CN114846320A

CN114846320A - Method and system for inspecting long optical laminate

Info

Publication number: CN114846320A
Application number: CN202080085745.6A
Authority: CN
Inventors: 三笠康之; 松林恭平; 田壶宏和; 村上洋介; 神丸刚
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2019-12-10
Filing date: 2020-12-07
Publication date: 2022-08-02
Also published as: TW202129265A; TWI834897B; KR20220106744A; JPWO2021117670A1; WO2021117273A1; JP7522763B2; TW202129264A; WO2021117670A1

Abstract

Both the first identification information printed on the first long optical film and the second identification information printed on the long optical laminate can be read in the state of the long optical laminate. The method comprises the following steps: a first step of inspecting the first long optical film (F1) to obtain first defect information; a second step of printing first identification information (M) on the first long optical film; a third step of storing the first defect information in association with the first identification information; a fourth step of inspecting the long optical laminate (F2) on which the first long optical film is laminated to obtain second defect information; a fifth step of printing second identification information on the long optical laminate; a sixth step of storing the second defect information in association with the second identification information; either one of the first identification information and the second identification information is printed by an ink jet method and the other is printed by laser engraving, or either one is printed by an ink jet method using a clear ink and the other is printed by an ink jet method using a colored ink.

Description

Method and system for inspecting long optical laminate

Technical Field

The present invention relates to an inspection method and an inspection system for an elongated optical laminate (e.g., polarizing film) in which a first elongated optical film (e.g., protective film) and a second elongated optical film (e.g., polarizing plate) are laminated. The present invention particularly relates to an inspection method and an inspection system for a long optical laminate which can appropriately relate defect information and identification information by enabling both first identification information printed on a first long optical film and second identification information printed on a second long optical film or a long optical laminate to be read in a state of the long optical laminate.

Background

As a long optical laminate, for example, a polarizing film used in a liquid crystal display device is known. The steps from the long polarizing film to punching out the polarizing film having a size corresponding to the application are as follows, for example.

First, a long polarizing film conveyed in a roll-to-roll manner is inspected to detect defects in the polarizing film. When a defect is detected, the position of the defect is marked and the polarizing film is wound.

In a polarizing film (punched polarizing film) as a final product, various sizes are available according to the specifications of a user, but a polarizing film as a long polarizing film (polarizing film raw roll) is often used in common, and therefore a large number of polarizing film raw rolls are manufactured in advance, and a polarizing film product of a desired size is punched from the polarizing film raw roll as necessary in the future. When punching out a polarizing film product, it is necessary to avoid the position where the defect exists or to remove the polarizing film product in which the position where the defect exists is marked after punching out as a defective product.

Therefore, when inspecting a long polarizing film, it is necessary to detect a defect and store the position of the defect and the like as defect information.

In order to appropriately manage defect information and improve the yield of polarizing film products, patent document 1 proposes a method of inspecting a polarizing film in which identification information (information for specifying at least the position of the polarizing film in the longitudinal direction) is printed on the end in the width direction of the polarizing film and the defect information is associated with the identification information.

According to the inspection method described in patent document 1, defect information of defects generated in a polarizing film state can be appropriately managed.

However, the polarizing film has not only a defect generated in a state in which the protective film and the polarizing plate are laminated but also a defect generated in a state in which the protective film is a single body (the protective film before being laminated with the polarizing plate). Further, even if the polarizing film is inspected in a state of being a polarizing film, it may be difficult to detect a defect generated in a state of being a protective film alone.

Therefore, even if the protective film alone is inspected, the defect information of the defect detected by the inspection has not been appropriately managed in the past. Specifically, the identification information is not printed on the protective film alone and associated with the defect information.

In order to prevent occurrence of winding displacement, winding slack, blocking, and tangling when winding the protective film, the protective film may be knurled at the end in the width direction to form fine irregularities by laser marking (see, for example, patent document 2).

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5925609

Patent document 2: japanese patent No. 5578759

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a method and a system for inspecting a long optical laminate capable of appropriately associating defect information and identification information by reading both first identification information printed on a first long optical film (for example, a protective film) and second identification information printed on a second long optical film (for example, a polarizing plate) or a long optical laminate (for example, a polarizing film) in a state of the long optical laminate.

Means for solving the problems

As a result of intensive studies to solve the above problems, the present inventors have found that, by printing either one of first identification information printed on a first long optical film and second identification information printed on a second long optical film or a long optical laminate by an ink jet method and printing the other by laser lithography, or printing either one by an ink jet method using a transparent ink and printing the other by an ink jet method using a colored ink, even if the first identification information and the second identification information are overlapped, both can be read differently, and have completed the present invention.

In order to solve the above problem, the present invention provides a method for inspecting a long optical laminate, comprising: a first step of inspecting a first long optical film to acquire first defect information that is defect information of the first long optical film; a second step of printing first identification information on the end portion of the first long optical film in the width direction at predetermined intervals in the longitudinal direction of the first long optical film; a third step of storing the first defect information of the first long optical film in association with the first identification information; a fourth step of inspecting a second long optical film or a long optical laminate in which the first long optical film and the second long optical film are laminated, and acquiring second defect information that is defect information of the second long optical film or the long optical laminate; a fifth step of printing second identification information on the end portions of the second long optical film or the long optical laminate in the width direction at predetermined intervals in the longitudinal direction of the second long optical film or the long optical laminate; a sixth step of storing the second defect information of the second long optical film or the long optical laminate in association with the second identification information; the first identification information printed in the second step and the second identification information printed in the fifth step may be printed in an inkjet method and the other may be printed in a laser scribe method, or the first identification information and the second identification information may be printed in an inkjet method using a transparent ink and the other may be printed in an inkjet method using a colored ink.

In the present invention, "defect information" refers to information including at least the position of a defect. The "first identification information" is information including at least information for specifying the position of the first long optical film in the longitudinal direction. The "second identification information" is information including at least information for specifying the position in the longitudinal direction of the second long optical film or the long optical laminate.

According to the present invention, the first defect information of the first long optical film is acquired in the first step, the first identification information of the first long optical film is printed in the second step, and the first defect information and the first identification information are stored in association with each other in the third step. In addition, second defect information of the second long optical film or the long optical laminate is acquired in the fourth step, second identification information of the second long optical film or the long optical laminate is printed in the fifth step, and the second defect information and the second identification information are stored in association with each other in the sixth step.

Either one of the first identification information and the second identification information is printed by an ink jet method and the other is printed by laser lithography, or either one is printed by an ink jet method using a clear ink and the other is printed by an ink jet method using a colored ink. The transparent ink is an ink that emits fluorescence by irradiation with light, and UV ink that emits fluorescence by irradiation with ultraviolet light can be exemplified.

That is, according to the present invention, the first identification information and the second identification information are printed in any one of the following print patterns one to six.

(1) Printing a pattern 1

The first identification information: inkjet system using clear ink, second identification information: laser marking

(2) Printing pattern two

The first identification information: ink jet system using colored ink, second identification information: laser engraving

(3) Printing pattern three

The first identification information: laser engraving, second identification information: ink jet system using transparent ink

(4) Printing pattern four

The first identification information: laser engraving, second identification information: ink jet system using colored ink

(5) Printing pattern five

The first identification information: inkjet system using clear ink, second identification information: ink jet system using colored ink

(6) Print pattern six

The first identification information: ink jet system using colored ink, second identification information: ink jet system using transparent ink

Therefore, as found by the present inventors, even if the first identification information and the second identification information overlap, the two can be read separately. That is, it is possible to appropriately associate the defect information with the identification information (associate the first defect information with the first identification information, and associate the second defect information with the second identification information).

Therefore, for example, by reading the first identification information and using the correlation between the first defect information and the first identification information stored in the third step, the product can be punched while avoiding the position of the defect generated in the state of the first long optical film. Further, for example, by reading the second identification information and using the correlation between the second defect information and the second identification information stored in the sixth step, the product can be punched out while avoiding the position of the defect generated in the state of the second long optical film or the long optical laminate. In the present invention, the first to sixth steps do not necessarily have to be performed in this order, and for example, the first step may be performed after the second step is performed. Further, the fourth step may be performed after the fifth step is performed.

In the present invention, it is preferable that the first identification information is printed by an inkjet method using a clear ink in the second step, and the second identification information is printed by laser marking in the fifth step.

As described above, as a printing method of the first identification information and the second identification information, any one of the first to sixth printing patterns may be used. However, according to the results of the studies by the present inventors, the first identification information, which is the first print pattern, is printed by the ink jet method using the clear ink, and the second identification information is printed by the laser marking, so that the first identification information and the second identification information can be read most easily and distinctively.

Therefore, according to the above-described preferred method, it is possible to more appropriately associate the defect information with the identification information (associate the first defect information with the first identification information, and associate the second defect information with the second identification information).

In the present invention, it is preferable that the method further includes a seventh step of storing the first defect information of the first long optical film in association with the second identification information of the second long optical film or the long optical laminate.

According to the above preferred method, the second identification information of the second long optical film or the long optical laminate is stored in association with not only the second defect information of the second long optical film or the long optical laminate but also the first defect information of the first long optical film. In other words, the first defect information and the second defect information can be managed collectively based on the second identification information of the second long optical film or the long optical laminate.

Therefore, by cutting the end portions in the width direction of the first long optical film (for example, the knurled portion for cutting the protective film) constituting the long optical layered body after the seventh step is performed, even if the first identification information is removed, the defect information can be appropriately associated with the identification information (the first defect information and the second defect information can be associated with the second identification information).

Further, for example, by reading the second identification information, using the correlation between the second defect information and the second identification information stored in the sixth step, and using the correlation between the first defect information and the second identification information stored in the seventh step, it is possible to avoid the position of a defect generated in the state of the first long optical film and the position of a defect generated in the state of the second long optical film or the long optical laminate, and punch out a product. That is, when punching a product, the time and effort for reading the first identification information can be saved.

