TW201345818A - Web roll and manufacturing method of the same, and manufacturing method of optical sheet - Google Patents

Abstract

A splicing tape in the shape of a belt is adhered to an outer circumferential surface of a winding core. The splicing tape includes a base, a winding-core-side adhesive layer, and a film-side adhesive layer. The base is in the form of a belt. The winding-core-side adhesive layer is formed on one of surfaces of the base. The film-side adhesive layer is formed on the other of surfaces of the base. In a state that a part of the film-side adhesive layer is exposed from a leading edge of a polymer film, a remaining part of the film-side adhesive layer is adhered to an edge portion of the polymer film, such that the edge portion is fixed to the winding core. The base and the adhesive layers serve as a buffer. The polymer film which is laminated on the leading edge next is gently curved, and therefore a sectional outline does not stand out on a surface of the polymer film.

Description

Mesh roll, method of manufacturing the same, and method of manufacturing optical sheet

The present invention relates to a web roll, a method of manufacturing the same, and a method of manufacturing an optical sheet.

The polymer film is widely used as an optical film or the like because it has excellent light transmittance and flexibility and can be made into a thin film. Among them, a cellulose ester film such as cellulose halide is used for the optical film. The optical film is represented by a photo-sensing film, and is a protective film or a retardation film of a polarizing plate which is a constituent member of a liquid crystal display device which has been expanding in market size in recent years.

The polymer film is continuously produced into a strip shape by a melt film forming method or a solution film forming method. The polymer film is wound up in a roll shape, for example, into a cylindrical core, and stored as a film roll and transported.

As shown in FIG. 8, when the polymer film 3 is wound around the winding core 2, the leading end 3a of the film 3 is fixed to the winding core 2 by the bonding tape 4 or the like so that the leading end 3a of the film 3 does not fall off from the winding core 2. The bonding tape 4 is formed with adhesive layers 4b and 4c on both surfaces of the support 4a. Further, the outer peripheral surface 2a of the winding core 2 is joined to the bonding tape 4 via the adhesive layer 4b. Further, the film front end portion is fixed to the winding core 2 via the adhesive layer 4c.

When the long-sized polymer film 3 is wound into the winding core 2 in the form of a roll, at a position overlapping with the leading end (cut) 3a of the film 3, a step drop 5 called a so-called slit transfer appears in the second volume. After the film surface. The step drop 5 also depends on the type of the web or the winding condition of the long-sized polymer film 3, but there is also a step difference from a portion where the winding starts to a portion above the 100th roll. The slit transfer constituted by the step drop 5 is required to be flat A slippery planar web, such as an optical film, becomes a malfunction and causes a large loss.

Therefore, various methods for reducing the transfer of slits have been proposed. For example, Japanese Patent Publication No. Hei 8-244035 discloses that the knurls which are thickened at both side edges in the width direction of the web are wound up so as to decrease in thickness from the core side to the outer peripheral side. Further, in Japanese Laid-Open Patent Publication No. Hei 9-58935, a convex step portion having a height of 1 to 10 times the thickness of the film wound back is formed on the outer peripheral portions of both ends of the cylindrical core. Further, in Japanese Laid-Open Patent Publication No. 2001-63876, a joint tape is attached to the outer peripheral portions of both ends of the cylindrical core in place of the convex step portion. In this way, a convex step drop or a bonding tape is provided on the outer peripheral portions of both ends of the core, or knurling is provided on both side edges of the mesh to cause a surface pressure applied to the web at the central portion in the radial direction. Low, thereby suppressing the generation of slit transfer.

However, as disclosed in Japanese Laid-Open Patent Publication No. Hei 8-244035, it is extremely difficult to reduce the amount of protrusion of the knurl, and there is a problem that the knurling device is complicated. Further, as disclosed in Japanese Laid-Open Patent Publication No. Hei 9-58935, it is necessary to align the both side edges of the mesh with the step falling portion in the step of providing the step falling portion on the outer peripheral surfaces of both ends. In Japanese Laid-Open Patent Publication No. 2001-63876, it is necessary to attach a bonding tape to both end portions of the core, and it is also necessary to align the both side edges of the mesh, and there is a problem that the winding needs to be skillfully performed.

