JP7340653B1 - Manufacturing method of sheet film - Google Patents

Abstract

An object of the present invention is to prevent stringing of an adhesive when pulling out and removing unnecessary portions after cutting an original fabric having a first film, an adhesive layer, and a second film. [Solution] A long strip-shaped raw fabric 1 having a first film, an adhesive layer, and a second film is conveyed to the downstream side in the longitudinal direction, and the raw fabric 1 is cut with a cutting blade 51 into a plurality of sheets. In the method for obtaining the film 2, the original fabric 1 is cut into a plurality of sheet films 2 and an unnecessary portion 3 remaining in the shape of a mesh in plan view remaining around each sheet film 2, Immediately after the cutting, the unnecessary portion 3 is pulled out and removed. [Selection diagram] Figure 12

Description

The present invention relates to a method for cutting an original film including an adhesive layer to produce a plurality of sheet films.

Conventionally, products having an adhesive layer between two films have been used for various purposes.
For example, an optical film having an adhesive layer is formed into a predetermined planar shape that matches the screen of an image display device or the like, and is incorporated into the screen of the image display device or the like. In this specification, a film formed into a predetermined shape is referred to as a "sheet film."
The sheet film is generally obtained by cutting out a long strip-shaped original fabric having film/adhesive layer/film. The cut out sheet film can be used as a product as it is, or can be further subjected to arbitrary cutting processing and the like before being used as a product.
For example, in Patent Document 1, an original optical film having an optical film, an adhesive layer, and a separator film (release liner) is cut, and a plurality of vertical lines extending in the longitudinal direction are cut in the plane of the original optical film. a step of dividing the film product into a cut residual portion having a band and a plurality of horizontal bands extending in the transverse direction, and the film product surrounded by the vertical band and the horizontal band; a step of separating the cut residue from the film product by pulling out the cut residue and removing the cut residue, holding the film product so that it does not lift up and without pressing vertical bands of the cut residue; A method of manufacturing a film product is disclosed in which the cut residue is pulled out and removed.

According to the method of Patent Document 1, the film product does not follow the cut residue when the cut residue is pulled out, and the cut residue can be reliably separated and removed from the film product.

Japanese Patent Application Publication No. 2021-164984

By the way, when an original fabric in which an adhesive layer is provided between two films is cut, two cut end surfaces generated at the cutting line face each other. Therefore, there is a risk that the adhesive of the adhesive layer may adhere to the cut end surface. If adhesive adheres after cutting, when the cut remaining part (unnecessary part) is pulled out, the adhered adhesive will be stretched like a thread and then torn off. For this reason, the adhesive stretched like a thread may adhere to the surface of the sheet film, and the sheet film and its surroundings may be stained with the adhesive.

An object of the present invention is to provide a method for producing a sheet film that can prevent stringing of the adhesive when removing unnecessary parts after cutting a raw film having a first film, an adhesive layer, and a second film. The goal is to provide the following.

In the present invention, a long strip-shaped original fabric having a first film, an adhesive layer, and a second film is transported downstream in the longitudinal direction, and the original fabric is cut with a cutting blade to obtain a plurality of sheet films. In the method, the adhesive of the adhesive layer has a storage elastic modulus G' at 25° C. of 0.001 MPa or more and 1 MPa or less, and the original fabric is placed between a plurality of sheet films and a periphery of each sheet film. The unnecessary portions remaining in the planar view mesh shape are cut into sections, and the unnecessary portions are pulled out and removed while the adhesive of the adhesive layer is not attached to the cut end surface resulting from the cutting.

In a preferred manufacturing method of the present invention, the unnecessary portions are pulled out and removed before the plurality of sheet films and the original fabric divided into unnecessary portions are transported within 300 cm from the cutting position on the most downstream side.
In a preferred manufacturing method of the present invention, the first film of the original fabric includes a polarizing film.

According to the manufacturing method of the present invention , it is possible to prevent the adhesive from becoming stringy when an unnecessary portion is pulled out. Therefore, according to the present invention, it is possible to prevent the sheet film and its surroundings from being soiled by the adhesive.

A plan view of the original fabric. A plan view of a sheet film. FIG. 3 is a side view showing an example of one layer structure of the original fabric. FIG. 7 is a side view showing another example of the layer structure of the raw fabric. FIG. 1 is a schematic plan view of a sheet film manufacturing apparatus. FIG. 1 is a schematic side view of a sheet film manufacturing apparatus. An enlarged perspective view of a cutting blade. FIG. 2 is a plan view of the original film divided into sheet films and unnecessary parts. FIG. 7 is an enlarged front view seen from the direction of arrow IX in FIG. 6; FIG. 6 is an enlarged cross-sectional view taken along line XX in FIG. 5. FIG. 3 is an enlarged cross-sectional view showing a state when the original fabric is cut with a cutting blade. FIG. 2 is an enlarged cross-sectional view showing a state when unnecessary portions are removed from the original fabric divided into unnecessary portions and sheet films. A reference diagram explaining the principle of adhesive stringiness. The schematic side view of the manufacturing device of a 1st modification. The schematic side view of the manufacturing device of a 2nd modification.