In the present invention, it is preferable that the method further includes an eighth step of marking a position of a defect in the long optical laminate on the basis of the first identification information and the first defect information of the first long optical film and the second identification information and the second defect information of the second long optical film or the long optical laminate.

According to the above preferred method, since the position of the defect is marked, the position of the defect can be identified even by visual observation.

The present invention can be applied to a case where the first long optical film is a protective film, the second long optical film is a polarizing plate, and the long optical laminate is a polarizing film.

In the present invention, the first long optical film may be a retardation film or a substrate coated with a liquid crystal material, and the second long optical film may be a polarizing film. Examples of the liquid crystal layer formed of a liquid crystal material applied to the substrate include liquid crystal layers functioning as phase difference plates such as an 1/4 wavelength plate and a 1/2 wavelength plate.

In the present invention, the first long optical film may be a reflective polarizing plate, and the second long optical film may be a polarizing film.

According to the findings of the present inventors, when the knurled sections are formed at the end portions of the first long optical film in the width direction, even if the first identification information is printed by an ink jet method at the portions corresponding to the knurled sections (the portions where the knurled sections are formed, or the predetermined portions where the knurled sections are formed), the first identification information may not be read so as to be distinguishable from the irregularities of the knurled sections. On the other hand, if the first identification information is printed by laser engraving on a portion corresponding to the knurled portion, it may be difficult to read the first identification information separately from the irregularities of the knurled portion.

Therefore, in the present invention, it is preferable that, when a knurled portion is formed at an end portion in the width direction of the first long optical film, the first identification information is printed by an ink jet method at a portion of the first long optical film corresponding to the knurled portion in the second step. Thus, the effective width of the first long optical film is not narrowed by printing the first identification information, and the yield can be improved.

In the present invention, it is preferable that a knurled portion is formed at an end portion in the width direction of the first long optical film, and in the fifth step, the second identification information is printed on a portion of the second long optical film or the long optical laminate located on the inner side in the width direction than the knurled portion of the first long optical film. This makes it possible to reliably read the second identification information separately from the irregularities of the knurled section.

In order to solve the above problem, the present invention also provides an inspection system for a long optical laminate, comprising: a first inspection device that inspects a first long optical film to acquire first defect information that is defect information of the first long optical film; a first printing device that prints first identification information at a predetermined interval in a longitudinal direction of the first long optical film at an end portion in the width direction of the first long optical film; a first arithmetic storage device that stores the first defect information of the first long optical film in association with the first identification information; a second inspection device that inspects a second long optical film or an optical laminate having the first long optical film and the second long optical film laminated thereon, and acquires second defect information that is defect information of the second long optical film or the long optical laminate; a second printing device that prints second identification information at predetermined intervals in a longitudinal direction of the second long optical film or the long optical laminate at ends in the width direction of the second long optical film or the long optical laminate; a second arithmetic storage device that stores the second defect information of the second long optical film or the long optical laminate in association with the second identification information; the first identification information printed by the first printing device and the second identification information printed by the second printing device may be printed by an inkjet method and the other by laser marking, or the first identification information and the second identification information may be printed by an inkjet method using a clear ink and the other by an inkjet method using a colored ink.

Effects of the invention

According to the present invention, by being able to read both the first identification information printed on the first long optical film and the second identification information printed on the second long optical film or the long optical laminate in the state of the long optical laminate, it is possible to appropriately correlate the defect information and the identification information.

Drawings

Fig. 1 is a flowchart illustrating a schematic process of a method for inspecting a long optical laminate according to a first embodiment of the present invention.

Fig. 2 is a perspective view schematically showing a schematic configuration of an inspection system for performing the first to third steps S2 to S4 shown in fig. 1.

Fig. 3 is a perspective view schematically showing a schematic configuration of an inspection system for performing the fourth step S6 to the sixth step S8 shown in fig. 1.

Fig. 4 is a perspective view schematically showing the schematic configuration of an inspection system for executing the seventh step S9 shown in fig. 1.

Fig. 5 is a side view schematically showing a schematic configuration example of the first reader 9 and the second reader 10 shown in fig. 4(a side view as viewed in the width direction of the long optical laminate F2).

Fig. 6 is a perspective view schematically showing a schematic configuration of an inspection system for executing 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) shown in fig. 1.

Fig. 7 is a diagram showing an example of printing the first identification information M and the second identification information N in the inspection method for a long optical laminate according to the first embodiment of the present invention.

Fig. 8 shows an example of the result of reading the first identification information M of the long optical laminate F2 shown in fig. 7 by the first reading device 9.

Fig. 9 shows an example of the result of reading the second identification information N of the long optical laminate F2 shown in fig. 7 by the second reading device 10.

Fig. 10 is a flowchart partially showing a schematic process of an inspection method according to a second embodiment of the present invention.

Fig. 11 is a flowchart showing a schematic process of the inspection method according to the third embodiment of the present invention (a schematic process performed in the process of manufacturing the first long optical film F1).

Fig. 12 is a flowchart showing a schematic process of the inspection method according to the third embodiment of the present invention (a schematic process performed in the process of manufacturing the second long optical film F2).

Fig. 13 is a flowchart showing a schematic process of the inspection method according to the third embodiment of the present invention (a schematic process performed in the process of manufacturing a long optical laminate).

Fig. 14 is a cross-sectional view schematically showing the state of each film in the process of manufacturing the first long optical film F1 shown in fig. 11.

Fig. 15 is a cross-sectional view schematically showing the state of each film in the process of manufacturing the second long optical film F2 shown in fig. 12.

Fig. 16 is a cross-sectional view schematically showing the state of each film in the process of manufacturing the long optical laminate shown in fig. 13.

Fig. 17 is an explanatory view for explaining a print pattern in the inspection method of a long optical laminate according to the fourth embodiment of the present invention.

Detailed Description

< first embodiment >

Hereinafter, an inspection method for a long optical laminate (hereinafter, referred to simply as an "inspection method" where appropriate) and an inspection system for a long optical laminate (hereinafter, referred to simply as an "inspection system" where appropriate) according to a first embodiment of the present invention will be described with reference to the drawings as appropriate.

The long optical laminate to be inspected in the inspection method according to the first embodiment is a film in which a first long optical film and a second long optical film are laminated. In the first embodiment, a case where the first long optical film is a protective film, the second long optical film is a polarizing plate, the long optical laminate is a polarizing film, the long optical laminate is inspected to obtain second defect information, and the long optical laminate is printed with second identification information will be described as an example. First, a specific example of a long optical laminate (polarizing film) will be described.

[ Long optical laminate ]

The polarizing film as a long optical laminate is produced by a production method including (a) a step of drying a polyvinyl alcohol film subjected to dyeing treatment, crosslinking treatment, and stretching treatment to produce a polarizing plate as a second long optical film, (B) a step of bonding a protective film as a first long optical film to one side or both sides of the second long optical film (polarizing plate), and (C) a step of performing heat treatment after bonding.

The respective treatments of the dyeing treatment, the crosslinking treatment, and the stretching treatment of the polyvinyl alcohol film are not necessarily performed separately, and may be performed simultaneously, and the order of the respective treatments may be arbitrary. As the polyvinyl alcohol film, a polyvinyl alcohol film subjected to a swelling treatment may be used. In general, a polyvinyl alcohol film is immersed in a solution containing iodine or a dichroic dye, dyed by adsorbing iodine or a dichroic dye, then washed, uniaxially stretched at a stretching ratio of 3 to 7 times in a solution containing boric acid, borax, or the like, and then dried. It is particularly preferable that the film is stretched in a solution containing iodine or a dichroic dye, and then further stretched in a solution containing boric acid, borax, or the like (two-stage stretching), and then dried, because the orientation of iodine is increased and the polarization degree characteristics are improved.

Examples of the polyvinyl alcohol polymer constituting the polyvinyl alcohol film include a polyvinyl alcohol polymer obtained by polymerizing vinyl acetate and then saponifying the polymerized vinyl acetate, and a polyvinyl alcohol polymer 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 polymerization degree can be used, and is preferably 1000 or more, and more preferably 2000 to 5000. The saponification degree of the polyvinyl alcohol polymer is preferably 85 mol% or more, and more preferably 98 to 100 mol%.

The thickness of the second long optical film (polarizing plate) to be produced is usually 5 to 80 μm, but is not limited thereto, and a method for adjusting the thickness of the second long optical film (polarizing plate) is not particularly limited, and a usual method such as tenter, roll stretching, or rolling may be used.

The second long optical film (polarizing plate) and the first long optical film (protective film) may be bonded to each other by, for example, an adhesive agent made of a vinyl alcohol polymer, or an adhesive agent made of a water-soluble crosslinking agent of a vinyl alcohol polymer such as at least boric acid, borax, glutaraldehyde, melamine, or oxalic acid. The adhesive layer in which the second long optical film (polarizing plate) and the first long optical film (protective film) are bonded is formed as a coating dry layer of an aqueous solution, and other additives, an acid, and other catalysts may be added as needed in the preparation of the aqueous solution.

As the first long optical film (protective film) to be bonded to one side or both sides of the second long optical film (polarizing plate), an appropriate transparent film can be used. Among them, a film made of a polymer excellent in transparency, mechanical strength, thermal stability, moisture barrier property, and the like is preferably used. Examples of the polymer include an acetate resin such as triacetylcellulose, a polyester resin such as polycarbonate resin, polyarylate, and polyethylene terephthalate, a polyimide resin, a polysulfone resin, a polyether sulfone resin, a polystyrene resin, a polyolefin resin such as polyethylene and polypropylene, a polyvinyl alcohol resin, a polyvinyl chloride resin, a polynorbornene resin, a (meth) acrylic resin, a polymethyl methacrylate resin, and a liquid crystal polymer. The film can be produced by any of a casting method, a rolling method, and an extrusion method.