An object of the present invention is to provide a web roll which suppresses generation of slit transfer, a method for producing the same, and a method for producing an optical sheet.

In the web roll of the present invention, the belt-like web is wound around the core, and includes a core, a mesh, a joining member, a support, a core-side adhesive layer, and a mesh-side adhesive layer. A mesh is wound around the core. The mesh is wound around the outer peripheral surface of the core. In the joint member, the front end portion of the mesh is fixed to the outer peripheral surface of the winding core. The support body is provided to the joint member. The core side adhesive layer is provided on the joint member and adhered to the core. The core side adhesive layer is formed on one of the surfaces of the support. The mesh side adhesive layer is provided to the joining member and adheres to the front end portion of the mesh, whereby the front end portion of the mesh is fixed to the winding core. The mesh side adhesive layer is formed on the other side of the support. The front end portion of the mesh coats the mesh side adhesive layer in a state in which the exposed blank portion is provided on the mesh side adhesive layer.

It is preferable that the blank portion is provided with a cushioning material.

The cushioning material is formed thicker than the thickness of the mesh and is composed of an elastic member, the bomb The member is deformed to a thickness smaller than the mesh by the web being taken up to the core.

The leading end of the mesh is cut into an inclination angle θ 1 with respect to the width direction of the mesh in the range of -30° < θ 1 < 30°, and the joint member is attached to the roll in parallel with the front end of the mesh. The core is preferred.

The mesh is preferably an optical film.

It is preferable that the optical film is an optical sheet by cutting into a sheet shape.

The web roll manufacturing method of the present invention includes a sticking step (A step), a kit step (B step), a fixing step (C step), and a winding step (D step), and the strip web is taken up to the core To make a mesh roll. In the step A, the joining member is attached to the core. The joining member includes a support, a first adhesive layer, and a second adhesive layer. The support is in the form of a strip. The first adhesive layer is formed on one of the surfaces of the support and adhered to the core. The second adhesive layer is formed on the other surface of the support. In the step B, the core to which the joining member is attached is set in the web take-up position. In the step C, the front end portion of the mesh is fixed to the winding core via the joining member. The exposed blank portion is provided on the second adhesive layer by covering a portion of the second adhesive layer with the front end portion of the mesh. In step D, the web is taken up to the core by rotating the core.

It is preferable that the blank portion is provided with a cushioning material which is elastically deformed.

The cushioning material is formed to be thicker than the thickness of the mesh and is composed of an elastic member that is deformed to a thickness smaller than the mesh by being wound up to the core by the mesh.

The front end of the web is cut into an inclination angle θ 1 with respect to the width direction of the web in the range of -30 ° < θ 1 < 30 °, and in the step A, the joint member is parallel to the front end of the web It is preferred that the ground surface is applied to the outer peripheral surface of the winding core.

The method for producing an optical sheet according to the present invention includes a attaching step (E step), a setting step (F step), a fixing step (G step), a winding step (H step), a drawing step (I), and a cutting step (J step) ). In the E step, the joining member is attached to the core. The joining member includes a support, a first adhesive layer, and a second adhesive layer. The support is in the form of a strip. The first adhesive layer is formed on one of the surfaces of the support and adhered to the core. The second adhesive layer is formed on the other surface of the support. In the F step, the core to which the joining member is attached is set in the winding position. In the G step, the front end portion of the optical film is fixed to the winding core via the joining member. The exposed blank portion is provided on the second adhesive layer by covering a portion of the second adhesive layer with the front end portion. In the H step, the optical film is taken up to the core by rotating the core. In the first step, the wound optical film is taken out from the core. J step In the step, the optical film taken out from the core is cut into a sheet to form an optical sheet.

According to the invention, each of the adhesive layers of the joint member functions as an elastic member. Therefore, when the next web is wound around the front end of the web, the joint member functions as a cushion to prevent the next web from coming into contact with the front end of the web to be a slit transfer.

