoplastic resin substrate according to the present invention can contain various compounds as additives depending on the purpose. For example, a plasticizer, an antioxidant, an acid scavenger, a light stabilizer, an ultraviolet absorber, an optical anisotropy control agent, a matting agent, an antistatic agent, a release agent, and the like can be contained.

  Among the additives, it is an optical anisotropy control agent that effectively contributes to the present invention, and in particular, the retardation increasing agent makes it easy to develop birefringence optically in an oblique direction from the intended plane. Therefore, it is preferable. The retardation increasing agent is preferably an aromatic compound having at least two aromatic rings. The aromatic compound is preferably used in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of the resin. And it is preferable to use in 0.05-15 mass parts, and it is still more preferable to use in 0.1-10 mass parts. Two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound includes an aromatic hetero ring in addition to the aromatic hydrocarbon ring. The aromatic hydrocarbon ring is particularly preferably a 6-membered ring (that is, a benzene ring). The aromatic heterocycle is generally an unsaturated heterocycle. The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring. Aromatic heterocycles generally have the most double bonds. As the hetero atom, a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable. Examples of aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, triazole ring, pyran ring, pyridine ring , Pyridazine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring. Details of these are described in JP-A No. 2004-109410, JP-A No. 2003-344655, JP-A No. 2000-275434, JP-A No. 2000-1111914, JP-A No. 12-275434, and the like.

(Matting agent)
The thermoplastic resin substrate according to the present invention may be added with fine particles as a matting agent in order to prevent scratching or deterioration of transportability when the produced film is handled. preferable.

  As fine particles, examples of inorganic compounds include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, Examples thereof include magnesium silicate and calcium phosphate. Fine particles containing silicon are preferable in terms of low turbidity, and silicon dioxide is particularly preferable.

  The average primary particle diameter of the fine particles is preferably 5 to 400 nm, and more preferably 10 to 300 nm. These may be mainly contained as secondary aggregates having a particle size of 0.05 to 0.3 μm, and may be contained as primary particles without being aggregated if the particles have an average particle size of 100 to 400 nm. preferable. The content of these fine particles in the film is preferably 0.01 to 1% by mass, particularly preferably 0.05 to 0.5% by mass. In the case of an optical film having a multilayer structure by the co-casting method, it is preferable to contain fine particles of this addition amount on the surface.

  Silicon dioxide fine particles are commercially available, for example, under the trade names Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (above Nippon Aerosil Co., Ltd.). it can.

  Zirconium oxide fine particles are commercially available, for example, under the trade names Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used.

  Examples of the resin include a silicone resin, a fluororesin, and an acrylic resin. Silicone resins are preferable, and those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120, and 240 (manufactured by Toshiba Silicone Co., Ltd.) It is marketed by name and can be used.

  Among these, Aerosil 200V and Aerosil R972V are particularly preferably used because they have a large effect of reducing the friction coefficient while keeping the haze of the optical film low. In the optical film according to the present invention, the dynamic friction coefficient of at least one surface is preferably 0.2 to 1.0.

(Manufacturing method of base film)
Examples of the method for producing the polarizing film protective film and the base film of the polarizing plate protective film according to the present invention include a normal inflation method, a T-die method, a calendar method, a cutting method, a casting method, an emulsion method, a hot press method, and the like. However, the solution casting method and the melt casting method by the casting method are preferable from the viewpoints of suppressing coloring, suppressing defects of foreign matters, and suppressing optical defects such as die lines. Below, manufacture of the cellulose-ester film used for a polarizing film protective film is demonstrated as an example.

<Production example of cellulose ester film>
The cellulose ester film according to the present invention is produced by a solution casting method in which a cellulose ester and an additive are dissolved in a solvent to prepare a dope, and a dope is cast on a metal support such as a belt or a drum. It is performed by a step of drying the cast dope as a web, a step of peeling from the metal support, a step of stretching or maintaining the width, a step of further drying, and a step of winding up the finished film.

<< About the process of preparing dope >>
The concentration of cellulose ester in the dope is preferably higher because the drying load after casting on the metal support can be reduced. However, if the concentration of cellulose ester is too high, the load during filtration increases and the filtration accuracy is poor. Become. As a density | concentration which makes these compatible, 10-35 mass% is preferable, More preferably, it is 15-25 mass%.

