Functional film inspection method, inspection system, and original roll

Abstract

[Problem] To provide a functional film inspection method and the like, with which it is possible to properly manage defect information of a functional film. [Solution] The present invention comprises: a first step for acquiring functional-film defect information through inspection performed on a long functional film F1 which is bonded to either a long light polarizer or a long optical laminate comprising a light polarizer so as to produce a long polarizing film F2; a second step for printing identification information at a widthwise edge of the functional film at a prescribed interval in the longitudinal direction of the functional film; and a third step for storing the functional-film defect information in association with the identification information.

Description

[Technical field]

[0001] The present invention relates to a method and system for inspecting a long functional film for producing a long polarizing film by bonding the functional film to a long polarizer or a long optical laminate including a polarizer, and a raw roll of the functional film. In particular, the present invention relates to a method and system for inspecting a functional film, and a raw roll of the functional film, which are capable of appropriately managing defect information of the functional film. [Background technology]

[0002] 2. Description of the Related Art Polarizing films have been used in liquid crystal display devices, etc. The polarizing film has a laminated structure in which a functional film is attached to a polarizer or an optical laminate including a polarizer. Examples of the functional film to be attached to the polarizer include a protective film (including a film that also functions as a retardation film) and a retardation film. An example of an optical laminate containing a polarizer is one in which a protective film is laminated on a polarizer. Examples of functional films to be attached to this optical laminate are retardation films, reflective polarizers, antireflection films, conductive films such as ITO films, and window films made of, for example, polyimide. The process for punching out polarizing films of a size appropriate for the intended use from a long polarizing film is, for example, as follows.

[0003] First, a long length of polarizing film transported by a roll-to-roll method is inspected to detect defects present in the polarizing film. If a defect is detected, the position of the defect is marked and the polarizing film is wound up. Polarizing film as a final product (polarizing film after punching) comes in various sizes depending on the user's specifications, but since it can often be used in common as a long polarizing film (original polarizing film roll), original polarizing film rolls are produced in large quantities and polarizing film products of the required size are punched out from the original polarizing film rolls at a later date as needed. When punching polarizing film products, positions where defects exist must be avoided, or polarizing film products that have been marked with a position where a defect exists after punching must be removed as defective products. Therefore, when inspecting a long polarizing film, it is necessary to detect defects and store the positions of the defects as defect information.

[0004] In order to properly manage defect information and increase the yield of polarizing film products, Patent Document 1 proposes a polarizing film inspection method in which identification information (at least information that identifies the longitudinal position of the polarizing film) is printed on the widthwise end of the polarizing film and the defect information is linked to the identification information. According to the inspection method described in Patent Document 1, it is possible to appropriately manage defect information about defects that occur in the polarizing film.

[0005] However, polarizing films have defects that occur not only in the polarizing film produced by laminating a polarizer or an optical laminate containing a polarizer with a functional film, but also in the functional film alone (the functional film before being laminated with a polarizer or an optical laminate). Furthermore, defects that occur in the functional film alone may be difficult to detect even when inspecting the polarizing film. For this reason, functional films may be inspected individually, but conventionally, defect information detected by such inspection has not been appropriately managed.

[0006] When winding up the functional film, knurling may be performed on the widthwise edges of the functional film to create minute projections and recesses by laser engraving in order to prevent misalignment, loosening, blocking, gauge bands, etc. (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 5925609 [Patent Document 2] Patent No. 5578759 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the problems of the conventional technology as described above, and has an objective of providing a functional film inspection method, inspection system, and original film roll that can appropriately manage defect information of functional films. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides The first method is The method includes a first step of inspecting a long functional film to be laminated to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquiring defect information of the functional film, a second step of printing identification information on the widthwise end of the functional film at predetermined intervals in the longitudinal direction of the functional film, and a third step of storing the defect information of the functional film and the identification information in association with each other. fruit , A knurled portion is formed at a width direction end of the functional film, and in the second step, the identification information is printed by an inkjet method at a portion of the functional film corresponding to the knurled portion. The present invention provides a method for inspecting a functional film, comprising the steps of: In addition, the present invention provides a second method for inspecting a functional film, comprising a first step of inspecting a long functional film to be bonded to a long polarizer or a long optical laminate containing a polarizer to produce a long polarizing film, and obtaining defect information of the functional film, a second step of printing identification information on the widthwise end of the functional film at predetermined intervals in the longitudinal direction of the functional film, and a third step of linking and storing the defect information of the functional film and the identification information, wherein a knurled portion is formed on the widthwise end of the functional film, and in the second step, the identification information is printed so that at least a portion of the identification information does not overlap with the portion of the functional film corresponding to the knurled portion.

[0010] In the present invention, the term "defect information" refers to information including at least the position of a defect, and the term "identification information" refers to information including at least information for identifying a position of a functional film in the longitudinal direction. According to the present invention, defect information of a functional film is obtained in a first step, identification information of the functional film is printed in a second step, and the defect information and the identification information are associated with each other and stored in a third step. Therefore, for example, by reading the identification information in the state of a polarizing film in which a functional film is bonded to a polarizer or an optical laminate containing a polarizer, and linking the identification information with the defect information stored in the third step, it is possible to punch out products while avoiding the locations of defects that occurred in the functional film state. It is not necessary to execute the first to third steps in this order. For example, it is also possible to execute the first step after executing the second step.

[0011] In the present invention, the method of printing the identification information on the functional film may be, for example, an inkjet printing method or a laser engraving method. (In the first method, printing is done using the inkjet method) . According to the findings of the inventors, when identification information is printed on both the functional film and the polarizing film, if the identification information printed on the functional film is designated as first identification information and the identification information printed on the polarizing film is designated as second identification information, by printing the first identification information and the second identification information by any of the following methods (1) to (6), the first identification information and the second identification information can be read separately even if they overlap. (1) First identification information: Inkjet method using transparent ink, second identification information: Laser engraving (2) First identification information: Inkjet method using colored ink, second identification information: Laser engraving (3) First identification information: Laser engraving, second identification information: Inkjet method using transparent ink (4) First identification information: Laser engraving, second identification information: Inkjet method using colored ink (5) First identification information: Inkjet method using transparent ink, second identification information: Inkjet method using colored ink (6) First identification information: Inkjet method using colored ink, second identification information: Inkjet method using transparent ink

[0012] Here, when a knurling processing portion is formed at the widthwise end portion of the functional film, if identification information is printed in the area corresponding to the knurling processing portion (the area where the knurling processing portion has been formed or the area where the knurling processing portion is planned to be formed), there is a risk that the identification information will not be able to be read and distinguished from the unevenness of the knurling processing portion. Therefore, after extensive research, the inventors discovered that if identification information is printed by an inkjet method on the area corresponding to the knurled portion, the identification information can be read in distinction from the unevenness of the knurled portion. Therefore, the present invention In the first method When a knurled portion is formed on the width direction end of the functional film, 、 In the second step, the identification information is printed by an inkjet method on a portion of the functional film that corresponds to the knurled portion.