2, 23‧‧ ‧ core

2a, 23a‧‧‧ outer perimeter

3, 15‧‧‧ polymer film

3a, 15a‧‧‧ film front end

4, 31‧‧‧ joint tape

4a, 31a‧‧‧Support

4b, 4c‧‧‧ adhesive layer

5‧‧‧ step difference

10‧‧‧film roll manufacturing equipment

11‧‧‧ film production line

12‧‧‧ knurling device

13‧‧‧Winding device

15b‧‧‧Front end of film

16‧‧‧Support roller

17‧‧‧Rolling roll

18, 19‧‧ ‧ displacement department

21‧‧‧ turret arm

22‧‧‧Winding shaft

25‧‧‧ Guide arm

26, 28‧‧‧ Guide roller

27‧‧‧ Arm mounting shaft

29‧‧‧ Film roll

31b‧‧‧core side adhesive layer

31c‧‧‧film side adhesive layer

32‧‧‧Blank Department

40‧‧‧ cushioning material

40a‧‧‧ upstream side edge

41‧‧‧Joint tape

BL1‧‧‧ film width direction reference line

L2‧‧‧ length

PS1‧‧‧rolling position

PS2‧‧‧core replacement position

W1‧‧‧Width

θ 1‧‧‧ tilt angle

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a film roll manufacturing apparatus embodying the present invention.

Fig. 2 is a plan view showing a state in which a film front end is attached to a winding core.

Figure 3 is a cross-sectional view taken along line III-III of Figure 2.

Fig. 4 is a cross-sectional view corresponding to the line III-III of Fig. 2 in a state in which the film is wound twice at the tip end portion of the film.

Fig. 5 is a cross-sectional view corresponding to the line III-III of Fig. 2, showing a bonding tape according to a second embodiment of the present invention.

Fig. 6 is a cross-sectional view corresponding to the line III-III of Fig. 2 in a state in which the film is wound twice at the tip end portion of the film.

Fig. 7 is a plan view showing a third embodiment of the present invention in a state in which a film tip is attached to a winding core.

Fig. 8 is a cross-sectional view showing a state in which a film front end is attached to a winding core by a conventional bonding tape.

As shown in Fig. 1, a film roll (mesh roll) manufacturing apparatus 10 for carrying out the present invention has a film production line 11, a knurling device 12, and a winding device 13. The film production line 11 is not shown, and has a casting device, a tenter, and a drying device in this order from the upstream side. The film production line 11 produces a strip polymer film 15 such as a TAC (triacetate cellulose) film by a solution film forming method.

The knurling device 12 is disposed between the film production line 11 and the winding device 13. The knurling device 12 has a support roller 16, a knurling roller 17, and displacement portions 18, 19. When the knurling is imparted, the support roller 16 and the knurling roller 17 are moved to the nip position by the displacement portions 18, 19, and knurling is formed on both side edges (edges) of the polymer film 15 by embossing (not shown). Show).

The take-up device 13 has a turret arm 21 that winds the polymer film 15 onto a winding core 23 that is fitted to the take-up shaft 22. The turret arm 21 is intermittently rotated by 180 degrees by an arm driving portion (not shown) to selectively switch the winding core 23 between the winding position PS1 and the winding core replacement position PS2. Further, a guide arm 25 is provided at an intermediate position in the rotational direction of the turret arm 21, and a guide roller 26 is attached to the distal end portion of the guide arm 25. The guide roller 26 supports the polymer film 15 as the turret arm 21 rotates to prevent the polymer film 15 from coming into contact with the turret arm 21 or the arm mounting shaft 27.

The take-up shaft 22 is disposed at a front end portion of the turret arm 21, and the take-up shaft 22 is provided with a winding core 23. At the winding position PS1, the polymer film 15 fed from the guide roller 28 is taken up to the winding core 23. Further, at the winding core replacement position PS2, the film roll 29, which is wound up to a constant amount of the polymer film 15 and has a constant amount, for example, is wound from the take-up shaft 22 together with the winding core 23. Further, at the core replacement position PS2, a new empty core 23 is placed on the take-up shaft 22, and the core 23 is replaced.