Further, there can be mentioned a polymer film described in Japanese patent laid-open No. 2001-343529 (WO01/37007), for example, a resin composition containing (A) a thermoplastic resin having a substituted and/or unsubstituted imide group in a side chain and (B) a thermoplastic resin having a substituted and/or unsubstituted phenyl group and a nitrile group in a side chain. Specifically, a film of a resin composition containing an alternating copolymer of isobutylene and N-methylmaleimide and an acrylonitrile-styrene copolymer can be mentioned. As the film, a film made of a mixed extrusion product of a resin composition or the like can be used. These films have a small phase difference and a small photoelastic coefficient, and therefore, can eliminate problems such as unevenness caused by deformation of a long optical laminate (polarizing film), and have excellent humidification durability because of a small moisture permeability.

In addition, the first long optical film (protective film) is preferably as colorless as possible. Therefore, it is preferable to use a first long optical film (protective film) having a phase difference value in the film thickness direction of-90 nm to +75nm, which is expressed by Rth ═ [ (nx + ny)/2-nz ] & d (where nx and ny are principal refractive indices in the film plane, nz is a refractive index in the film thickness direction, and d is the film thickness). By using the first long optical film (protective film) having a retardation value (Rth) in the thickness direction of-90 nm to +75nm, the coloration (optical coloration) of the long optical laminate (polarizing film) caused by the first long optical film (protective film) can be substantially eliminated. The retardation value (Rth) in the thickness direction is more preferably from-80 nm to +60nm, and particularly preferably from-70 nm to +45 nm.

As the first long optical film (protective film), a (meth) acrylic resin is preferable from the viewpoint of polarization characteristics, durability, and the like. In addition, an acetate-based resin such as triacetyl cellulose is preferable, and a triacetyl cellulose film whose surface has been saponified with an alkali or the like is particularly preferable. When the first long optical film (protective film) is bonded to both sides of the second long optical film (polarizing plate), the first long optical film (protective film) made of different polymers on the front surface and the back surface may be used.

The thickness of the first long optical film (protective film) is arbitrary, but is usually 500 μm or less, preferably 1 to 300 μm, and particularly preferably 5 to 200 μm for the purpose of thinning the long optical laminate (polarizing film).

The first long optical film (protective film) may be subjected to surface treatment such as hard coating treatment, antireflection treatment, treatment for preventing blocking, diffusion, or antiglare purpose, as long as the object of the present invention is not impaired. The hard coat treatment is a treatment performed for the purpose of preventing damage or the like to the surface of the long optical laminate (polarizing film), and may be formed, for example, by adding a cured film having excellent hardness, smoothness, and the like, which is formed of an appropriate ultraviolet-curable resin such as silicone, to the surface of the first long optical film (protective film).

On the other hand, the antireflection treatment is a treatment performed for the purpose of preventing reflection of external light on the surface of the long optical laminate (polarizing film), and can be realized by formation of an antireflection film or the like according to the related art. The anti-blocking treatment is performed to prevent adhesion to the adjacent layer, and the anti-glare treatment is performed to prevent the surface of the long optical laminate (polarizing film) from reflecting external light and to prevent visual confirmation of the light transmitted through the long optical laminate (polarizing film), and may be formed by imparting a fine uneven structure to the surface of the first long optical film (protective film) in an appropriate manner, for example, by a roughening method such as a sandblasting method or an embossing method, or a blending method of transparent fine particles.

Examples of the transparent fine particles include silica or alumina having an average particle diameter of 0.5 to 20 μm, titania or zirconia, tin oxide or indium oxide, cadmium oxide or antimony oxide, and inorganic fine particles having conductivity may be used, and organic fine particles composed of crosslinked or uncrosslinked polymer particles may be used. The amount of the transparent fine particles to be used is usually 2 to 70 parts by mass, particularly usually 5 to 50 parts by mass, based on 100 parts by mass of the transparent resin.

Further, the antiglare layer containing transparent microparticles may be provided as the transparent protective layer itself, or as a coating layer on the surface of the transparent protective layer. The antiglare layer may also serve as a diffusion layer (viewing angle compensation function or the like) for diffusing the transmitted light of the long optical laminate (polarizing film) to expand the viewing angle. The antireflection layer, the release layer, the diffusion layer, the antiglare layer, and the like may be provided as an optical layer made of a sheet or the like provided with these layers, separately from the transparent protective layer.

[ inspection method of the first embodiment ]

The following describes the inspection method according to the first embodiment.

Fig. 1 is a flowchart illustrating a schematic process of the inspection method according to the first embodiment. As shown in fig. 1, the inspection method of the first embodiment includes: steps S1 to S4 executed in the step of manufacturing the first long optical film (protective film); steps S5 to S12 executed in the step of producing a long optical laminate (polarizing film). Hereinafter, the respective steps will be described in order.

[ Process to be executed in the Process for producing the first Long optical film ]

In the first long optical film manufacturing step, the first step S2 to the third step S4 are performed. In the first embodiment, the knurling process S1 is performed.

(knurling step S1)

In the knurling step S1, the widthwise end portions of the first long optical film are knurled to form knurled portions. The details of knurling are well known as described in patent document 2, for example, and therefore, a detailed description thereof will be omitted.

(first step S2)

Fig. 2 is a perspective view schematically showing the schematic configuration of the inspection system for performing the first step S2 to the third step S4.

As shown in fig. 2, in the first step S2, the first inspection apparatus 1 included in the inspection system 100 inspects the first long optical film F1 which is transported in a roll-to-roll manner (transported in a direction indicated by a thick arrow in fig. 2) by the transport rollers R, and acquires first defect information which is defect information of the first long optical film F1.

The first inspection apparatus 1 includes: an imaging unit 1a disposed to face the surface of the first long optical film F1; and an image processing unit 1b electrically connected to the imaging unit 1a, for performing appropriate image processing on the captured image of the surface of the first long optical film F1 acquired by the imaging unit 1 a. As the imaging unit 1a, a line sensor in which imaging elements are arranged linearly along the width direction of the first long optical 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 unit 1a is equal to or greater than the effective width (width used in the product) of the first long optical film F1. The image processing section 1b extracts a pixel region corresponding to a defect existing in the first long optical film F1 by performing known image processing such as binarization on the captured image. The image processing unit 1b specifies the position of the defect (coordinates of the pixel region corresponding to the defect) in the captured image, and acquires information including at least the specified position of the defect as first defect information. The acquired first defect information is input to the first arithmetic storage device 4 included in the inspection system 100.

(second step S3)

In the second step S3, the first printing apparatus 2 included in the inspection system 100 prints the first identification information M at the end portions (preferably, knurling processing portions) in the width direction of the first long optical film F1 at predetermined intervals (for example, equal intervals of 1M) in the longitudinal direction of the first long optical film F1. Fig. 2 shows an example in which the first identification information M1 to M3 are printed in order from the front end side (downstream side in the conveyance direction) of the first long optical film F1.

The first identification information M is information including at least information for specifying the longitudinal position of the first long optical film F1. The first identification information M is, for example, a numerical value (the position in the longitudinal direction of the first long optical film F1 is determined by the numerical value) which sequentially increases or decreases from the distal end side of the first long optical film F1. The first identification information M may include various additional information such as the date and time of printing, the manufacturing number of the first long optical film F1, and the type of printing process, in addition to information for identifying the longitudinal position of the first long optical film F1.

In the first embodiment, the first operation storage device 4 controls the printing of the first identification information M by the first printing device 2. Specifically, the amount of movement of the first long optical film F1 in the conveyance direction is measured by the length measuring device 3 using a rotary encoder or the like, and is input to the first arithmetic storage device 4. The first arithmetic storage device 4 transmits a control signal to the first printing device 2 at predetermined intervals based on the movement amount input from the length measuring device 3, and causes the first printing device 2 to print the first identification information M at predetermined intervals.

In the first embodiment, the case where the first arithmetic storage device 4 further has a function of controlling the first printing device 2 has been described as an example, but the present invention is not limited to this, and a control device different from the first arithmetic storage device 4 may be used to control the first printing device 2.

The first printing apparatus 2 of the first embodiment prints the first identification information M in an ink jet manner. The first printing apparatus 2 according to the first embodiment preferably prints the first identification information M by an inkjet method using clear ink. Specifically, in the first embodiment, the first identification information M is printed in an ink jet system using UV ink that emits fluorescence by irradiation of ultraviolet rays as clear ink.

As the first printer 2, for example, an inkjet printer "VJ 1000 series" manufactured by Videojet corporation and an inkjet printer "Gravis UX series" manufactured by hitachi corporation can be used.

(third step S4)

In the third step S4, the first arithmetic and storage unit 4 stores the first defect information of the first long optical film F1 in association with the first identification information M. Specifically, the following is described.

For example, assume that the first inspection apparatus 1 detects the defect D1 shown in fig. 2, specifies the position of the defect D1 (the coordinates of the pixel region corresponding to the defect D1) in the captured image, and inputs the specified position to the first arithmetic storage device 4 as first defect information. Since the amount of movement of the first long optical film F1 in the conveyance direction is input from the length measuring device 3 to the first arithmetic storage device 4, the first arithmetic storage device 4 can grasp how much the first long optical film F1 has moved in the conveyance direction between the time when the defect D1 is detected (the time when the coordinates of the pixel region corresponding to the defect D1 in the captured image are determined) and the time when the first identification information M is printed by the first printing device 2. Based on the amount of movement of the first long optical film F1 between these two points in time and the coordinates of the pixel region corresponding to the defect D1 in the captured image, the first arithmetic and storage device 4 can calculate the distance (distance along the longitudinal direction of the first long optical film F1) X1 from the predetermined first identification information M (the first identification information M3 in the example shown in fig. 2) to the defect D1. Further, the first arithmetic and storage device 4 can calculate the distance Y1 from the edge of the first long optical film F1 in the width direction to the defect D1 (the distance along the width direction of the first long optical film F1) based on the coordinates of the pixel region corresponding to the defect D1 in the captured image. The first arithmetic storage device 4 stores at least the first identification information M (M3) in association with the coordinates (X1, Y1) of the defect D1 with reference to the first identification information M (M3).

