WO2017122470A1 - Procédé de fabrication de film optique - Google Patents

Procédé de fabrication de film optique Download PDF

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Publication number
WO2017122470A1
WO2017122470A1 PCT/JP2016/086561 JP2016086561W WO2017122470A1 WO 2017122470 A1 WO2017122470 A1 WO 2017122470A1 JP 2016086561 W JP2016086561 W JP 2016086561W WO 2017122470 A1 WO2017122470 A1 WO 2017122470A1
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WO
WIPO (PCT)
Prior art keywords
film
adhesive composition
optical film
polarizer
producing
Prior art date
Application number
PCT/JP2016/086561
Other languages
English (en)
Japanese (ja)
Inventor
雅 品川
真 宮崎
Original Assignee
日東電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日東電工株式会社 filed Critical 日東電工株式会社
Priority to CN201680074426.9A priority Critical patent/CN108431650B/zh
Priority to KR1020187018163A priority patent/KR102574007B1/ko
Publication of WO2017122470A1 publication Critical patent/WO2017122470A1/fr

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/12Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by using adhesives
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D1/00Processes for applying liquids or other fluent materials
    • B05D1/28Processes for applying liquids or other fluent materials performed by transfer from the surfaces of elements carrying the liquid or other fluent material, e.g. brushes, pads, rollers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/02Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to macromolecular substances, e.g. rubber
    • B05D7/04Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to macromolecular substances, e.g. rubber to surfaces of films or sheets
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29DPRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D11/00Producing optical elements, e.g. lenses or prisms
    • B29D11/00634Production of filters
    • B29D11/00644Production of filters polarizing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29DPRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D11/00Producing optical elements, e.g. lenses or prisms
    • B29D11/0073Optical laminates
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29DPRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D11/00Producing optical elements, e.g. lenses or prisms
    • B29D11/00865Applying coatings; tinting; colouring
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00Layered products comprising a layer of synthetic resin
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00Layered products comprising a layer of synthetic resin
    • B32B27/06Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B27/08Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B32B37/0007Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding involving treatment or provisions in order to avoid deformation or air inclusion, e.g. to improve surface quality
    • B32B37/003Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding involving treatment or provisions in order to avoid deformation or air inclusion, e.g. to improve surface quality to avoid air inclusion
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B32LAYERED PRODUCTS
    • B32BLAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04Interconnection of layers
    • B32B7/12Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J201/00Adhesives based on unspecified macromolecular compounds
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J5/00Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J5/00Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers
    • C09J5/02Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers involving pretreatment of the surfaces to be joined
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00Optical elements other than lenses
    • G02B5/30Polarising elements

Definitions

  • the present invention relates to an optical film including a laminated structure in which at least a first film and a second film are bonded via an adhesive layer or an adhesive layer composed of a cured product layer of an adhesive composition or an adhesive composition. It relates to a manufacturing method.
  • Liquid crystal display devices are rapidly expanding in the market for watches, mobile phones, PDAs, notebook computers, personal computer monitors, DVD players, TVs, etc.
  • the liquid crystal display device visualizes the polarization state by switching of the liquid crystal, and a polarizer is used from the display principle.
  • polarizing films are also required to have higher transmittance, higher degree of polarization, and higher color reproducibility.
  • an iodine-based polarizer having a stretched structure by adsorbing iodine to polyvinyl alcohol (hereinafter also simply referred to as “PVA”) is most widely used. in use.
  • PVA polyvinyl alcohol
  • a polarizing film in which a transparent protective film is bonded to both surfaces of a polarizer by a so-called aqueous adhesive in which a polyvinyl alcohol-based material is dissolved in water has been used.
  • an active energy ray-curable resin composition that does not contain water or an organic solvent is becoming mainstream because it has advantages such that the drying step can be omitted and the dimensional change is small. is there.
  • the adhesive composition is applied only to the laminating surface of the transparent protective film, and the laminating surface.
  • an optical film including a laminated structure is manufactured by laminating a polarizer or the like from the side.
  • foreign matter such as dust or dust adheres to the surface of the polarizer / transparent protective film before application of the adhesive composition or the like, or the adhesive composition contains minute foreign matter. In this case, foreign matters remain in the adhesive layer, and as a result, appearance defects may occur.
  • an optical film including a step of thinly coating an optical functional layer having a wet coating amount of 10 mL / m 2 or less on a transparent support or an undercoat layer formed on the transparent support.
  • an optical film manufacturing method including a step of removing foreign matters having a height of 10 ⁇ m or more from the transparent support or the undercoat layer before applying the optical functional layer is described.
  • Patent Document 2 a method for producing a polarizing film by subjecting a polyvinyl alcohol resin film having a thickness of 1 to 60 ⁇ m to a dyeing treatment, a crosslinking treatment, and a washing treatment in this order.
  • a method for efficiently producing a polarizing film having a good appearance by spraying air alternately on both surfaces of a film while draining it while applying a tension of 200 to 1500 N / m to the film is described.
  • Patent Document 1 attempts to crush and remove foreign matters by calendaring or the like in a state where foreign matters already exist on the transparent support or the like. Therefore, the foreign matter removal accuracy is not high, and minute foreign matter remains after the removal step. For this reason, the technique described in Patent Document 1 is difficult to apply to a method for manufacturing a thin optical film in which the appearance defect is a problem even when the thickness is particularly thin and minute foreign matter is present. Was the actual situation.
  • the present invention has been completed as a result of taking the above circumstances into consideration, and its purpose is to produce an optical film in which appearance defects due to foreign matters and / or bubbles are prevented even when the optical film is thin. It is to provide a method.
  • the inventors of the present invention adopt a specific coating method when manufacturing an optical film including a laminated structure in which at least two films are bonded to each other.
  • the present inventors have found that foreign matters such as dust and dust that cause appearance defects can be removed by applying a liquid material to the opposite side of each bonding surface of the film.
  • the adhesive composition or pressure-sensitive adhesive composition is applied to the bonding surface of at least one film. It has been found that the removal of foreign substances and / or bubbles and the formation of the adhesive composition layer or the pressure-sensitive adhesive composition layer can be carried out at the same time.
  • the present invention has been obtained as a result of such diligence, and has the following configuration.
  • the present invention provides an optical film including a laminated structure in which at least a first film and a second film are bonded via an adhesive layer or a pressure-sensitive adhesive layer comprising a cured product layer of the adhesive composition or the pressure-sensitive adhesive composition.
  • the side of the first film opposite to the bonding surface with the second film, and the second film of the first film Foreign matter is removed by applying a liquid having a viscosity of 1 to 10000 cP on at least one side of the side opposite to the bonding surface with one film using a gravure roll coating method using a gravure roll.
  • the manufacturing method of the optical film characterized by having a 1st application
  • the foreign substance and / or air bubbles are removed by applying the adhesive composition or the pressure-sensitive adhesive composition to the bonding surface of at least one film using a post-metering application method. It is preferable to have a coating process. According to such a configuration, an adhesive composition or a pressure-sensitive adhesive composition is used while scraping off foreign matters such as dust and dust existing on at least one bonding surface of two films to be bonded using a post-metering coating method. The adhesive composition or the pressure-sensitive adhesive composition is applied while scraping off the gel-like substance and the aggregate derived from the object from the bonding surface. As a result, it is possible to manufacture an optical film in which occurrence of appearance defects due to foreign matters is further prevented.
  • an adhesive composition or a pressure-sensitive adhesive composition is applied to one of the two films, and the other is applied thereto.
  • the film is generally manufactured by laminating the film (hereinafter also referred to as “one-side coating method”).