At the winding position PS1, if the polymer film 15 of a predetermined length is taken up to the winding core 23 and the film roll 29 is brought into a state of full winding, the turret arm 21 is rotated by 180 degrees so that the film roll 29 close to the full roll is placed on the roll. Core replacement position PS2. And, the new empty core 23 is positioned to the take-up position PS1. When the film roll 29 has a predetermined length, the film cutting device (not shown) is actuated to cut the polymer film 15. For the film cutting device, for example, a mesh rewinding device described in Japanese Patent Laid-Open Publication No. 2005-89177, or Japanese Patent Laid-Open Publication No. 2008-230723, and the like. The rear end portion of the cut film is taken up to the film roll 29 at the core replacement position PS2. Then, after the cutting, the leading end portion of the film is taken up to the empty core 23 at the winding position PS1.

Similarly, in the same manner, the polymer film 15 is taken up to the winding core 23, whereby the polymer film 15 continuously fed as the film roll 29 becomes a product. The polymer film 15 has an optical film such as a polarizing plate protective film or a retardation film. Further, in the film roll 29 thus obtained, the polymer film 15 is taken out from the core 23 and cut into a desired size, and used as a sheet-like polarizing plate protective film (polarizing plate protective sheet) or a retardation film (phase difference) sheet). Further, an optically anisotropic layer, an antireflection layer, an antiglare function layer or the like is applied to the polymer film 15 to be used as a highly functional film.

As shown in FIG. 2, a strip-shaped bonding tape (joining member) 31 is attached to the empty core 23. The bonding tape 31 is used to fix the front end portion (hereinafter referred to as a film front end portion) 15b of the polymer film 15 to the winding core 23. The bonding tape 31 is attached to the outer peripheral surface 23a of the winding core 23 by the core side adhesive layer (first adhesive layer) 31b (see FIG. 3).

As shown in FIG. 3, the bonding tape 31 is provided with a belt-shaped support body 31a, a core side adhesive layer 31b, and a film side adhesive layer (second adhesive layer) 31c. The support 31a is made of PET (polyethylene terephthalate). The core side adhesive layer 31b is formed on one of the faces of the support body 31a (back The film side adhesive layer 31c is formed on the other surface (surface) of the support body 31a. The thickness of the support 31a is in the range of 10 μm or more and 40 μm or less, more preferably 10 μm or more and 35 μm or less, and more preferably 10 μm or more and 30 μm or less. The core side adhesive layer 31b may be adhered to the core 23 or the polymer film 15, and may be formed on the entire surface of the back surface of the support 31a. The thickness of the core-side adhesive layer 31b is preferably in the range of 10 μm or more and 50 μm or less, more preferably 10 μm or more and 40 μm or less, and more preferably 20 μm or more and 40 μm or less.

As shown in FIG. 2 and FIG. 3, the film side adhesive layer 31c is formed on the entire surface of the support body 31a, and is formed of the same composition and the same thickness as the core side adhesive layer 31b, but may be different in composition or difference. thickness of. Although not shown, a release tape is attached to the surface on which the film-side adhesive layer 31c is formed (the surface of the polymer film 15 to be attached). The release tape is peeled off before the polymer film 15 is wound up after the bonding tape 31 is attached to the core 23 by the core side adhesive layer 31b. As the bonding tape 31, for example, Nitto Denko Co., Ltd. (models: 5601, 5603, 5605, 5608, 5610, 5612) is used.

As shown in FIG. 4, when the polymer film 15 is wound up and the next polymer film 15 is superposed on the film front end 15a, the core side adhesive layer 31b and the film side adhesive layer 31c of the bonding tape 31 function as a cushioning material. In the polymer film 15, the film front end 15a is aligned with a blank in the film side adhesive layer 31c, and the front end portion covers a part of the film side adhesive layer 31c and is attached to the film side adhesive layer 31c. In such a manner that the blank portion 32 is provided on the film-side adhesive layer 31c by exposing a part of the film-side adhesive layer 31c, the film front end portion 15b is adhered to the film-side adhesive layer 31c and fixed to the winding core 23. Therefore, compared with the bonding method based on the conventional bonding tape shown in Fig. 8, a polymer film is formed into a slowly curved shape under the overlap of the film leading end 15a. Therefore, since there is no extreme deformation as in the related art, surface transfer can be suppressed.

