Method for manufacturing a functional layer

Abstract

A method for manufacturing a functional layer includes: a step of conveying a strip-shaped roll (1) having a strip-shaped material to be processed (3) and a protective film (2) attached to the surface of the material to be processed (3); a step of peeling the protective film (2) from the material to be processed (3) by drawing it out from a separation member (c1) disposed on the conveying path of the roll (1); and a step of applying a coating liquid to the surface of the material to be processed (3) exposed by peeling off the protective film (2), while controlling the variation range of the tension of the protective film (2) to be below a predetermined value, while drawing out the protective film (2).

Description

Technical Field

[0001] The present invention relates to a method for continuously forming a functional layer on a strip-shaped material to be treated. Background Technology

[0002] As a method for forming various functional layers, such as hard coatings, on a strip-shaped material to be treated, there is a known method in which a coating liquid (a solution for forming functional layers) is applied to the surface of the material to be treated during the conveying of the material. In this method, to prevent damage, the material to be treated is sometimes conveyed with a protective film attached. For example, Patent Document 1 discloses a method in which a strip-shaped polycarbonate film (material to be treated), on which a protective film is respectively protected on the side to which the hard coating (functional layer) is to be formed and on the side opposite to that side, is conveyed from a conveyor along the length of the film via guide rollers, while the protective film on the side to which the hard coating is to be formed is peeled off to expose that side, and a hard coating material is applied to the exposed side and then dried, thereby forming a hard coating on the polycarbonate film.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2002-121306 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The method describes forming a functional layer by applying a coating liquid to the surface of a strip of material after the protective film has been peeled off. According to this method, a continuous film-like functional layer can be formed along the long side of the material. However, a functional layer with uneven thickness may be formed along its long side. In particular, because functional layers with optical functions require high thickness accuracy, the manufacturing method of the functional layer must be improved.

[0008] The purpose of this invention is to provide a method for manufacturing a functional layer that can continuously produce a functional layer with a generally uniform thickness.

[0009] Technical solutions for solving the problem

[0010] The inventors have thoroughly investigated the causes of uneven thickness in the functional layer. They deduced that the cause lies in the variation in the conveying speed of the material to be coated during the application of the coating liquid. Furthermore, they deduced that this variation in the conveying speed of the material to be coated is due to the force generated at the branch point during the peeling of the protective film having a component in the conveying direction of the material. They further deduced that the variation in the conveying speed of the material to be coated during the peeling of the protective film (hereinafter referred to as "speed variation") affects the material to be coated near the coating apparatus, resulting in uneven coating of the coating liquid (uneven coating thickness). Therefore, the inventors discovered that by suppressing the speed variation of the material to be coated, a functional layer of approximately uniform thickness can be continuously formed, thus completing the present invention.

[0011] [1] The manufacturing method of the present invention includes: a step of conveying a strip-shaped roll of material having a strip-shaped material to be treated and a protective film attached to the surface of the material to be treated; a step of peeling the protective film from the material to be treated by drawing it out from a separation member disposed on the conveying path of the roll; and a step of coating the surface of the material to be treated exposed by peeling off the protective film with a coating liquid, wherein the protective film is drawn out while controlling the fluctuation range of the tension of the protective film to be below a predetermined value.

[0012] [2] The preferred manufacturing method of the present invention is based on the manufacturing method of [1], wherein the roll material is conveyed along the conveying path while the tension variation is controlled to be below a specified value.

[0013] [3] The preferred manufacturing method of the present invention is based on the manufacturing method of [1] or [2], wherein a drive roller is arranged on the lead-out path of the protective film, and the protective film is led out by the drive roller.

[0014] [4] In the preferred manufacturing method of the present invention, based on the manufacturing method described in [3], the length of the protective film from the separating component to the drive roller is 1 m or more.

[0015] [5] In a preferred manufacturing method of the present invention, based on the manufacturing method of [3] or [4], a tension detector for measuring the tension of the protective film is arranged between the separating component and the driving roller, wherein the driving roller is a vacuum roller or a clamping roller.

[0016] [6] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to [5], wherein the protective film is drawn out in such a way that the standard deviation (SD1-2) of the tension of the protective film at a certain time from the start of self-control, i.e., the first time, is less than 0.01 MPa.

[0017] [7] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to [6], wherein the protective film is drawn out in such a way that the standard deviation (SD2-2) of the tension of the protective film at a certain time, i.e., a second time, up to the end of control is 0.01 MPa or less.

[0018] [8] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to [7], wherein the protective film is drawn out in such a way that the absolute value of the difference between the standard deviation (SD1-2) of the tension of the protective film at a certain time from the start of control, i.e., the first time, and the standard deviation (SD2-2) of the tension of the protective film at a certain time until the end of control, i.e., the second time, is 0.005 MPa or less.

[0019] [9] The preferred manufacturing method of the present invention is based on the manufacturing method of [8], wherein the protective film is drawn out in such a way that the absolute value of the difference between the average tension of the protective film at the first time and the average tension of the protective film at the second time is less than 0.3 MPa.

[0020]

[10] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to [9], wherein the protective film is drawn out in such a way that the standard deviation of the tension of the protective film during any certain period of time in the control is less than 0.01 MPa.

[0021]

[11] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to

[10] , wherein the protective film has a film substrate and an adhesive layer for bonding disposed on the film substrate, and a non-adhesive guide roller is disposed on the lead-out path of the protective film.

[0022]

[12] The preferred manufacturing method of the present invention is based on the manufacturing method of any one of [1] to

[11] , wherein the material to be treated is a stretch film and the coating liquid contains a liquid crystal compound.

[0023] Invention Effects

[0024] According to the manufacturing method of the present invention, since the speed variation of the material being processed can be suppressed, it is not easy to cause uneven coating of the coating liquid on the surface of the material being processed, and a functional layer with a generally uniform thickness can be continuously formed. Attached Figure Description

[0025] Figure 1 This is a schematic side view of the manufacturing apparatus for the functional layer of the first embodiment.

[0026] Figure 2 From Figure 1 The top view viewed in the direction of arrow II.

[0027] Figure 3 (a) to (d) are enlarged side views showing the layer structure of the roll material.

[0028] Figure 4 (a) is a perspective view of the non-contact conveying conversion unit (pneumatic steering rod). Figure 4 (b) is a magnified schematic side view of the vicinity of the non-contact conveying conversion section.

[0029] Figure 5 This is a perspective view of the separating component (roller) according to the first embodiment.

[0030] Figure 6 This is an enlarged side view of the protective film being peeled off from a roll of material with a certain layer structure.

[0031] Figure 7 This is an enlarged side view of the protective film being peeled off from the roll material of other layers.

[0032] Figure 8 This is a schematic side view of the manufacturing apparatus for the functional layer of the second embodiment. Detailed Implementation

[0033] In this specification, the downstream side relates to the conveying of roll materials, processed materials, and protective films, etc., and refers to the starting side for conveying them, while the upstream side refers to the side opposite to it. Furthermore, when multiple numerical ranges representing values ​​above and below the lower limit and below the upper limit are described separately, any lower limit and any upper limit can be selected to set "any lower limit above and any upper limit below".

[0034] <Summary of the Invention>

[0035] In the manufacturing apparatus and method of the present invention, during the conveying of a long strip-shaped roll having a material to be processed and a protective film, a functional layer is continuously formed on the surface of the material to be processed after the protective film is peeled off. If the protective film is peeled off, the surface of the material to be processed is exposed, and by applying a coating liquid to this surface, the aforementioned functional layer can be formed on the surface of the material to be processed. When the protective film is pulled out and peeled off, the fluctuation range of the tension of the protective film is controlled to be below a predetermined value. By pulling out the protective film while controlling the fluctuation range of the tension of the protective film to be below the predetermined value, the speed variation of the material to be processed can be suppressed.

