Method and apparatus for manufacturing optical film

Abstract

The present invention provides a method and apparatus for manufacturing an optical film, which can cut an optical film having a non-optical functional portion locally from a longitudinal raw material film. Even when the difference in brightness between the non-optical functional portion and the optical functional portion is small, an optical film having the non-optical functional portion arranged with good precision can be manufactured. The method for manufacturing an optical film according to an embodiment of the present invention comprises: cutting a longitudinal strip of film having a detection portion; when cutting the strip of film, detecting the position of the detection portion, positioning the cutting line based on the detected position of the detection portion, and obtaining an optical film as a film sheet having the detected detection portion piece by piece. The strip of film comprises an anti-glare layer having a haze of 5.0% or more; the detection portion is a non-anti-glare portion formed locally on the anti-glare layer and having a haze of less than 1.0%; in the above-mentioned manufacturing method, an illumination component and a camera that irradiates red light are used to detect the position of the detection portion.

Description

Technical Field

[0001] The present invention relates to a method and apparatus for manufacturing an optical film. Background Art

[0002] Among image display devices such as mobile phones and notebook personal computers (PCs), there are image display devices equipped with internal electronic components such as cameras. In such image display devices, in many cases, an optical film with a non-optical functional portion formed locally is used. As such optical films, for example, a polarizer with a non-polarizing portion formed locally and an anti-glare film with a non-anti-glare portion formed locally can be cited. Optical films can usually be produced by cutting a raw film roll into film sheets of a specified size (a size corresponding to the image display device to which it is applied). In order to improve the position accuracy (and, as a result, the cutting accuracy) when cutting the optical film, an alignment mark is sometimes provided. In addition, for polarizers with a non-polarizing portion formed locally, a technology for using the non-polarizing portion as an alignment mark has been proposed (for example, Patent Document 1). In the technology of Patent Document 1, in most cases, the single transmittance of the polarizer (the polarizing portion) is 45% or less, and the transmittance of the non-polarizing portion is 90% or more. Therefore, the difference in brightness (brightness) between the polarizing portion and the non-polarizing portion is large, and the boundary is clear. On the other hand, for anti-glare films with partially formed non-anti-glare areas, the difference in brightness (luminance) between the anti-glare and non-anti-glare areas is not as great as that of the polarizing plate, so the non-anti-glare areas may not be used as alignment marks.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 6146921 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] The present invention is made to solve the above-mentioned previous problems, and its main purpose is to provide a method for manufacturing an optical film, in which an optical film having a non-optical functional portion locally is cut from a longitudinal raw material film, wherein even when the difference in brightness between the non-optical functional portion and the optical functional portion is small, an optical film with a non-optical functional portion configured with good precision can be manufactured.

[0008] Solutions for solving problems

[0009] [1] According to one embodiment of the present invention, a method for manufacturing an optical film is provided. The manufacturing method comprises: cutting a longitudinal strip of film having a detection portion; when cutting the strip of film, detecting the position of the detection portion, positioning the cutting line based on the detected position of the detection portion, and obtaining an optical film as a film sheet having the detected detection portion piece by piece. In an embodiment of the present invention, the strip of film comprises an anti-glare layer having a haze of 5.0% or more; the detection portion is a non-anti-glare portion having a haze of less than 1.0% formed locally on the anti-glare layer; and the manufacturing method uses an illumination component that irradiates red light and a camera to detect the position of the detection portion.

[0010] [2] In the above [1], the lighting component is annular, and the manufacturing method includes using the lighting component to illuminate the detection portion.

[0011] [3] In the above-mentioned [2], the annular lighting component has LEDs emitting red light arranged in an annular frame of a predetermined width, and the annular lighting component is configured such that the frame is inclined radially outward and the individual LEDs are inclined radially inward.

[0012] [4] In any one of the above [1] to [3], the manufacturing method includes: before cutting the strip film in the width direction, detecting the single-side end edge of the strip film in the width direction; when cutting the strip film, moving the cutting component from one side to the other side in the width direction of the strip film, and determining the moving direction of the cutting component based on the detected single-side end edge.