The attachment of the bonding tape 31 or the film front end portion 15b can be performed manually based on the adhesion of the bonding tape 31, or can be automatically performed by using a film sticking device having a film cutting blade. At the time of manual operation, a film reservoir (not shown) is provided in front of the winding device 13 (near the upstream side). By the film reservoir, a film having a corresponding amount of time required for cutting the polymer film 15 or fixing to the core 23 is temporarily accumulated, and the cutting of the polymer film 15 and the winding to the core 23 are performed during the storage period. . The film corresponding to the time corresponds to the film of the length delivered during the period. Further, when the film is automatically carried out, the film 15 is cut and fixed to the core 23 by using a film sticking device. At this time, the bonding tape 31 on the core 23 is detected, and the polymerization is cut according to the detection timing. In the film 15, the cut film leading end 15a is positioned at the position where the blank portion 32 is formed, and the film leading end portion 15b is joined to the film side adhesive layer 31c.

In the present embodiment, the film front end 15a is formed along the width direction of the polymer film 15. That is, the film front end 15a is parallel to the film width direction. However, as in the third embodiment (see FIG. 7) to be described later, the film front end 15a may be formed so as to be inclined (intersected) with respect to the film width direction.

Further, in the present embodiment, the bonding tape 31 is disposed so as to be along the core direction of the winding core 23 in the longitudinal direction of the bonding tape 31. The winding core direction of the core 23 coincides with the width direction of the polymer film 15.

When the thickness of the polymer film 15 is t0, the thickness t1 of the bonding tape 31 is set to (0.5 × t0). T1 (1.5 × t0) is preferred. The thickness t1 of the bonding tape 31 is (0.5 × t0) or more, whereby the cushioning effect can be more reliably achieved than when it is less than (0.5 × t0). Further, the thickness t1 of the bonding tape 31 is equal to or less than (1.5 × t0), whereby the slit transfer is less likely to occur than when it exceeds (1.5 × t0). Further, when the thickness of each of the adhesive layers 31b and 31c is t2, (0.4 × t1) T2 (0.5 x t1) is preferred. The thickness t2 of each of the adhesive layers 31b and 31c is (0.4 × t1) or more, whereby the cushioning effect can be obtained more reliably than when it is smaller than (0.4 × t1). When the thickness t2 of each of the adhesive layers 31b and 31c is larger than (0.5 × t1), the closer to (0.5 × t1) the buffer effect becomes larger, and the effect of suppressing the slit transfer is improved.

Further, the width of the polymer film 15 is not particularly limited, and is preferably 600 mm or more, and more preferably 1400 mm or more and 2500 mm or less. Further, the present invention also has an effect when the width of the polymer film 15 is more than 2,500 mm. The thickness of the polymer film 15 is preferably in the range of 30 μm or more and 200 μm or less, more preferably in the range of 40 μm or more and 150 μm or less, and further preferably in the range of 40 μm or more and 100 μm or less. The length of the polymer film 15 is preferably 2,000 m or more, more preferably 4,000 m or more and 8,000 m or less. Further, the film roll 29 preferably has a winding radius of 450 mm or more, and more preferably 650 mm or more and 920 mm or less.

The length L2 of the bonding tape 31 in the core direction of the winding core 23 is not particularly limited, and it is preferable that the width W1 of the polymer film 15 is L2 = (W1 - 0) mm - (W - 10) mm. By setting such a length L2, the slit transfer is suppressed almost over the entire surface of the film.