[0036] <Manufacturing apparatus of the first embodiment>

[0037] Figure 1 This is a schematic side view of the manufacturing apparatus A for the functional layer according to the first embodiment. Figure 2This is a top view of the periphery of the separating component c1 as seen from the side of the paper. The thick arrows in each figure indicate the conveying direction of the roll 1, the blank arrows indicate the lead-out direction of the protective film 2, and the thin arrows indicate the rotation direction of various rollers or winding parts, etc.

[0038] The manufacturing apparatus A for the functional layer includes: a conveying device B that conveys a strip-shaped roll 1 along its long side; a peeling device C disposed on the conveying path of the roll 1 and peels off the protective film 2; and a coating device D disposed downstream of the peeling device C on the conveying path of the roll 1 and coating the surface of the material 3 to be processed with a coating liquid. Depending on the needs, the manufacturing apparatus A may also include a curing device E such as a drying treatment unit e1 for drying the coating liquid or a curing treatment unit e2 for curing the coating liquid, and a bonding unit F for attaching any suitable film.

[0039] [Roll Material]

[0040] The aforementioned roll 1 comprises a material to be treated 3 and a protective film 2, and may also have any suitable film and / or layer as needed. The material to be treated 3 is the object to be coated with the coating liquid. The material to be treated 3 is a thin film in the form of a long strip (also called a strip). Here, in this specification, "long strip" means a generally rectangular shape when viewed from above, with the length in the long side direction being sufficiently longer than the length in the width direction. The length in the long side direction is, for example, 5 times or more than 5 times the length in the width direction, preferably 10 times or more. The width direction is a direction orthogonal to the long side direction. The material to be treated 3 may itself have mechanical strength sufficient to be conveyed by the conveying device B along the long side direction, or it may not have such mechanical strength. In the case where the material to be treated 3 does not have such mechanical strength, the material to be treated 3 is conveyed by the conveying device B in a state of being laminated on a support film (a film having the aforementioned mechanical strength). In the following description, when it is necessary to distinguish between the treated material having the aforementioned mechanical strength and the treated material not having mechanical strength, the former will be referred to as "first treated material 31" and the latter as "second treated material 32," and when both are included, they will be simply referred to as "treated material 3." The treated material 3 has two large-area surfaces. The surface of the treated material 3 is either of the two large-area surfaces, and is the surface on which the coating liquid is applied (the treated surface). Hereinafter, the surface of the treated material 3 opposite to the surface (the other large-area surface) will be referred to as the "opposite surface" of the treated material 3.

[0041] The protective film 2 described above is a film that prevents damage to the surface of the material 3 being treated. The protective film 2 is attached to the surface of the material 3 being treated in a peelable state. The protective film 2 has at least a film substrate. The protective film 2 may also have an adhesive layer for bonding on one side of the film substrate, as needed. In addition, the protective film 2 may also have any suitable film and / or layer.

[0042] Figure 3 Examples of several layer structures of roll material 1 are shown.

[0043] Figure 3 (a) and (b) are examples of a roll 1 having a first treated material 31 (a treated material 3 having strength capable of being conveyed along its long side by the conveying device B). The roll 1 of Figure (a) has, from the paper surface side, the first treated material 31 and a protective film 2 having a bonding adhesive layer 22 and a film substrate 21. The roll 1 of Figure (b) has, from the paper surface side, a suitable film 41, the first treated material 31, and a protective film 2 having a bonding adhesive layer 22 and a film substrate 21. The protective film 2 of these rolls 1 is peelably attached to the treated material 3 via the bonding adhesive layer 22. Therefore, after the protective film 2 is pulled out, it peels off from the surface of the first treated material 31 and the boundary of the bonding adhesive layer 22, resulting in the surface of the first treated material 31 being exposed. It should be noted that, for example, the protective film 2 can also be directly attached to the surface of the first material to be treated 31 in a peelable state by means of pseudo-adhesion of the film substrate 21 to the first material to be treated 31. In this case, the protective film 2 does not have the aforementioned adhesive layer (not shown).

[0044] Figure 3 (c) and (d) are examples of a roll 1 having a second processed material 32 (a processed material 32 without the strength to be conveyed along the long side by the conveying device B). The roll 1 in Figure (c) sequentially comprises, from the paper surface side, a support film 42, the second processed material 32, and a protective film 2 having a film substrate 21 but without a bonding adhesive layer. The roll 1 in Figure (d) sequentially comprises, from the paper surface side, a suitable film 41, a support film 42, the second processed material 32, and a protective film 2 having a film substrate 21 but without a bonding adhesive layer. When the protective film 2 is pulled out, it peels off from the surface of the second processed material 32 at the boundary with the protective film 2 (film substrate 21), resulting in the surface of the second processed material 32 being exposed. The support film 42 is a film that supports the second processed material 32 in a manner that allows it to be conveyed by the conveying device B. The support film 42 uses a film with mechanical strength capable of being conveyed along the long side by the conveying device B.

[0045] Examples of the first material to be treated 31 include, for instance, resin films. From a material perspective, the first material to be treated 31 is not particularly limited, and examples include polyvinyl alcohol resins, cycloalkene resins, polycarbonate resins, polyvinyl acetal resins, polyimide resins, acrylic resins, cellulose ester resins, cellulose resins, polyester resins, polyester carbonate resins, olefin resins, and polyurethane resins. Preferably, a resin film comprising one or more of the following resins can be used: polycarbonate resin, polyvinyl acetal resin, cellulose ester resin, polyester resin, and polyester carbonate resin. One of these resins can be used alone, or two or more can be used in combination. Furthermore, from an optical perspective, the first material to be treated 31 can also be an optically anisotropic film or an optically isotropic film. Examples of such optically functional films include polarizing films, phase retardation films, light diffusion films, brightness enhancement films, anti-glare films, and light reflection films. Alternatively, the first material to be processed 31 may be a film with orientation limiting force, such as a stretched film stretched in a specified direction.

[0046] The thickness of the first material to be processed 31 is not particularly limited, for example, it is 10μm to 200μm, preferably 12μm to 100μm.

[0047] Examples of the second material to be treated 32 include, for example, an adhesive layer, an anti-glare layer, an anti-reflective layer, and a hard coating. The thickness of the second material to be treated 32 is not particularly limited. When the second material to be treated 32 is an adhesive layer, its thickness is, for example, 0.5 μm to 50 μm, preferably 1 μm to 30 μm.

[0048] Examples of materials that can be used as the film substrate 21 constituting the protective film 2 include resin films, synthetic paper, and paper. Preferably, the film substrate 21 is a resin film with excellent transparency, and more preferably, a resin film with excellent transparency and optical isotropy. When the film substrate 21 is a resin film, its material is not particularly limited, and examples include polyester resins such as polyethylene terephthalate or polybutylene terephthalate, olefin resins such as polyethylene or polypropylene, diene resins such as polybutadiene, vinyl chloride resins such as polyvinyl chloride or vinyl chloride copolymers, polymethylpentene, polyurethane, and ethylene-vinyl acetate copolymers. One or more of these materials can be used alone. The thickness of the film substrate 21 is not particularly limited, but is, for example, 5 μm to 200 μm, preferably 10 μm to 100 μm.

[0049] When the protective film 2 has an adhesive layer 22 for bonding, examples of adhesive layers 22 include colorless and transparent acrylic adhesives, rubber adhesives, silicone adhesives, polyurethane adhesives, vinyl alkyl ether adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, and cellulose adhesives. The thickness of the adhesive layer 22 is not particularly limited, but is, for example, 0.1 μm to 50 μm, preferably 1 μm to 30 μm.