[ Processes to be carried out in the Process for producing a Long optical laminate ]

The first long optical film F1 (the first long optical film on which the first identification information M is printed by the inkjet method in the knurling processing section) produced in the above-described production process was wound into a roll shape as a roll. The first long optical film F1 as a roll is conveyed to the process of manufacturing a long optical laminate. In the step of producing the long optical laminate, the first long roll of the optical film F1 is used.

As shown in fig. 1, the process for producing the long optical laminate according to the first embodiment includes the process of No.1 and the process of No. 2. In the step of manufacturing the long optical laminate according to the first embodiment, after the fourth step S6 to the seventh step S9 are performed in the step No.1, the fourth step S11 and the sixth step S12 are performed again in the step No. 2. In the process for producing the long optical laminate according to the first embodiment, the bonding step S5 is performed in the step No.1, and the reading step S10 is performed in the step No. 2.

(bonding step S5)

In the No.1 step, the first long optical film F1 (protective film) was fed from a roll, and the second long optical film (polarizing plate) was fed from a roll. Then, in the laminating step S5, the first long optical film F1 is laminated on one side or both sides of the second long optical film via an adhesive or the like as described above, to obtain a long optical laminate F2 (polarizing film) in which the first long optical film F1 and the second long optical film are laminated.

(fourth Process S6)

Fig. 3 is a perspective view schematically showing a schematic configuration of an inspection system for executing the fourth step S6 to the sixth step S8.

As shown in fig. 3, in the fourth step S6, the second inspection device 5 included in the inspection system 100 inspects the long optical layered body F2 that is transported in a roll-to-roll manner (transported in the direction indicated by the thick arrow in fig. 3) by the transport rollers R, and acquires second defect information that is defect information of the long optical layered body F2.

The second inspection apparatus 5 includes an imaging unit 5a and an image processing unit 5b, as in the first inspection apparatus 1 shown in fig. 2, and has the same functions as the first inspection apparatus 1, and therefore, a detailed description thereof is omitted here. The second inspection device 5 specifies the position of the defect (coordinates of the pixel region corresponding to the defect) in the captured image, and acquires information including at least the specified position of the defect as second defect information. The acquired second defect information is input to the second arithmetic and storage device 8 included in the inspection system 100.

(fifth step S7)

In the fifth step S7, the second printing apparatus 6 included in the inspection system 100 prints the second identification information N at predetermined intervals (for example, equal intervals of 1 m) in the longitudinal direction of the long optical laminate F2 at the end portions in the width direction of the long optical laminate F2 (preferably, at the portions of the long optical laminate F2 located on the inner side in the width direction than the knurled portions of the first long optical film F1). Fig. 3 shows an example in which the second identification information N1 to N3 are printed in order from the distal end side (downstream side in the conveying direction) of the long optical laminate F2. Although the first identification information M is actually printed on the first long optical film F1 constituting the long optical laminate F2, the first identification information M is not shown in fig. 3 for convenience.

The second identification information N is different from the first identification information M including at least information identifying the position in the longitudinal direction of the long optical laminate F2, and is the same as the first identification information M except for the information identifying the position in the longitudinal direction of the first long optical film F1, and therefore, a detailed description thereof is omitted.

In the first embodiment, the second identification information N printed on the long optical laminate F2 is printed on the same first long optical film F1 as the first long optical film F1 on which the first identification information M is printed, but the present invention is not limited thereto.

For example, when the long optical laminate F2 (polarizing film) is formed by laminating the first long optical film F1 (protective film) on both sides of the second long optical film (polarizing plate), the first identification information M may be printed on one of the first long optical films F1 (protective film) and the second identification information N may be printed on the other of the first long optical films F1 (protective film) on which the first identification information M is not printed.

For example, in the case where the first long optical film F1 (protective film) is bonded to both sides of the second long optical film (polarizing plate), and the retardation film is bonded to one of the first long optical films to form the long optical laminate F2 (polarizing film with a retardation function), the first identification information M may be printed on the other first long optical film F1 (protective film), and the second identification information N may be printed on the retardation film.

The printing of the second identification information N by the second printing apparatus 6 is controlled by the second arithmetic storage device 8, similarly to the printing of the first identification information M by the first printing apparatus 2 controlled by the first arithmetic storage device 4. The specific control contents are the same as the control of printing the first identification information M by the first printing apparatus 2, and therefore, a detailed description thereof is omitted here.

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

(sixth Process S8)

In the sixth step S8, the second arithmetic and storage unit 8 stores the second defect information of the long optical laminate F2 in association with the second identification information N. Specifically, although the first arithmetic and storage device 4 is a procedure similar to the case where the first defect information of the first long optical film F1 is stored in association with the first identification information M, detailed description thereof will be omitted, but the second arithmetic and storage device 8 stores at least the second identification information N (the second identification information N3 in the example shown in fig. 3) in association with the coordinates (X2, Y2) of the defect D2 with reference to the second identification information N (N3) using the amount of movement in the transport direction of the long optical laminate F2 input from the length measuring instrument 7 having the same configuration as the length measuring instrument 3.

(seventh Process S9)

Fig. 4 is a perspective view schematically showing a schematic configuration of an inspection system for executing the seventh step S9.

In the seventh step S9, the second arithmetic and memory device 8 stores the first defect information of the first long optical film F1 in association with the second identification information of the long optical laminate F2. Specifically, a first reading device 9 configured to read first identification information M (in fig. 4, first identification information M1 to M3) and a second reading device 10 configured to read second identification information N (in fig. 4, second identification information N1 to N3) are provided, and the first identification information M read by the first reading device 9 and the second identification information N read by the second reading device 10 are input to the second arithmetic storage device 8. Here, the second arithmetic storage device 8 previously inputs and stores the association between the first defect information stored in the first long optical film F1 of the first arithmetic storage device 4 and the first identification information M (the relationship between the first identification information M and the coordinates of the defect with reference to the first identification information M). The input of the first defect information and the first identification information M may be performed by electrically connecting the first arithmetic storage unit 4 and the second arithmetic storage unit 8 and transmitting the information from the first arithmetic storage unit 4 to the second arithmetic storage unit 8, or may be performed by manually inputting the information downloaded from the first arithmetic storage unit 4 to the second arithmetic storage unit 8. Further, the amount of movement of the long optical layered body F2 in the transport direction is input to the second arithmetic and memory device 8 from the length measuring instrument 11 having the same configuration as the length measuring instrument 3.

The second arithmetic storage device 8 can grasp how much the long optical laminate F2 has moved in the conveying direction between the time when the first identification information M is read by the first reading device 9 (the time when the first identification information M is input to the second arithmetic storage device 8) and the time when the second identification information N is read by the second reading device 10 (the time when the second identification information N is input to the second arithmetic storage device 8) based on the amount of movement of the long optical laminate F2 in the conveying direction input from the length measuring device 11. Based on the amount of movement of the long optical layered body F2 between these two times, the second arithmetic and storage device 8 can calculate the positional shift of the first identification information M and the second identification information N along the longitudinal direction of the long optical layered body F2 (the positional shift dX of the first identification information M3 and the second identification information N3 in the example shown in fig. 4).

Therefore, the second arithmetic and storage unit 8 can store the first defect information of the first long optical film F1 and the second identification information N of the long optical layered body F2 in association with each other based on the association between the first defect information of the first long optical 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 with reference to the second identification information N. In this way, by executing the seventh step S9, the first defect information and the second defect information can be managed collectively based on the second identification information N of the long optical laminate F2.

The long optical laminate F2 subjected to the seventh step S9 is wound in a roll shape and is conveyed to the No.2 step.

Fig. 5 is a side view schematically showing a schematic configuration example of the first reader 9 and the second reader 10 (a side view as viewed in the width direction of the long optical laminate F2). 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. 5a, the first reading device 9 includes a UV illumination 91 that emits ultraviolet rays, and an imaging unit (area sensor) 92. The first identification information M printed with the transparent ink (UV ink) fluoresces when the ultraviolet light emitted from the UV illumination 91 is irradiated to the surface of the long optical laminate F2. Thus, in the captured image obtained by the imaging unit 92 disposed on the same side as the UV illumination 91 (the upper side in the example shown in fig. 5 a) with respect to the surface of the long optical layered body F2, the pixel region corresponding to the first identification information M is brightened (the pixel region corresponding to the second identification information N is darkened similarly to the background), and the first identification information M can be read separately from the second identification information N.

The UV illumination 91 may be, for example, UV illumination that emits ultraviolet light having a wavelength of about 200 to 400nm, preferably ultraviolet light having a wavelength of about 365 nm. Further, as the imaging means 92, for example, a region sensor with a high-speed shutter having a shutter speed (exposure time) of about 30 to 150 μ sec can be used.

As shown in fig. 5(b), the second reading device 10 includes: an illumination 101 that is disposed on one side (lower side in the example shown in fig. 5(b)) of the surface of the long optical laminate F2 and emits a parallel light flux; the imaging unit (area sensor) 102 is disposed on the other side (upper side in the example shown in fig. 5b) of the surface of the long optical layered body F2, and receives light transmitted through the long optical layered body F2. The parallel light beam emitted from the illumination 101 and irradiated to the surface of the long optical layered body F2 is scattered by the second identification information N printed by laser marking. Thus, in the captured image acquired by the imaging unit 102, the pixel region corresponding to the second identification information N is darkened (the pixel region corresponding to the first identification information M is brightened as in the background), and the second identification information N can be read separately from the first identification information M.

Although the detailed description is omitted, when the first identification information M is printed using a normal color ink, by using, as a reading device for reading the first identification information M, a reading device that irradiates diffused light instead of the illumination 101 shown in fig. 5(b), a pixel region corresponding to the first identification information M in the captured image acquired by the imaging unit 102 is darkened (a pixel region corresponding to the second identification information N is brightened as in the background), and the first identification information M can be read separately from the second identification information N.

(reading step S10)

In the No.2 step, the long optical laminate F2 wound in a roll shape was fed out. Then, the reading process S10 is first performed.