[0013] [5] According to another embodiment of the present invention, a manufacturing device for an optical film is provided. The manufacturing device includes: a conveying component that conveys a strip of film at a predetermined lengthwise feeding pitch; a detecting component that includes an illuminating component that irradiates a detected portion of the strip of film with red light and a photographing device that photographs the irradiated detected portion, wherein the detecting component detects the detected portion; and a cutting component that moves from one side to the other side in the width direction of the strip of film and positions a cutting line based on the position of the detected detected portion. In an embodiment of the present invention, the strip of film includes an anti-glare layer having a haze of 5.0% or more, and the detected portion is a non-anti-glare portion formed locally on the anti-glare layer and having a haze of less than 1.0%.

[0014] [6] In the above [5], the above-mentioned lighting component is ring-shaped.

[0015] [7] In the above [6], the annular lighting component has LEDs emitting red light arranged in an annular frame of a predetermined width, and the annular lighting component is configured such that the frame is inclined radially outward and the individual LEDs are inclined radially inward.

[0016] Effects of the Invention

[0017] According to an embodiment of the present invention, in a method for manufacturing an optical film in which an optical film partially having a non-optical functional portion is cut from a longitudinal raw material film, a method can be realized in which an optical film having a non-optical functional portion configured with good precision can be manufactured even when the difference in brightness between the non-optical functional portion and the optical functional portion is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic plan view of a strip-shaped film that can be used in the production method according to the embodiment of the present invention.

[0019] Figure 2 yes Figure 1 A schematic cross-sectional view of a strip-shaped film along line II-II.

[0020] Figure 3 (a) Figure 3 (a') and Figure 3 (b)~ Figure 3 (d) is a schematic diagram showing a method for producing an optical film according to one embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram illustrating an imaging device and lighting components that can be used in the manufacturing method according to the embodiment of the present invention.

[0022] Figure 5 (a)~ Figure 5 (c) is a schematic plan view illustrating an example of an arrangement pattern of detection portions of a strip-shaped film that can be used in the embodiment of the present invention.

[0023] Description of Reference Numerals

[0024] 10. Anti-reflection layer; 20. Anti-glare layer; 21. Anti-glare portion; 22. Detected portion (non-anti-glare portion); 25. Cutting line; 30. Detection component; 32. Camera; 34. Red lighting component; 50. Cutting component; 60. Optical film (film sheet); 100. Strip film. DETAILED DESCRIPTION

[0025] Hereinafter, representative embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to these embodiments. In addition, in order to facilitate observation and understanding, the drawings are schematically or conceptually depicted, and the length, width, shape, size, ratio, direction, number, etc. may be different from the actual ones. Figure 1 and Figure 3 ) does not correspond.

[0026] A. Overview of the Method for Manufacturing an Optical Film

[0027] The method for manufacturing an optical film according to an embodiment of the present invention includes: cutting a longitudinal strip of film having a detection portion; detecting the position of the detection portion when cutting the strip of film, positioning the cutting line based on the detected position of the detection portion, and obtaining the optical film as a film sheet having the detected detection portion, sheet by sheet. In an embodiment of the present invention, the strip of film includes an anti-glare layer having a haze of 5.0% or greater; the detection portion is a non-anti-glare portion formed locally on the anti-glare layer and having a haze of less than 1.0%; and the manufacturing method uses an illumination component that irradiates red light and a camera to detect the position of the detection portion. Below, after describing the strip of film used in the manufacturing method, the manufacturing method will be described in detail.