  • the adhesive (or pressure-sensitive adhesive) coating surface of one film is in direct contact with the bonding surface of the other (no adhesive composition (or pressure-sensitive adhesive composition)) film. Pasted together.
  • the adhesive composition (or the pressure-sensitive adhesive composition) having viscosity is in direct contact with the bonding surface of the other film, air bubbles are easily caught during bonding.
  • the adhesive composition or the pressure-sensitive adhesive composition
  • the adhesive of the first film is bonded while being in contact with the adhesive (or pressure-sensitive adhesive) application surface of the second film. That is, since adhesive compositions (or pressure-sensitive adhesive compositions) having viscosity are bonded together while being overlapped, bubbles are difficult to bite at the time of bonding, and bubbles are easily removed.
  • the adhesive composition (or the pressure-sensitive adhesive composition) is applied to both the bonding surface of the first film and the bonding surface of the second film, compared to the single-side coating method. Also, since it is excellent in terms of the effect of removing bubbles, it is possible to produce an optical film in which appearance defects due to bubbles are prevented.
  • the “post-measuring coating method” means a method for obtaining a predetermined coating film thickness by applying an external force to the liquid film to remove excess liquid.
  • the post-metering coating method include a gravure roll coating method, a forward roll coating method, an air knife coating method, a rod / bar coating method, etc., but from the viewpoints of foreign matter removal accuracy and coating film thickness uniformity
  • the gravure roll coating method using a gravure roll is preferable.
  • “removing foreign matters and / or bubbles” means removing at least one or both of foreign matters and bubbles.
  • the liquid material preferably contains at least 50% by weight of water. If the liquid applied to remove the foreign matter remains in the second application step of applying the adhesive composition (or the pressure-sensitive adhesive composition), there is a possibility of causing poor adhesion (or poor adhesion). Therefore, after the first coating process, the liquid material needs to be removed quickly in a drying process or the like. And it is preferable for the liquid material to contain at least 50% by weight of water because the drying step after applying the liquid material can be simplified.
  • the liquid material further contains an alcohol. According to such a configuration, the wettability (leveling property) of the liquid material itself on the film can be increased, and the evaporation rate of the liquid material can be increased. For this reason, it is preferable because the drying and removal efficiency of the liquid can be further increased, and the productivity is improved.
  • the post-metering application method is a method of applying the adhesive composition or the pressure-sensitive adhesive composition by circulation, and the adhesive composition or the second film is applied from the first film and / or the second film by application. It is preferable to have a foreign matter removing function for removing foreign matters mixed in the pressure-sensitive adhesive composition from the adhesive composition or the pressure-sensitive adhesive composition.
  • a coating liquid composed of an adhesive composition or a pressure-sensitive adhesive composition is applied to the bonding surface of the first film and / or the second film. Or when the foreign material removed from the bonding surface of the 2nd film is included, possibility that a foreign material will exist in the bonding surface of the 1st film after application
  • the coating method used has a foreign matter removing function that removes foreign matter mixed in the adhesive composition or pressure-sensitive adhesive composition from the first film and / or second film by coating from the adhesive composition or pressure-sensitive adhesive composition. If it is provided, the amount of foreign matter in the coating solution can be significantly reduced. Thereby, possibility that a foreign material exists in the bonding surface of the 1st film and 2nd film after application
  • the rotation direction of the gravure roll and the traveling direction of the first film and the second film are opposite to each other.
  • foreign matter such as dust and dust existing on the bonding surface of the first film and the bonding surface of the second film, and further, a gel-like material and an aggregate derived from the adhesive composition or the pressure-sensitive adhesive composition are scraped off. The effect is effectively enhanced, and the appearance defect of the optical film finally obtained can be more effectively prevented.
  • a honeycomb mesh pattern a trapezoid pattern, a lattice pattern, a pyramid pattern, or a diagonal line pattern can be formed.
  • the pattern formed on the surface of the gravure roll is preferably a honeycomb mesh pattern.
  • the cell volume is preferably 1 to 5 cm 3 / m 2 in order to increase the surface accuracy of the coated surface after application of the adhesive composition or pressure-sensitive adhesive composition, and 2 to 3 cm 3 / m. 2 is preferable.
  • the number of cell lines per roll is preferably 200 to 3000 lines / inch in order to increase the surface accuracy of the coated surface after application of the adhesive composition or pressure-sensitive adhesive composition.
  • the rotation speed ratio of the gravure roll with respect to the traveling speed of the first film and the second film is preferably 100 to 300%.
  • the thickness of the adhesive layer (or the pressure-sensitive adhesive layer) and further the total thickness of the optical film are larger, the foreign matter is less likely to be visually recognized, and the appearance defect tends to be less problematic.
  • the thinner the adhesive layer (or pressure-sensitive adhesive layer), and the thinner the total thickness of the optical film the easier it is to visually recognize foreign matter, and as a result, appearance defects become a problem.
  • an optical film having a very low incidence of foreign matters in the adhesive layer (or pressure-sensitive adhesive layer) can be produced.
  • the production method according to the present invention is particularly useful when the method for producing a particularly large polarizing film, specifically, when the first film is a polarizer and the second film is a transparent protective film.
  • the polarizer as the first film is sequentially conveyed to the polarizer manufacturing process and then the first and second processes while in contact with the roll.
  • a polarizer is manufactured by appropriately immersing and treating a polyvinyl alcohol (PVA) layer as a polarizer raw material in a boric acid bath or a potassium iodide bath.
  • PVA layers transported from each bath use pinch rolls, bar coaters, etc. to remove the excess water adhering to them, but in some cases boric acid or potassium iodide, which is a component in the bath, is precipitated and polarized.
  • a thin polarizer having a thickness of 10 ⁇ m or less is generally manufactured in a state of being laminated with a base film such as polyethylene terephthalate (PET) (in a state of being a laminate of a polarizer having a thickness of 10 ⁇ m or less and a base film).
  • PET polyethylene terephthalate
  • the present inventors have prevented the occurrence of surface flaws on the surface of the polarizer, particularly by removing boric acid or potassium iodide attached to the base film side surface of the laminate, It has been found that the appearance defects can be effectively suppressed.
  • the first film is a laminate in which the polarizer is laminated on a base film, and the liquid crystal is provided on the base film side surface with the polarizer side surface as a bonding surface. It is preferred that the object is applied. According to this configuration, a liquid having a viscosity of 1 to 10000 cP is applied to the side surface of the base film using the gravure roll coating method with the polarizer side surface as the bonding surface, and thus the boron existing on this surface is coated. Foreign substances such as dust and dust can be further removed while effectively removing acid and potassium iodide.
  • the present invention also relates to an optical film produced by any one of the production methods described above, and further to an image display device using the optical film described above.
  • the optical film manufacturing method according to the present invention is particularly problematic in appearance defects due to foreign matters, an optical film having a thin adhesive layer, an optical film having a thin total thickness, particularly a thin polarizing film. This is particularly effective as a manufacturing method.
  • the manufacturing method of the optical film which concerns on this invention is the 1st film of the opposite side of the bonding surface with a 2nd film of a 1st film, and the 2nd film before bonding a 1st film and a 2nd film.
  • a liquid material having a viscosity of 1 to 10000 cP is applied to at least one surface of the side opposite to the bonding surface with a gravure roll coating method.
  • FIG. 1 shows an example of a schematic diagram of a method for producing an optical film according to the present invention.
  • the first coating step X but also the second coating step Y is a gravure coating method.
  • coating system which uses a roll is shown.
  • the liquid material applied to the opposite side of the bonding surface of the first film 1 using the gravure roll coating method 10A is used to remove foreign substances present on the bonding surfaces of the two films to be bonded together.
  • the one having a viscosity of 1 to 10000 cP is used.