Fig. 6 is a perspective view schematically showing the schematic configuration of the inspection system for executing the reading step S10, the second fourth step S11, and the sixth step S12 (the fourth step and the sixth step after the execution of the seventh step S9). Although the first identification information M is actually printed on the first long optical film F1 constituting the long optical laminate F2, the first identification information M is not shown in fig. 6 for convenience.

As shown in fig. 6, in the reading step S10, the second identification information N is read by the second reading device 12 having the same configuration as the second reading device 10 (see fig. 4 and 5b) included in the inspection system 100. The read second identification information N is input to the second arithmetic storage device 8.

(fourth Process (second) S11)

In the second fourth step S11, the second inspection device 13 (the image pickup unit 13a and the image processing unit 13b) having the same configuration as the second inspection device 5 included in the inspection system 100 inspects the long optical layered body F2 that is transported in a roll-to-roll manner (transported in the direction indicated by the thick arrow in fig. 6) by the transport rollers R, and acquires second defect information that is defect information of the long optical layered body F2. The acquired second defect information is input to the second arithmetic storage device 8.

(sixth Process (second) S12)

In the second sixth step S12, the second arithmetic and memory device 8 stores the second defect information of the long optical layered body F2 acquired by the second inspection device 13 in association with the second identification information N read by the second reading device 12. Specifically, the second arithmetic and storage device 8 uses the amount of movement in the transport direction of the long optical laminate F2 input from the length measuring device 14 having the same configuration as the length measuring device 3 to grasp how much the long optical laminate F2 has moved in the transport direction between the time when the second reading device 12 reads the second identification information N and the time when the defect is detected by the second inspection device 13 (the time when the coordinates of the pixel region corresponding to the defect in the captured image are specified), and stores at least the second identification information N and the coordinates of the defect with reference to the second identification information N in association with each other.

In the first embodiment, the case where the inspection is performed twice in the manufacturing process of the long optical laminate F2 (the inspection by the second inspection apparatus 5, the inspection by the second inspection apparatus 13) has been described as an example, but when the inspection is performed three or more times, the reading step S10, the fourth step S11, and the sixth step S12 may be repeatedly performed in the second and subsequent inspections.

According to the inspection method of the first embodiment described above, since the first identification information M is printed by an ink jet method and the second identification information N is printed by laser scribing, even if the first identification information M and the second identification information N overlap, as found by the present inventors, it is possible to read them differently. That is, it is possible to appropriately associate the defect information with the identification information (associate the first defect information with the first identification information M (and further the second identification information N), and associate the second defect information with the second identification information N).

Further, for example, by reading the second identification information N, using the association between the second defect information and the second identification information N stored in the sixth steps S8 and S12, and using the association between the first defect information and the second identification information N stored in the seventh step S9, it is possible to punch out the product while avoiding the position of the defect generated in the state of the first long optical film F1 and the position of the defect generated in the state of the long optical laminated body F2.

However, the inspection method of the present invention is not limited to the method in which the first identification information M is printed by an ink jet method and the second identification information N is printed by laser engraving. Even if one of the first identification information M and the second identification information N is printed by an ink jet method, the other is printed by laser engraving, or either one is printed by an ink jet method using a clear ink, and the other is printed by an ink jet method using a colored ink, the first identification information M and the second identification information N can be read separately.

In a preferred embodiment, the inspection method according to the first embodiment may further include an eighth step (not shown in fig. 1) of marking the position of the defect in the long optical laminate F2 based on the correlation between the first identification information M (and further the second identification information N of the long optical laminate F2) and the first defect information of the first long optical film F1 and the correlation between the second identification information N of the long optical laminate F2 and the second defect information. Specifically, the second identification information N may be read, and an ink-jet marking or a marking using a universal pen similar to that described in patent document 1 may be performed at the position of the defect included in the first defect information and the second defect information. Since the marking is performed at the position of the defect by including the eighth step of performing the marking, the position of the defect can be specified even by visual inspection.

Fig. 7 is a diagram showing an example of printing the first identification information M and the second identification information N based on the inspection method of the first embodiment. Fig. 7 shows an example of a long optical laminate F2 (polarizing film) in which a protective film made of triacetyl cellulose (TAC) and a protective film made of acrylic acid are used as the first long optical films F1, and the first long optical films F1 are bonded to both sides of a polarizing plate as a second long optical film. In the example shown in fig. 7, after the first identification information M is printed on the acrylic protective film by the ink jet method of the transparent ink (UV ink), the acrylic protective film and the TAC protective film are respectively attached to both sides of the polarizing plate, and then the second identification information N is printed on the TAC protective film side by laser marking. The circular irregularities shown in fig. 7 are knurled portions formed at the end portions in the width direction of the acrylic protective film, and the rhombic irregularities are knurled portions formed at the end portions in the width direction of the TAC protective film.

The captured image shown in fig. 7 is obtained when the long optical laminate F2 is illuminated by both the UV illumination 91 provided in the first reading device 9 and the illumination 101 provided in the second reading device 10.

Fig. 8 shows an example of the result of reading the first identification information M of the long optical laminate 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 region corresponding to the first identification information M is brightened (the pixel region corresponding to the second identification information N is darkened similarly to the background), and it is understood that the first identification information M can be read separately from the second identification information N.

Fig. 9 shows an example of the result of reading the second identification information N of the long optical laminate 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 region corresponding to the second identification information N is darkened (the pixel region corresponding to the first identification information M is brightened similarly to the background), and it is understood that the second identification information N can be read separately from the first identification information M.

In the first embodiment, the example in which the first identification information M is printed on the first long optical film F1 in the second step S3 after the knurling step S1 is performed (after the knurling portion is formed on the first long optical film F1) is described, but the present invention is not limited to this. The first identification information M may also be printed at a predetermined site where the knurled sections are to be formed before the knurled sections are formed (i.e., the knurled sections are formed after the first identification information M is printed).

In the first embodiment, the case where the inspection of the long optical laminate F2 is performed a plurality of times has been described as an example, but the present invention is not limited to this, and the inspection of the long optical laminate F2 may be performed only once. In this case, the reading step S10, the fourth step (second step) S11, and the sixth step (second step) S12 shown in fig. 1 are not required. However, when punching the product while avoiding the position of the defect generated in the state of the first long optical film F1 and the position of the defect generated in the state of the long optical laminate F2, or when performing the eighth step of marking the position of the defect of the long optical laminate F2, the reading step S10 is necessary.

In the first embodiment, the case where the inspection of the first long optical film F1 is performed only once has been described as an example, but the present invention is not limited to this, and may be performed a plurality of times in the same manner as the inspection of the long optical laminate F2. In this case, in the second and subsequent inspections, after the third step S4 shown in fig. 1, it is necessary to repeat the reading step of reading the first identification information M, the step of acquiring the first defect information in the same manner as in the first step S2, and the step of storing the first defect information in association with the first identification information M in the same manner as in the third step S4.

In the first embodiment, the case where the seventh step S9 is executed to centrally manage the first defect information and the second defect information based on the second identification information N of the long optical layered body F2 has been described as an example, but the present invention is not limited to this. Instead of performing the seventh step S9, the first defect information may be managed based on the first identification information M and the second defect information may be managed based on the second identification information N. Specifically, for example, by reading the first identification information M, punching the product while avoiding the position of the defect generated in the state of the first long optical film F1 using the correlation between the first defect information stored in the third step S4 and the first identification information M, and by reading the 2 nd identification information N, punching the product while avoiding the position of the defect generated in the state of the long optical laminate F2 using the correlation between the second defect information stored in the 6 th step S8 and the second identification information N.

In the first embodiment, the case where the first long optical film F1 is a protective film, the second long optical film is a polarizing plate, and the long optical laminate F2 is a polarizing film is described as an example, but the present invention is not limited thereto. For example, the first long optical film F1 may be a retardation film, and the second long optical film may be a polarizing plate. The first long optical film F1 may be a conductive film such as a retardation film, a reflective polarizing plate, an antireflection film, or an ITO film, for example, a window film made of polyimide or the like, and the second long optical film may be a polarizing film (a laminate of a polarizing plate and a protective film).

< second embodiment >

The method for inspecting a long optical laminate according to the second embodiment of the present invention is different from the first embodiment in that a protective film as the first long optical film F1 is subjected to a surface treatment such as an antiglare treatment, and the inspection is performed before and after the surface treatment. Hereinafter, the inspection method according to the second embodiment will be mainly described about differences from the first embodiment, and the description about the same differences from the first embodiment will be omitted as appropriate.

Fig. 10 is a flowchart partially showing a schematic process of the inspection method of the second embodiment. Specifically, fig. 10 shows a process added to the inspection method of the first embodiment shown in fig. 1 by the inspection method of the second embodiment.

The inspection method of the second embodiment includes, in addition to steps S1 to S12 included in the inspection method of the first embodiment, step S20 surrounded by a broken line between the third step S4 and the bonding step S5 performed in the step of manufacturing the first long optical film F1, as shown in fig. 10. Specifically, the inspection method of the second embodiment includes steps S21 to S24. Hereinafter, the respective steps will be described in order.

(surface treatment Process S21)

In the surface treatment step S21, after the third step S4 is performed, the first long optical film F1 (protective film) wound in a roll shape is fed out and subjected to surface treatment. Examples of the surface treatment performed in the surface treatment step S21 include a hard coat treatment, an antireflection treatment, and an anti-sticking treatment in addition to the antiglare treatment.

(reading step S22)

In the reading step S22, in the reading apparatus having the same configuration as the first reading apparatus 9 of the first embodiment, the first identification information M of the first long optical film F1 after the surface treatment, which is conveyed by the conveying roller in a roll-to-roll manner, is read. The read first identification information M is input to the first arithmetic storage device 4.

(first step (second step) S23)

In the second first step S23, the inspection apparatus having the same configuration as the first inspection apparatus 1 (the image pickup unit 1a and the image processing unit 1b) of the first embodiment inspects the surface-treated first long optical film F1 conveyed by the conveying roller in a roll-to-roll manner, and acquires first' defect information which is defect information of the surface-treated first long optical film F1. The acquired first' defect information is input to the first arithmetic storage device 4.