The polymer which becomes a raw material of the polymer film 15 is not specifically limited. Solution system In the film method, for example, a cellulose halide or a cyclic polyolefin or the like is used. In the melt film forming method, for example, a cellulose halide, a lactone-containing cyclic polymer, a cyclic polyolefin, a polycarbonate, or the like is used. Further, the details of the cellulose halide are described in paragraphs [0140] to [0195] of Japanese Patent Laid-Open Publication No. 2005-104148. These descriptions can also be applied to the present invention. Further, a solvent, a plasticizer, a deterioration inhibitor, an ultraviolet absorber (UV agent), an optical anisotropy control agent, and a solvent are also described in detail in paragraphs [0196] to [0516] of Japanese Patent Laid-Open Publication No. 2005-104148. Additives such as retardation inhibitors, dyes, matting agents, strippers, and stripping accelerators.

Next, a second embodiment of the present invention will be described with reference to Figs. 5 and 6 . The same components as those in the first embodiment are denoted by the same reference numerals and the description thereof will not be repeated. Further, the illustration of the polymer film 15 is omitted in FIG. In the second embodiment, the bonding tape 41 is disposed on the blank portion 32 on the front side (downstream side) in the rotation direction of the winding core 23 in the first embodiment. The cushioning material 40 is preferably thicker than the polymer film 15, and is elastically deformed to have a thickness smaller than that of the polymer film 15. The material and the like are not particularly limited as long as the cushioning material 40 can be elastically deformed without causing a bad influence on the polymer film 15 . For example, it is manufactured by Nitto Denko Co., Ltd. (model: 5606, 5608), manufactured by Teraoka Manufacturing Co., Ltd. (NO. 7075), and manufactured by TESA Co., Ltd. (NO. 4980).

In the second embodiment, the cushioning material 40 is attached to the blank portion 32 in a shape protruding upward from the blank portion 32. Therefore, by pressing the film leading end 15a to the upstream side edge 40a of the cushioning material 40 in the rotational direction of the winding core 23, it is easy to perform the alignment at the time of joining. Further, by the winding of the polymer film 15, even if the next polymer film 15 is superposed on the film front end 15a, the next polymer film 15 is returned by the buckling force of the cushioning material 40. Therefore, the extreme bending deformation to the polymer film 15 as in the prior art disappears, and the generation of the slit transfer caused by the pressing of the next polymer film 15 to the film leading end 15a is suppressed. The cushioning material 40 is formed in a strip shape, but the cross-sectional shape is not limited to a rectangular shape, and may be a semicircular shape, a trapezoidal shape, or any other shape.

As shown in Fig. 7, in the third embodiment, the inclination angle θ 1 of the film leading end 15a with respect to the film width direction reference line BL1 is set to 16°. At this time, the bonding tape 31 is attached to the winding core 23 at the same inclination angle θ 1 in accordance with the inclination angle θ 1 of the film leading end 15a. Further, the film width direction reference line BL1 is a line which is uniform along the film width direction.

Thus, the inclination angle θ 1 is an angle formed by the film leading end 15a and the film width direction reference line BL1. The inclination angle θ 1 may be 0° as in the first embodiment, and may be in the third embodiment. It is not an angle of 0°. The inclination angle θ 1 of the film leading end 15a with respect to the film width direction reference line BL1 is preferably in the range of -30° < θ 1 < 30°, and more preferably in the range of -20° < θ 1 < 20°, -10°. A range of <θ 1 < 10° is further preferable. This is because the closer the inclination angle θ 1 is to 0°, the less the stress caused by the influence of the film surface pressure which is overlapped at the film leading end 15a, whereby the slit transfer is further suppressed.

In the second embodiment, when the bonding tape 41 in which the cushioning material 40 is disposed is used, the film leading end 15a can be inclined with respect to the film width direction reference line BL1 in the same manner as in the third embodiment. In the same manner as in the third embodiment, the bonding tape 41 is used to be inclined at the same inclination angle θ 1 as the film leading end 15a with respect to the film width direction reference line BL1.

In the above-described respective embodiments, the method of manufacturing the film roll 29 in which the polymer film 15 is wound into a roll form has been described. However, the polymer film 15 is not limited to the other types of mesh which can be used for the surface transfer problem. invention. Further, in each of the above embodiments, the polymer film 15 is adhered to the winding core 23 by using the bonding tapes 31 and 41. However, instead of the bonding tapes 31, 41, the polymer film 15 may be bonded to the core by a binder.