  • the liquid material contains water as a main component, specifically, preferably contains at least 50% by weight or more of water, more preferably contains 60% by weight or more, It is more preferable to use those containing 70% by weight or more.
  • the liquid material contains 50 to 100% by weight of water. Further, it preferably contains 0 to 50% by weight of alcohol, and particularly preferably contains 50 to 70% by weight of water and 30 to 50% by weight of alcohol.
  • the 1st film 1 is the laminated body by which the polarizer 11 was laminated
  • the liquid material is not applied to the opposite surface of the second film (transparent protective film) 2 to the bonding surface with the polarizer 11, but in the present invention, the liquid material is also applied to this surface. You may apply.
  • a laminate in which a polarizer 11 is laminated on a base film 12 is used as the first film 1, and in a polarizer manufacturing process, a boric acid bath or a potassium iodide bath (in FIG. 1).
  • a boric acid bath or a potassium iodide bath in FIG. 1
  • the first film 1 is conveyed to the first coating step X.
  • the base film 12 is designed to be positioned on the gravure roll side included in the gravure roll coating method 10A
  • the polarizer 11 is designed to be positioned on the opposite side of the gravure roll included in the gravure roll coating method 10A.
  • the first film 1 is conveyed in the right direction in FIG.
  • a drying step for drying and removing the liquid material may be provided as necessary.
  • a drying method known to those skilled in the art can be used.
  • the first film 1 conveyed to the second step Y is coated with the adhesive composition 3 on the side surface of the polarizer 11 of the first film 1 using a gravure roll coating method.
  • the gravure roll provided in the gravure coating method 10B is rotated clockwise while being conveyed in the right direction in FIG. That is, the rotation direction of the gravure roll and the traveling direction of the first film 1 are opposite to each other.
  • the rotation direction of the gravure roll and the traveling direction of the second film 2 are opposite to each other.
  • the effect of scraping off foreign matters such as dust and dust existing on the bonding surface of the first film 1 and the bonding surface of the second film 2, and further the gel-like material and aggregate derived from the adhesive composition is effective.
  • the appearance defect of the optical film finally obtained can be prevented more effectively.
  • the rotation speed of the gravure roll with respect to the traveling speed of the first film 1 and the second film 2 is 100 to 300%. Preferably, it is 150 to 250%.
  • FIG. 2 shows an example of a schematic diagram of a gravure roll coating method, which is a post-metering coating method used in the present invention.
  • the adhesive composition 3 is applied to the first film 1 using a gravure coating method 10B. It represents the situation.
  • FIG. 2 when the foreign matter is removed while pressing the gravure roll 4 against the first film 1, the foreign matter such as dust and dust existing on the bonding surface of the first film 1, and further, the adhesive composition is derived. It is possible to more effectively remove the gel-like and aggregates.
  • the gravure coating method 10 ⁇ / b> B includes at least a gravure roll 4.
  • a gravure roll On the surface of the gravure roll, an uneven pattern such as a honeycomb mesh pattern, trapezoid pattern, lattice pattern, pyramid pattern or oblique line pattern is formed.
  • a honeycomb mesh pattern is preferably formed, and the cell volume is preferably 1 to 5 cm 3 / m 2. It is preferably 2 to 3 cm 3 / m 2 .
  • the number of cell lines per roll is preferably 200 to 3000 lines / inch in order to increase the surface accuracy of the coated surface after application of the adhesive composition or pressure-sensitive adhesive composition.
  • the uneven pattern of the gravure roll 4 has a function of applying the adhesive composition 3 to the bonding surface of the first film 1 while scooping up the adhesive composition (coating liquid) 3.
  • it is preferably a closed system in which the adhesive coating liquid is not exposed to the outside air.
  • the foreign matter existing on the bonding surface of the first film 1, and further the gel-like substance and aggregate derived from the adhesive composition 3 are scraped off by the gravure roll 4 during the application, and the adhesive It moves in the container 5 containing the composition 3 and may be applied again to the bonding surface of the first film by the gravure roll 4. Therefore, particularly when the post-measuring application method is a method in which the adhesive composition or the pressure-sensitive adhesive composition is circulated and applied, the gravure roll 4 is scraped as the application process of the adhesive composition 3 becomes longer. There is a concern that the amount of accumulated foreign matter and the like taken will increase.
  • the gravure coating method 10B removes foreign matter mixed in the adhesive composition or pressure-sensitive adhesive composition from the first film 1 and / or the second film 2 by coating from the adhesive composition or pressure-sensitive adhesive composition.
  • the amount of foreign matter or the like present in the applied adhesive composition 3 is always kept at a very small amount or zero. Therefore, finally, the generation amount of foreign matters and the like on the bonding surface of the first film 1 can be extremely reduced.
  • the foreign matter removing function includes a filter, a distillation apparatus, and centrifugal separation.
  • the filter 7 can be arranged on the downstream side of the pump function 8 as shown in FIG.
  • the filter 7 can also be arrange
  • the mesh size of the filter 7 can be appropriately changed depending on the material of the first film 1 and the second film, the blending design of the adhesive composition 3, and the like, preferably 10 ⁇ m or less, and more preferably 5 ⁇ m or less.
  • the adhesive composition 3 may be circulated using a tank 6 or the like as shown in FIG. 2, or the adhesive composition 3 after being applied by the gravure roll 4 may be discarded.
  • the gravure coating method 10A used in the first coating process X for applying a liquid material can adopt the same method as the gravure coating method 10B.
  • the adhesive composition 3 is applied to the bonding surface of the first film 1 and / or the bonding surface of the second film 2 in the second application step by the application method of the post-metering application method shown in FIG.
  • the 1st film 1 and the 2nd film 2 are bonded using the nip roll 9 through an adhesive composition (adhesive layer).
  • the line speed of the first film and / or the second film depends on the curing time of the adhesive composition (or the pressure-sensitive adhesive composition), but is preferably 1 to 500 m / min. Preferably, it is 5 to 300 m / min, and more preferably 10 to 100 m / min. If the line speed is too low, the productivity is poor, or the damage to the first film / and / or the second film is too great to produce an optical film that can withstand a durability test. If the line speed is too high, the adhesive composition may not be sufficiently cured, and the target adhesiveness may not be obtained.
  • Such an optical film includes a laminated structure in which at least a first film and a second film are bonded via an adhesive layer or an adhesive layer composed of a cured product layer of an adhesive composition or an adhesive composition.
  • the adhesive layer or the pressure-sensitive adhesive layer is not particularly limited as long as it is optically transparent, and water-based, solvent-based, hot-melt, and radical-curing types are used.
  • a transparent curable adhesive layer is suitable.
  • a radical curable adhesive is suitably used as the adhesive composition.
  • the radical curable adhesive include active energy ray curable adhesives such as an electron beam curable adhesive and an ultraviolet curable adhesive.
  • an active energy ray curable adhesive that can be cured in a short time is preferable, and an ultraviolet curable adhesive that can be cured with low energy is more preferable.
  • UV curing adhesives can be broadly classified into radical polymerization curing adhesives and cationic polymerization adhesives.
  • the radical polymerization curable adhesive can be used as a thermosetting adhesive.
  • curable component of the radical polymerization curable adhesive examples include a compound having a (meth) acryloyl group and a compound having a vinyl group. These curable components may be monofunctional or bifunctional or higher. Moreover, these curable components can be used individually by 1 type or in combination of 2 or more types. As these curable components, for example, compounds having a (meth) acryloyl group are suitable.
  • the compound having a (meth) acryloyl group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and 2-methyl-2-nitro.
  • Examples of the compound having a (meth) acryloyl group include cycloalkyl (meth) acrylate (for example, cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, etc.), aralkyl (meth) acrylate (for example, benzyl (meth)).