[0013] The first aspect of the present invention In the method, "a portion corresponding to the knurled portion" means a portion where the knurled portion has been formed or a portion where the knurled portion is to be formed. The first aspect of the present invention According to the method, as the present inventors have found, even if the identification information is printed on a portion corresponding to the knurled portion, the identification information can be read separately from the unevenness of the knurled portion. In other words, the defect information and the identification information can be appropriately linked.

[0014] The knurling height of the knurled portion (the difference between the thickness of the convex part of the knurled portion and the thickness of the functional film other than the knurled portion) is, for example, about 2 to 5 μm, and the thickness of the printing when the identification information is printed by the inkjet method is, for example, about 2 to 2.5 μm. Therefore, The first aspect of the present invention If, as in the method described above, identification information is printed in the area corresponding to the knurled portion, the knurling height and the thickness of the printing will overlap and become thick, which may result in problems such as misalignment when the functional film is wound up or the printing disappearing. In order to reduce the above possibility, when a knurled portion is formed at the width direction end of the functional film, As in the second method according to the present invention, In the second step, it is preferable that the identification information is printed such that at least a portion of the identification information does not overlap a portion of the functional film that corresponds to the knurled portion. The second aspect of the present invention According to this method, at least a part of the identification information does not overlap the area corresponding to the knurling processing area, so there are no areas where the knurling height and the thickness of the printing overlap (when the entire identification information does not overlap the area corresponding to the knurling processing area), or there are few areas where the knurling height and the thickness of the printing overlap (when only a part of the identification information overlaps the area corresponding to the knurling processing area), thereby reducing the possibility of problems such as misalignment when winding the functional film or disappearance of the printing.

[0015] In the present invention, preferably, in the second step, after forming the knurled portion on the functional film, the identification information is printed on the knurled portion by an inkjet method, or after forming the knurled portion on the functional film, the identification information is printed so that at least a portion of the identification information does not overlap the portion corresponding to the knurled portion.

[0016] According to the above-mentioned preferred method, there is no risk of the identification information being lost due to the knurling process, compared to the case where the identification information is printed before the knurling process is formed (i.e., the identification information is printed on the area where the knurling process is to be formed), and the defect information and the identification information can be linked more appropriately.

[0017] In the present invention, preferably, in the second step, the identification information is printed by an inkjet method using a transparent ink.

[0018] In the second step of the present invention, it is also possible to use normal colored ink. However, according to the results of the study by the present inventors, it is easier to read the identification information by printing it using transparent ink, in distinction from the unevenness of the knurled part. The transparent ink is an ink that emits fluorescence when irradiated with light, and an example of the transparent ink is UV ink that emits fluorescence when irradiated with ultraviolet light. Therefore, according to the above-described preferred method, the defect information and the identification information can be linked more appropriately.

[0019] In the present invention, an example of the functional film is a protective film.

[0020] In order to solve the above problems, the present invention provides a method for producing a liquid crystal display comprising the steps of: The first system is The present invention is provided with an inspection device that inspects a long functional film to be laminated to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquires defect information of the functional film, a printing device that prints identification information at predetermined intervals in the longitudinal direction of the functional film on the widthwise end of the functional film, and a calculation storage device that stores the defect information of the functional film and the identification information in association with each other. picture , a knurled portion is formed at a width direction end of the functional film, and the printing device prints the identification information at a portion of the functional film corresponding to the knurled portion by an inkjet method. A functional film inspection system characterized by of offer vinegar do. In addition, the present invention provides a second system for inspecting a functional film, comprising an inspection device that inspects a long functional film to be laminated to a long polarizer or a long optical laminate containing a polarizer to produce a long polarizing film, and obtains defect information of the functional film, a printing device that prints identification information on an end portion of the functional film in the width direction at predetermined intervals in the longitudinal direction of the functional film, and a calculation and storage device that links and stores the defect information of the functional film and the identification information, wherein a knurling process portion is formed on the end portion of the functional film in the width direction, and the printing device prints the identification information so that at least a portion of the identification information does not overlap with a portion of the functional film corresponding to the knurling process portion.

[0021] Furthermore, in order to solve the above problems, the present invention provides As the first roll of raw material, A raw roll of a long functional film wound into a roll shape for producing a long polarizing film by bonding it to a long polarizer or a long optical laminate containing a polarizer, the raw roll having identification information printed thereon at predetermined intervals in the longitudinal direction of the functional film. Cage , A knurled portion is formed at a width direction end of the functional film, and the identification information is printed by an inkjet method at a portion of the functional film corresponding to the knurled portion. A roll of functional film of offer vinegar do. The present invention also provides a second original roll of functional film, which is a roll of a long functional film wound into a roll for producing a long polarizing film by bonding it to a long polarizer or a long optical laminate containing a polarizer, characterized in that identification information is printed on the functional film at predetermined intervals in the longitudinal direction, a knurling portion is formed at the widthwise end portion of the functional film, and the identification information is printed so that at least a portion of the identification information does not overlap with the portion of the functional film corresponding to the knurling portion.

[0023] The second aspect of the present inventionIn the raw roll, the knurled portions are formed intermittently at intervals in the longitudinal direction of the functional film, and the identification information is printed within the intervals. but preferable. The knurled areas of the functional film and the printed identification information are not necessary for the final polarizing film product, so they are cut, removed, and discarded at some point during the process of manufacturing the final polarizing film product. the above of In the preferred raw roll, the identification information is printed within the spaces between the knurled sections formed intermittently in the longitudinal direction of the functional film, so that by cutting the knurled sections in the longitudinal direction, the identification information can be simultaneously cut off. Therefore, there is no need to cut the widthwise ends of the functional film excessively, and it is possible to increase the yield of the functional film.

[0024] The above good In the preferred raw material roll, it is even more preferable that the knurled portion is formed intermittently in part of the functional film in the width direction. According to the more preferred raw roll described above, the knurling processing portion is intermittently formed in a part of the width direction of the functional film. In other words, the remaining part of the knurling processing portion in the width direction (width direction of the functional film) is continuously formed in the longitudinal direction of the functional film. Therefore, it is possible to increase the yield of the functional film while fully maintaining the function of the knurling processing portion to prevent the occurrence of winding misalignment when the functional film is wound up. Effect of the Invention

[0025] According to the present invention, defect information of functional films can be appropriately managed. [Brief description of the drawings]