[0050] As the suitable film 41 described above, any suitable film can be used. The suitable film 41 can be a single-layer structure or a multilayer structure with two or more layers. In addition, when the suitable film 41 is a multilayer structure, it may also contain any suitable layer (e.g., adhesive layer 22 for bonding). Furthermore, the suitable film 41 described above can be a film with optical functions as described above, or it can be an optically isotropic film.

[0051] The support film 42 is not particularly limited as long as it is a film with mechanical strength. Examples of support films 42 include resin films, synthetic paper, and paper. It is preferable to use a resin film with excellent transparency as the protective film 2, as exemplified, as the support film 42. The thickness of the support film 42 is not particularly limited, for example, from 5 μm to 200 μm, preferably from 10 μm to 100 μm.

[0052] [Conveying device]

[0053] Reference Figure 1 and Figure 2 Conveying device B is a device that conveys the roll material 1 along its long side. Conveying device B conveys the roll material 1 in a roll-to-roll manner. During the conveying path, the layer structure of the roll material 1 changes after the protective film 2 is peeled off and after a functional layer is formed on the surface of the material to be processed 3. Even though the layer structure changes in this way, the roll material 1 must still contain the material to be processed 3 throughout the entire conveying path. Hereinafter, when it is necessary to distinguish the terms in the description, the roll material 1 from the time the protective film 2 is peeled off to the time the functional layer is formed will be called "processing roll material 11", the roll material 1 after the functional layer is formed on the surface of the material to be processed 3 will be called "product roll material 12", and the entire period from roll-out to roll-up will be called "roll material 1".

[0054] Specifically, the conveying device B includes: a roll-out section b1 on which a roll of material 1 is mounted; a take-up section b2 that takes up the product roll 12; and a conveying section b3 that continuously conveys the roll 1 along its long side from the roll-out section b1 to the take-up section b2. The roll 1 rolled out from the roll-out section b1 is conveyed along the conveying path of the conveying section b3, and is taken up by the take-up section b2 after being transformed from the processing roll 11 into the product roll 12.

[0055] The aforementioned winding section b1, winding section b2, and conveying section b3 of the conveying device B for the roll material 1 can be conventionally known mechanical types. For example, the winding section b1 of the conveying device B uses an actuator such as a motor with a brake and a winding shaft, and the winding section b2 uses an actuator such as a motor with a clutch and a winding shaft. For example, the conveying section b3 of the conveying device B has a tension detector (not shown) such as an upstream feed roller b31, multiple guide rollers b32, a downstream feed roller b33, and a tension pickup roller. It should be noted that the conveying section b3 of the conveying device B may also have a feed roller (not shown), or a tension adjusting roller (not shown). The conveying device B for the roll material 1 conveys the roll material 1 along its long side while controlling the fluctuation range of the tension of the roll material 1 to below a predetermined value. That is, the conveying device B controls the fluctuation range of the tension of the roll material 1 during conveying to be minimized. As a method for controlling the tension described above, examples include speed control based on the tension of the roll 1 measured by a tension detector (e.g., changing the difference in circumferential speed between the two feed rollers), and / or torque control (e.g., changing the torque of the roll-out section b1).

[0056] The aforementioned conveying unit b3 may, as needed, include a non-contact conveying conversion unit b34 that changes the conveying direction of the processing roll 11 containing the material to be processed 3. This non-contact conveying conversion unit b34 is disposed between the peeling device C and the coating device D. The non-contact conveying conversion unit b34 is a portion that changes the conveying direction of the processing roll 11 containing the material to be processed 3 in a manner that prevents the surface of the material to be processed 3 exposed by peeling off the protective film 2 from contacting foreign objects. These foreign objects include, for example, mechanical parts such as guide rollers.

[0057] Specifically, downstream of the separating component c1, the processing roll 11, including the exposed surface of the material to be processed 3, is reversed after its opposite side comes into contact with the guide roller b32, and its surface is reversed without contact with the non-contact conveying conversion section b34. In the illustrated example, between the peeling device C and the coating device D, the processing roll 11 (the material to be processed 3) is reversed in a hairpin shape by the non-contact conveying conversion section b34.

[0058] As a non-contact conveying conversion unit b34, a pneumatic steering rod can be used, for example. Figure 4 (a) shows an example of a pneumatic steering rod. The pneumatic steering rod, which is a non-contact conveying conversion unit b34, has a hollow housing b342 with numerous blowout holes b341 and a supply port b343 for supplying air into the housing b342. As shown by the arrow in Figure (b), the air supplied from the supply port b343 passes through the blowout holes b341 and is blown out from the outer surface of the housing b342, thereby changing the direction of the processing roll 11 containing the processed material 3 without contacting the surface of the processed material 3 with the pneumatic steering rod b34.

[0059] [Stripping device]

[0060] The peeling device C is a device that peels the protective film 2 off the material to be processed 3 (roll 1) midway through the conveying of the roll 1 along the long side. The surface of the material to be processed 3 is exposed by peeling off the protective film 2, and the exposed surface of the material to be processed 3 is conveyed by the conveying device B along the long side.

[0061] The peeling device C includes a separating component c1 that serves as a fulcrum, a tension control section c2 that leads out the protective film 2 while controlling the fluctuation range of the tension of the protective film 2 to below a predetermined value, a guide roller c3, and a recovery section c4 that winds up and recovers the led-out protective film 2. The peeling device C, including the separating component c1, is disposed in the transport path of the roll 1. The separating component c1 has an arcuate surface c12 with a radius of curvature of 30 mm or less, and the arcuate surface c12 extends along the width direction of the roll 1. The arcuate surface c12 of the separating component c1 is grounded in contact with the protective film 2.

[0062] In this embodiment, a roller with a radius of 30 mm or less is used as the separating component c1. Figure 5 This is a perspective view of a roller c111 with a radius of 30 mm or less, which serves as a separating component c1. Hereinafter, to distinguish it from guide rollers, the roller used as the separating component c1 will be referred to as "separating roller c111". The aforementioned separating roller c111, for example, has a cylindrical portion c112 and a pair of shaft portions c113 disposed on both sides of the cylindrical portion c112. Figure 2 As shown, the shaft portion c113 of the separating roller c111 is mounted on a bearing c114 fixed to a frame or the like in the manufacturing apparatus A. Regarding the cylindrical portion c112, examples include cylinders whose circumferential surface is made of metal such as stainless steel, or cylinders whose circumferential surface is made of rubber (including elastomers) or synthetic resin. In the separating roller c111, the cylindrical portion c112 extends parallel to the width direction and contacts the protective film 2 of the roll 1. It should be noted that the cylindrical portion c112 of the separating roller c111 is formed (because it is circular when viewed from the side) with an arcuate surface c12 having a radius of curvature of 30 mm or less at any point on its circumference. The radius of the cylindrical portion c112 of the separating roller c111 is preferably 25 mm or less, and more preferably 20 mm or less. The lower limit of the radius of the cylindrical portion c112 of the aforementioned separating roller c111 is theoretically greater than zero, but in reality it is more than 1 mm, preferably more than 3 mm.

[0063] The aforementioned separating roller c111 may be rotatable (able to rotate on its own axis) or non-rotatable. For smooth extraction of the protective film 2, the separating roller c111 is preferably rotatable. In this case, the shaft portion c113 of the separating roller c111 may be supported by a bearing c114 to allow rotation, or the shaft portion c113 may be fixed to the bearing c114 and the cylindrical portion c112 may be rotatably mounted on the shaft portion c113.