  The organic solvent is a solvent selected from ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, esters having 3 to 12 carbon atoms, and halogenated hydrocarbons having 1 to 6 carbon atoms. It is preferable to contain. The ether, ketone and ester may have a cyclic structure. A compound having two or more functional groups of ether, ketone, and ester (that is, —O—, —CO—, and COO—) can also be used as the organic solvent. The organic solvent may have another functional group such as an alcoholic hydroxy group (hydroxyl group).

  In the case of an organic solvent having two or more types of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group.

  Examples of the ether having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.

  Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone.

  Examples of the esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.

  Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.

  The number of carbon atoms of the halogenated hydrocarbon is preferably 1 or 2, and most preferably 1. The halogen of the halogenated hydrocarbon is preferably chlorine. The proportion of halogen atoms substituted by halogen in the halogenated hydrocarbon is preferably 25 to 75 mol%, more preferably 30 to 70 mol%, and more preferably 35 to 65 mol%. More preferably, it is most preferable that it is 40-60 mol%. Methylene chloride is a representative halogenated hydrocarbon. These are called good solvents.

  The dope preferably contains 1 to 40% by mass of an alcohol having 1 to 4 carbon atoms in addition to the organic solvent. After casting the dope on the metal support, the solvent starts to evaporate and the alcohol ratio increases, so that the web (referred to as the dope film after casting the cellulose derivative dope on the support is called web As a gelling solvent that makes it easy to peel off from the metal support, and when these ratios are small, it promotes the dissolution of cellulose derivatives of non-chlorine organic solvents There is also a role to suppress gelation, precipitation, and viscosity increase of the reactive metal compound.

  Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol, and propylene glycol monomethyl ether. Of these, ethanol is preferred because of its excellent dope stability, relatively low boiling point, and good drying properties. These are called poor solvents.

  Moreover, the solvent used for melt | dissolution of a cellulose ester collect | recovers the solvent removed from the film by drying at the film-forming process, and uses this again.

  There may be a trace amount of additives added to the cellulose ester in the recovered solvent, but even if they are contained, they can be reused preferably, and if necessary, purified and reused. You can also

  As a method for dissolving the cellulose ester when preparing the dope, a general method can be used. When heating and pressurization are combined, it is possible to heat above the boiling point at normal pressure.

  It is preferable to stir and dissolve while heating at a temperature that is equal to or higher than the boiling point of the solvent at normal pressure and that the solvent does not boil under pressure, in order to prevent the generation of massive undissolved materials called gels and mamacos.

  A method in which a cellulose ester is mixed with a poor solvent and wetted or swollen, and then a good solvent is added and dissolved is also preferably used.

  The pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or a method of increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside. For example, a jacket type is preferable because temperature control is easy.

  The heating temperature with the addition of a solvent is preferably higher from the viewpoint of the solubility of the cellulose ester, but if the heating temperature is too high, the required pressure increases and the productivity deteriorates.

  A preferable heating temperature is 45 to 120 ° C, more preferably 60 to 110 ° C, and still more preferably 70 ° C to 105 ° C. The pressure is adjusted so that the solvent does not boil at the set temperature.

  In the present invention, a cooling dissolution method is also preferably used, whereby the cellulose ester can be dissolved in a solvent such as methyl acetate.

  Next, this cellulose ester solution is filtered using a suitable filter medium such as filter paper. As the filter medium, it is preferable that the absolute filtration accuracy is small in order to remove insoluble matters and the like, but there is a problem that the filter medium is likely to be clogged if the absolute filtration accuracy is too small.

  For this reason, a filter medium with an absolute filtration accuracy of 0.008 mm or less is preferable, a filter medium with 0.001 to 0.008 mm is more preferable, and a filter medium with 0.003 to 0.006 mm is still more preferable.

  There are no particular restrictions on the material of the filter medium, and ordinary filter media can be used. However, plastic filter media such as polypropylene and Teflon (registered trademark), and metal filter media such as stainless steel do not drop off fibers. preferable.

  It is preferable to remove and reduce impurities, particularly bright spot foreign matter, contained in the raw material cellulose ester by filtration.

Bright spot foreign matter is when two polarizing plates are placed in a crossed Nicol state, an optical film or the like is placed between them, light is applied from one polarizing plate side, and observation is performed from the other polarizing plate side. It is a point (foreign matter) where light from the opposite side appears to leak, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 / cm ² or less.

More preferably, it is 100 pieces / cm < ² > or less, More preferably, it is 50 pieces / m < ² > or less, More preferably, it is 0-10 pieces / cm < ² > or less. Further, it is preferable that the number of bright spots of 0.01 mm or less is small.