[0028] B. Strip film

[0029] Figure 1 is a schematic top view of a strip-shaped film that can be used in the manufacturing method according to an embodiment of the present invention. Figure 2 yes Figure 1 Schematic cross-sectional view of a strip film based on line II-II. The strip film is longitudinally long and typically can be transported in a roll. The strip film has a detection portion. The strip film 100 shown in the figure has a longitudinally long anti-reflection layer 10 and an anti-glare layer 20 formed on the anti-reflection layer 10. The anti-glare layer 20 typically has: an anti-glare portion 21, which occupies most of the anti-glare layer and has an anti-glare function; and a non-anti-glare portion 22, which is formed at a predetermined position. In the embodiment of the present invention, as described above, the non-anti-glare portion 22 is the detection portion.

[0030] The anti-glare layer 20 is typically formed at predetermined intervals in the length direction and width direction of the anti-reflection layer 10. In one embodiment, the anti-glare layer is formed into a shape corresponding to the shape of an image display device to which the strip-shaped film is cut into an optical film (film sheet) for application. In other words, the anti-glare layer may have a shape corresponding to the shape of the optical film (film sheet) to be finally used. The anti-glare layer of the illustrated example has a rectangular shape defined by a pair of sides that are respectively opposite in the length direction and width direction of the anti-reflection layer. The non-anti-glare portion 22 is typically formed at a position corresponding to the camera portion of the image display device when the strip-shaped film is cut into a film sheet in order to mount the strip-shaped film on the image display device.

[0031] The haze of the antireflection layer is less than 1.0%, preferably 0.8% or less, more preferably 0.5% or less, and even more preferably 0.3% or less. The lower the haze, the better, and the lower limit of the haze can be, for example, 0.1%. If the haze of the antireflection layer is within this range, when the optical laminate (film sheet) is ultimately used in an image display device, it can provide an antireflection function without adversely affecting display performance.

[0032] The anti-reflection layer has the desired anti-reflection properties and can adopt any appropriate structure as long as it satisfies the haze as described above. Specifically, the anti-reflection layer can be a cured layer of a curable resin composition or a layer formed by a dry process. The curable resin composition typically contains a binder resin and, if necessary, a photopolymerization initiator. The binder resin typically contains a curable compound. As the curable compound, for example, a multifunctional monomer, an oligomer or a prepolymer derived from the multifunctional monomer can be listed. As the layer formed by the dry process, for example, a WET coating layer, a sputtering layer or a vapor deposition treatment layer of a low refractive index material can be listed.

[0033] The haze of the anti-glare portion of the anti-glare layer is 5.0% or more, preferably 15% to 55%, more preferably 25% to 45%, and further preferably 30% to 40%. If the haze of the anti-glare layer is within this range, it can impart a good anti-glare function when the optical laminate (film sheet) is ultimately applied to an image display device. The haze of the non-anti-glare portion can typically be the same as the haze of the anti-reflection layer. The haze of the non-anti-glare portion is, for example, less than 1.0%, preferably less than 0.8%, more preferably less than 0.5%, and further preferably less than 0.3%. The lower the haze, the better, and the lower limit of the haze can be, for example, 0.1%. The haze difference between the anti-glare portion 21 and the non-anti-glare portion 22 is, for example, greater than 4% and less than 50%, and can be, for example, 25% to 45%. In this way, the haze difference between the detected portion (non-anti-glare portion 22) and the other portion (anti-glare portion 21) of the strip film that can be used in the embodiment of the present invention is at least about 4%. On the other hand, in conventional techniques, even if the non-anti-glare portion is intended to be used as a detection portion (alignment mark), the difference in brightness (luminance) between the detection portion and the remaining portion is insufficient, and the boundary between the detection portion and the remaining portion may be difficult to discern. According to an embodiment of the present invention, even with such a strip-shaped film, the non-anti-glare portion can be effectively used as a detection portion (alignment mark).

[0034] The anti-glare layer has a desired anti-glare function (antiglare function), and any appropriate structure can be adopted as long as the haze as described above is satisfied. Specifically, the anti-glare layer can be formed by a curable resin composition comprising a binder resin and particles. The curable resin composition is the same as the anti-reflection layer in terms of including particles. The details of the anti-glare layer are described in, for example, Japanese Patent Application Publication No. 2021-139981. The records of the publication are incorporated into this specification as a reference.