[0064] The aforementioned tension control unit c2 includes a drive roller c21 disposed on the lead-out path of the protective film 2, a tension detector c22 disposed between the separation member c1 and the drive roller c21 and measuring the tension of the protective film 2, and a control unit (not shown) including a computer that controls the tension of the protective film 2 based on the tension measured by the tension detector c22. The drive roller c21 is not particularly limited and can be, for example, a vacuum roller, a clamping roller, etc. Figure 1 In this example, a vacuum roller is used as the drive roller c21. A vacuum roller has numerous suction holes on its circumferential surface, through which the protective film 2 is drawn out while being attracted. It should be noted that the drive roller c21, such as a vacuum roller or clamping roller, is also called a tension cutting roller.

[0065] The tension control unit c2 draws out the protective film 2 while controlling the fluctuation range of the tension of the protective film 2 to below a predetermined value. The drawn-out protective film 2 is conveyed in the drawing path and is finally wound up by the recovery unit c4. The tension of the protective film 2 to be controlled is the tension of the protective film 2 between the separation member c1 and the drive roller c21. The length of the protective film 2 from the separation member c1 to the drive roller c21 (the path length between the separation member c1 and the drive roller c21) can be appropriately set. The longer the distance from the separation member c1 to the drive roller c21, the more likely a functional layer with a substantially uniform thickness can be formed. Therefore, the length of the protective film 2 from the separation member c1 to the drive roller c21 is preferably long. In specific values, the length of the protective film 2 from the separation member c1 to the drive roller c21 is 1 m or more, preferably 5 m or more, and more preferably 10 m or more. There is no particular upper limit to the above length, but in practice, it is, for example, 30 m or less.

[0066] As a method for controlling the tension of the protective film 2, one example is changing the rotational speed of the drive roller c21 based on the tension of the protective film 2 measured by the tension detector c22. The rotational speed of the upstream feed roller b31 is controlled by the conveying device B of the roll 1. The control unit (not shown) of the protective film 2 changes the tension of the protective film 2 by changing the rotational speed of the drive roller c21 based on the measured tension of the protective film 2 (i.e., by changing the difference between the circumferential speed of the drive roller c21 and the circumferential speed of the upstream feed roller b31), and controls the fluctuation range to below a predetermined value.

[0067] It should be noted that when the drive roller c21 is a clamping roller, the drive roller c21 (clamping roller) can also serve as the separation component c1. That is, the drive roller or driven roller of the clamping roller can also be used as the separation component c1. In the case where a clamping roller is used as both the separation component c1 and the drive roller c21, the length of the protective film 2 from the separation component c1 to the drive roller c21 is 0m.

[0068] Guide roller c3 is positioned on the lead-out path of the protective film 2 between the separating component c1 and the recycling section c4. One guide roller c3 may be provided at a suitable location, but typically two or more are provided at suitable locations. As described later, when the protective film 2 has a bonding adhesive layer 22, at least the guide roller c3 in contact with the bonding adhesive layer 22 is preferably a non-adhesive guide roller. Figure 1 In the diagram, the guide roller c3, indicated by reference numeral c31, is in contact with the adhesive layer 22 for bonding. A non-adhesive guide roller refers to a roller whose circumferential surface is not adhered to or is difficult to adhere to with adhesive. Examples of non-adhesive guide rollers include rollers with a circumferential surface covered by silicone rubber, rollers with a circumferential surface covered by silicone resin, rollers with a circumferential surface covered by fluoropolymer resin, and rollers whose circumferential surface has been roughened by sandblasting or similar processes. By using the aforementioned non-adhesive guide rollers, when the protective film 2 having the adhesive layer 22 for bonding is wound into the recovery section c4, it is possible to prevent the adhesive from adhering to the guide roller.

[0069] The recovery section c4 is the part that winds up the protective film 2 that has been drawn out, and uses an actuator such as a geared electric motor with a winding shaft.

[0070] By drawing out the protective film 2 using the drive roller c21, the roll 1 is separated into a processing roll 11 containing the material to be processed 3 and the protective film 2 at the exit side of the arcuate surface c12 of the separating member c1 (separating roller c111). The drawn-out protective film 2 is bent along the circumference of the arcuate surface c12 and simultaneously wound from the drive roller c21 to the recovery section c4. The processing roll 11 is conveyed by the conveying device B. It should be noted that the drawing-out speed (recovery speed) of the protective film 2 is approximately equal to the conveying speed of the roll 1.

[0071] The angle (referred to as the "peel angle") between the conveying direction of the aforementioned processing roll 11 and the lead-out direction of the aforementioned protective film 2 is appropriately set. It should be noted that... Figure 1In the figure, the conveying direction of the processing roll 11 containing the material to be processed 3 is indicated by a double-dotted line, the lead-out direction of the protective film 2 is indicated by a dotted-dotted line, and the peel angle is indicated by the reference numeral α. The larger the peel angle, the more effectively the speed variation of the material to be processed 3 (processing roll 11) can be suppressed. Therefore, the peel angle is preferably large. Specifically, the lower limit of the peel angle α is, for example, 45 degrees or more, preferably 60 degrees or more, and more preferably 70 degrees or more. The upper limit of the peel angle α is, for example, 180 degrees or less, preferably 150 degrees or less, and more preferably 120 degrees or less. The peel angle α can be adjusted, for example, by changing the position of the drive roller c21 (the peel angle can be increased or decreased). Figure 1 The example shown illustrates a peeling angle of approximately 90 degrees. Alternatively, one or more guide rollers (not shown) can be arranged between the separating component c1 and the drive roller c21. With this guide roller arrangement, the peeling angle can be adjusted by changing the position of the guide roller near the separating component c1.

[0072] [Coating apparatus]

[0073] The coating apparatus D is a device for applying a coating liquid to the exposed surface of the material to be treated 3. The coating apparatus D is not particularly limited as long as it can apply the coating liquid to the surface of the material to be treated 3; examples include, for instance, a die coater, a lip coater, a gravure coater, a reverse coater, a bar coater, and a doctor blade coater. Figure 1 In this example, a slit coater d1 is used as a coating apparatus D. The die lip of the slit coater d1 is arranged opposite to the surface of the material 3 to be treated. In addition, a rear roller d2 is arranged on the opposite side of the die lip, separated by a processing roll 11.

[0074] Here, the conveying length of the material 3 (processing roll 11) from the peeling device C to the coating device D can be appropriately set. It should be noted that the conveying length can also be referred to as the path length. The longer the conveying length, the more effectively the speed variation of the material 3 can be suppressed. Therefore, the conveying length is preferably long; specifically, it is 1 m or more, preferably 5 m or more, and more preferably 10 m or more. There is no particular upper limit to the conveying length, but in practice, it is, for example, 20 m or less.

[0075] If the conveying length of the above-mentioned processed material 3 (processing roll material 11) from the peeling device C to the coating device D is made long, the manufacturing device A will become large-sized. However, by providing the above-mentioned non-contact conveying conversion section b34, a long conveying length can be ensured while preventing the device from becoming large-sized. In particular, by using the non-contact conveying conversion section b34, it is possible to prevent foreign matter from coming into contact with the surface of the processed material 3 during the conveyance of the above-mentioned processed material 3 (processing roll material 11) from the peeling device C to the coating device D. Therefore, it is possible to coat the coating liquid on the surface of the processed material 3 without damaging the surface thereof to form a functional layer with a substantially uniform thickness.

[0076] [Curing device (Japanese: キュアリング装置)]

[0077] The curing device E is arranged on the downstream side of the coating device D as required.

[0078] The curing device E is provided to change the coating liquid from a liquid state to a solid state. It should be noted that when the coating liquid naturally changes to a solid state during the conveyance of the processed roll material 11 after coating the coating liquid, the above-mentioned curing device E can be omitted.

[0079] The curing device E has, for example, a drying treatment section e1. The drying treatment section e1 is not particularly limited as long as it can dry the coating liquid. For example, a blower that blows heated air or normal-temperature air, a far-infrared heater, etc. are used. In addition, when the coating liquid contains a photocurable resin such as an ultraviolet-curable resin, the curing device E has a curing treatment section e2 that irradiates light such as ultraviolet rays.