Next, in order to confirm whether or not the present invention has an effect, the following experiment was conducted. The experiment as the present invention is "Example", and the experiment conducted as a control is "Comparative Example". In the film roll manufacturing apparatus 10 shown in Fig. 1, a TAC-based film roll 29 having a length of 5000 m, a width of 1500 mm, and a thickness of 80 μm was produced. In the first embodiment, the bonding tape 31 shown in Figs. 2 and 3 is used, and the film leading end 15a is attached as shown in Fig. 4 . In the second embodiment, the same conditions as in the first embodiment were used except that the bonding tape 41 shown in Figs. 5 and 6 was used. In the third embodiment, the inclination angle θ 1 of the film leading end 15a shown in Fig. 7 is set to 16°, and the bonding tape 31 is attached to the winding core 23 in parallel with the film leading end 15a, and is otherwise provided. The same conditions as in Example 1. In the fourth embodiment, the inclination angle θ 1 of the film leading end 15a of the third embodiment is set to 20°, and the same as in the third embodiment. In the fifth embodiment, the inclination angle θ 1 of the film leading end 15a of the third embodiment is set to 25°, and the same as the third embodiment. In the same manner as in the third embodiment, the inclination angle θ 1 of the film leading end 15a of the third embodiment was set to 30°. In Comparative Example 1, the film front end 15a was attached to the winding core 23 by using the bonding tape 4 of the conventional type shown in Fig. 8, and the same conditions as in the first embodiment were employed. With respect to Comparative Example 1, in Comparative Example 2, the inclination angle of the film leading end 15a was set to 30°, and the peripheral was replaced by this. The same conditions as in Example 1 were employed.

Other control conditions at the time of winding are as follows. The tension applied to the polymer film 15 was set to 100 N/film width, the film traveling speed was set to 60 m/min, and the diameter of the core 23 was set to 169 mm, and a film was produced in the film production line 11 shown in FIG. Volume 29.

The film roll 29 formed by the above method was stored in an environment of 25 ° C and 65% RH for 30 days. Next, the film roll 29 which has passed the 30 days is placed on a coiler (not shown) to be re-wound. By the unwinding of the rewinding, the front end portion of the film wound around the winding core of the film roll 29 can be observed. Next, an evaluation test for determining the length of the kerf transfer disappearance was performed on the front end portion of the film. In the evaluation test, the front end portion of the film was placed on a stage covered with a black cloth, and then the light of the fluorescent lamp was irradiated from the upper surface. The presence or absence of nick transfer was visually evaluated by the reflected light. Then, the length at which the slit transfer in the vicinity of the winding core disappears is obtained.

Eight film rolls 29 were produced by the respective examples and comparative examples. As a result, as is clear from the following Table 1, it was confirmed that the slits were changed in Examples 1 to 6 as compared with those of Comparative Examples 1 and 2. Printing, the length L3 of the core portion which is problematic in the practical application of the slit transfer is reduced to less than 1/10 to 1/2, and it is understood that the slit transfer is improved. In addition, the level of problems in the practical application of the slit transfer is based on a limit sample (a sample indicating the quality limit of a good or defective product). Further, in the third embodiment in which the cutting line at the tip end of the film is inclined at an inclination angle θ 1 of 16° with respect to the film width direction reference line BL1, the evaluation result of Example 1 which is the same as the other conditions is longer than 10 m. To 40m. Further, in Examples 4 to 6 in which the inclination angle θ 1 was increased to 20°, 25°, and 30°, respectively, it was found that the longer the inclination angle θ 1 is, the longer the length L3 is, and the closer the inclination angle θ 1 is to 0°. The better.

In addition, the evaluation "A" in Table 1 means that the film length L3 was less than 10 m when the slit transfer from the core portion was confirmed, and the evaluation result of the slit transfer was good. "B" means that the length L3 is 10 m or more and less than 40 m, and the slit transfer is slightly shallow, but the evaluation result is substantially good. "C" means that the length L3 is 40 m or more and less than 60 m, and although there is a generation of slit transfer, there is no problem in practical use. A, B, and C are qualified. "D" means that the length L3 is 60 m or more, and the product loss is largely unqualified.