[0035] In one embodiment, the anti-glare layer is formed directly on the anti-reflection layer. For example, the anti-glare layer can be formed by applying the curable resin composition through a mask having a predetermined pattern and curing the applied film.

[0036] Typically, the strip film is cut into an optical film (film sheet) for use in an image display device, as described above. Typically, the area of ​​the anti-glare layer, located a predetermined distance inward from the outer edge, is cut. This cut imparts an anti-glare function to the entire final optical film (film sheet) (excluding the non-anti-glare portion).

[0037] Optical films are typically laminated to polarizing plates to serve as polarizing plates with functional layers. The polarizer of a polarizing plate typically has a non-polarizing portion. The non-polarizing portion is typically formed at a location corresponding to the non-anti-glare portion. The optical film and polarizing plate are typically laminated after being cut into separate film sheets. In a polarizing plate with functional layers, the non-anti-glare portion and the non-polarizing portion are formed at locations corresponding to the camera portion of an image display device. This structure can impart desired characteristics to an image display device while minimizing any adverse effects on camera performance.

[0038] C. Details of the manufacturing method

[0039] Figure 3 (a) Figure 3 (a') and Figure 3 (b)~ Figure 3 (d) is a schematic diagram showing a method for manufacturing an optical film according to an embodiment of the present invention. The manufacturing method according to the embodiment of the present invention comprises: sequentially cutting a strip of film 100 having two or more detection portions (non-anti-glare portions) 22 in the width direction and two or more detection portions (non-anti-glare portions) 22 in the length direction from one side of the strip of film 100 to the other side according to each predetermined longitudinal feed pitch; when cutting the strip of film 100, detecting the position of the detection portion 22 ( Figure 3 (a)), the cutting line is positioned based on the position of the detected portion 22 ( Figure 3 (b)), the film sheet 60 having the detected portion 22 is obtained one by one. In addition, as described above, the film sheet 60 may have a shape corresponding to the shape of the anti-glare layer 20 (anti-glare portion 21).

[0040] Therefore, the manufacturing apparatus used in this manufacturing method includes: a conveying unit that conveys a strip of film at a predetermined longitudinal feed pitch (hereinafter referred to as simply the feed pitch); a detecting unit that detects a detected portion of the strip of film; and a cutting unit. Preferably, the cutting unit moves from one side to the other side in the width direction of the strip of film and positions the cutting line based on the detected position of the detected portion. Figure 3(a') is a schematic cross-sectional view showing an example of a detection component and a cutting component. In this example, a rectangular cutting knife (such as a Thomson knife) is used as the cutting component 50. In an embodiment of the present invention, as shown in FIG. Figure 4 As shown, as the detection unit 30, a shooting device (camera) 32 and an illumination unit 34 for irradiating red light are used in combination. Figure 3 As shown, the detection component 30 and the cutting component 50 are integrally formed and are arranged to be movable along the track 40. In another embodiment, the detection component and the cutting component are independently arranged, the detection component is fixed so as to be able to illuminate and photograph a predetermined area of ​​the strip film to detect the detected portion, and the cutting component is arranged to be movable. Figure 4 In the illustrated embodiment, the imaging device 32 and the lighting unit 34 are integrally configured, but they may be provided independently.

[0041] In the embodiment of the present invention, as described above, the strip film 100 having two or more detection portions 22 in the width direction and two or more detection portions 22 in the length direction is fed from one side of the strip film 100 to the other side in the width direction at each feeding pitch. Figure 3 In the example shown, the film sheets 60 having the detection portion 22 are cut sequentially (from the left side of the drawing to the right side) to obtain each sheet. In this specification, the longitudinal direction refers to a direction that corresponds to the conveyance direction Y of the strip-shaped film. However, this direction is not necessarily parallel to the conveyance direction Y but also includes directions that are greater than -45° and less than 45° relative to the conveyance direction Y. Furthermore, the width direction refers to a direction that is between -45° and 45° relative to the direction X that is perpendicular to the conveyance direction Y.