(third step (second step) S24)

In the second third step S24, the first arithmetic and storage unit 4 stores the first' defect information of the first long optical film F1 after the surface treatment, which was obtained in the second first step S23, in association with the first identification information M read in the reading step S22. In the first arithmetic storage device 4, since the third step S4 stores the first defect information of the first long optical film F1 before the surface treatment in association with the first identification information M, the first arithmetic storage device 4 stores the first 'defect information of the first long optical film F1 after the surface treatment in association with the first identification information M while covering the first defect information with the first' defect information.

Specifically, the first arithmetic storage unit 4 uses the movement amount of the first long optical film F1 after surface processing, which is input from the length measuring device having the same configuration as the length measuring device 3, in the transport direction, and grasps how much the first long optical film F1 after surface processing has moved in the transport direction between the time when the first identification information M is read by the reading device and the time when the defect is detected by the inspection device (the time when the coordinates of the pixel region corresponding to the defect in the captured image are determined), and stores at least the first identification information M and the coordinates of the defect with reference to the first identification information M in association with each other.

In the inspection method according to the second embodiment described above, the first identification information M and the second identification information N are printed in any one of the above-described print patterns one to six. Therefore, according to the inspection method of the second embodiment, as in the first embodiment, even if the first identification information M and the second identification information N overlap, both can be read separately. That is, it is possible to appropriately associate the defect information with the identification information (associate the first defect information with the first identification information M (and further the second identification information N), and associate the second defect information with the second identification information N).

Further, for example, 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 steps S8 and S12 and the association between the first defect information and the second identification information N stored in the seventh step S9, the product can be punched while avoiding the position of the defect generated in the state of the first long optical film F1 (both the first long optical films before and after the surface treatment) and the position of the defect generated in the state of the long optical laminate F2.

< third embodiment >

The method for inspecting a long optical laminate according to the third embodiment of the present invention is different from the first embodiment in that the first long optical film F1 is a substrate to which a liquid crystal material is applied, the inspection is performed before and after the liquid crystal material is applied to the first long optical film F1, the second long optical film is a polarizing film, the second long optical film is inspected to obtain second defect information, and the second identification information N is printed on the second long optical film. Hereinafter, the inspection method according to the third embodiment will be mainly described about differences from the first embodiment, and the description about the same differences from the first embodiment will be omitted as appropriate. In the first embodiment, F2 is used as a reference numeral for the long optical laminate, but F2 is used as a reference numeral for the second long optical film in the third embodiment.

Fig. 11 to 13 are flowcharts illustrating a schematic process of the inspection method according to the third embodiment. Fig. 11 is a flowchart showing a schematic process performed in the process of manufacturing the first long optical film F1. Fig. 12 is a flowchart showing a schematic process performed in the process of manufacturing the second long optical film F2. Fig. 13 is a flowchart showing a schematic process performed in the process of manufacturing a long optical laminate.

Fig. 14 is a cross-sectional view schematically showing the state of each film in the process of producing the first long optical film F1 shown in fig. 11. Fig. 15 is a cross-sectional view schematically showing the state of each film in the process of manufacturing the second long optical film F2 shown in fig. 12. Fig. 16 is a cross-sectional view schematically showing the state of each film in the process of manufacturing the long optical laminate shown in fig. 13. Note that the sizes, proportions, and shapes of the constituent elements shown in fig. 14 to 16 may be different from those of actual ones.

The inspection method of the third embodiment includes: as shown in fig. 11, steps S31 to S38 executed in the step of manufacturing the first long optical film F1; as shown in fig. 12, steps S41 to S45 executed in the step of manufacturing the second long optical film F2; as shown in fig. 13, steps S51 to S57 are executed in the step of manufacturing the long optical laminate. Hereinafter, the respective steps will be described in order.

[ Process to be executed in the Process for producing the first Long optical film F1 ]

(Process for producing base Material S31)

In the substrate production step S31 shown in fig. 11, the first long optical film F1 (substrate) shown in fig. 14(a) is produced. The first long optical film F1 is produced by, for example, melt-extruding a resin material to form a resin film and stretching the resin film.

Examples of the resin material for forming the first long optical film F1 include polyesters such as polyethylene terephthalate and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene; cyclic polyolefins such as norbornene polymers; cellulose polymers such as diacetylcellulose and triacetylcellulose; an acrylic polymer; a styrenic polymer; polycarbonates, polyamides, polyimides, and the like. As the resin material, cyclic polyolefin such as norbornene polymer is preferably used.

(first step S32)

In the first step S32, the first inspection apparatus 1 (the imaging unit 1a and the image processing unit 1b) similar to the first embodiment inspects the first long optical film F1 conveyed by the conveying roller in a roll-to-roll manner, and acquires first defect information that is defect information of the first long optical film F1. The acquired first defect information is input to the first arithmetic storage device 4 similar to the first embodiment.

As described later, the first long optical film F1 of the third embodiment as a base material was peeled off and removed after being laminated to the second long optical film F2. However, if there is a defect in the first long optical film, the defect in the first long optical film may be transferred to the liquid crystal layer formed by applying the liquid crystal material to the first long optical film, or the first long optical film may be broken during conveyance, which may cause a trouble in the manufacturing process. Therefore, in the third embodiment, it is also meaningful to inspect the first long optical film F1.

(second step S33)

In the second step S33, the first printing apparatus 2, which is the same as the first embodiment, prints the first identification information M shown in fig. 14(b) by an ink jet method (preferably, an ink jet method using a clear ink) at the end portions of the first long optical film F1 in the width direction at predetermined intervals in the longitudinal direction of the first long optical film F1.

(third step S34)

In the third step S34, the first arithmetic and storage device 34 stores the first defect information of the first long optical film F1 in association with the first identification information M. Specifically, the first arithmetic and storage unit 4 uses the amount of movement of the first long optical film F1 in the transport direction input from the length measuring device 3 to grasp how much the first long optical film F1 has moved in the transport direction between the time when the defect is detected by the first inspection device 1 and the time when the first identification information M is printed by the first printing device 2, and stores at least the first identification information M in association with the coordinates of the defect with reference to the first identification information M.

(coating step S35)

In the coating step S35, a liquid crystal material (liquid crystal composition) is coated on the first long optical film F1, and a liquid crystal layer F11 (oriented liquid crystal layer) shown in fig. 14(c) is formed on the first long optical film F1. As shown in fig. 14(c), the liquid crystal material is applied to the surface of the first long optical film F1 opposite to the surface on which the first identification information M is printed, and an alignment liquid crystal layer F11 is formed on the opposite surface.

The liquid crystal composition applied to the first long optical film F1 contains a liquid crystal compound. After the liquid crystal composition was applied to the first long optical film F1, the liquid crystal compound was aligned in a predetermined direction, and the aligned state was fixed, whereby an aligned liquid crystal layer F11 was formed on the first long optical film F1.

Examples of the liquid crystal compound include rod-like liquid crystal compounds and discotic liquid crystal compounds. Since uniform alignment is easily performed by the alignment control force of the first long optical film F1 (substrate), a rod-like liquid crystal compound is preferably used as the liquid crystal compound. The rod-like liquid crystal compound may be a main chain type liquid crystal or a side chain type liquid crystal. The rod-like liquid crystal compound may be a liquid crystal polymer or a polymer of a polymerizable liquid crystal compound. If the liquid crystal compound (monomer) before polymerization shows liquid crystallinity, it may not show liquid crystallinity after polymerization.

The liquid crystal compound is preferably thermotropic liquid crystal which exhibits liquid crystallinity by heating. Thermotropic liquid crystals undergo phase transition of a crystal phase, a liquid crystal phase, and an isotropic phase with temperature change. The liquid crystal compound contained in the liquid crystal composition may be any of nematic liquid crystal, smectic liquid crystal, and cholesteric liquid crystal. A chiral agent may be added to the nematic liquid crystal to impart cholesteric alignment properties.

When the liquid crystal compound contained in the liquid crystal composition is a thermotropic liquid crystal, the liquid crystal composition is applied to the first long optical film F1, and the liquid crystal compound is aligned in a liquid crystal state by heating to form a liquid crystal composition layer. Then, the liquid crystal composition layer is heated to form a liquid crystal phase, and an aligned liquid crystal layer F11 in which the liquid crystal compound is aligned is formed. The optical properties of the oriented liquid crystal layer F11 are not particularly limited, and functions as, for example, a 1/4 wavelength plate or a 1/2 wavelength plate. Preferably, the aligned liquid crystal layer F11 is a uniformly aligned liquid crystal layer functioning as a 1/4 wavelength plate of the positive a plate.

(reading step S36)

In the reading step S36, in the reading device having the same configuration as the first reading device 9 of the first embodiment, the first identification information M of the first long optical film F1 after the liquid crystal material conveyed by the conveying roller in the roll-to-roll manner is coated (after the oriented liquid crystal layer F11 is formed) is read. The read first identification information M is input to the first arithmetic storage device 4.

(first step (second step) S37)

In the second first step S37, the inspection apparatus having the same configuration as the first inspection apparatus 1 (the image pickup unit 1a and the image processing unit 1b) of the first embodiment inspects the first long optical film F1 after the liquid crystal material conveyed by the conveying roller in a roll-to-roll manner is coated (after the oriented liquid crystal layer F11 is formed), and acquires first' defect information which is defect information of the first long optical film F1 after the liquid crystal material is coated. The acquired first' defect information is input to the first arithmetic storage device 4.

(third step (second step) S38)

In the second third step S38, the first arithmetic and storage unit 4 stores the first' defect information of the first long optical film F1 after the liquid crystal material coating, which was acquired in the second first step S37, in association with the first identification information M read in the reading step S36. In the first arithmetic storage device 4, since the third step S34 stores the first defect information of the first long optical film F1 before the liquid crystal material is applied in association with the first identification information M, the first arithmetic storage device 34 stores the first 'defect information of the first long optical film F1 after the liquid crystal material is applied in association with the first identification information M while covering the first defect information with the first' defect information.