15‧‧‧ polymer film

15a‧‧‧Film front end

15b‧‧‧Front end of film

23‧‧‧Volume core

31‧‧‧Joint tape

31a‧‧‧Support

31b‧‧‧core side adhesive layer

31c‧‧‧film side adhesive layer

32‧‧‧Blank Department

Claims (13)

A mesh roll obtained by winding a belt-shaped mesh, comprising: a winding core to be wound around the mesh; and a mesh wound around an outer circumferential surface of the winding core; The joining member fixes the front end portion of the mesh to the outer peripheral surface; the support member is provided on the joining member; the core side adhesive layer is provided on the joining member and adhered to the winding core, and the core side adhesive layer a surface formed on one of the support members; and a mesh-side adhesive layer provided on the bonding member and fixed to the winding core by adhering to the front end portion, the mesh side adhesive layer The other end surface of the support body is formed by coating the mesh side adhesive layer in a state in which the blank portion of the mesh-side adhesive layer is exposed. The mesh roll according to claim 1, wherein the blank portion is provided with a cushioning material. The mesh roll according to claim 2, wherein the cushioning material is formed to be thicker than the mesh and is composed of an elastic member, and the elastic member is taken up to the aforementioned roll by the mesh The core is deformed to a thickness smaller than the aforementioned mesh. The web roll according to any one of the preceding claims, wherein the front end of the web is cut at an inclination angle θ 1 with respect to a width direction of the web at - In the range of 30° < θ 1 < 30°, the joining member is attached to the winding core in parallel with the front end of the mesh. The mesh roll according to any one of the preceding claims, wherein the mesh is an optical film. The web roll of claim 4, wherein the web is an optical film. The mesh roll according to claim 5, wherein the optical film is cut into a sheet shape to form an optical sheet. The mesh roll according to claim 6, wherein the optical film is cut into a sheet shape to form an optical sheet. A method of manufacturing a web roll, which is obtained by winding a strip-shaped web onto a core to produce a web roll, characterized by comprising the steps of: (A) attaching a joint member to a core, wherein the joint The member includes a support, a first adhesive layer, and a second adhesive layer, wherein the support has a strip shape, and the first adhesive layer is formed on one surface of the support and adheres to the winding core, and the second adhesive layer is formed. The other surface of the support body; (B) the core of the bonding member to which the bonding member is attached is placed at the web winding position; (C) the front end portion of the mesh is fixed to the front portion via the bonding member a winding core in which the exposed portion is provided on the second adhesive layer by covering a portion of the second adhesive layer with the front end portion; and (D) the mesh is formed by rotating the winding core The material is taken up to the aforementioned core. The method of manufacturing a web roll according to claim 9, wherein the blank portion is provided with a cushioning material that is elastically deformed. The method of manufacturing a web roll according to claim 10, wherein the cushioning material is formed to be thicker than the web and is composed of an elastic member which is taken up by the web The core is deformed to have a thickness smaller than the aforementioned mesh. The method for producing a web roll according to any one of the items 9 to 11, wherein the front end of the web is cut at an inclination angle θ with respect to a width direction of the web. 1 In the range of -30 ° < θ 1 < 30 °, in the step A, the joining member is attached to the outer peripheral surface of the winding core in parallel with the front end of the mesh. A method of producing an optical sheet, comprising: (E) attaching a bonding member to a winding core, wherein the bonding member includes a support, a first adhesive layer, and a second adhesive layer, and the support is a tape The first adhesive layer is formed on one surface of the support and adhered to the winding core, and the second adhesive layer is formed on the other surface of the support; (F) the joint member is attached The winding core is set at the winding position; (G) the front end portion of the optical film is fixed to the winding core via the bonding member, wherein the front end portion covers a part of the second adhesive layer in the foregoing The second adhesive layer is provided with a blank portion exposed; (H) winding the optical film onto the winding core by rotating the winding core; (I) extracting the optical film wound from the winding core; and (J) the optical fiber extracted from the winding core The film was cut into a sheet to form an optical sheet.