  • cycloalkyl (meth) acrylate for example, cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, etc.
  • aralkyl (meth) acrylate for example, benzyl (meth)
  • Acrylates polycyclic (meth) acrylates (eg 2-isobornyl (meth) acrylate, 2-norbornylmethyl (meth) acrylate, 5-norbornen-2-yl-methyl (meth) acrylate, 3-methyl -2-norbornylmethyl (meth) acrylate, etc.), hydroxyl group-containing (meth) acrylic acid esters (eg, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2,3-dihydroxypropylmethyl) -Butyl (meth) methacrylate), alkoxy group or phenoxy group-containing (meth) acrylic acid esters (2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-methoxymethoxyethyl (meth) acrylate) , 3-methoxybutyl (meth) acrylate, ethyl carbitol (
  • Examples of compounds having a (meth) acryloyl group other than the above include amide group-containing monomers such as hydroxyethyl acrylamide, N-methylol acrylamide, N-methoxymethyl acrylamide, N-ethoxymethyl acrylamide, and (meth) acrylamide. It is done. Moreover, nitrogen-containing monomers, such as acryloyl morpholine, etc. are mentioned.
  • Examples of the curable component of the radical polymerization curable adhesive include compounds having a plurality of polymerizable double bonds such as a (meth) acryloyl group and a vinyl group, and the compound can be used as a crosslinking component. It can also be mixed with the adhesive component.
  • Examples of the curable component that becomes such a crosslinking component include tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, tricyclodecane dimethanol diacrylate, cyclic trimethylolpropane formal acrylate, dioxane glycol diacrylate, and EO.
  • the radical polymerization curable adhesive contains the curable component, and in addition to the component, a radical polymerization initiator is added according to the type of curing.
  • a radical polymerization initiator is added according to the type of curing.
  • An agent is used.
  • the amount of the radical polymerization initiator used is usually about 0.1 to 10 parts by weight, preferably 0.5 to 3 parts by weight per 100 parts by weight of the curable component.
  • the radical polymerization curable adhesive may be added with a photosensitizer that increases the curing speed and sensitivity of the electron beam typified by a carbonyl compound, if necessary.
  • the amount of the photosensitizer used is usually about 0.001 to 10 parts by weight, preferably 0.01 to 3 parts by weight per 100 parts by weight of the curable component.
  • Examples of the curable component of the cationic polymerization curable adhesive include compounds having an epoxy group or an oxetanyl group.
  • the compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used.
  • a preferable epoxy compound a compound having at least two epoxy groups and at least one aromatic ring in the molecule, or at least two epoxy groups in the molecule, at least one of which has an alicyclic ring. Examples thereof include a compound formed between two adjacent carbon atoms constituting it.
  • examples of the water-based curable adhesive include vinyl polymer, gelatin, vinyl latex, polyurethane, isocyanate, polyester, and epoxy.
  • Such an adhesive layer composed of an aqueous adhesive can be formed as an aqueous solution coating / drying layer, etc., but when preparing the aqueous solution, a catalyst such as a crosslinking agent, other additives, and an acid can be used as necessary. Can be blended.
  • the water-based adhesive is preferably an adhesive containing a vinyl polymer
  • the vinyl polymer is preferably a polyvinyl alcohol resin.
  • the adhesive agent containing the polyvinyl alcohol-type resin which has an acetoacetyl group is more preferable from the point which improves durability.
  • the compound which has at least two functional groups reactive with a polyvinyl alcohol-type resin can be used preferably.
  • boric acid and borax carboxylic acid compounds, alkyl diamines; isocyanates; epoxies; monoaldehydes; dialdehydes; amino-formaldehyde resins; and divalent or trivalent metal salts and oxides thereof Is mentioned.
  • the adhesive that forms the curable adhesive layer may contain an additive as necessary.
  • additives include coupling agents such as silane coupling agents and titanium coupling agents, adhesion promoters typified by ethylene oxide, additives that improve wettability with transparent films, acryloxy group compounds and hydrocarbons (Natural and synthetic resins) and other additives that improve mechanical strength and processability, UV absorbers, anti-aging agents, dyes, processing aids, ion trapping agents, antioxidants, tackifiers, Stabilizers such as fillers (other than metal compound fillers), plasticizers, leveling agents, foaming inhibitors, antistatic cracks, heat stabilizers, hydrolysis stabilizers, and the like.
  • the thickness of the transparent curable adhesive layer is preferably 0.01 to 10 ⁇ m. More preferably, it is 0.1 to 5 ⁇ m, and still more preferably 0.3 to 4 ⁇ m. Since the height between each film layer of appearance defects due to foreign matters or bubbles is generally several ⁇ m (about 2 to 5 ⁇ m), if the thickness of the adhesive layer is 2 ⁇ m or less, the problem of appearance defects is significant. Become. However, since the optical film manufacturing method according to the present invention can prevent appearance defects, it is particularly useful as a method for manufacturing an optical film having an adhesive layer thickness of 2 ⁇ m or less.
  • the pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive.
  • Various pressure-sensitive adhesives can be used as the pressure-sensitive adhesive, such as rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, vinyl alkyl ether-based pressure-sensitive adhesives, polyvinylpyrrolidone-based pressure-sensitive adhesives, Examples include acrylamide-based adhesives and cellulose-based adhesives.
  • An adhesive base polymer is selected according to the type of the adhesive.
  • acrylic pressure-sensitive adhesives are preferably used because they are excellent in optical transparency, exhibit appropriate wettability, cohesiveness, and adhesive pressure-sensitive adhesive properties, and are excellent in weather resistance and heat resistance.
  • the radical polymerization curable adhesive can be used in an electron beam curable type or an ultraviolet curable type.
  • the acceleration voltage is preferably 5 kV to 300 kV, and more preferably 10 kV to 250 kV. If the acceleration voltage is less than 5 kV, the electron beam may not reach the adhesive and may be insufficiently cured. If the acceleration voltage exceeds 300 kV, the penetration force through the sample is too strong and damages the transparent protective film and the polarizer. There is a risk of giving.
  • the irradiation dose is 5 to 100 kGy, more preferably 10 to 75 kGy.
  • the adhesive becomes insufficiently cured, and when it exceeds 100 kGy, the transparent protective film and the polarizer are damaged, resulting in a decrease in mechanical strength and yellowing, thereby obtaining predetermined optical characteristics. I can't.
  • the electron beam irradiation is usually performed in an inert gas, but if necessary, it may be performed in the atmosphere or under a condition where a little oxygen is introduced. Depending on the material of the transparent protective film, by appropriately introducing oxygen, the transparent protective film surface where the electron beam first hits can be obstructed to prevent oxygen damage and prevent damage to the transparent protective film. An electron beam can be irradiated efficiently.
  • the ultraviolet curable type when adopted in the present invention, it is preferable to use a device that does not emit light having a wavelength shorter than 380 nm as the ultraviolet ray generating device, and more specifically, the integrated illuminance and wavelength in the wavelength range of 380 to 440 nm.
  • the ratio with the integrated illuminance in the range of 250 to 370 nm is preferably 100: 0 to 100: 50, and more preferably 100: 0 to 100: 40.
  • a gallium-filled metal halide lamp and an LED light source that emits light in the wavelength range of 380 to 440 nm are preferable.
  • low pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, ultra high pressure mercury lamp, incandescent lamp, xenon lamp, halogen lamp, carbon arc lamp, metal halide lamp, fluorescent lamp, tungsten lamp, gallium lamp, excimer laser or sunlight as the light source It is also possible to use a light having a wavelength shorter than 380 nm by using a band pass filter.