[0042] In the film sheet 60, the detected portion 22 is a non-anti-glare portion as described above. In other words, in an embodiment of the present invention, the non-anti-glare portion is used as the detected portion, and the cutting line is determined based on the non-anti-glare portion. According to an embodiment of the present invention, the cutting position is determined based on the position of the detected portion, so that a film sheet with a well-precise positioning of the detected portion (non-anti-glare portion) can be obtained. In addition, even in the case where there is a deviation in the intervals between the detected portions on the strip film, or in the case where the strip film is winding, a film sheet with a well-precise positioning of the detected portion can be obtained. And, as described in detail later, by combining the camera 32 and the specific red lighting component 34 and detecting the detected portion (non-anti-glare portion) 22 ( Figure 4 ), even when the difference in brightness (luminance) between the detected portion (non-anti-glare portion) and other portions (anti-glare portion) is small, the boundary can be well identified, thereby enabling the detected portion (non-anti-glare portion) to be well detected.

[0043] Figure 5 (a) is a schematic plan view illustrating an example of a configuration pattern of the detection portion 22 of the strip-shaped film 100. Figure 5 (b) is a schematic plan view illustrating another example of the configuration pattern of the detection portion 22. Figure 5 (c) is a schematic top view illustrating another example of the configuration pattern of the detection portion 22. The detection portion 22 can be configured in any appropriate manner depending on the purpose of the optical film (film sheet), etc. The detection portion 22 is preferably configured on a substantially straight line in the width direction ( Figure 5 (a)). In addition, the arrangement direction of the detection portion 22 can be any appropriate angle relative to the width direction end of the strip film 100. That is, the arrangement direction of the detection portion can be orthogonal to the direction of the width direction end of the strip film 100 ( Figure 5 (a)), or non-orthogonal ( Figure 5 (b)). In addition, the intervals between the detection parts 22 in the width direction and the length direction can be the same ( Figure 5 (a)), or different ( Figure 5 (c)). According to the embodiment of the present invention, it is possible to obtain an optical film (film sheet) in which the detection portion is positioned with good accuracy corresponding to the configuration pattern of various detection portions. In addition, even if Figure 5 Even with an irregular arrangement pattern as shown in (c), an optical film (film sheet) in which the detection portion is positioned with high precision can be obtained.

[0044] When cutting the strip film 100, Figure 3 The position of the detected portion 22 is detected as shown in (a), and then, as shown in Figure 3As shown in (b), the positioning of the cutting line 25 is performed based on the position of the detected portion 22. In one embodiment, the positioning of the cutting line 25 can be performed as follows: based on the position of the detected portion 22, the position of a specific portion in the shape specified by the cutting line 25 and the orientation of the planar shape specified by the cutting line 25 are controlled. The specific portion in the shape specified by the cutting line 25 can be any portion of the shape, for example, the center of gravity, the vertex, a point on the edge of the shape, etc. can be listed. In another embodiment, similar to the case of detecting the detected portion (non-anti-glare portion) 22 (described later), the detection component 30 can be used to detect the end of the anti-glare layer 20 (anti-glare portion 21) to perform positioning of the cutting line 25. After the positioning of the cutting line 25 is performed, the strip film 100 is cut to obtain the optical film (film sheet) 60 having the detected portion 22 one by one. The shape of the optical film (film sheet) 60 can be any appropriate shape. For example, rectangle, square, polygon, circle, ellipse and the like can be cited. The shape of the optical film (film sheet) 60 is typically a shape corresponding to the shape of the image display device to which the optical film (film sheet) is applied, as described above. In one embodiment, as the optical film (film sheet) 60, an area inside the anti-glare layer 20 at a predetermined distance from the outer edge can be cut. Therefore, the shape of the optical film (film sheet) 60 can be a shape similar to the shape of the anti-glare layer of the strip film. In addition, for easy observation, Figure 3 In (a), (b), (c), and (d), description of the anti-glare layer 20 is omitted except for a part.