Specifically, the first arithmetic and storage device 4 uses the amount of movement in the transport direction of the first long optical film F1 after the liquid crystal material coating, which is input from the length measuring device having the same configuration as the length measuring device 3, to grasp how much the first long optical film F1 after the liquid crystal material coating has moved in the transport direction between the time when the first identification information M is read by the reading device and the time when the defect is detected by the inspection device (the time when the coordinates of the pixel region corresponding to the defect in the captured image are specified), and stores at least the first identification information M and the coordinates of the defect with the first identification information M as a reference in association with each other.

[ Process to be executed in the Process for producing the second Long optical film F2 ]

(protective film production Process S41)

In the protective film manufacturing step S41 shown in fig. 12, the protective film F21 shown in fig. 15(a) is manufactured. As the protective film F21, the same protective film as the first long optical film F1 of the first embodiment can be used. That is, as the protective film F21, for example, a film made of a polymer such as an acetate-based resin such as triacetyl cellulose, a polycarbonate-based resin, a polyarylate, a polyester-based resin such as polyethylene terephthalate, a polyimide-based resin, a polysulfone-based resin, a polyethersulfone-based resin, a polystyrene-based resin, a polyolefin-based resin such as polyethylene or polypropylene, a polyvinyl alcohol-based resin, a polyvinyl chloride-based resin, a polynorbornene-based resin, (meth) acrylic-based resin, a polymethyl methacrylate-based resin, or a liquid crystal polymer is preferably used.

The protective film F21 can be produced by any of a casting method, a rolling method, and an extrusion method. The manufactured protective film F21 was wound into a roll shape as a roll.

In the third embodiment, unlike the first long optical film F1 of the first embodiment, the protective film F21 is not printed with identification information.

(bonding step S42)

In the step of manufacturing the second long optical film F2, the protective film F21 was wound off a roll, and the polarizing plate F22, which was manufactured separately, was wound off a roll. Then, in the bonding step S42, the protective film F21 is bonded to one side or both sides of the polarizing plate F22 via an adhesive or the like, and as shown in fig. 15(b), a second long optical film F2 (polarizing film) in which the protective film F21 and the polarizing plate F22 are stacked is obtained.

As the polarizing plate F22, the same polarizing plate as the second long optical film of the first embodiment can be used. That is, as the polarizing plate F22, a polarizing plate manufactured by drying a polyvinyl alcohol film subjected to dyeing treatment, crosslinking treatment, and stretching treatment can be used.

(fourth Process S43)

In the fourth step S43, the second inspection apparatus 5 (the image pickup unit 5a and the image processing unit 5b) similar to the first embodiment inspects the second long optical film F2 fed by the feed roller in a roll-to-roll manner, and acquires second defect information that is defect information of the second long optical film F2. The acquired second defect information is input to the second arithmetic storage device 8 similar to the first embodiment.

(fifth step S44)

In the fifth step S44, the second printing device 6, which is the same as the first embodiment, prints the second identification information N shown in fig. 15(c) by laser marking at the end portions of the second long optical film F2 in the width direction at predetermined intervals in the longitudinal direction of the second long optical film F2. Specifically, the second identification information N is printed on the protective film F21 constituting the second long optical film F2.

(sixth Process S45)

In the sixth step S45, the second arithmetic and storage unit 8 stores the first defect information of the second long optical film F2 in association with the second identification information N. Specifically, the second arithmetic and storage device 8 uses the amount of movement of the second long optical film F2 in the transport direction input from the length measuring device 7 to grasp how much the second long optical film F2 has moved in the transport direction between the time when the defect is detected by the second inspection device 5 and the time when the second identification information N is printed by the second printing device 6, and stores at least the second identification information N in association with the coordinates of the defect with reference to the second identification information N.

The first long optical film F1 (a laminate in which the oriented liquid crystal layer F11 is formed on one surface of the first long optical film F1 as a base material and the first identification information M is printed by an ink jet method on the other surface) produced in the first long optical film F1 production process described above is wound in a roll shape as a roll material. The second long optical film F2 (the polarizing film on which the protective film F21 and the polarizing plate F22 are stacked and the second identification information N is printed by laser marking on the protective film F21) produced in the above-described step of producing the second long optical film F2 is wound in a roll shape to be used as a roll. The first long optical film F1 and the second long optical film F2 as rolls are conveyed to a process for manufacturing a long optical laminate. In the step of manufacturing the long optical laminate, the first long optical film F1 and the second long optical film F2 are fed from a roll.

As shown in fig. 13, the process for producing the long optical laminate according to the third embodiment includes the process of No.1 and the process of No. 2. "a" shown in fig. 13 refers to a step after "go to a" shown in fig. 11 and 12.

(bonding step S51)

In the step No.1, the first long optical film F1 (the laminate of the first long optical film F1 and the oriented liquid crystal layer F11) was wound up and the second long optical film F2 (the polarizing film) was wound up. Then, in the laminating step S51, the first long optical film F1 and the second long optical film F2 are laminated via the adhesive 20 (for example, an acrylic adhesive) so that the oriented liquid crystal layer F11 side of the first long optical film F1 faces the polarizing plate F22 side of the second long optical film F2, and as shown in fig. 16(a), a long optical laminate in which the first long optical film F1 and the second long optical film F2 are laminated is obtained. The first identification information M is printed on the first long optical film F1 and the second identification information N is printed on the protective film F21 of the second long optical film F2, respectively, which constitute the long optical laminate.

(seventh Process S52)

In the seventh step S52, the second arithmetic and storage unit 8 stores the first defect information of the first long optical film F1 in association with the second identification information N of the second long optical film F2. Specifically, for a long optical laminate transported by a transport roller in a roll-to-roll manner, first identification information M read by a first reading device 9 and second identification information N read by a second reading device 10 similar to those of the first embodiment are input to a second arithmetic and storage device 8 (in contrast to the embodiment shown in fig. 4, the first reading device 9 can read first identification information M printed on the lowermost surface of the long optical laminate, and the second reading device 10 is disposed so as to read second identification information N printed on the uppermost surface of the long optical laminate). Here, in the second arithmetic storage device 8, similarly to the first embodiment, the association between the first defect information stored in the first long optical film F1 of the first arithmetic storage device 4 and the first identification information M (the relationship between the first identification information M and the coordinates of the defect with reference to the first identification information M) is previously input and stored. Further, the amount of movement of the long optical laminate F2 in the transport direction is input to the second arithmetic and memory device 8 from the length measuring device 11 similar to that of the first embodiment.

The second arithmetic storage device 8 can grasp how much the long optical layered body has moved in the conveying direction between the time when the first identification information M is read by the first reading device 9 (the time when the first identification information M is input to the second arithmetic storage device 8) and the time when the second identification information N is read by the second reading device 10 (the time when the second identification information N is input to the second arithmetic storage device 8) based on the amount of movement of the long optical layered body in the conveying direction input from the length measuring device 11. Based on the amount of movement of the long optical layered body between these two times, the second arithmetic and storage device 8 can calculate the positional displacement of the first identification information M and the second identification information N along the longitudinal direction of the long optical layered body.

Therefore, the second arithmetic and storage device 8 can store the first defect information of the first long optical film F1 and the second identification information N of the second long optical film F2 in association with each other based on the association between the first defect information of the first long optical 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 with reference to the second identification information N. In this way, by executing the seventh step S52, the first defect information and the second defect information can be managed in an integrated manner based on the second identification information N of the second long optical film F2.

(third defect information obtaining step S53)

In the third defect information acquisition step S53, the long optical layered body shown in fig. 16(a) conveyed by the conveying rollers in a roll-to-roll manner is inspected by an inspection apparatus having the same configuration as the second inspection apparatus 5 (the image pickup unit 5a and the image processing unit 5b) of the first embodiment, and third defect information, which is defect information of the long optical layered body, is acquired. The acquired third defect information is input to the second arithmetic storage device 8.

(storing step S54)

In the storing step S54, the second arithmetic and storage unit 8 stores the third defect information of the long optical laminate, which is acquired in the third defect information acquiring step S53, in association with the second identification information N read in the seventh step S52. Specifically, the second arithmetic and storage device 8 uses the amount of movement of the long optical laminate in the transport direction, which is input from a length measuring device having the same configuration as the length measuring device 11, to grasp how much the long optical laminate has moved in the transport direction between the time when the second reading device 10 reads the second identification information N and the time when the defect is detected by the inspection device (the time when the coordinates of the pixel region corresponding to the defect in the captured image are specified), and stores at least the second identification information N and the coordinates of the defect with reference to the second identification information N in association with each other. By executing the storing step S54, the first defect information, the second defect information, and the third defect information can be managed in an integrated manner based on the second identification information N of the second long optical film F2.

The long optical laminate after the storing step S54 is wound into a roll and conveyed to the No.2 step.

(reading step S55)

In the No.2 step, the long optical laminate wound in a roll shape is fed out, and first, the first long optical film F1 (substrate) constituting the long optical laminate shown in fig. 16(a) is peeled off and removed. Then, for example, liquid crystal molecules are aligned perpendicularly (Homeotropic alignment) to the substrate surface (the surface of the first long optical film F1 before peeling and removing) in the aligned liquid crystal layer F11 constituting the long optical laminate through the ultraviolet-curable adhesive 30, thereby forming an aligned liquid crystal layer 40 functioning as a positive C-plate. Further, an adhesive 50 similar to the adhesive 20 is applied to the oriented liquid crystal layer 40. Through the above steps, a long optical laminate shown in fig. 16(b) is formed.

In the long optical laminate shown in fig. 16(b), an oriented liquid crystal layer F11 (preferably, a uniformly oriented liquid crystal layer functioning as a 1/4 wavelength plate as a positive a plate) and an oriented liquid crystal layer 40 functioning as a positive C plate are sequentially laminated on a second long optical film F2 as a polarizing film, and therefore, the long optical laminate can function as a circularly polarized light plate capable of blocking reflected light even with external light from an oblique direction. In the third embodiment, a long optical laminate is manufactured in which the oriented liquid crystal layer F11 and the oriented liquid crystal layer 40 are sequentially laminated on the second long optical film F2 as a polarizing film, but the order may be changed to manufacture a long optical laminate in which the oriented liquid crystal layer 40 and the oriented liquid crystal layer F11 are sequentially laminated on the second long optical film F2. In this case, the oriented liquid crystal layer 40 is formed on the first long optical film F1 (substrate).