[0080] [Laminating section]

[0081] The laminating section F is a part where an arbitrary appropriate film 43 such as a protective film is attached to the product roll material 12 (processed roll material 11 formed with a functional layer).

[0082] The laminating section F has a supply roll f1 that unwinds an appropriate film 43, and a clamping roll f2 that laminates the above-mentioned film 43 on the product roll material 12.

[0083] [Manufacturing method of functional layer]

[0084] The manufacturing method of the functional layer includes: a step of conveying a long strip-shaped roll material 1 having a processed material 3 and a protective film 2; a step of peeling the protective film 2 from the processed material 3 by pulling out the protective film 2 on a separating member c1 arranged on the conveying path of the above-mentioned roll material 1; a step of coating a coating liquid on the surface of the processed material 3 exposed by peeling the protective film 2. The manufacturing method of the present invention is implemented using, for example Figure 1 the manufacturing device A shown.

[0085] [Conveying step of roll material]

[0086] The roll 1 is rolled out from the roll-out section b1 and conveyed by the conveying section b3. The conveying speed of the roll 1 is not particularly limited, for example, it is 3 m / min or more and 30 m / min or less, preferably 5 m / min or more and 20 m / min or less.

[0087] While controlling the variation in tension of the roll 1 to below a specified value, the roll 1 is conveyed. From the viewpoint of suppressing speed variations in the processed material 3 (processing roll 11), the variation in tension of the roll 1 is preferably as small as possible. The aforementioned variation in tension refers to the variation in tension of the roll 1 within a time period shorter than the conveying time of the total length of the roll 1 to be controlled. In this specification, "time" refers to the length between two points in time. The total length of the roll 1 to be controlled is the length along the long side of the roll 1 conveyed during the period from the start of tension control to the end of control. Hereinafter, the "total length of the roll to be controlled" will be referred to as the "control length of the roll," and the "period from the start of tension control to the end of control" will be referred to as the "entire control period."

[0088] The variation range of the tension of the specific roll 1 can be represented by, for example, the standard deviation over a specified time period. For instance, the standard deviation (SD1-1) of the tension of the roll 1 at the first time period is 0.04 MPa or less, preferably 0.02 MPa or less, and more preferably 0.01 MPa or less. Furthermore, the standard deviation (SD2-1) of the tension of the roll 1 at the second time period is 0.04 MPa or less, preferably 0.02 MPa or less, and more preferably 0.01 MPa or less. It should be noted that the lower limits of the aforementioned standard deviations (SD1-1) and (SD2-1) are theoretically zero, but are generally greater than zero.

[0089] The aforementioned first time refers to a certain period of time starting from the beginning of tension control of roll 1. For example, the aforementioned first time is a period of time equivalent to 2% to 5% of the controlled length of roll 1 from the beginning of tension control of roll 1. The aforementioned second time refers to a certain period of time ending from the end of tension control of roll 1. For example, the aforementioned second time is a period of time equivalent to 2% to 5% of the controlled length of roll 1 from the end of tension control of roll 1. However, because the tension value of roll 1 is unstable after tension control begins, the aforementioned beginning of control does not refer to a strictly defined starting moment, but rather to a moment when operation is stable after control begins.

[0090] Furthermore, the tension of the roll 1 is controlled while being conveyed to maintain a substantially constant tension throughout the entire control period. The term "substantially constant tension" means that when the entire control period is divided into multiple equal time periods, the average tension within each of these multiple time periods represents substantially the same value. For example, the absolute value of the difference between the maximum and minimum average tensions within the multiple time periods can be 0.2 MPa or less, preferably 0.09 MPa or less. For instance, the absolute value of the difference between the average tension of the roll 1 at the first time period and the average tension of the roll 1 at the second time period is controlled to be 0.09 MPa or less, preferably 0.05 MPa or less. It should be noted that the lower limit of the above absolute value is zero. As long as the difference between the average tension during a certain period from the start of control (i.e., the first time period) and the average tension during a certain period until the end of control (i.e., the second time period) is such a small value, it can be deduced that the tension of the roll 1 is substantially constant throughout the entire control period.

[0091] The tension per unit cross-sectional area of ​​the conveyed roll 1 is not particularly limited, for example, it is set in the range of 0.5 MPa or more and 2.9 MPa or less, preferably in the range of 0.8 MPa or more and 2.6 MPa or less.

[0092] Here, the units “MPa” for tension, average tension and standard deviation of tension of roll 1 represent the tension per unit cross-sectional area of ​​the roll section orthogonal to the thickness direction.

[0093] [Protective film peeling process]

[0094] The protective film 2 is led out from the exit side of the separating component c1, and the protective film 2 is led out along the arcuate surface c12 of the separating component c1.

[0095] Figure 6 This indicates that the protective film 2 will be removed from... Figure 3 (a) shows the state of the layered roll 1 peeled off from the aforementioned separating member c1. Figure 7 This indicates that the protective film 2 will be removed from... Figure 3 (c) shows the state of the layered roll 1 peeled off from the separation member c1.

[0096] In transport Figure 6 In the case of the roll material 1, the protective film 2 has an adhesive layer 22 for bonding and a film substrate 21. Therefore, if the protective film 2 is pulled out, it separates at the interface between the adhesive layer 22 and the processed material 3 (first processed material 31) on the exit side of the separating member c1. During transport Figure 7In the case of the roll material 1, the protective film 2 does not have an adhesive layer 22 for bonding. Therefore, if the protective film 2 is pulled out, it separates at the interface between the protective film 2 (film substrate 21) and the processed material 3 (second processed material 32) on the exit side of the separation member c1.

[0097] As described above, the materials to be processed 3 (the first material to be processed 31 and the second material to be processed 32) are not particularly limited. For example, as the first material to be processed 31, a film with orientation-restricting force, such as a stretch film, can be used. In addition, as the second material to be processed 32, an adhesive layer can be used.

[0098] The aforementioned films with orientation-restricting forces, i.e., stretched films, are not particularly limited, and examples include cycloalkenyl resin films, cellulose resin films, ester resin films with ester bonds in the main chain such as polyester, polyarylate, and polycarbonate, acrylic resin films, and styrene resin films. The stretching methods for these stretched films are not particularly limited, and examples include: uniaxial stretching methods such as stretching the film uniaxially along its long side (longitudinal uniaxial stretching method), stretching the film uniaxially along its width (transverse uniaxial stretching method); simultaneous biaxial stretching methods such as stretching the film uniaxially along its long side and width simultaneously, and progressive biaxial stretching methods such as stretching the film uniaxially along one direction (longitudinal and width) and then stretching it in the other direction; and stretching the film uniaxially along an inclined direction that is neither parallel nor perpendicular to the width direction (inclined stretching method). Stretched films generally possess orientation-restricting forces that uniformly align the liquid crystal compound in a direction parallel to the stretching direction. If a coating liquid containing a liquid crystal compound is applied to the surface of such a stretched film, a functional layer is formed in which the liquid crystal compound is oriented parallel to the stretching direction.

[0099] As the aforementioned stretch film, any known film or film known after the disclosure of this invention can be used. For example, the stretch film described in Japanese Patent Application Publication No. 2020-183980 can be used. For details regarding the aforementioned stretch film, please refer to the aforementioned publication.

[0100] The adhesive layer, which is the second material to be treated 32, is formed of a transparent material with adhesive properties. Examples of adhesive base materials for forming the adhesive layer include acrylic adhesives, rubber adhesives, silicone adhesives, polyester adhesives, polyurethane adhesives, epoxy adhesives, and polyether adhesives. From the viewpoints of transparency, processability, and durability, acrylic adhesives are preferred.