[0026] [Figure 1] 1 is a flow diagram showing schematic steps of a functional film inspection method and a polarizing film inspection method according to an embodiment of the present invention. [Diagram 2]2 is a perspective view showing a schematic configuration of an inspection system for performing a first step S2 to a third step S4 shown in FIG. [Diagram 3] 1. FIG. 4 is a perspective view showing a schematic configuration of an inspection system for performing a fourth step S6 to a sixth step S8 shown in FIG. [Figure 4] FIG. 2 is a perspective view showing a schematic configuration of an inspection system for performing a seventh step S9 shown in FIG. [Diagram 5] FIG. 5 is a side view (as viewed in the width direction of polarizing film F2) that typically illustrates an example of the schematic configuration of a first reading device 9 and a second reading device 10 illustrated in FIG. 4. [Figure 6] 1. FIG. 2 is a perspective view showing a schematic configuration of an inspection system for performing a reading step S10, a second fourth step S11, and a sixth step S12 (the fourth step and the sixth step after the seventh step S9) shown in FIG. [Figure 7] 1A to 1C are diagrams showing examples of first identification information M and second identification information N printed by a functional film inspection method and a polarizing film inspection method according to an embodiment of the present invention. [Figure 8] An example of the result of reading the first identification information M of the polarizing film F2 shown in FIG. 7 by the first reading device 9 is shown. [Figure 9] An example of the result of reading the second identification information N of the polarizing film F2 shown in FIG. 7 by the second reading device 10 is shown. [Figure 10] 1. FIG. 4 is a diagram illustrating a printing example of first identification information M according to a modified example of the second step S3 shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, a functional film inspection method and a functional film inspection system according to one embodiment of the present invention will be described with reference to the attached drawings as appropriate. In this embodiment, an example will be given in which the functional film is a protective film that is bonded to a polarizer. Then, an embodiment including an inspection method and inspection system for not only a protective film but also a polarizing film manufactured by bonding a protective film to a polarizer will be described (hereinafter, the inspection method for the protective film and the polarizing film will be simply referred to as the "inspection method", and the inspection system for the protective film and the polarizing film will be simply referred to as the "inspection system"). First, a specific example of a polarizing film will be described.

[0028] <Polarizing film> The polarizing film is produced by a production method including: (A) a step of drying a polyvinyl alcohol-based film that has been subjected to dyeing treatment, crosslinking treatment, and stretching treatment to produce a polarizer; (B) a step of laminating a protective film to one or both sides of the polarizer; and (C) a step of performing a heat treatment after lamination.

[0029] The dyeing, crosslinking and stretching treatments of the polyvinyl alcohol film do not necessarily have to be performed separately, and may be performed simultaneously, and the order of each treatment may be arbitrary. In addition, a polyvinyl alcohol film that has been subjected to a swelling treatment may be used as the polyvinyl alcohol film. In general, the polyvinyl alcohol film is immersed in a solution containing iodine or a dichroic dye, and dyed by adsorbing iodine or a dichroic dye, and then washed, and uniaxially stretched at a stretching ratio of 3 to 7 times in a solution containing boric acid, borax, etc., and then dried. It is particularly preferable to stretch the film in a solution containing iodine or a dichroic dye, further stretch the film in a solution containing boric acid, borax, etc. (two-stage stretching), and then dry the film, since the orientation of iodine is increased and the polarization property is improved.

[0030] Examples of the polyvinyl alcohol polymer constituting the polyvinyl alcohol film include those obtained by polymerizing vinyl acetate and then saponifying it, and those obtained by copolymerizing vinyl acetate with a small amount of a copolymerizable monomer such as an unsaturated carboxylic acid, an unsaturated sulfonic acid, or a cationic monomer. The average polymerization degree of the polyvinyl alcohol polymer is not particularly limited and any one can be used, but is preferably 1000 or more, more preferably 2000 to 5000. The saponification degree of the polyvinyl alcohol polymer is preferably 85 mol% or more, more preferably 98 to 100 mol%.

[0031] The thickness of the produced polarizer is generally 5 to 80 μm, but is not limited thereto. In addition, the method for adjusting the thickness of the polarizer is also not particularly limited, and a typical method such as a tenter, roll stretching, or rolling can be used.

[0032] The bonding between the polarizer and the protective film is not particularly limited, and can be performed, for example, via an adhesive made of a vinyl alcohol-based polymer, or an adhesive made of at least a water-soluble crosslinking agent for a vinyl alcohol-based polymer such as boric acid, borax, glutaraldehyde, melamine, oxalic acid, etc. The adhesive layer for bonding the polarizer and the protective film is formed as a coated and dried layer of an aqueous solution, and when preparing the aqueous solution, other additives and catalysts such as acids can be added as necessary.

[0033] A suitable transparent film can be used as the protective film to be attached to one or both sides of the polarizer. Among them, a film made of a polymer having excellent transparency, mechanical strength, thermal stability, moisture shielding property, etc. is preferably used. Examples of the polymer include acetate-based resins such as triacetyl cellulose, polycarbonate-based resins, polyester-based resins such as polyarylate and polyethylene terephthalate, polyimide-based resins, polysulfone-based resins, polyethersulfone-based resins, polystyrene-based resins, polyolefin-based resins such as polyethylene and polypropylene, polyvinyl alcohol-based resins, polyvinyl chloride-based resins, polynorbornene-based resins, (meth)acrylic resins, polymethyl methacrylate-based resins, liquid crystal polymers, etc. The film may be manufactured by any of a casting method, a calendar method, and an extrusion method.

[0034] Also, the polymer film described in JP 2001-343529 A (WO01 / 37007) can be mentioned, for example, a resin composition containing (A) a thermoplastic resin having a substituted and / or unsubstituted imide group in the side chain, and (B) a thermoplastic resin having a substituted and / or unsubstituted phenyl and nitrile group in the side chain. A specific example is a film of a resin composition containing an alternating copolymer of isobutylene and N-methylmaleimide and an acrylonitrile-styrene copolymer. As the film, a film made of a mixed extrusion product of the resin composition can be used. These films have a small phase difference and a small photoelastic coefficient, so that they can eliminate problems such as unevenness caused by distortion of the polarizing film, and also have a small moisture permeability, so that they have excellent moisture durability.

[0035] In addition, it is preferable that the protective film is as colorless as possible. Therefore, a protective film having a retardation value in the film thickness direction expressed by Rth=[(nx+ny) / 2-nz]·d (where nx and ny are the main refractive indexes in the film plane, nz is the refractive index in the film thickness direction, and d is the film thickness) of -90 nm to +75 nm is preferably used. By using a film having a retardation value (Rth) in the thickness direction of -90 nm to +75 nm, coloring (optical coloring) of the polarizing film caused by the protective film can be almost eliminated. The retardation value (Rth) in the thickness direction is more preferably -80 nm to +60 nm, and particularly preferably -70 nm to +45 nm.

[0036] As the protective film, a (meth)acrylic resin is preferable in terms of polarization characteristics, durability, etc. Also, an acetate resin such as triacetyl cellulose is preferable, and in particular, a triacetyl cellulose film whose surface is saponified with an alkali or the like is preferable. When the protective films are attached to both sides of the polarizer, the front and back protective films may be made of different polymers.

[0037] The thickness of the protective film is optional, but is generally set to 500 μm or less, preferably 1 to 300 μm, and particularly preferably 5 to 200 μm, for the purpose of making the polarizing film thinner.

[0038] The protective film may be subjected to a hard coat treatment, an anti-reflection treatment, or a treatment for preventing sticking, diffusing or anti-glare, etc., so long as the object of the present invention is not impaired. The hard coat treatment is performed for the purpose of preventing the surface of the polarizing film from being scratched, and can be formed by, for example, adding a cured film excellent in hardness, slipperiness, etc., made of an appropriate ultraviolet-curable resin such as a silicone-based resin to the surface of the protective film.