  • the first film and / or the second film can be used without particular limitation as long as it is a transparent optical film.
  • the greater the thickness of the adhesive layer (or the pressure-sensitive adhesive layer) and the greater the total thickness of the optical film the more difficult it is to visually recognize foreign matter, and the appearance defects tend to be less problematic.
  • the thinner the adhesive layer (or pressure-sensitive adhesive layer), and the thinner the total thickness of the optical film the easier it is to visually recognize foreign matter, and as a result, appearance defects become a problem. There are many cases.
  • an optical film having a very low incidence of foreign matters in the adhesive layer (or pressure-sensitive adhesive layer) can be produced.
  • the manufacturing method according to the present invention is particularly useful when the manufacturing method of a particularly large polarizing film, specifically, when the first film is a transparent protective film and the second film is a polarizer.
  • the production method according to the present invention even in the case of producing a thin polarizing film, particularly when the polarizer has a thickness of 10 ⁇ m or less, in the adhesive layer (or the pressure-sensitive adhesive layer), foreign matter or This is preferable because a thin polarizing film in which the occurrence of appearance defects due to bubbles can be prevented can be produced.
  • the first film and / or the second film may be subjected to a surface modification treatment before applying the active energy ray-curable adhesive composition.
  • a surface modification treatment include corona treatment, plasma treatment, and saponification treatment.
  • the first film and the second film are preferably bonded via an adhesive layer formed by a cured product layer of the radical polymerization curable adhesive composition.
  • an easy-adhesion layer can be provided between the first film and the second film.
  • the easy adhesion layer can be formed of, for example, various resins having a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone-based, a polyamide skeleton, a polyimide skeleton, a polyvinyl alcohol skeleton, and the like. These polymer resins can be used alone or in combination of two or more. Moreover, you may add another additive for formation of an easily bonding layer. Specifically, a stabilizer such as a tackifier, an ultraviolet absorber, an antioxidant, and a heat resistance stabilizer may be used.
  • the easy-adhesion layer is formed by applying and drying a material for forming an easy / BR> layer on the film by a known technique.
  • the material for forming the easy-adhesion layer is usually adjusted as a solution diluted to an appropriate concentration in consideration of thickness after drying, smoothness of application, and the like.
  • the thickness of the easy-adhesion layer after drying is preferably 0.01 to 5 ⁇ m, more preferably 0.02 to 2 ⁇ m, and still more preferably 0.05 to 1 ⁇ m. Note that a plurality of easy-adhesion layers can be provided, but also in this case, the total thickness of the easy-adhesion layers is preferably in the above range.
  • a polarizing film including a laminated structure in which at least a first film and a second film are bonded is, for example, in FIG. 1, a first film 1 that is a laminate of a polarizer 11 and a base film 12, and a transparent protective film. It can manufacture by sticking together the certain 2nd film 1 through the adhesive bond layer which consists of a hardened
  • the thickness of the first film and the second film is preferably 60 ⁇ m or less, More preferably, it is 40 ⁇ m or less.
  • the total thickness of the polarizing film is 100 ⁇ m or less, since the thickness is thin, appearance defects due to foreign matters in the adhesive layer often become a problem.
  • an optical film in which the generation of foreign matters in the adhesive layer can be effectively prevented can be manufactured. Therefore, when manufacturing a thin polarizing film having a total thickness of 100 ⁇ m or less, particularly Is suitable for producing a thin polarizing film having a total thickness of 50 ⁇ m or less.
  • a thin polarizing film in the present invention it is possible to effectively prevent appearance defects even when producing a thin polarizing film including a thin polarizer having a thickness of 10 ⁇ m or less.
  • the polarizer is not particularly limited, and various types can be used.
  • the polarizer include hydrophilic polymer films such as polyvinyl alcohol film, partially formalized polyvinyl alcohol film, and ethylene / vinyl acetate copolymer partially saponified film, and two colors such as iodine and dichroic dye.
  • polyene-based oriented films such as those obtained by adsorbing a functional material and uniaxially stretched, polyvinyl alcohol dehydrated products and polyvinyl chloride dehydrochlorinated products.
  • a polarizer composed of a polyvinyl alcohol film and a dichroic material such as iodine is preferable.
  • the thickness of these polarizers is not particularly limited, but is generally about 80 ⁇ m or less.
  • a polarizer obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching it can be produced, for example, by dyeing polyvinyl alcohol in an aqueous iodine solution and stretching it 3 to 7 times the original length. If necessary, it can be immersed in an aqueous solution of boric acid or potassium iodide. Further, if necessary, the polyvinyl alcohol film may be immersed in water and washed before dyeing. In addition to washing the polyvinyl alcohol film surface with dirt and anti-blocking agents by washing the polyvinyl alcohol film with water, it also has the effect of preventing unevenness such as uneven coloring by swelling the polyvinyl alcohol film. is there.
  • 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.
  • a thin polarizer having a thickness of 10 ⁇ m or less can be used. From the viewpoint of thinning, the thickness is preferably 1 to 7 ⁇ m. Such a thin polarizer is preferable in that the thickness unevenness is small, the visibility is excellent, the dimensional change is small, the durability is excellent, and the thickness of the polarizing film can be reduced.
  • the thin polarizer typically, JP-A-51-069644, JP-A-2000-338329, WO2010 / 100917, PCT / JP2010 / 001460, or Japanese Patent Application No. 2010- And a thin polarizer described in Japanese Patent Application No. 269002 and Japanese Patent Application No. 2010-263692.
  • These thin polarizers can be obtained by a production method including a step of stretching and dyeing a polyvinyl alcohol-based resin (hereinafter also referred to as PVA-based resin) layer and a stretching resin base material in a laminated state. With this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without problems such as breakage due to stretching by being supported by the stretching resin substrate.
  • PVA-based resin polyvinyl alcohol-based resin
  • the thin polarizers among the production methods including the step of stretching in the state of a laminate and the step of dyeing, WO2010 / 100917 pamphlet, PCT / PCT / PCT / JP 2010/001460 specification, or Japanese Patent Application No. 2010-269002 and Japanese Patent Application No. 2010-263692, the one obtained by a production method including a step of stretching in a boric acid aqueous solution is preferable. What is obtained by the manufacturing method including the process of extending
  • the thin high-performance polarizer described in the specification of the above PCT / JP2010 / 001460 is a thin film having a thickness of 7 ⁇ m or less made of a PVA-based resin oriented with a dichroic material, which is integrally formed on a resin substrate. It is a high-functional polarizer and has optical properties such as a single transmittance of 42.0% or more and a polarization degree of 99.95% or more.
  • the thin high-performance polarizer generates a PVA-based resin layer by applying and drying a PVA-based resin on a resin substrate having a thickness of at least 20 ⁇ m, and the generated PVA-based resin layer is used as a dichroic dyeing solution. So that the dichroic substance is adsorbed on the PVA resin layer, and the PVA resin layer on which the dichroic substance is adsorbed is integrated with the resin base material in the boric acid aqueous solution so that the total draw ratio is the original length. It can manufacture by extending
  • a method for producing a laminate film including a thin high-functional polarizer in which a dichroic material is oriented and includes a resin substrate having a thickness of at least 20 ⁇ m and a PVA resin on one side of the resin substrate.
  • surface of the resin base material A step of adsorbing the dichroic substance to the PVA resin layer contained in the laminate film by immersing the film in a dye solution containing the dichroic substance, and a PVA resin adsorbing the dichroic substance
  • the above-mentioned Japanese Patent Application Nos. 2010-269002 and 2010-263692 are thin polarizers, which are continuous web polarizers made of a PVA-based resin in which a dichroic material is oriented, and are amorphous esters.