[0101] As the aforementioned adhesive layer, a known adhesive layer or an adhesive layer known after the disclosure of this invention can be used. For example, the base adhesive described in Japanese Patent No. 6194358 can be used as the adhesive layer (second treated material 32) of this invention. For details regarding the aforementioned base adhesive, please refer to the aforementioned publication.

[0102] Reference Figure 1 , Figure 6 and Figure 7 The protective film 2 is drawn out along the arcuate surface c12 of the separating member c1. When the protective film 2 is drawn out, the protective film 2 and the material to be treated 3 separate at a point (branch point S) on the circumference of the arcuate surface c12 of the separating member c1, resulting in a processing roll 11 and the protective film 2 exposed on the surface of the material to be treated 3. The processing roll 11 is conveyed by the conveying device B to the coating device D, and the peeled-off protective film 2 is drawn out along the arcuate surface c12 of the separating member c1 and collected by the recycling unit c4.

[0103] While controlling the variation range of the tension of the protective film 2 to below a predetermined value, the protective film 2 is drawn out. As mentioned above, the tension of the protective film 2 to be controlled refers to the tension of the protective film 2 between the separation member c1 and the drive roller c21. From the viewpoint of suppressing the speed variation of the processed material 3 (processing roll 11), the variation range of the tension of the protective film 2 is preferably as small as possible. The variation range of the tension refers to the variation range of the tension of the protective film 2 within a time shorter than the drawing time of the total length of the protective film 2 to be controlled. The total length of the protective film 2 to be controlled is the length of the long side of the protective film 2 drawn out during the period from the start of tension control to the end of control. Hereinafter, the "total length of the protective film to be controlled" will be referred to as the "control length of the protective film", and the "period from the start of tension control to the end of control" will be referred to as the "entire control period".

[0104] The variation range of the tension of the protective film 2 can be represented by, for example, the standard deviation over a specified time period. For instance, the standard deviation (SD1-2) of the tension of the protective film 2 at the first time period is 0.01 MPa or less, preferably 0.008 MPa or less, and more preferably 0.007 MPa or less. Furthermore, the standard deviation (SD2-2) of the tension of the protective film 2 at the second time period is 0.01 MPa or less, preferably 0.008 MPa or less, and more preferably 0.007 MPa or less. It should be noted that the lower limits of the aforementioned standard deviations (SD1-2) and (SD2-2) are theoretically zero, but are generally greater than zero.

[0105] Furthermore, the absolute value of the difference between the standard deviation (SD1-2) of the tension of the protective film 2 at the first time and the standard deviation (SD2-2) of the tension of the protective film 2 at the second time is, for example, 0.005 MPa or less, preferably 0.003 MPa or less. As long as the difference is such, the variation range of the tension at the first time and the second time remains substantially unchanged, and the protective film is stably drawn out.

[0106] The aforementioned first time refers to a certain period of time starting from the beginning of tension control of the protective film 2. For example, the aforementioned first time is a period of time equivalent to 2% to 5% of the controlled length of the protective film 2 from the beginning of tension control of the protective film 2. The aforementioned second time refers to a certain period of time ending from the end of tension control of the protective film 2. For example, the aforementioned second time is a period of 2% to 5% of the controlled length of the protective film 2 from the end of tension control of the protective film 2. However, because the tension value of the protective film 2 is unstable after the tension control of the protective film 2 begins, the aforementioned beginning of control does not refer to a strictly defined starting moment, but rather to a moment when operation stabilizes after the control begins.

[0107] In particular, more preferably, the protective film 2 is introduced in such a way that the standard deviation of the tension of the protective film 2 is 0.01 MPa or less (preferably 0.008 MPa or less, more preferably 0.007 MPa or less) for any given period of time during the tension control of the protective film 2. This "any given period of time" is, for example, a length of 2% to 5% of the control length of the protective film 2, and the starting point of this period can be any moment as long as the protective film 2 is controlled. This "any given period of time" can be the first time mentioned above, or the second time mentioned above, or any other time.

[0108] As long as the standard deviation of the tension of the protective membrane 2 is below 0.01 MPa within any given time period during the tension control, the variation range of the tension throughout the entire control remains essentially unchanged, and the protective membrane is stably drawn out.

[0109] Furthermore, the protective film 2 is drawn out while maintaining a substantially constant tension throughout the control period. This substantially constant tension means that when the entire control period is divided into multiple equal time periods, the average tension within each of these multiple time periods represents substantially the same value. For example, if the absolute value of the difference between the maximum and minimum values ​​of the average tensions within the multiple time periods is 0.3 MPa or less, this can be considered. For instance, the absolute value of the difference between the average tension of the protective film 2 at the first time period and the average tension of the protective film 2 at the second time period is controlled to be 0.3 MPa or less, preferably 0.1 MPa or less, and more preferably 0.05 MPa. It should be noted that the lower limit of the absolute value is zero. As long as the difference between the average tension during a certain period from the start of control (i.e., the first time period) and the average tension during a certain period until the end of control (i.e., the second time period) is such a small value, it can be deduced that the tension of the protective film 2 is substantially constant throughout the control period.

[0110] The tension per unit cross-sectional area of ​​the protective film 2 to be controlled is not particularly limited, for example, it is set in the range of 0.8 MPa or more and 3.1 MPa or less, preferably in the range of 1.0 MPa or more and 2.6 MPa or less, and more preferably in the range of 1.1 MPa or more and 2.0 MPa or less.

[0111] Here, the units “MPa” for the tension, average tension, and standard deviation of tension of the protective membrane 2 represent the tension per unit cross-sectional area of ​​the membrane section orthogonal to the thickness direction.

[0112] The protective film 2, drawn out by the drive roller c21, is wound up by the recovery section c4. Because the drive roller c21 is a tension cutting roller, the tension of the protective film 2 between the drive roller c21 and the recovery section c4 does not affect the tension between the drive roller c21 and the separating component c1. Therefore, the tension of the protective film 2 between the drive roller c21 and the recovery section c4 can be controlled, or it can be left uncontrolled. The recovery section c4 only needs to wind up the protective film 2 drawn out by the drive roller c21. For example, the recovery section c4 winds up the protective film 2 with a certain torque.

[0113] [Coating process of coating liquid and formation of functional layer]

[0114] If the protective film 2 separates at the outlet side of the separation member c1, the treatment roll 11 exposed on the surface of the material being treated 3 is conveyed to the downstream side. The treatment roll 11 is conveyed to the coating apparatus D via the non-contact conveying conversion unit b34.

[0115] A coating liquid is applied to the surface of the material to be treated 3 using a coating apparatus D. The coating liquid is a material for forming the functional layer. The coating liquid is not particularly limited; any suitable coating liquid can be used depending on the functional layer to be formed. When using the film with orientation-restricting force as the material to be treated 3, a coating liquid containing, for example, a liquid crystal compound is used. The liquid crystal compound is preferably a polymerizable liquid crystal compound; as an example of such a polymerizable liquid crystal compound, the polymerizable liquid crystal compound described in Japanese Patent Application Publication No. 2020-183980 can be used. For details regarding the polymerizable liquid crystal compound, the coating liquid containing it, and the orientation method of the polymerizable liquid crystal compound, please refer to the aforementioned publication. Furthermore, when using the adhesive layer as the material to be treated 3, a coating liquid containing, for example, a refractive index adjusting material is used. As an example of a coating liquid containing a refractive index adjusting material, a dispersion liquid in which a high refractive index material is dispersed in a solvent, as described in Japanese Patent Publication No. 6194358, can be used. For details regarding the dispersions and coating methods for dispersing high-refractive-index materials in solvents, please refer to the aforementioned publication.