[0039] On the other hand, the anti-reflection treatment is performed for the purpose of preventing reflection of external light on the surface of the polarizing film, and can be achieved by forming a conventional anti-reflection film, etc. The sticking prevention is performed for the purpose of preventing adhesion with adjacent layers, and the anti-glare treatment is performed for the purpose of preventing reflection of external light on the surface of the polarizing film from impairing visibility of light transmitted through the polarizing film, and can be formed by imparting a fine uneven structure to the surface of the protective film by an appropriate method such as a roughening method using a sandblasting method or an embossing method, or a method of blending transparent fine particles.

[0040] The transparent fine particles include, for example, silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide, etc., each having an average particle size of 0.5 to 20 μm. Inorganic fine particles having electrical conductivity may be used, and organic fine particles made of crosslinked or uncrosslinked polymer particles, etc. may also be used. The amount of the transparent fine particles used is generally 2 to 70 parts by mass, particularly 5 to 50 parts by mass, per 100 parts by mass of the transparent resin.

[0041] Furthermore, the anti-glare layer containing transparent fine particles can be provided as the transparent protective layer itself, or as a coating layer on the surface of the transparent protective layer. The anti-glare layer may also serve as a diffusion layer (such as a viewing angle compensation function) for diffusing light transmitted through the polarizing film to expand the viewing angle. The above-mentioned anti-reflection layer, anti-sticking layer, diffusion layer, anti-glare layer, etc. can also be provided as an optical layer consisting of a sheet on which these layers are provided, separate from the transparent protective layer.

[0042] <Inspection method according to this embodiment> The inspection method according to this embodiment will be described below. Fig. 1 is a flow diagram showing the outline of the steps of the inspection method according to the present embodiment. As shown in Fig. 1, the inspection method according to the present embodiment includes steps S1 to S4 carried out in the manufacturing process of the protective film (steps included in the inspection method of the functional film (protective film) according to the present invention) and steps S5 to S12 carried out in the manufacturing process of the polarizing film. Each step will be described in order below. In this embodiment, the "defect information" in the functional film (protective film) inspection method and inspection system of the present invention is referred to as "first defect information," and the "identification information" is referred to as "first identification information." Also, in the functional film (protective film) inspection system of the present invention, the "inspection device" is referred to as the "first inspection device," the "printing device" is referred to as the "first printing device," and the "calculation and storage device" is referred to as the "first calculation and storage device."

[0043] [Processes carried out in the manufacturing process of functional films (protective films)] In the manufacturing process of the functional film (protective film), a first step S2 to a third step S4 are performed. In this embodiment, a knurling process S1 is performed before the first step S2.

[0044] (Knurling process S1) In the knurling process S1, a knurling process is performed on the width direction end of the protective film F1 to form a knurled portion. The specific content of the knurling process is publicly known, for example, as described in Patent Document 2, and therefore a detailed description thereof will be omitted here.

[0045] (1st process S2) FIG. 2 is a perspective view that shows a schematic configuration of an inspection system for performing the first step S2 to the third step S4. As shown in Figure 2, in the first step S2, the first inspection device 1 provided in the inspection system 100 inspects the protective film F1 being transported in a roll-to-roll manner by a transport roll R (transported in the direction indicated by the thick arrow in Figure 2) and obtains first defect information, which is defect information of the protective film F1. The first inspection device 1 includes an imaging means 1a arranged opposite to the surface of the protective film F1, and an image processing means 1b electrically connected to the imaging means 1a and performing appropriate image processing on the captured image of the surface of the protective film F1 acquired by the imaging means 1a. As the imaging means 1a, a line sensor in which imaging elements are linearly arranged along the width direction of the protective film F1, or an area sensor in which imaging elements are arranged in a matrix can be used. The field of view of the imaging means 1a is set to be equal to or greater than the effective width (width used for the product) of the protective film F1. The image processing means 1b extracts pixel areas corresponding to defects present in the protective film F1 by performing known image processing such as binarization on the captured image. Then, the image processing means 1b identifies the position of the defect (the coordinates of the pixel area corresponding to the defect) in the captured image, and acquires information including at least the position of the identified defect as first defect information. The acquired first defect information is input to a first arithmetic and memory device 4 provided in the inspection system 100.

[0046] (2nd process S3) In the second step S3, the first printer 2 included in the inspection system 100 prints first identification information M at a predetermined interval (e.g., equal intervals of 1 m) in the longitudinal direction of the protective film F1 on the widthwise end portion (preferably, the knurling processing portion) of the protective film F1. Fig. 2 shows an example in which the first identification information M1 to M3 are printed in order from the leading end side (the downstream side in the transport direction) of the protective film F1. The first identification information M is information including at least information for identifying the longitudinal position of the protective film F1. The first identification information M is, for example, a two-dimensional code or a barcode that represents a numerical value that increases or decreases from the leading end of the protective film F1 (the numerical value identifies the longitudinal position of the protective film F1). In addition to information for identifying the longitudinal position of the protective film F1, the first identification information M can include various additional information such as the date and time of printing, the manufacturing number of the protective film F1, and the type of process in which the information was printed.

[0047] In this embodiment, the printing of the first identification information M by the first printer 2 is controlled by the first arithmetic and memory device 4. Specifically, a length measuring device 3 using a rotary encoder or the like measures the amount of movement of the protective film F1 in the transport direction and inputs the amount of movement to the first arithmetic and memory device 4. Based on the amount of movement input from the length measuring device 3, the first arithmetic and memory device 4 transmits a control signal to the first printer 2 at predetermined intervals, causing the first printer 2 to print the first identification information M at predetermined intervals. In this embodiment, an example has been described in which the first arithmetic and memory device 4 also has the function of controlling the first printing device 2, but the present invention is not limited to this, and it is also possible to adopt a configuration in which a control device separate from the first arithmetic and memory device 4 controls the first printing device 2.

[0048] The first printing device 2 of this embodiment prints the first identification information M by an inkjet system. As a preferred embodiment, the first printing device 2 of this embodiment prints the first identification information M by an inkjet system using transparent ink. Specifically, in this embodiment, the first identification information M is printed by an inkjet system using UV ink, which emits fluorescence when irradiated with ultraviolet light, as the transparent ink. As the first printing device 2, for example, an inkjet printer "VJ1000 series" manufactured by Videojet Corporation or an inkjet printer "Gravis UX series" manufactured by Hitachi Industrial Equipment Co., Ltd. can be used.