[0045] In an embodiment of the present invention, Figure 4 As shown, the detection part 30 having a camera 32 and a specific red lighting part 34 is used to detect the detected part (non-anti-glare part) 22. Specifically, the lighting part 34 is used for illumination, and the reflected light of the non-anti-glare part 22 is detected by the camera 32. The detailed steps of the detection are as follows: (i) setting an area for detecting the boundary of the brightness and darkness (contrast) of the lighting part within the field of view of the camera; (ii) setting the number of detection points, and calculating the contour shape of the circle by the least square method based on the edge information of many detected points; (iii) forming an approximate circle relative to the contour of the circle, and calculating the center position and diameter (or radius) of the circle. The lighting part 34 is preferably annular as shown in the example. By using an annular lighting part, the contour of the non-anti-glare part can be better detected than a linear (rod-shaped) lighting part. The annular lighting part 34 is typically an annular frame (annular when viewed from above) with LEDs arranged therein. Depending on the type of LED, the wavelength of the irradiated red light can be changed. The annular lighting part 34 is preferably as follows. Figure 4As shown, the frame is configured to be tilted toward the radial outside (tilted downward in the example shown). As a result, each LED is configured to be tilted toward the radial inside (tilted downward in the example shown). If it is such a structure, the irradiated light can be more concentrated on the non-anti-glare part, and as a result, the measurement deviation can be reduced. The irradiation angle is preferably 85° to 95° based on the irradiation surface (anti-glare layer surface, horizontal plane), and more preferably about 90°. The color of the light irradiated from the lighting component 34 is red as mentioned above. Although it is not clear in theory, by irradiating red light, even in the case where the difference in haze (resulting in brightness, luminance) is small, such as between the non-anti-glare part and the anti-glare part, the boundary can be well identified and the detected part (non-anti-glare part) can be well detected. In addition, the deviation of the detection accuracy can be reduced. The wavelength of the red light is preferably 620nm to 750nm, and more preferably 630nm to 640nm. If the wavelength of the red light is in such a range, the above-mentioned effect based on the red light can be made more significant. The red light is preferably light with a sharp wavelength distribution. For example, the half-value width of red light is preferably 15nm to 30nm, more preferably 15nm to 20nm. If the half-value width is within this range, the aforementioned effect of red light can be more pronounced, similar to the case of controlling the wavelength. Furthermore, in the illustrated example, the detection component 30 is positioned above the strip-shaped film, but it can also be positioned below. Alternatively, one of the imaging device 32 and the lighting component 34 can be positioned above, while the other can be positioned below.

[0046] The detection of the detected portion (non-anti-glare portion) 22 by the detection component 30 can typically be performed based on brightness (luminance), transmittance, hue, or a combination thereof. According to an embodiment of the present invention, even when the difference in brightness (luminance) and the difference in optical properties between the detected portion (non-anti-glare portion) and other portions (anti-glare portion) is small, the boundary can be well identified, and the detected portion (non-anti-glare portion) can be well detected.

[0047] As a cutting member when cutting the strip-shaped film 100, any appropriate member can be adopted. Figure 3As shown, a strip of film 100 is cut using a punching blade 50 corresponding to the shape of an optical film (film sheet) 60. For example, when a punching blade 50 such as a Thomson knife is used as the cutting member, positioning of the cutting line 25 is performed by detecting the position of the detected portion 22. Based on the detected position of the detected portion 22, the position of a specific portion of the planar shape defined by the punching blade 50 (e.g., the center of gravity, a vertex, a point on an edge of the shape), as well as the orientation of the planar shape defined by the punching blade 50 (i.e., the angle relative to the conveying direction Y and the direction orthogonal to the conveying direction X) are controlled. After positioning the cutting line 25, the punching blade 50 is moved upward or downward toward the strip of film 100 to punch out the strip of film 100, thereby obtaining the optical film (film sheet) 60.