  The dope can be filtered by a normal method, but the method of filtering while heating at a temperature not lower than the boiling point of the solvent at normal pressure and in a range where the solvent does not boil under pressure is the filtration pressure before and after filtration. The increase in the difference (referred to as differential pressure) is small and preferable.

  A preferred temperature is 45 to 120 ° C, more preferably 45 to 70 ° C, and still more preferably 45 to 55 ° C.

  A smaller filtration pressure is preferred. The filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and further preferably 1.0 MPa or less.

《Dope casting process》
The metal support in the casting (casting) step preferably has a mirror-finished surface. As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used.

  The cast width can be 1 to 4 m. The surface temperature of the metal support in the casting step is −50 ° C. to a temperature lower than the boiling point of the solvent, and a higher temperature is preferable because the web can be dried faster. May deteriorate.

  A preferable support temperature is 0 to 55 ° C, and more preferably 25 to 50 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and peeled from the drum in a state containing a large amount of residual solvent.

  The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing warm air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use warm water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short. When warm air is used, wind at a temperature higher than the target temperature may be used.

  In order for the cellulose ester film to exhibit good flatness, the residual solvent amount when peeling the web from the metal support is preferably 10 to 150% by mass, more preferably 20 to 40% by mass or 60 to 130% by mass. Especially preferably, it is 20-30 mass% or 70-120 mass%.

  In the present invention, the amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Note that M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

<< About the drying process >>
In the drying step of the cellulose ester film, the web is peeled off from the metal support and further dried, and the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less, and particularly preferably. Is 0 to 0.01% by mass or less.

  In the film drying step, generally, a roll drying method (a method in which webs are alternately passed through a plurality of rolls arranged above and below) and a method in which the web is dried while being conveyed by a tenter method are employed.

  In order to produce the cellulose ester film according to the present invention, it is particularly preferable to perform stretching in the width direction (lateral direction) by a tenter method in which both ends of the web are held with clips or the like. Peeling is preferably performed at a peeling tension of 300 N / m or less.

  The means for drying the web is not particularly limited, and can be generally performed with hot air, infrared rays, a heating roll, microwave, or the like, but it is preferably performed with hot air in terms of simplicity.

  The drying temperature in the web drying step is preferably increased stepwise from 40 to 200 ° C.

  The thickness (film thickness) of the cellulose ester film is preferably 20 to 50 μm.

  The cellulose ester film according to the present invention has a width of 1 to 4 m. In particular, those having a width of 1.4 to 4 m are preferably used, and particularly preferably 1.9 to 2.5 m. By making it in this range, it is possible to achieve both efficient polarizing plate cutting and handling suitability.

  In addition, the cellulose ester film according to the present invention preferably has a length of 100 m to 10000 m, more preferably 1000 m to 10000 m, and particularly preferably 5000 m to 10000 m per roll. By setting it as this range, it is easy to handle in a roll form, and further, it has an effect of being adapted to a continuous process of polarizing plates and improving the yield.

  In order to impart the following desired retardation values (Ro, Rt) to the cellulose ester film, the cellulose ester film may have the configuration of the present invention, and the refractive index may be controlled by controlling the transport tension and stretching operation. preferable.

  For example, the retardation value can be changed by lowering or increasing the tension in the longitudinal direction.

  Moreover, it is preferable to carry out biaxial stretching or uniaxial stretching sequentially or simultaneously with respect to the longitudinal direction (film forming direction) of the film and the direction orthogonal to the longitudinal direction of the film, that is, the width direction.

  It is preferable that the draw ratios in the biaxial directions perpendicular to each other are finally in the range of 0.8 to 1.5 times in the casting direction and 1.1 to 2.5 times in the width direction. It is preferable to carry out in the range of 0.8 to 1.0 times in the direction and 1.2 to 2.0 times in the width direction.

  The stretching temperature is preferably 120 ° C to 200 ° C, more preferably 120 ° C to 180 ° C, and further preferably 120 ° C to 160 ° C.

  The residual solvent in the film at the time of stretching is preferably 20 to 0%, more preferably 15 to 0%.

  There is no particular limitation on the method of stretching the web. For example, a method in which a difference in peripheral speed is applied to a plurality of rolls, and the roll peripheral speed difference is used to stretch in the longitudinal direction, the both ends of the web are fixed with clips and pins, and the interval between the clips and pins is increased in the traveling direction. And a method of stretching in the vertical direction, a method of stretching in the horizontal direction and stretching in the horizontal direction, a method of stretching in the vertical and horizontal directions and stretching in both the vertical and horizontal directions, and the like. Of course, these methods may be used in combination.