  • a laminate including a PVA-based resin layer formed on a thermoplastic resin base material is stretched in a two-stage stretching process consisting of air-assisted stretching and boric acid-water stretching to a thickness of 10 ⁇ m or less. It is.
  • Such a thin polarizer has P> ⁇ (100.929T ⁇ 42.4-1) ⁇ 100 (where T ⁇ 42.3) and P ⁇ 99, where T is the single transmittance and P is the polarization degree. .9 (where T ⁇ 42.3) is preferable.
  • the thin polarizer is a stretch intermediate composed of an oriented PVA resin layer by high-temperature stretching in the air with respect to a PVA resin layer formed on an amorphous ester thermoplastic resin substrate of a continuous web.
  • a colored intermediate product comprising a PVA-based resin layer in which a dichroic material (preferably iodine or a mixture of iodine and an organic dye) is oriented by adsorption of the dichroic material to the stretched intermediate product and a step of generating the product.
  • a thin polarizer comprising a step of generating a product, and a step of generating a polarizer having a thickness of 10 ⁇ m or less comprising a PVA-based resin layer in which a dichroic material is oriented by stretching in a boric acid solution with respect to a colored intermediate product It can be manufactured by a manufacturing method.
  • the total draw ratio of the PVA resin layer formed on the amorphous ester thermoplastic resin base material by high-temperature drawing in air and drawing in boric acid solution should be 5 times or more. desirable.
  • stretching can be 60 degreeC or more.
  • the colored intermediate product is added to the aqueous boric acid solution whose liquid temperature does not exceed 40 ° C. It is desirable to do so by dipping.
  • the amorphous ester-based thermoplastic resin base material is amorphous polyethylene containing copolymerized polyethylene terephthalate copolymerized with isophthalic acid, copolymerized polyethylene terephthalate copolymerized with cyclohexanedimethanol, or other copolymerized polyethylene terephthalate. It can be terephthalate and is preferably made of a transparent resin, and the thickness thereof can be 7 times or more the thickness of the PVA resin layer to be formed.
  • the draw ratio of high-temperature drawing in the air is preferably 3.5 times or less, and the drawing temperature of high-temperature drawing in the air is preferably not less than the glass transition temperature of the PVA resin, specifically in the range of 95 ° C to 150 ° C.
  • the total stretching ratio of the PVA resin layer formed on the amorphous ester thermoplastic resin base material is preferably 5 to 7.5 times .
  • the total stretching ratio of the PVA-based resin layer formed on the amorphous ester-based thermoplastic resin base material is 5 times or more and 8.5 times or less. Is preferred. More specifically, a thin polarizer can be produced by the following method.
  • a base material for a continuous web of isophthalic acid copolymerized polyethylene terephthalate (amorphous PET) in which 6 mol% of isophthalic acid is copolymerized is prepared.
  • the glass transition temperature of amorphous PET is 75 ° C.
  • a laminate comprising a continuous web of amorphous PET substrate and a polyvinyl alcohol (PVA) layer is prepared as follows. Incidentally, the glass transition temperature of PVA is 80 ° C.
  • a 200 ⁇ m-thick amorphous PET base material and a 4-5% PVA aqueous solution in which PVA powder having a polymerization degree of 1000 or more and a saponification degree of 99% or more are dissolved in water are prepared.
  • an aqueous PVA solution is applied to a 200 ⁇ m thick amorphous PET substrate and dried at a temperature of 50 to 60 ° C. to obtain a laminate in which a 7 ⁇ m thick PVA layer is formed on the amorphous PET substrate. .
  • a thin high-functional polarizer having a thickness of 3 ⁇ m is manufactured from the laminate including the PVA layer having a thickness of 7 ⁇ m through the following steps including a two-step stretching process of air-assisted stretching and boric acid water stretching.
  • the laminate including the 7 ⁇ m-thick PVA layer is integrally stretched with the amorphous PET substrate to produce a stretched laminate including the 5 ⁇ m-thick PVA layer.
  • a laminate including a 7 ⁇ m-thick PVA layer is subjected to a stretching apparatus disposed in an oven set to a stretching temperature environment of 130 ° C. so that the stretching ratio is 1.8 times. Are stretched uniaxially at the free end.
  • the PVA layer contained in the stretched laminate is changed to a 5 ⁇ m thick PVA layer in which PVA molecules are oriented.
  • a colored laminate in which iodine is adsorbed on a 5 ⁇ m-thick PVA layer in which PVA molecules are oriented is generated by a dyeing process.
  • this colored laminate has a single transmittance of the PVA layer constituting the high-performance polarizer finally produced by using the stretched laminate in a dye solution containing iodine and potassium iodide at a liquid temperature of 30 ° C.
  • Iodine is adsorbed to the PVA layer contained in the stretched laminate by dipping for an arbitrary period of time so as to be 40 to 44%.
  • the staining solution uses water as a solvent, and an iodine concentration within the range of 0.12 to 0.30% by weight and a potassium iodide concentration within the range of 0.7 to 2.1% by weight.
  • concentration ratio of iodine and potassium iodide is 1 to 7.
  • potassium iodide is required to dissolve iodine in water. More specifically, by immersing the stretched laminate in a dyeing solution having an iodine concentration of 0.30% by weight and a potassium iodide concentration of 2.1% by weight for 60 seconds, iodine is applied to a 5 ⁇ m-thick PVA layer in which PVA molecules are oriented. A colored laminate is adsorbed on the substrate.
  • the colored laminate is further stretched integrally with the amorphous PET base material by the second stage boric acid water stretching step to produce an optical film laminate including a PVA layer constituting a highly functional polarizer having a thickness of 3 ⁇ m.
  • the optical film laminate is subjected to stretching by applying the colored laminate to a stretching apparatus provided in a treatment apparatus set to a boric acid aqueous solution having a liquid temperature range of 60 to 85 ° C. containing boric acid and potassium iodide. It is stretched uniaxially at the free end so that the magnification is 3.3 times. More specifically, the liquid temperature of the boric acid aqueous solution is 65 ° C.
  • the colored laminate having an adjusted iodine adsorption amount is first immersed in an aqueous boric acid solution for 5 to 10 seconds. After that, the colored laminate is passed as it is between a plurality of sets of rolls with different peripheral speeds, which is a stretching apparatus installed in the processing apparatus, and the stretching ratio can be freely increased to 3.3 times over 30 to 90 seconds. Stretch uniaxially.
  • the PVA layer contained in the colored laminate is changed into a PVA layer having a thickness of 3 ⁇ m in which the adsorbed iodine is oriented higher in one direction as a polyiodine ion complex.
  • This PVA layer constitutes a high-functional polarizer of the optical film laminate.
  • the optical film laminate was removed from the boric acid aqueous solution and adhered to the surface of the 3 ⁇ m-thick PVA layer formed on the amorphous PET substrate by the washing step. It is preferable to wash boric acid with an aqueous potassium iodide solution. Thereafter, the washed optical film laminate is dried by a drying process using hot air at 60 ° C.
  • the cleaning process is a process for eliminating appearance defects such as boric acid precipitation.
  • an adhesive is applied to the surface of a 3 ⁇ m-thick PVA layer formed on an amorphous PET substrate by a bonding and / or transfer process.
  • the amorphous PET substrate can be peeled off, and the 3 ⁇ m thick PVA layer can be transferred to the 80 ⁇ m thick triacetyl cellulose film.
  • the manufacturing method of said thin polarizer may contain another process other than the said process.
  • examples of other steps include an insolubilization step, a crosslinking step, and a drying (adjustment of moisture content) step.
  • the other steps can be performed at any appropriate timing.