[0048] Another example of the cut member is cutting by laser irradiation, cutting by a drill, router processing, water jet processing, and the like.

[0049] In one embodiment, when the strip film 100 is cut in the width direction, the cutting member 50 is moved from one side to the other side in the width direction of the strip film 100. By the above operation, after cutting one film sheet, the cutting member is moved in the width direction, and the next film sheet is cut by the same operation as the above operation ( Figure 3 (b)~ Figure 3 (d)). The movement of the cutting member 50 is preferably linear. The movement direction of the cutting member 50 can be set to any appropriate direction depending on the configuration of the detection unit 22. The movement direction of the cutting member 50 is preferably 90°±45°, more preferably 90°±30°, and even more preferably 90°±15° relative to the direction of the one-side end edge in the width direction of the strip-shaped film 100.

[0050] In one embodiment, before the strip film 100 is cut in the width direction, one end side of the strip film 100 is detected, and the movement direction of the cutting member 50 is determined based on the detected end side (more specifically, the direction of the detected end side). By determining the movement direction of the cutting member based on the end side of the strip film in the width direction, an optical film (film sheet) can be obtained in which the detection portion (i.e., the functional portion) is accurately positioned, even when the strip film is meandering.

[0051] When detecting one end edge in the width direction of the strip-shaped film 100, a detection member that detects the detected portion 22 may be used, or a detection member provided separately from the detection member that detects the detected portion 22 may be used. In other words, the manufacturing apparatus according to the embodiment of the present invention may include one or more detection members.

[0052] After the strip film 100 is cut from one row in the width direction, the strip film 100 is fed by a predetermined feed pitch, and the next row is cut from one row in the width direction. Cutting one row in the width direction and feeding the strip film 100 by one pitch after this operation constitute one cycle. By repeating this cycle a predetermined number of times, a plurality of optical films (film sheets) 60 can be obtained from the longitudinal strip film (raw material film) 100. The feed pitch can be set based on the longitudinal spacing of the detection sections 22. For example, when the detection sections are arranged in the longitudinal direction parallel to the feed direction Y, the feed pitch is preferably the same as the longitudinal spacing of the detection sections 22.

[0053] [Example]

[0054] Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples.

[0055] <Example 1>

[0056] A long, strip-shaped film having an anti-glare portion and a non-anti-glare portion was prepared. The haze of the anti-glare layer (anti-glare portion) was 25%, and the haze of the anti-reflection layer and the non-anti-glare portion was 0.1%. Using a ring-shaped lighting component, the non-anti-glare portion of the strip-shaped film was irradiated with red light of a wavelength of 635 nm at an irradiation angle of 90°, and the reflected light was captured using a camera. The result was a high-contrast image, allowing the boundary between the non-anti-glare portion and the anti-glare portion to be clearly identified.

[0057] Comparative Example 1

[0058] The non-anti-glare portion of the strip-shaped film was illuminated in the same manner as in Example 1, except that the light emitted by the illumination component was blue light with a wavelength of 470 nm. The reflected light was captured using a camera. The resulting image had low contrast, and the boundary between the non-anti-glare portion and the anti-glare portion could not be clearly identified.

[0059] Comparative Example 2

[0060] The same procedure as in Example 1 was used, except that the light emitted by the lighting component was white light. The non-anti-glare portion of the strip-shaped film was illuminated, and the reflected light was captured with a camera. As a result, the contrast of the captured image was low, and the boundary between the non-anti-glare portion and the anti-glare portion could not be clearly identified.

[0061] Reference Example 1

[0062] A polarizing plate having a polarizer (thickness 5 μm) and a protective layer located on one side of the polarizer was prepared by conventional methods. The surface of the polarizer of the polarizer was treated with sodium hydroxide through a mask to form a non-polarizing portion on the polarizer. The single transmittance of the polarizer was 43%, and the transmittance of the non-polarizing portion was 95%. In addition to using the polarizing plate, the non-polarizing portion was irradiated in the same manner as in Example 1, and its reflected light was photographed using a camera. As a result, the contrast of the captured image was high, and the boundary between the non-polarizing portion and the other parts could be clearly identified.