[0049] (3rd process S4) In the third step S4, the first arithmetic and memory device 4 associates and stores the first defect information of the protective film F1 with the first identification information M. Specifically, the process is as follows. For example, suppose that the first inspection device 1 detects the defect D1 shown in FIG. 2, identifies the position of the defect D1 in the captured image (the coordinates of the pixel area corresponding to the defect D1), and inputs this as the first defect information to the first calculation storage device 4. Since the movement amount of the protective film F1 in the transport direction is input from the length measuring device 3 to the first calculation storage device 4, the first calculation storage device 4 can grasp how much the protective film F1 has moved in the transport direction between the time when the defect D1 is detected (the time when the coordinates of the pixel area corresponding to the defect D1 in the captured image are identified) and the time when the first printing device 2 prints the first identification information M. Based on the movement amount of the protective film F1 between these two times and the coordinates of the pixel area corresponding to the defect D1 in the captured image, the first calculation storage device 4 can calculate the distance X1 (the distance along the longitudinal direction of the protective film F1) from the predetermined first identification information M (the first identification information M3 in the example shown in FIG. 2) to the defect D1. Furthermore, the first arithmetic and memory device 4 can calculate a distance Y1 from the edge in the width direction of the protective film F1 to the defect D1 (the distance along the width direction of the protective film F1) based on the coordinates of the pixel area corresponding to the defect D1 in the captured image. The first arithmetic and memory device 4 stores at least the first identification information M (M3) and the coordinates (X1, Y1) of the defect D1 based on the first identification information M (M3) in association with each other.

[0050] [Processes carried out in the manufacturing process of polarizing film] The protective film F1 produced in the above-mentioned manufacturing process (the protective film with the first identification information M printed on the knurled portion by an inkjet method) is wound into a roll to form a raw roll of protective film F1. The raw roll of protective film F1 is transported to a manufacturing process for polarizing film. In the manufacturing process for polarizing film, the raw roll of protective film F1 that has been transported is used. 1, the manufacturing process of the polarizing film of this embodiment includes step No. 1 and step No. 2. In the manufacturing process of the polarizing film of this embodiment, after the fourth step S6 to the seventh step S9 are performed in step No. 1, the fourth step S11 and the sixth step S12 are performed again in step No. 2. In addition, in the manufacturing process of the polarizing film of this embodiment, the bonding step S5 is performed in step No. 1, and the reading step S10 is performed in step No. 2.

[0051] (Laminating process S5) In step No. 1, a raw roll of the protective film F1 is unwound, and a raw roll of the polarizer is unwound. Then, in the lamination step S5, the protective film F1 is laminated to one or both sides of the polarizer via an adhesive or the like as described above to obtain a polarizing film F2 in which the protective film F1 and the polarizer are laminated.

[0052] (4th step S6) FIG. 3 is a perspective view that shows a schematic configuration of an inspection system for performing the fourth step S6 to the sixth step S8. As shown in Figure 3, in the fourth step S6, the second inspection device 5 provided in the inspection system 100 inspects the polarizing film F2 being transported in a roll-to-roll manner by the transport roll R (transported in the direction indicated by the thick arrow in Figure 3) to obtain second defect information, which is defect information about the polarizing film F2. The second inspection device 5, like the first inspection device 1 shown in Fig. 2, is equipped with an imaging means 5a and an image processing means 5b, and has the same functions as the first inspection device 1, so a detailed description will be omitted here. The second inspection device 5 identifies the position of a defect in the captured image (the coordinates of a pixel area corresponding to the defect) and acquires information including at least the position of the identified defect as second defect information. The acquired second defect information is input to a second arithmetic and memory device 8 provided in the inspection system 100.

[0053] (5th step S7) In a fifth step S7, a second printer 6 included in the inspection system 100 prints second identification information N at predetermined intervals (e.g., equal intervals of 1 m) in the longitudinal direction of the polarizing film F2 on the widthwise end of the polarizing film F2 (preferably, on a portion of the polarizing film F2 located widthwise inward of the knurled portion of the protective film F1). FIG. 3 illustrates an example in which the second identification information N1 to N3 are printed in order from the leading end side (downstream side in the conveying direction) of the polarizing film F2. Note that, in reality, the first identification information M is printed on the protective film F1 constituting the polarizing film F2, but for convenience, the first identification information M is not illustrated in FIG. 3. The second identification information N differs from the first identification information M, which includes information identifying at least the longitudinal position of the polarizing film F2, in that it includes information identifying at least the longitudinal position of the protective film F1; in other respects, it is similar to the first identification information M, so a detailed description of it will be omitted here.

[0054] In this embodiment, the second identification information N printed on the polarizing film F2 is printed on the same protective film F1 on which the first identification information M is printed, but the present invention is not limited to this. For example, when forming a polarizing film F2 by bonding protective films F1 to both sides of a polarizer, it is possible to print a first identification information M on one of the protective films F1 and print a second identification information N on the other protective film (which may also serve as a retardation film) on which the first identification information M is not printed. Furthermore, for example, when protective films F1 are bonded to both sides of a polarizer and a retardation film is further bonded to one of the protective films F1 to form a polarizing film F2 with retardation function, it is also possible to print the first identification information M on the other protective film F1 and print the second identification information N on the retardation film.

[0055] Just as the printing of the first identification information M by the first printer 2 is controlled by the first calculation storage device 4, the printing of the second identification information N by the second printer 6 is controlled by the second calculation storage device 8. The specific control contents are similar to the control of the printing of the first identification information M by the first printer 2, so a detailed description will be omitted here.

[0056] The second printing device 6 of this embodiment prints the second identification information N by laser engraving, unlike the first printing device 2. As the second printing device 6, various known printing devices having a function of printing by laser engraving using, for example, a CO2 laser can be applied, and therefore detailed description thereof will be omitted here.

[0057] (6th step S8) In a sixth step S8, the second arithmetic and memory device 8 associates the second defect information of the polarizing film F2 with the second identification information N and stores them. Specifically, since the procedure is the same as that in the case where the first arithmetic and memory device 4 associates and stores the first defect information of the protective film F1 with the first identification information M, a detailed description will be omitted. However, the second arithmetic and memory device 8 associates and stores at least the second identification information N (the second identification information N3 in the example shown in FIG. 3) with the coordinates (X2, Y2) of the defect D2 based on the second identification information N (N3) using the amount of movement in the conveying direction of the polarizing film F2 input from the length measuring device 7 having the same configuration as the length measuring device 3.

[0058] (7th step S9) FIG. 4 is a perspective view that illustrates a schematic configuration of an inspection system for performing the seventh step S9. In the seventh step S9, the second arithmetic and memory device 8 associates the first defect information of the protective film F1 with the second identification information of the polarizing film F2 and stores them. Specifically, a first reader 9 for reading the first identification information M (FIG. 4 shows the first identification information M1 to M3) and a second reader 10 for reading the second identification information N (FIG. 4 shows the second identification information N1 to N3) are disposed, and the first identification information M read by the first reader 9 and the second identification information N read by the second reader 10 are input to the second arithmetic and memory device 8. Here, the association between the first defect information of the protective film F1 and the first identification information M stored in the first arithmetic and memory device 4 (the relationship between the first identification information M and the coordinates of the defect based on the first identification information M) is input and stored in the second arithmetic and memory device 8 in advance. The link between the first defect information and the first identification information M may be input by electrically connecting the first calculation storage device 4 and the second calculation storage device 8 and transmitting the link from the first calculation storage device 4 to the second calculation storage device 8, or by downloading the link from the first calculation storage device 4 and manually inputting the link to the second calculation storage device 8. In addition, the second calculation storage device 8 receives an input of the movement amount of the polarizing film F2 in the transport direction from a length measuring device 11 having a similar configuration to the length measuring device 3.