[0116] The coating thickness (film thickness) of the coating liquid is not particularly limited, but is, for example, 5 nm or more and 30 μm. In the case of the coating liquid containing a liquid crystal compound, the coating thickness is, for example, 0.5 μm or more and 30 μm or less, preferably 1 μm or more and 15 μm or less. In the case of the coating liquid containing a refractive index adjusting material, the coating thickness is, for example, 5 nm or more and 10 μm or less, preferably 10 nm or more and 5 μm or less.

[0117] After the coating liquid is applied to the surface of the material to be treated 3, the coating film is dried in the drying treatment unit e1 as needed. The drying method is not particularly limited, and examples include natural drying, heat drying, and reduced pressure drying. Alternatively, in cases where polymerization via light is required, such as with polymerizable liquid crystal compounds, the material is irradiated with ultraviolet light or similar light in the curing treatment unit e2.

[0118] By hardening or curing the coating in this way, a functional layer is formed on the surface of the material being treated 3. This functional layer is formed continuously along the long side direction of the material being treated 3 as the roll 1 is conveyed. For example, when the material being treated 3 is a film with orientation-restricting force and the coating liquid contains the liquid crystal compound, a phase retardation layer (functional layer) is formed on the surface of the material being treated 3. Furthermore, when the material being treated 3 is an adhesive layer and the coating liquid contains the refractive index adjusting material, a refractive index adjusting separating layer (functional layer) is formed on the surface of the adhesive layer, which is the material being treated 3.

[0119] As needed, a film 43 (protective film, etc.) is applied to the surface of the functional layer on the product roll 12, where the above-mentioned functional layer is formed, through the bonding part F. The resulting product roll 12 is then wound by the winding part b2.

[0120] As in this invention, by controlling the variation in tension of the protective film 2 to below a predetermined value while drawing out the protective film 2, the speed variation of the material to be processed 3 can be effectively suppressed. Specifically, if the tension varies significantly when the protective film is drawn out, this tension variation will cause the material to be processed to be alternately stretched by a strong force and then stretched by a weaker force on the drawing-out side. Therefore, it is presumed that the speed variation of the material to be processed will increase when the protective film is drawn out. In this regard, as in this invention, by controlling the variation in tension of the protective film 2 to below a predetermined value, the speed variation of the material to be processed 3 (processing roll 11) when drawing out the protective film 2 can be effectively suppressed.

[0121] Furthermore, by controlling the variation in tension of the roll 1 to below a predetermined value while conveying the roll 1, speed variation of the roll 1 (processing roll 11) during the withdrawal of the protective film 2 can be further suppressed. In particular, by controlling the tension of the protective film 2 to be approximately constant throughout the control period, speed variation of the roll 1 (processing roll 11) during the withdrawal of the protective film 2 can be further suppressed. In addition, by setting the length of the protective film 2 from the separation member c1 to the drive roller c21 to be 1m or more, even if the protective film 2 wobbles due to the drive roller c21, such wobbling is less likely to be transmitted to the processed material 3.

[0122] According to the present invention, since the speed variation of the processed material 3 (processing roll 11) can be suppressed, uneven coating of the coating liquid on the surface of the processed material 3 is less likely to occur, and a functional layer with a substantially uniform thickness can be continuously formed. That is, when the conveying speed of the processed material is high, the coating thickness of the coating liquid becomes thinner, and when the conveying speed of the processed material is slow, the coating thickness becomes thicker, but by suppressing the speed variation of the processed material 3, uneven coating can be prevented.

[0123] Furthermore, as in this invention, by extending the protective film 2 along the arcuate surface c12 with a radius of curvature of 30 mm or less, it is possible to suppress the speed variation of the processed material 3 when peeling the protective film 2 from the processed material 3. The reason for this is not yet clear, but it is speculated that it is because, in the case of an arcuate surface c12 with a radius of curvature of 30 mm or less, the branch point S (the boundary between the protective film 2 and the processed material 3) is less likely to shift towards the extension side of the protective film 2. If the branch point S shifts towards the extension side of the protective film 2 (in... Figure 6 and Figure 7If the material is offset (towards the lower side of the paper), the force component in the conveying direction generated on the material being processed will be minimized at the branch point S due to the stretching of the protective film 2. Therefore, speed variation of the material being processed 3 (processing roll 11) can be suppressed. Because the material being processed 3 (processing roll 11) is less prone to speed variation, uneven coating of the coating liquid on the surface of the material being processed 3 is less likely to occur, and a functional layer with approximately uniform thickness can be formed. On the other hand, it is speculated that in the case of a large arc surface with a radius of curvature greater than 30 mm, because the material being processed follows the protective film and shifts significantly on the lead-out side, the force component in the conveying direction generated on the material being processed will increase at the branch point, and the speed variation of the material being processed will increase due to the reaction force when the protective film separates.

[0124] Furthermore, by setting the peeling angle to 60 degrees or more and 180 degrees or less to draw out the protective film 2, the speed variation of the processed material 3 can be further suppressed. In addition, by setting the conveying length of the processed material 3 (processing roll 11) from after peeling off the protective film 2 to before applying the coating liquid to 1 m or more, even if the processed material 3 experiences a slight speed variation during the peeling off of the protective film 2, it can be prevented that such variation will affect the vicinity of the coating apparatus D.

[0125] <Manufacturing apparatus of the second embodiment>

[0126] In the first embodiment described above, a vacuum roller is used as the drive roller c21, but for example, it can also be used as follows: Figure 8 The diagram shows a clamping roller as the drive roller c21. The clamping roller conveys the protective film 2 by clamping it between a pair of rollers c211 and c212 (first roller c211 and second roller c212). Either the first roller c211 or the second roller c212 can be the drive roller and the other can be the driven roller, or both can be drive rollers. When a roller has a large contact area relative to the protective film 2, it is preferably the drive roller. In the illustrated example, at least the first roller c211 is the drive roller. The second roller c212 can be a roller that rotates with the drive of the first roller c211 (driven roller), or it can also be the drive roller.

[0127] <Manufacturing apparatus of the third embodiment>

[0128] In the first embodiment described above, a separating member c1 with an arcuate surface c12 is used, wherein the arcuate surface c12 has a radius of curvature of 30 mm or less. However, a separating roller with a radius of curvature greater than 30 mm can also be used as the separating member c1 (not shown). Alternatively, a blade can also be used as the separating member c1 (not shown).

[0129] Example

[0130] The present invention will be further described in detail below with reference to embodiments and comparative examples. However, the present invention is not limited to the embodiments described below.

[0131] <Example 1>

[0132] [Manufacturing Equipment]

[0133] use Figure 1 The manufacturing apparatus A shown includes a conveying device B, a peeling device C for peeling, a coating device D, a curing device E, and a bonding device F. To briefly describe the apparatus other than the peeling device, the conveying device is one that conveys the roll material while controlling the tension to minimize fluctuations and maintain a relatively constant tension. The coating device uses a conventional slot coater, the curing device uses a conventional drying device and ultraviolet irradiation device, and the bonding device uses a conventional bonding and separation membrane device.

[0134] The peeling device uses a tension control unit that controls the tension to minimize fluctuations in the tension of the protective film and to keep the tension of the protective film approximately constant. The specifications of each component of the peeling device are as follows.

[0135] Separation component: a metal roller with a radius of 25mm.

[0136] Drive roller: A vacuum roller with a radius of 102 mm (manufactured by Katsura Roller Mfg.Co.,Ltd. under the product name "suction").

[0137] Tension detector: A product name of Mitsubishi Electric Corporation.

[0138] The length of the protective film from the separation component to the drive roller is approximately 6m.

[0139] Recovery section: An existing actuator that winds the protective film onto the take-up shaft with a certain torque.