  • the insolubilization step is typically performed by immersing the PVA resin layer in a boric acid aqueous solution. By performing the insolubilization treatment, water resistance can be imparted to the PVA resin layer.
  • the concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water.
  • the liquid temperature of the insolubilizing bath (boric acid aqueous solution) is preferably 20 ° C. to 50 ° C.
  • the insolubilization step is performed after the laminate is manufactured and before the dyeing step and the underwater stretching step.
  • the crosslinking step is typically performed by immersing the PVA resin layer in an aqueous boric acid solution.
  • the concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water.
  • blend iodide it is preferable to mix
  • the blending amount of iodide is preferably 1 to 5 parts by weight with respect to 100 parts by weight of water. Specific examples of the iodide are as described above.
  • the liquid temperature of the crosslinking bath is preferably 20 ° C. to 50 ° C.
  • the crosslinking step is performed before the second boric acid aqueous drawing step.
  • the dyeing step, the crosslinking step, and the second boric acid aqueous drawing step are performed in this order.
  • the material for forming the transparent protective film provided on one or both sides of the polarizer is preferably a material excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy and the like.
  • polyester polymers such as polyethylene terephthalate and polyethylene naphthalate
  • cellulose polymers such as diacetyl cellulose and triacetyl cellulose
  • acrylic polymers such as polymethyl methacrylate
  • styrene such as polystyrene and acrylonitrile / styrene copolymer (AS resin)
  • AS resin acrylonitrile / styrene copolymer
  • polyethylene, polypropylene, polyolefins having a cyclo or norbornene structure polyolefin polymers such as ethylene / propylene copolymers, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamide, imide polymers, sulfone polymers , Polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy polymer, or the above
  • the polymer that forms the transparent protective film include polymer blends. One or more kinds of arbitrary appropriate additives may be contained in the transparent protective film.
  • the additive examples include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, an anti-coloring agent, a flame retardant, a nucleating agent, an antistatic agent, a pigment, and a coloring agent.
  • the content of the thermoplastic resin in the transparent protective film is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, still more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. .
  • content of the said thermoplastic resin in a transparent protective film is 50 weight% or less, there exists a possibility that the high transparency etc. which a thermoplastic resin originally has cannot fully be expressed.
  • the transparent protective film examples include a polymer film described in JP-A-2001-343529 (WO01 / 37007), for example, (A) a thermoplastic resin having a substituted and / or unsubstituted imide group in the side chain, B) Resin compositions containing a thermoplastic resin having substituted and / or unsubstituted phenyl and nitrile groups in the side chain.
  • Specific examples include a film of a resin composition containing an alternating copolymer composed of isobutylene and N-methylmaleimide and an acrylonitrile / styrene copolymer.
  • As the film a film made of a mixed extruded product of the resin composition or the like can be used. Since these films have a small phase difference and a small photoelastic coefficient, problems such as unevenness due to the distortion of the polarizing film can be eliminated, and since the moisture permeability is small, the humidification durability is excellent.
  • the thickness of the transparent protective film can be determined as appropriate, but is generally about 1 to 500 ⁇ m from the viewpoints of workability such as strength and handleability and thin layer properties. In particular, 20 to 80 ⁇ m is preferable, and 30 to 60 ⁇ m is more preferable.
  • the transparent protective film which consists of the same polymer material may be used by the front and back, and the transparent protective film which consists of a different polymer material etc. may be used.
  • Functional surfaces such as a hard coat layer, an antireflection layer, an antisticking layer, a diffusion layer or an antiglare layer can be provided on the surface of the transparent protective film to which the polarizer is not adhered.
  • the functional layers such as the hard coat layer, antireflection layer, antisticking layer, diffusion layer and antiglare layer can be provided on the transparent protective film itself, and separately provided separately from the transparent protective film. You can also.
  • the polarizing film of the present invention can be used as an optical film laminated with another optical layer in practical use.
  • the optical layer is not particularly limited.
  • a liquid crystal display device such as a reflection plate, a semi-transmission plate, a retardation plate (including wavelength plates such as 1/2 and 1/4), and a viewing angle compensation film.
  • One or more optical layers that may be used can be used.
  • a reflective polarizing film or semi-transmissive polarizing film in which a polarizing plate or a semi-transmissive reflecting plate is further laminated on the polarizing film of the present invention an elliptical polarizing film or circularly polarizing film in which a retardation film is further laminated on a polarizing film.
  • a wide viewing angle polarizing film obtained by further laminating a viewing angle compensation film on a film or a polarizing film, or a polarizing film obtained by further laminating a brightness enhancement film on the polarizing film is preferred.
  • An optical film obtained by laminating the above optical layer on a polarizing film can be formed by a method of sequentially laminating separately in the manufacturing process of a liquid crystal display device or the like. It is excellent in stability and assembly work, and has the advantage of improving the manufacturing process of a liquid crystal display device and the like.
  • an appropriate adhesive means such as a pressure-sensitive adhesive layer can be used.
  • their optical axes can be set at an appropriate arrangement angle in accordance with the target retardation characteristics.
  • a pressure-sensitive adhesive layer for adhering to other members such as a liquid crystal cell can be provided on the polarizing film described above or an optical film in which at least one polarizing film is laminated.
  • the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer is not particularly limited.
  • an acrylic polymer, a silicone-based polymer, a polyester, a polyurethane, a polyamide, a polyether, a fluorine-based or rubber-based polymer is appropriately used as a base polymer. It can be selected and used.
  • those having excellent optical transparency such as an acrylic pressure-sensitive adhesive, exhibiting appropriate wettability, cohesiveness, and adhesive pressure-sensitive adhesive properties, and being excellent in weather resistance, heat resistance and the like can be preferably used.
  • the pressure-sensitive adhesive layer can be provided on one side or both sides of a polarizing film or an optical film as a superimposed layer of different compositions or types. Moreover, when providing in both surfaces, it can also be set as adhesive layers, such as a different composition, a kind, and thickness, in the front and back of a polarizing film or an optical film.
  • the thickness of the pressure-sensitive adhesive layer can be appropriately determined according to the purpose of use and adhesive force, and is generally 1 to 500 ⁇ m, preferably 1 to 200 ⁇ m, and particularly preferably 1 to 100 ⁇ m.
  • the exposed surface of the adhesive layer is temporarily covered with a separator for the purpose of preventing contamination until it is put to practical use. Thereby, it can prevent contacting an adhesive layer in the usual handling state.
  • a separator for example, an appropriate thin leaf body such as a plastic film, rubber sheet, paper, cloth, non-woven fabric, net, foamed sheet, metal foil, or a laminate thereof, and a silicone-based or long sheet as necessary.
  • an appropriate release agent such as a chain alkyl type, fluorine type or molybdenum sulfide, can be used.
  • the polarizing film or optical film of the present invention can be preferably used for forming various devices such as a liquid crystal display device.
  • the liquid crystal display device can be formed according to the conventional method. That is, a liquid crystal display device is generally formed by appropriately assembling components such as a liquid crystal cell, a polarizing film or an optical film, and an illumination system as necessary, and incorporating a drive circuit. There is no limitation in particular except the point which uses the polarizing film or optical film by invention, and it can apply according to the former.
  • the liquid crystal cell any type such as a TN type, an STN type, or a ⁇ type can be used.
  • liquid crystal display devices such as a liquid crystal display device in which a polarizing film or an optical film is disposed on one side or both sides of a liquid crystal cell, or a backlight or a reflector used in an illumination system can be formed.
  • the polarizing film or optical film by this invention can be installed in the one side or both sides of a liquid crystal cell.
  • polarizing film or an optical film on both sides they may be the same or different.
  • liquid crystal display device for example, a single layer or a suitable layer such as a diffusing plate, an antiglare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffusing plate, a backlight, etc. Two or more layers can be arranged.