[0059] The second arithmetic and memory device 8 can grasp how much the polarizing film F2 has moved in the transport direction between the time when the first reading device 9 reads the first identification information M (the time when the first identification information M is input to the second arithmetic and memory device 8) and the time when the second reading device 10 reads the second identification information N (the time when the second identification information N is input to the second arithmetic and memory device 8) based on the amount of movement of the polarizing film F2 in the transport direction input from the length measuring device 11. Based on the amount of movement of the polarizing film F2 between these two times, the second arithmetic and memory device 8 can calculate the positional deviation between the first identification information M and the second identification information N along the longitudinal direction of the polarizing film F2 (the positional deviation dX between the first identification information M3 and the second identification information N3 in the example shown in FIG. 4). Therefore, the second arithmetic and memory device 8 can store the first defect information of the protective film F1 and the second identification information N of the polarizing film F2 in association with each other based on the association between the first defect information of the protective film F1 and the first identification information M stored in advance and the calculated positional deviation between the first identification information M and the second identification information N. In other words, the second identification information N can be stored in association with the coordinates of the defect based on the second identification information N. In this way, by performing the seventh step S9, the first defect information and the second defect information can be managed in a unified manner based on the second identification information N of the polarizing film F2. After the seventh step S9, the polarizing film F2 is wound into a roll and transported to the No. 2 step.

[0060] 5 is a side view (a side view seen from the width direction of the polarizing film F2) showing a schematic configuration example of the first reading device 9 and the second reading device 10. Fig. 5(a) shows a schematic configuration example of the first reading device 9, and Fig. 5(b) shows a schematic configuration example of the second reading device 10. As shown in FIG. 5(a), the first reading device 9 includes a UV illuminator 91 that emits ultraviolet light, and an imaging means (area sensor) 92. By irradiating the surface of the polarizing film F2 with ultraviolet light emitted from the UV illuminator 91, the first identification information M printed with transparent ink (UV ink) emits fluorescence. As a result, in an image captured by the imaging means 92 arranged on the same side as the UV illuminator 91 (the upper side in the example shown in FIG. 5(a)) with respect to the surface of the polarizing film F2, the pixel area corresponding to the first identification information M becomes bright (the pixel area corresponding to the second identification information N becomes dark like the background), and the first identification information M can be read in distinction from the second identification information N. In addition, the first identification information M can be read in distinction from the unevenness of the knurled portion. For example, a device that emits ultraviolet light having a wavelength of about 200 to 400 nm, preferably about 365 nm, can be used as the UV illumination 91. Furthermore, for example, an area sensor with a high-speed shutter having a shutter speed (exposure time) of about 30 to 150 μsec can be used as the imaging means 92.

[0061] As shown in FIG. 5(b), the second reading device 10 is provided with an illumination 101 that is disposed on one side (the lower side in the example shown in FIG. 5(b)) of the surface of the polarizing film F2 and emits a parallel light beam, and an imaging means (area sensor) 102 that is disposed on the other side (the upper side in the example shown in FIG. 5(b)) of the surface of the polarizing film F2 and receives the light that has passed through the polarizing film F2. The parallel light beam emitted from the illumination 101 and irradiated onto the surface of the polarizing film F2 is scattered by the second identification information N printed by laser engraving. As a result, in the captured image acquired by the imaging means 102, the pixel area corresponding to the second identification information N becomes dark (the pixel area corresponding to the first identification information M becomes bright like the background), and the second identification information N can be read in distinction from the first identification information M. In addition, the second identification information N can be read in distinction from the unevenness of the knurled portion.

[0062] Although detailed description will be omitted, when the first identification information M is printed using normal colored ink, by using a reading device in which the illumination 101 shown in Fig. 5(b) is replaced with an illumination that irradiates diffused light as a reading device for reading the first identification information M, the pixel area corresponding to the first identification information M in the captured image acquired by the imaging means 102 becomes dark (the pixel area corresponding to the second identification information N becomes bright like the background), and the first identification information M can be read in distinction from the second identification information N. Also, the first identification information M can be read in distinction from the unevenness of the knurled portion.

[0063] (Reading step S10) In step No. 2, the polarizing film F2 wound in a roll is unwound. Then, the reading step S10 is first performed. Fig. 6 is a perspective view showing a schematic configuration of an inspection system for performing the reading step S10, the second fourth step S11 and the sixth step S12 (the fourth step and the sixth step after the seventh step S9). Note that, in reality, the first identification information M is printed on the protective film F1 constituting the polarizing film F2, but for convenience, the first identification information M is not shown in Fig. 6. 6, in the reading step S10, the second identification information N is read by a second reading device 12 having a configuration similar to that of the second reading device 10 (see FIGS. 4 and 5(b)) included in the inspection system 100. The read second identification information N is input to a second storage device 8.

[0064] (4th process (2nd time) S11) In the second fourth step S11, a second inspection device 13 (imaging means 13a and image processing means 13b) having a configuration similar to that of the second inspection device 5 included in the inspection system 100 inspects the polarizing film F2 transported by the transport roll R in a roll-to-roll manner (transported in the direction indicated by the thick arrow in FIG. 6) to obtain second defect information that is defect information on the polarizing film F2. The obtained second defect information is input to the second arithmetic and memory device 8.

[0065] (6th process (2nd time) S12) In the second sixth step S12, the second arithmetic and memory device 8 associates and stores the second defect information of the polarizing film F2 acquired by the second inspection device 13 with the second identification information N read by the second reading device 12. Specifically, the second arithmetic and memory device 8 uses the amount of movement of the polarizing film F2 in the transport direction input from a length measuring device 14 having a similar configuration to the length measuring device 3 to determine how much the polarizing film F2 has moved in the transport direction between the time when the second identification information N is read by the second reading device 12 and the time when the defect is detected by the second inspection device 13 (the time when the coordinates of the pixel area corresponding to the defect in the captured image are identified), and stores at least the second identification information N and the coordinates of the defect based on the second identification information N in association with each other.

[0066] In this embodiment, an example has been described in which two inspections (inspection by the second inspection device 5 and inspection by the second inspection device 13) are performed in the manufacturing process of the polarizing film F2. However, if three or more inspections are performed, the reading step S10, the fourth step S11 and the sixth step S12 can be repeatedly performed in the second and subsequent inspections.