  In the case of the so-called tenter method, driving the clip portion by the linear drive method is preferable because smooth stretching can be performed and the risk of breakage and the like can be reduced.

  These width maintenance or lateral stretching in the film forming step is preferably performed by a tenter, and may be a pin tenter or a clip tenter.

  The slow axis or the fast axis of the cellulose ester film according to the present invention is present in the film plane, and θ1 is preferably −1 ° or more and + 1 ° or less when the angle formed with the film forming direction is θ1. It is more preferably 0.5 ° or more and + 0.5 ° or less, and further preferably −0.1 ° or more and + 0.1 ° or less.

  This θ1 can be defined as an orientation angle, and θ1 can be measured using an automatic birefringence meter KOBRA-21ADH (Oji Scientific Instruments). Each of θ1 satisfying the above relationship can contribute to obtaining high luminance in a display image, suppressing or preventing light leakage, and contributing to obtaining faithful color reproduction in a color liquid crystal display device.

(Conclusion)
By the means of the present invention described in detail above, in the production of an optical display device using a polarizing plate long roll, the production system capable of preventing the curling of the polarizing plate and forming the optical display device with a high yield. And a manufacturing method can be provided.

F1 1st elongate sheet product F2 2nd elongate sheet product R1 1st elongate roll R2 2nd elongate roll M1 1st bonding cutting apparatus M2 2nd bonding cutting apparatus W Optical display unit 1 Optical display unit Transport and supply device 2, 12 long roll transport and supply device 3, 13 in-line inspection device 4, 14 bonding device 5, 15 cutting device 6, 16 failure location discharging device 7 optical display unit W after bonding and cutting Conveying and supplying device 17 Conveying device of optical display device WA formed after pasting and cutting 18 Failure location laminating section 19 Failure location 20 Separator film winding device 21 Actuator F Long sheet product L Length of film including failure location (The moving part changes according to this length.)

Claims (3)

A manufacturing system of an optical display device formed by laminating and cutting a polarizing plate included in a polarizing plate long roll on an optical display unit, wherein the polarizing plate long roll is a short side of the optical display unit or It consists of an optical film provided with at least a polarizing plate and an adhesive layer, wound up into a long sheet having a width corresponding to the long side, and at least the following first bonding cutting device, second bonding cutting device, and An optical display device manufacturing system comprising a failure location discharging device.
(1) First bonding / cutting device: a long polarizing plate roll (referred to as a “first long roll”) wound into a long sheet having a width corresponding to the short side of the optical display unit. An apparatus that pulls out a sheet-like product, performs in-line inspection, and bonds it to one surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(2) Second bonding / cutting device: long from a polarizing plate long roll (referred to as “second long roll”) wound into a long sheet having a width corresponding to the long side of the optical display unit. A device that pulls out a sheet-like product, performs in-line inspection, and bonds it to the other surface of the optical display unit, and then cuts the optical film on the roll side of the optical display unit.
(3) Failure location discharge device: A device that cuts and removes the failure location found by in-line inspection of the long sheet product.   2. The optical display according to claim 1, wherein the failure location discharging device has a function of cutting and removing by changing the length of the long side or the length of the short side according to the width of the failure location. Equipment manufacturing system. A method of manufacturing an optical display device formed by laminating and cutting a polarizing plate contained in a polarizing plate long roll on an optical display unit, wherein the polarizing plate long roll is a short side of the optical display unit or It consists of an optical film provided with at least a polarizing plate and an adhesive layer, wound into a long sheet having a width corresponding to the long side, and at least the following first bonding cutting step, second bonding cutting step, and A method of manufacturing an optical display device comprising a failure location discharging step.
(1) 1st bonding cutting process: It is long from the polarizing plate long roll (it is called "1st long roll") wound up by the long sheet form of the width | variety corresponding to the short side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the sheet-like product to one surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(2) 2nd bonding cutting process: It is long from the polarizing plate elongate roll (it is called "2nd elongate roll") wound up by the elongate sheet form of the width | variety corresponding to the long side of the said optical display unit. A step of drawing the sheet-like product, performing an in-line inspection, bonding the other product to the other surface of the optical display unit, and then cutting the optical film on the roll side of the optical display unit.
(3) Failure location discharging step: A step of cutting and removing the failure location found by in-line inspection of the long sheet product.