In the long optical laminate shown in fig. 16(b), since the first long optical film F1 printed with the first identification information M is peeled off and removed, only the second identification information N printed on the protective film F21 of the second long optical film F2 exists. Then, in the No.2 step, the reading step S55 is performed on the long optical laminate.

In reading step S55, second identification information N is read by second reading device 12, which is the same as the first embodiment. The read second identification information N is input to the second arithmetic storage device 8.

(third Defect information acquisition step (second time) S56)

In the second third defect information obtaining step S56, the second inspection apparatus 13 (the image pickup unit 13a and the image processing unit 13b) similar to the first embodiment inspects the long optical layered body (fig. 16 b) transported by the transport rollers in a roll-to-roll manner, and obtains third defect information which is defect information of the long optical layered body. The acquired third defect information is input to the second arithmetic storage device 8.

(storage step (second time) S57)

In the second storing step S57, the second arithmetic and storage device 8 stores the second defect information of the long optical laminate acquired by the second inspection device 13 in association with the second identification information N read by the second reading device 12. Specifically, the second arithmetic and storage device 8 uses the amount of movement of the long optical laminate in the transport direction input from the length measuring device 14 similar to that in the first embodiment, to grasp how much the long optical laminate has moved in the transport direction between the time when the second reading device 12 reads the second identification information N and the time when the defect is detected by the second inspection device 13 (the time when the coordinates of the pixel region corresponding to the defect in the captured image are specified), and stores at least the second identification information N and the coordinates of the defect with reference to the second identification information N in association with each other.

In the inspection method according to the third embodiment described above, the first identification information M is printed by an ink jet method and the second identification information N is printed by laser scribing (however, the present invention is not limited thereto, and the first identification information M and the second identification information N may be printed in any one of the above-described print patterns one to six). Therefore, according to the inspection method of the third embodiment, as in the first embodiment, even if the first identification information M and the second identification information N overlap each other when viewed in the vertical direction, both can be read separately. That is, it is possible to appropriately associate the defect information with the identification information (associate the first defect information with the first identification information M (and further the second identification information N), associate the second defect information with the second identification information N, and associate the third defect information with the second identification information N).

Further, for example, by reading the second identification information N, using the association between the second defect information and the second identification information N stored in the sixth step S45, using the association between the first defect information and the second identification information N stored in the seventh step S52, and using the association between the third defect information and the second identification information N stored in the storing steps S54 and S57, it is possible to punch out a product while avoiding the position of a defect generated in the state of the first long optical film F1, the position of a defect generated in the state of the second long optical film F2, and the position of a defect generated in the state of the long optical laminate.

In the third embodiment, the case where the first long optical film F1 on which the first identification information M is printed is a substrate to which a liquid crystal material is applied (substrate on which the oriented liquid crystal layer F11 is formed), and the oriented liquid crystal layer F11 functions as a 1/4 wavelength plate has been described as an example, but the invention is not limited thereto. As the first long optical film F1, a stretched film (retardation film) using a resin film that functions as a 1/4 wavelength plate may be used, and the first identification information M may be printed on the stretched film (in this case, the first long optical film F1 is not peeled off and removed after being bonded to the second long optical film F2). Examples of the material of such a resin film include a polycarbonate-based resin, a polyester-carbonate-based resin, a polyester-based resin, a polyvinyl acetal resin, a polyarylate-based resin, a cycloolefin-based resin, a cellulose-based resin, a polyvinyl alcohol-based resin, a polyamide-based resin, a polyimide-based resin, a polyether-based resin, a polystyrene-based resin, and an acrylic resin. These resins may be used alone or in combination (for example, by blending or copolymerizing).

< fourth embodiment >

The method for inspecting a long optical laminate according to a fourth embodiment of the present invention is a combination of the method for inspecting a first embodiment and the method for inspecting a third embodiment, or a combination of the method for inspecting a second embodiment and the method for inspecting a third embodiment.

Specifically, in the inspection method of the fourth embodiment, the identification information is printed on the protective film, as in the inspection methods of the first and second embodiments, the identification information is printed on the polarizing film (laminated body of the protective film and the polarizing plate), as in the inspection methods of the first to third embodiments, and the identification information is printed on the base material or the phase difference film, as in the inspection method of the third embodiment.

Fig. 17 is an explanatory view for explaining a print pattern in the inspection method for a long optical laminate according to the fourth embodiment. Fig. 17(a) is a cross-sectional view schematically showing the state of a long optical laminate corresponding to the long optical laminate obtained in the bonding step S51 of the third embodiment (the long optical laminate before the substrate F1 shown in fig. 16(a) is peeled off). Fig. 17(a) shows a preferred print pattern in the fourth embodiment.

As shown in fig. 17(a), the identification information printed on the base material F1 (or the phase difference film) is set as first identification information M, the identification information printed on the polarizing film F2 (specifically, the protective film F21) is set as second identification information N, and the identification information printed on the protective film F21 is set as third identification information P. In this case, according to the findings of the present inventors, it is preferable that the first identification information M, the second identification information N, and the third identification information P be printed in any one of the first to sixth print patterns shown in fig. 17 (b). That is, it is preferable that only one identification information is printed by laser engraving and only one identification information is printed by an ink jet method using a colored ink among the first identification information M, the second identification information N, and the third identification information P. By printing the first identification information M, the second identification information N, and the third identification information P in any one of the first to sixth print patterns shown in fig. 17(b), even if the first identification information M, the second identification information N, and the third identification information P overlap each other when viewed in the vertical direction, they can be read separately. That is, the defect information can be appropriately associated with the identification information.

Description of the reference numerals

1 first inspection device

2 first printing device

3. 7, 11, 14 length measuring device

4 first operation 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 first strip optical film

F2 long optical laminate and second long optical film

M first identification information

N second identification information

Claims

1. A method of inspecting an elongated optical laminate, comprising: a first step of inspecting a first long optical film to acquire first defect information that is defect information of the first long optical film;

a second step of printing first identification information on the end portion of the first long optical film in the width direction at predetermined intervals in the longitudinal direction of the first long optical film;

a third step of storing the first defect information of the first long optical film in association with the first identification information;

a fourth step of inspecting a second long optical film or a long optical laminate in which the first long optical film and the second long optical film are laminated, and acquiring second defect information that is defect information of the second long optical film or the long optical laminate;

a fifth step of printing second identification information on the end portions of the second long optical film or the long optical laminate in the width direction at predetermined intervals in the longitudinal direction of the second long optical film or the long optical laminate;

a sixth step of storing the second defect information of the second long optical film or the long optical laminate in association with the second identification information;

the first identification information printed in the second step and the second identification information printed in the fifth step may be printed in an inkjet method and the other may be printed in a laser scribe method, or the first identification information and the second identification information may be printed in an inkjet method using a transparent ink and the other may be printed in an inkjet method using a colored ink.

2. The method of inspecting a long optical laminate according to claim 1, wherein in the second step, the first identification information is printed by an ink-jet method using a transparent ink,

in the fifth step, the second identification information is printed by laser imprint.

3. The method for inspecting an elongated optical laminate according to claim 1 or 2, further comprising a seventh step of storing the first defect information of the first elongated optical film in association with the second identification information of the second elongated optical film or the elongated optical laminate.

4. The method for inspecting an elongated optical laminate according to any one of claims 1 to 3, further comprising an eighth step of marking a position of a defect in the elongated optical laminate on the basis of the first identification information and the first defect information of the first elongated optical film and the second identification information and the second defect information of the second elongated optical film or the elongated optical laminate.

5. The method for inspecting an elongate optical laminate according to any one of claims 1 to 4, wherein the first elongate optical film is a protective film,

the second long optical film is a polarizing plate,

the long optical laminated body is a polarizing film.

6. The method for inspecting an elongate optical laminate according to any one of claims 1 to 4, wherein the first elongate optical film is a retardation film or a substrate coated with a liquid crystal material,

the second long optical film is a polarizing film.

7. The method for inspecting an elongate optical laminate according to any one of claims 1 to 4, wherein the first elongate optical film is a reflective polarizing plate,

the second long optical film is a polarizing film.

8. The method for inspecting an elongated optical laminate according to claim 5, wherein a knurled portion is formed at an end portion in a width direction of the first elongated optical film,

in the second step, the first identification information is printed by ink jet on the first long optical film at a portion corresponding to the knurled portion.

9. The method for inspecting an elongated optical laminate according to claim 5, wherein a knurled portion is formed at an end portion in a width direction of the first elongated optical film,

in the fifth step, the second identification information is printed on a portion of the long optical film or the long optical laminate located on the inner side in the width direction than the knurled portion of the first long optical film.

10. A method for inspecting a long optical laminate, comprising: a first inspection device that inspects a first long optical film to acquire first defect information that is defect information of the first long optical film;

a second printing device that prints first identification information at the end of the first long optical film in the width direction at predetermined intervals in the longitudinal direction of the first long optical film;

a first arithmetic storage device that stores the first defect information of the first long optical film in association with the first identification information;

a second inspection device that inspects a second long optical film or an optical laminate having the first long optical film and the second long optical film laminated thereon, and acquires second defect information that is defect information of the second long optical film or the long optical laminate;

a second printing device that prints second identification information at predetermined intervals in a longitudinal direction of the second long optical film or the long optical laminate at ends in the width direction of the second long optical film or the long optical laminate;

a second calculation and storage device that stores the second defect information of the second long optical film or the long optical laminate in association with the second identification information;

the first identification information printed by the first printing device and the second identification information printed by the second printing device may be printed by an inkjet method and the other by laser marking, or the first identification information and the second identification information may be printed by an inkjet method using a clear ink and the other by an inkjet method using a colored ink.