[0067] According to the inspection method of the present embodiment described above, since the first identification information M is printed by the inkjet method, as the inventors have found, the first identification information M can be read separately from the unevenness of the knurled portion. Furthermore, since the first identification information M is printed by the inkjet method and the second identification information N is printed by laser engraving, according to the inventors' findings, even if the first identification information M and the second identification information N overlap, they can be read separately. That is, the defect information and the identification information can be appropriately linked (the first defect information and the first identification information M (and thus the second identification information N) can be linked, and the second defect information and the second identification information N can be linked). Furthermore, for example, by reading the second identification information N and linking the second defect information stored in the sixth steps S8 and S12 with the second identification information N, and also by linking the first defect information stored in the seventh step S9 with the second identification information N, it is possible to punch out the product while avoiding the positions of defects that occurred in the protective film F1 state and the positions of defects that occurred in the polarizing film F2 state.

[0068] However, this is not limited to the embodiment in which the first identification information M is printed by the inkjet method and the second identification information N is printed by laser engraving. The first identification information M and the second identification information N can be read separately even if one of the first identification information M and the second identification information N is printed by the inkjet method and the other is printed by laser engraving, or if one of the first identification information M and the second identification information N is printed by the inkjet method using a transparent ink and the other is printed by the inkjet method using a colored ink.

[0069] In addition, as a preferred embodiment, the inspection method according to the present embodiment may also include an eighth step (not shown in FIG. 1) of marking the position of a defect in the polarizing film F2 based on the linkage between the first identification information M of the protective film F1 (and thus the second identification information N of the polarizing film F2) and the first defect information, and the linkage between the second identification information N of the polarizing film F2 and the second defect information. Specifically, it is also possible to read the second identification information N and apply marking by an inkjet method or marking using a marker similar to that described in Patent Document 1 to the position of the defect included in the first defect information and the second defect information. By including the eighth step of applying marking, marking is applied to the position of the defect, so that the position of the defect can be identified even by visual inspection.

[0070] FIG. 7 is a diagram showing an example of printing of the first identification information M and the second identification information N by the inspection method according to the present embodiment. The example shown in FIG. 7 is a polarizing film F2 formed by using a triacetyl cellulose (TAC) protective film and an acrylic protective film as the protective film F1 and laminating these protective films F1 on both sides of a polarizer. In the example shown in FIG. 7, the first identification information M is printed on the acrylic protective film by an inkjet method using transparent ink (UV ink), and then the acrylic protective film and the TAC protective film are laminated on both sides of a polarizer, respectively, and then the second identification information N is printed on the TAC protective film side by laser engraving. The circular irregularities shown in FIG. 7 are knurled parts formed on the width direction end of the acrylic protective film, and the diamond-shaped irregularities are knurled parts formed on the width direction end of the TAC protective film. The captured image shown in Figure 7 is an image obtained when the polarizing film F2 is illuminated using both the UV illumination 91 provided in the first reading device 9 and the illumination 101 provided in the second reading device 10 simultaneously.

[0071] Fig. 8 shows an example of the results of reading the first identification information M of the polarizing film F2 shown in Fig. 7 by the first reading device 9. As shown in Fig. 8, in the captured image acquired by the first reading device 9, the pixel area corresponding to the first identification information M becomes bright (the pixel area corresponding to the second identification information N becomes dark like the background), and it can be seen that the first identification information M can be read in distinction from the second identification information N. It can also be seen that the first identification information M can be read in distinction from the unevenness of the knurled portion.

[0072] Fig. 9 shows an example of the results of reading the second identification information N of the polarizing film F2 shown in Fig. 7 by the second reading device 10. As shown in Fig. 9, in the captured image acquired by the second reading device 10, the pixel area corresponding to the second identification information N becomes dark (the pixel area corresponding to the first identification information M becomes bright like the background), and it is clear that the second identification information N can be read in distinction from the first identification information M. It is also clear that the second identification information N can be read in distinction from the unevenness of the knurled portion.

[0073] In this embodiment, an example has been described in which the first identification information M is printed on the protective film F1 in the second step S3 after the knurling process step S1 is performed (after the knurling process portion is formed on the protective film F1), but the present invention is not limited to this. It is also possible to print the first identification information M in the area where the knurling process portion is to be formed before the knurling process portion is formed (i.e., the knurling process portion is formed after the first identification information M is printed).

[0074] In addition, in the present embodiment, the case where the polarizing film F2 is inspected multiple times has been described as an example, but the present invention is not limited to this, and the polarizing film F2 can be inspected only once. In this case, the reading step S10, the fourth step (second time) S11, and the sixth step (second time) S12 shown in Fig. 1 are unnecessary. However, the reading step S10 is necessary when punching out a product while avoiding the positions of defects that occurred in the protective film F1 state and the positions of defects that occurred in the polarizing film F2 state, or when performing the eighth step of applying markings to the positions of defects in the polarizing film F2.

[0075] In addition, in the present embodiment, the case where the protective film F1 is inspected only once has been described as an example, but the present invention is not limited thereto, and it is possible to inspect the protective film F1 multiple times, as in the case of the inspection of the polarizing film F2. In this case, in the second and subsequent inspections, after the third step S4 shown in FIG. 1, it is necessary to repeatedly execute the reading step of reading the first identification information M, the step of acquiring the first defect information similar to the first step S2, and the step of linking and storing the first defect information and the first identification information M similar to the third step S4.

[0076] In the present embodiment, the seventh step S9 is performed to centrally manage the first defect information and the second defect information based on the second identification information N of the polarizing film F2. However, the present invention is not limited to this. It is also possible to manage the first defect information based on the first identification information M and manage the second defect information based on the second identification information N without performing the seventh step S9. Specifically, for example, it is also possible to punch out the product while avoiding the position of the defect that occurred in the state of the protective film F1 by reading the first identification information M and using the association between the first defect information and the first identification information M stored in the third step S4, and to punch out the product while avoiding the position of the defect that occurred in the state of the polarizing film F2 by reading the second identification information N and using the association between the second defect information and the second identification information N stored in the sixth step S8.

[0077] In the present embodiment, the example in which the first identification information M is printed on the knurled portion of the protective film F1 in the second step S3 has been described, but the present invention is not limited to this. It is also possible to adopt a modified example in which the first identification information M is printed so that at least a part of the first identification information M does not overlap the portion of the protective film F1 that corresponds to the knurled portion.

[0078] Fig. 10 is a diagram showing a schematic example of printing of first identification information M according to a modified example of the second step S3. Fig. 10(a) shows a protective film F1 on which the first identification information M is printed, and Fig. 10(b) shows an enlarged view of an area surrounded by a dashed line A in Fig. 10(a). The vertical direction in Fig. 10 corresponds to the longitudinal direction of the protective film F1, and the horizontal direction in Fig. 10 corresponds to the width direction of the protective film F1. In the example shown in Fig. 10, a knurling processing section K consisting of two rows of processed sections Ka and Kb is formed at each end in the width direction of the protective film F1. To form the two rows of processed sections Ka and Kb, for example, two laser light sources are arranged at each end in the width direction of the protective film F1, and while transporting the protective film F1 in the longitudinal direction, a laser light emitted from one laser light source is scanned in the width direction by a distance corresponding to the width of the processed section Ka to irradiate the protective film F1, and a laser light emitted from the other laser light source is scanned in the width direction by a distance corresponding to the width of the processed section Kb to irradiate the protective film F1.