[0140] [Roll-in fabric and coating liquid]

[0141] like Figure 3 As shown in (a), the roll material consists of an adhesive layer (acrylic adhesive), a film substrate (a transparent polyethylene terephthalate film with a thickness of 80 μm), and a material to be treated (a cycloolefin resin film stretched along an inclined direction; manufactured by Zeon Corporation of Japan under the product name "Zeonor"). The width of the roll material is approximately 1330 mm.

[0142] The coating liquid used is the coating liquid containing a liquid crystal compound used in Example A1 of Japanese Patent Application Publication No. 2020-183980.

[0143] The manufacturing apparatus is started up as a whole, and under the following conditions, while conveying the roll material through the conveying device, the protective film (adhesive layer for bonding + film substrate) is peeled off and recovered from the roll material through the peeling device, and the coating liquid is applied to the processing roll material through the coating device and cured to continuously produce the product roll material.

[0144] The operation lasted approximately 8000 seconds.

[0145] It should be noted that because the tension of the roll material and the protective film are controlled simultaneously with the start of operation of the manufacturing equipment, the entire period from the start to the end of operation is the control period for the tension of the roll material and the protective film. Furthermore, because the recovery section winds up the protective film with a certain torque, the tension of the protective film between the vacuum roller and the recovery section changes according to the winding diameter.

[0146] Conveying speed of roll material: 10m / minute.

[0147] The suction force of the vacuum roller is 7 kPa.

[0148] Peeling angle of protective film: 84 degrees.

[0149] [Results of tension measurement of the roll material and protective film in Example 1]

[0150] The tension of the protective film is measured from the moment several tens of seconds after the start of operation (i.e., the moment when operation stabilizes) until the moment when operation ends. Regarding the tension of the protective film, the tension between the separating component and the drive roller is measured using a tension detector. The sampling interval for the protective film tension is 1 second.

[0151] The standard deviation of the protective film tension for 300 seconds from the moment of stable operation is 0.006 MPa, and the average tension of the protective film during this period is 2.35 MPa. Furthermore, the standard deviation of the protective film tension for 300 seconds until the end of operation (between 7700 and 8000 seconds after operation) is 0.005 MPa, and the average tension of the protective film during this period is 2.35 MPa. Additionally, the standard deviation of the protective film tension for 300 seconds starting 4000 seconds after the start of operation is 0.006 MPa. The 300 seconds from the moment of stable operation corresponds to the first time period, and the 300 seconds until the end of operation corresponds to the second time period.

[0152] [Evaluation of the Functional Layer in Example 1]

[0153] The functional layer (cured layer of liquid crystal compound) formed in the first time step and the functional layer (cured layer of liquid crystal compound) formed in the second time step of Example 1 were each cut into length × width = 1000 mm × 1320 mm, and these functional layers were visually evaluated. Because the above-mentioned functional layers have phase difference characteristics, the above-mentioned functional layers were sandwiched between two polarizing films arranged in orthogonal Nicol, backlight was irradiated from one polarizing film side, and visual observation was performed from the other polarizing film side.

[0154] In Example 1, almost no difference in color intensity was observed in the functional layer (cured layer of liquid crystal compound) formed in the first time interval and the functional layer formed in the second time interval. Therefore, it can be evaluated that a functional layer with approximately uniform thickness has been formed.

[0155] <Comparative Example 1>

[0156] In Comparative Example 1, a guide roller was used instead of the drive roller (vacuum roller) of Example 1. Otherwise, the manufacturing apparatus of Comparative Example 1 was the same as that of Example 1, and the product roll was continuously manufactured by feeding the roll material while peeling off the protective film and applying the coating liquid, just as in Example 1.

[0157] [Results of tension measurement of the roll material and protective film in Comparative Example 1]

[0158] Regarding Comparative Example 1, the tension of the protective film was measured at the same sampling interval as in Example 1.

[0159] As a result, the standard deviation of the protective membrane tension during the first time period (300 seconds from the moment of stable operation) was 0.0113 MPa, and the average tension of the protective membrane during this period was 2.25 MPa. Furthermore, the standard deviation of the protective membrane tension during the second time period (300 seconds until the end of operation) was 0.0267 MPa, and the average tension of the protective membrane during this period was 1.875 MPa. Additionally, the standard deviation of the protective membrane tension during the 300 seconds following the start of operation (4000 seconds after the start of operation) was 0.0199 MPa.

[0160] [Evaluation of the functional layer in Comparative Example 1]

[0161] Regarding Comparative Example 1, the functional layers formed in the first time and the functional layers formed in the second time were also cut out, and these functional layers were visually evaluated in the same manner as in Example 1.

[0162] In Comparative Example 1, no significant color variation was observed in the functional layer formed in the first time interval. However, in Comparative Example 1, significant color variation was observed in the functional layer formed in the second time interval. Therefore, the functional layer formed in Comparative Example 1 in the second time interval can be characterized as having uneven thickness.

[0163] Explanation of reference numerals in the attached figures

[0164] Manufacturing facility A

[0165] B Conveying device

[0166] C-stripping device

[0167] The rounded surface of the C12 separation component

[0168] C2 Tension Control Unit

[0169] C21 drive roller

[0170] D Coating Device

[0171] 1, 11, and 12 roll materials

[0172] 2 Protective film

[0173] 3, 31, and 32 are the materials being processed.

Claims

1. A method for manufacturing a functional layer, comprising: A process of conveying a strip-shaped roll of material to be processed and a protective film attached to the surface of the material to be processed; The process of peeling the protective film off the material being processed by extending the protective film from a separation member disposed on the conveying path of the roll material; The process of applying a coating liquid to the surface of the material being treated, exposed by peeling off the protective film. While controlling the tension variation of the protective film to below a specified value, the protective film is drawn out. The protective film is drawn out in such a way that the standard deviation of the tension of the protective film is less than 0.01 MPa for a certain period of time, i.e., the first time, starting from the start of self-control.

2. The method for manufacturing the functional layer according to claim 1, wherein, The roll material is conveyed along the conveying path while the tension variation is controlled to be below a specified value.

3. The method for manufacturing the functional layer according to claim 1 or 2, wherein, A drive roller is provided on the lead-out path of the protective film, and the protective film is led out by the drive roller.

4. The method for manufacturing the functional layer according to claim 3, wherein, The length of the protective film from the separating component to the drive roller is 1m or more.

5. The method for manufacturing the functional layer according to claim 3, wherein, A tension detector for measuring the tension of the protective film is disposed between the separating component and the drive roller. The drive roller is a vacuum roller or a clamping roller.

6. The method for manufacturing the functional layer according to claim 1 or 2, wherein, The protective film is drawn out in such a way that the standard deviation of the tension of the protective film is less than 0.01 MPa for a certain period of time up to the end of control, i.e., the second time.

7. The method for manufacturing the functional layer according to claim 1 or 2, wherein, The protective film is introduced in such a way that the absolute value of the difference between the standard deviation of the tension of the protective film at a certain time from the start of self-control (i.e., the first time) and the standard deviation of the tension of the protective film at a certain time from the end of control (i.e., the second time) is less than 0.005 MPa.

8. The method for manufacturing a functional layer according to claim 7, wherein, The protective film is drawn out in such a way that the absolute value of the difference between the average tension of the protective film at the first time and the average tension of the protective film at the second time is less than 0.3 MPa.

9. The method for manufacturing a functional layer according to claim 1 or 2, wherein, The protective film is drawn out in such a way that the standard deviation of the tension of the protective film within any given time period during control is less than 0.01 MPa.

10. The method for manufacturing a functional layer according to claim 1 or 2, wherein, The protective film has a film substrate and an adhesive layer for bonding disposed on the film substrate. Non-adhesive guide rollers are arranged on the lead-out path of the protective film.

11. The method for manufacturing a functional layer according to claim 1 or 2, wherein, The material being treated is a stretch film, and the coating liquid contains a liquid crystal compound.

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