[0063] Reference Example 2

[0064] The same procedure as in Reference Example 1 was used, except that the illumination component was set to blue light with a wavelength of 470 nm. The non-polarized portion was illuminated and the reflected light was captured with a camera. The resulting image had high contrast, and the boundary between the non-polarized portion and the remaining portion was clearly discernible.

[0065] Reference Example 3

[0066] The same procedure as in Reference Example 1 was used, except that the light emitted by the illumination component was white light. The non-polarized portion was illuminated and the reflected light was captured by a camera. The resulting image had high contrast, and the boundary between the non-polarized portion and the remaining portion could be clearly identified.

[0067] Comparison of Example 1 with Comparative Examples 1 and 2 demonstrates that irradiating the non-anti-glare portion with red light allows for better identification of the boundary between the non-anti-glare portion and the anti-glare portion, enabling better detection of the non-anti-glare portion. Furthermore, Reference Examples 1 to 3 demonstrate that this effect is unique to a strip-shaped film comprising an anti-reflection layer and an anti-glare layer partially formed with a non-anti-glare portion.

[0068] Industrial applicability

[0069] For example, the manufacturing method of an embodiment of the present invention can be preferably used when manufacturing an optical laminate (e.g., a polarizing plate with a functional layer) for use in mobile phones such as smartphones, notebook PCs, tablet computers, and other image display devices with cameras (liquid crystal display devices, organic EL devices).

Claims

1. A method for manufacturing an optical film, wherein: The method for manufacturing the optical film comprises: Cutting out a longitudinal strip of film having a portion to be detected; When cutting the strip film, the position of the detected portion is detected, and the cutting line is positioned based on the detected position of the detected portion, thereby obtaining optical films as film sheets having the detected portion. The strip-shaped film comprises an anti-glare layer having a haze of 5.0% or more, The detected portion is a non-anti-glare portion formed locally on the anti-glare layer and having a haze of less than 1.0%. The position of the detection portion is detected using an illumination unit that radiates red light and a camera.

2. The method for producing an optical film according to claim 1, wherein: The illumination member is ring-shaped, and the method for manufacturing the optical film includes illuminating the detection portion using the illumination member.

3. The method for producing an optical film according to claim 2, wherein: The annular lighting component includes LEDs emitting red light arrayed on an annular frame having a predetermined width. The annular lighting component is configured such that the frame is inclined radially outward and the LEDs are inclined radially inward.

4. The method for producing an optical film according to claim 1, wherein: The method for manufacturing the optical film comprises: Before cutting the strip-shaped film in the width direction, detecting a single end edge of the strip-shaped film in the width direction; When cutting the strip-shaped film, the cutting member is moved from one side to the other side in the width direction of the strip-shaped film. The moving direction of the cutting member is determined based on the detected single-side end edge.

5. An optical film manufacturing device, wherein: The manufacturing device of the optical film comprises: A conveying member that conveys the strip-shaped film at a specified feeding pitch in the longitudinal direction; a detection unit including an illumination unit for illuminating a detection portion of the strip-shaped film with red light and an imaging device for imaging the illuminated detection portion, wherein the detection unit detects the detection portion; and A cutting member moves from one side to the other side in the width direction of the strip film and positions a cutting line based on the position of the detected portion. The strip-shaped film comprises an anti-glare layer having a haze of 5.0% or more, The detected portion is a non-anti-glare portion formed locally on the anti-glare layer and having a haze of less than 1.0%.

6. The manufacturing apparatus according to claim 5, wherein: The lighting component is ring-shaped.

7. The manufacturing apparatus according to claim 6, wherein: The annular lighting component includes LEDs emitting red light arrayed on an annular frame having a predetermined width. The annular lighting component is configured such that the frame is inclined radially outward and the LEDs are inclined radially inward.

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