  • Parts by weight in the composition means the number of parts when the total amount of the composition is 100 parts by weight.
  • Adjustment of adhesive composition ⁇ Adjustment of active energy ray-curable adhesive composition> HEAA (hydroxyethyl acrylamide) [manufactured by Kojin Co., Ltd.] 38.5 parts by weight, Aronix M-220 (tripropylene glycol diacrylate) [manufactured by Toagosei Co., Ltd.] 20.0 parts by weight, ACMO (acryloylmorpholine) [Kojinsha 38.5 parts by weight, KAYACURE DETX-S (diethylthioxanthone) [manufactured by Nippon Kayaku Co., Ltd.], 1.5 parts by weight, IRGACURE907 (2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane- 1-On) 1.5 parts by weight [manufactured by BASF] was mixed and stirred at 50 ° C. for 1 hour to obtain an active energy ray-curable adhesive.
  • HEAA hydroxyethyl acrylamide
  • the PVA molecules of the PVA layer formed on the amorphous PET base film by such two-stage stretching are oriented in higher order, and the iodine adsorbed by dyeing is oriented in one direction as a polyiodine ion complex. It was possible to produce an optical film laminate (first film (total thickness 40 ⁇ m)) including a PVA layer having a thickness of 5 ⁇ m, constituting the thin polarizer.
  • a transparent protective film made of a (meth) acrylic resin having a lactone ring structure was used.
  • Example 1 In the line shown in FIGS. 1 and 2, a gravure roll coating method 10A including a gravure roll 4 (both MCD coater (manufactured by Fuji Machinery Co., Ltd.)) (cell shape: honeycomb mesh pattern, number of gravure roll cell lines: 1000 / inch, By applying a liquid material to the side surface of the PET base film 12 of the first film 1 which is a laminate of the polarizer 11 and the PET base film 12, using a rotational speed ratio of 140%) Foreign matter and bubbles existing on the side surface of the film 12 were removed, and then the adhesive composition 3 was applied to the side surface of the polarizer 11 of the first film and the bonding surface of the second film using the gravure roll coating method 10B.
  • a gravure roll 4 both MCD coater (manufactured by Fuji Machinery Co., Ltd.)
  • cell shape honeycomb mesh pattern
  • number of gravure roll cell lines 1000 / inch
  • the polarizing film was manufactured while removing foreign substances and bubbles by applying the adhesive composition 3.
  • the adhesive composition 3 was a thickness of the adhesive layer after drying. It was applied to the first film and the second film so that 1 [mu] m.
  • the gravure roll coating method 10A and 10B, were used with the foreign matter removing function shown in FIG. 2 (foreign matter removing method using a filter).
  • an ultraviolet ray (gallium filled metal halide lamp) irradiation device Fusion UV Systems, Inc.
  • Light HAMMER10 bulb V bulb Peak illuminance: 1600 mW / cm 2 , integrated dose
  • the adhesive composition 3 was cured using 1000 / mJ / cm 2 (wavelength 380 to 440 nm) to produce an optical film.
  • the illuminance of ultraviolet rays was measured using a Sola-Check system manufactured by Solatell.
  • Examples 2 to 5 and Comparative Examples 1 to 3 An optical film was produced in the same manner as in Example 1 except that the type of film for performing the first coating step, the type of coating method, the viscosity and composition of the liquid were changed to those shown in Table 1. In the bar coater coating method and the air knife coating method, commercially available coating devices were used.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Ophthalmology & Optometry (AREA)
  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Quality & Reliability (AREA)
  • Polarising Elements (AREA)
  • Adhesives Or Adhesive Processes (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Laminated Bodies (AREA)

Abstract

L'objectif de la présente invention est de fournir un procédé de fabrication de film optique avec lequel la génération de défauts d'aspect causés par les substances étrangères et/ou les bulles peut être évitée même si le film optique est mince. L'invention concerne un procédé de fabrication d'un film optique qui comprend une structure stratifiée dans laquelle au moins un premier film et un deuxième film sont fixés l'un à l'autre par l'intermédiaire d'une couche adhésive et/ou une couche adhésive autocollante comprenant une couche de produit durci d'une composition adhésive ou une composition adhésive autocollante, ledit procédé de fabrication de film optique comprenant un premier processus de revêtement pour éliminer les substances étrangères par revêtement d'au moins la surface du premier film opposée à la surface devant être fixée au deuxième film ou la surface du deuxième film opposée à la surface devant être fixée au premier film avec un matériau liquide ayant une viscosité de 1 à 10000 cP au moyen d'un rouleau de gravure avant de fixer le premier film et le deuxième film.
PCT/JP2016/086561 2016-01-15 2016-12-08 Procédé de fabrication de film optique WO2017122470A1 (fr)

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JP2018200447A (ja) * 2017-05-30 2018-12-20 日東電工株式会社 光学フィルムの製造方法
JP7224729B2 (ja) * 2019-04-25 2023-02-20 日東電工株式会社 積層偏光フィルムの製造方法及び積層偏光フィルムの製造装置
JP7292130B2 (ja) 2019-06-28 2023-06-16 日東電工株式会社 偏光子の製造方法及び偏光子の製造装置
WO2021054357A1 (fr) * 2019-09-20 2021-03-25 日東電工株式会社 Procédé de fabrication de membrane de polarisation et procédé de fabrication de film de polarisation
WO2021054356A1 (fr) * 2019-09-20 2021-03-25 日東電工株式会社 Procédé de production de membrane de polarisation et procédé de production de film de polarisation
KR20220063119A (ko) * 2019-09-20 2022-05-17 닛토덴코 가부시키가이샤 편광막의 제조 방법, 및 편광 필름의 제조 방법
CN111605211B (zh) * 2020-06-03 2021-02-09 四川冠辰环保工程有限公司 一种非沥青基自粘胶膜防水卷材制造方法
CN113210212B (zh) * 2021-03-23 2023-07-07 南京万禾科研仪器有限公司 一种基于环境监测的反光条实验样品制备装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015049476A (ja) * 2013-09-04 2015-03-16 日東電工株式会社 光学フィルムの製造方法
WO2015072205A1 (fr) * 2013-11-14 2015-05-21 日東電工株式会社 Procédé de fabrication de film optique, film optique et dispositif d'affichage d'image
JP2015203768A (ja) * 2014-04-14 2015-11-16 大日本印刷株式会社 位相差フィルムの製造方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008180905A (ja) 2007-01-24 2008-08-07 Fujifilm Corp 光学フイルムの製造方法、光学フイルム用支持体、光学フイルム、偏光板及び画像表示装置
JP6462199B2 (ja) 2012-12-04 2019-01-30 住友化学株式会社 偏光フィルム及び偏光板の製造方法
JP6367628B2 (ja) 2014-07-16 2018-08-01 日東電工株式会社 光学フィルムの製造方法、光学フィルムおよび画像表示装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015049476A (ja) * 2013-09-04 2015-03-16 日東電工株式会社 光学フィルムの製造方法
WO2015072205A1 (fr) * 2013-11-14 2015-05-21 日東電工株式会社 Procédé de fabrication de film optique, film optique et dispositif d'affichage d'image
JP2015203768A (ja) * 2014-04-14 2015-11-16 大日本印刷株式会社 位相差フィルムの製造方法

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CN108431650A (zh) 2018-08-21
JP6647875B2 (ja) 2020-02-14
TWI724076B (zh) 2021-04-11
JP2017126038A (ja) 2017-07-20
CN108431650B (zh) 2021-05-25
TW201736146A (zh) 2017-10-16
KR20180103050A (ko) 2018-09-18

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