[0079] In the example shown in Fig. 10, knurling processed portions K formed at the widthwise end portion (the end portion on the left side in Fig. 10) of the protective film F1 on the side where the first identification information M is printed are formed intermittently at intervals G in the longitudinal direction of the protective film F1. Specifically, the knurling processed portions K are formed intermittently at intervals G in a part of the width direction of the protective film F1 (in the example shown in Fig. 10, the processed portion Ka located on the outer side in the width direction of the protective film F1 out of the two rows of processed portions Ka, Kb). Then, in a modified example of the second process S3, the first identification information M is printed within this interval G. In addition, to form knurling processing portion K intermittently in a portion of the width direction of the protective film F1 (processing portion Ka), for example, the emission of laser light from the laser light source for forming the processing portion Ka may be stopped at a portion corresponding to the interval G.

[0080] According to the modified example of the second process S3 described above, at least a portion of the first identification information M does not overlap the area corresponding to the knurling processing portion K (in the example shown in Figure 10, the entire first identification information M does not overlap), which reduces the possibility of problems such as misalignment when winding the protective film F1 or disappearance of the printing when winding the protective film F1. 10, the first identification information M is printed within the intervals G of the knurled portions K intermittently formed in the longitudinal direction of the protective film F1, and therefore, by cutting the knurled portions K in the longitudinal direction, the first identification information M can be simultaneously cut. Therefore, there is no need to cut the widthwise ends of the protective film F1 excessively, and it is possible to increase the yield of the protective film F1. 10, the knurling process portion K is intermittently formed in a portion (processing portion Ka) of the protective film F1 in the width direction. In other words, the remaining portion (processing portion Kb) of the knurling process portion K in the width direction is continuously formed in the longitudinal direction of the protective film F1. Therefore, it is possible to increase the yield of the protective film F1 while fully maintaining the function of the knurling process portion K to prevent the occurrence of misalignment when the protective film F1 is wound up.

[0081] 10, and may be, for example, when the entire knurled portion K (i.e., both processed portions Ka and Kb) are formed intermittently at intervals in the longitudinal direction of the protective film F1, the first identification information M may be printed within the intervals. Also, when the knurled portion K is formed continuously (i.e., there is no interval G), the first identification information M may be printed on the inner or outer side of the knurled portion K in the width direction of the protective film F1 (including the case where a part of the first identification information M overlaps the knurled portion K).

[0082] In the present embodiment and the modified example of the second step S3, the functional film is a protective film to be bonded to a polarizer, but the present invention is not limited thereto. As long as the functional film is bonded to a polarizer or an optical laminate including a polarizer to produce a polarizing film, the present invention can be applied to various functional films. Examples of the functional film to be attached to the polarizer include the protective film (including the film that also functions as a retardation film) exemplified in this embodiment and a retardation film. An example of an optical laminate containing a polarizer is one in which a protective film is laminated on a polarizer. Examples of functional films to be attached to this optical laminate are retardation films, reflective polarizers, antireflection films, conductive films such as ITO films, and window films made of, for example, polyimide. [Explanation of symbols]

[0083] 1. First inspection device (inspection device) 2...1st printing device (printing device) 3, 7, 11, 14: Length measuring device 4...1st arithmetic storage device (arithmetic storage device) 5, 13...Second inspection device 6...Second printing device 8...Second arithmetic storage device 9. First reading device 10, 12: Second reading device 100···Inspection system F1···Functional film (protective film) F2...Polarizing Film M...First identification information N Second identification information

Claims

1. A first step of inspecting a long functional film to be bonded to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquiring defect information of the functional film; a second step of printing identification information on the widthwise end portions of the functional film at predetermined intervals in the longitudinal direction of the functional film; a third step of storing the defect information and the identification information of the functional film in association with each other, A knurled portion is formed at the width direction end of the functional film, In the second step, the identification information is printed by an inkjet method on a portion of the functional film corresponding to the knurled portion. A functional film inspection method comprising:

2. A first step of inspecting a long functional film to be laminated to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquiring defect information of the functional film; a second step of printing identification information on the widthwise end portions of the functional film at predetermined intervals in the longitudinal direction of the functional film; a third step of storing the defect information and the identification information of the functional film in association with each other, A knurled portion is formed at the width direction end of the functional film, In the second step, the identification information is printed on the functional film in a region corresponding to the knurled portion such that at least a portion of the identification information does not overlap the region. A functional film inspection method comprising:

3. In the second step, after forming the knurled portion on the functional film, the identification information is printed on the knurled portion by an inkjet method, or after forming the knurled portion on the functional film, the identification information is printed on a portion corresponding to the knurled portion such that at least a portion of the identification information does not overlap the portion.

3. The functional film inspection method according to claim 1 or 2.

4. In the second step, the identification information is printed by an inkjet method using a transparent ink.

4. The functional film inspection method according to claim 1, wherein the functional film is inspected by a measuring device.

5. The functional film is a protective film.

5. The functional film inspection method according to claim 1, wherein the functional film is inspected by a measuring device.

6. an inspection device that inspects a long functional film to be bonded to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquires defect information about the functional film; a printing device that prints identification information on the widthwise end of the functional film at predetermined intervals in the longitudinal direction of the functional film; a calculation and storage device that stores the defect information and the identification information of the functional film in association with each other, A knurled portion is formed at the width direction end of the functional film, The printing device prints the identification information on a portion of the functional film corresponding to the knurling processing portion by an inkjet method. A functional film inspection system comprising:

7. An inspection device for inspecting a long functional film to be laminated to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, and acquiring defect information of the functional film; a printing device that prints identification information on the widthwise end of the functional film at predetermined intervals in the longitudinal direction of the functional film; a calculation and storage device that stores the defect information and the identification information of the functional film in association with each other, A knurled portion is formed at the width direction end of the functional film, The printing device prints the identification information such that at least a portion of the identification information does not overlap a portion of the functional film that corresponds to the knurling processing portion. A functional film inspection system comprising:

8. A raw material roll in which a long functional film is wound into a roll shape to be laminated to a long polarizer or a long optical laminate including a polarizer to produce a long polarizing film, Identification information is printed at predetermined intervals in the longitudinal direction of the functional film, A knurled portion is formed at the width direction end of the functional film, The identification information is printed by an inkjet method on a portion of the functional film corresponding to the knurled portion. A raw roll of functional film.

9. A raw roll of a long functional film wound into a roll for producing a long polarizing film by bonding it to a long polarizer or a long optical laminate including a polarizer, Identification information is printed at predetermined intervals in the longitudinal direction of the functional film, A knurled portion is formed at the width direction end of the functional film, The identification information is printed so that at least a part of the identification information does not overlap with a portion of the functional film corresponding to the knurled portion. A raw roll of functional film.

10. The knurling processing portion is formed intermittently at intervals in the longitudinal direction of the functional film, The identification information is printed within the space.

10. The functional film roll according to claim 9.

11. The knurling process portion is intermittently formed in a part of the width direction of the functional film. The functional film roll according to claim 10 .

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