In this specification, "planar view" refers to the view from a direction perpendicular to the surface of the object, and "planar shape" and "plan view" refer to the view from the perpendicular direction to the surface of the object. Refers to the shape and drawing of the object at the time.
Furthermore, in this specification, the expression "substantially" means to include the range permitted in the technical field of the present invention. Furthermore, in this specification, when a plurality of numerical ranges expressed as "more than or equal to the lower limit and less than or equal to the upper limit" are separately described, any lower limit value and any upper limit value can be selected.

[Sheet film manufacturing equipment]
5 and 6 show an apparatus A for manufacturing sheet film 2. FIG.
Referring to FIGS. 5 and 6, the manufacturing apparatus A includes a transport section B that transports the original film 1 and sheet films 2, and a transport section B that transports the original film 1 and a plurality of sheet films 2 and unnecessary portions that are mesh-like in plan view. 3, a removing section D that removes the unnecessary portion 3, and an accumulating section E.

<Original fabric>
The manufacturing apparatus A of the present invention cuts a long strip-shaped original film 1 in the plane, removes an unnecessary portion 3, and obtains a sheet film 2.
The original fabric 1 is usually in the form of a long strip as shown in FIG. However, in FIG. 1, one longitudinal side of the long strip-shaped original fabric 1 is omitted. The original fabric 1 is wound into a roll and is set in the unwinding section 41 of the original fabric feeding section. Here, in this specification, the long strip shape refers to a substantially rectangular shape in a plan view where the length in the longitudinal direction is sufficiently longer than the length in the transverse direction. The length of the raw fabric 1 in the longitudinal direction is, for example, 5 m or more, preferably 10 m or more. Note that the lateral direction is a direction perpendicular to the longitudinal direction.

As shown in FIG. 2, the sheet film 2 obtained from the original film 1 is formed into a predetermined shape in plan view. That is, the sheet film 2 is a film formed into a predetermined shape from the original film 1. FIG. 2 shows a sheet-shaped film 2 having a substantially rectangular shape in plan view. The shape of the sheet film 2 in plan view is not particularly limited. For example, the shape of the sheet film 2 in plan view may be a substantially rectangular shape (the substantially rectangular shape is a substantially rectangular shape or a substantially square shape), a substantially polygonal shape such as a substantially triangular shape, a substantially hexagonal shape, a substantially circular shape, or a substantially elliptical shape. , a combination of these shapes, or an arbitrary irregular shape. "About" in the words "approximately rectangular," "approximately triangular," and "approximately polygonal" refers to, for example, a shape with chamfered corners, a shape with a portion of the sides slightly bulging or recessed, and a shape with slightly curved sides. etc. are included. Further, the term "approximately" in the substantially circular shape and the substantially elliptical shape includes, for example, a shape in which a portion of the circumference is slightly bulged or depressed, a shape in which a portion of the circumference is slightly straight or obliquely lined, and the like.

The sheet film 2 becomes a final product or an intermediate for a product. The product intermediate is in the process of producing a product, and the product can be obtained by further subjecting the intermediate to appropriate processing such as cutting and/or surface treatment.
The use of the product is not particularly limited. Products obtained from the sheet film 2 include, for example, optical parts or mechanical parts to be incorporated into the screen of an image display device or the lens of sunglasses; sealing materials such as tack labels; packaging materials such as wrapping films; and electromagnetic shielding. Electrical parts; etc. In particular, since high cleanliness is required, it is preferable to apply the method of the present invention to form products for use in optical components.

In terms of layer structure, the original fabric 1 includes a first film, a second film, and an adhesive layer provided between the first film and the second film. The layer structure of the sheet film 2 is also the same as that of the original fabric 1, and the sheet film 2 also has a first film, a second film, and an adhesive provided between the first film and the second film. and an agent layer. Since the layer structure of the sheet film 2 is the same as that of the raw film 1, the layer structure of the raw film 1 will be explained, and the explanation of the layer structure of the sheet film 2 will be omitted.
The original fabric 1 may further include another film or layer, provided that it has a laminated structure of first film/adhesive layer/second film.

Hereinafter, some examples of layer configurations of the raw fabric 1 for use in optical components will be exemplified.
FIG. 3 is a side view showing one example of the layer structure of the raw fabric 1, and FIG. 4 is a side view showing another example of the layer structure of the raw fabric 1.
The original fabric 1 shown in FIG. 3 includes, in order from the front side, a first film 11, an adhesive layer 15, and a second film 12. Around the original fabric 1, each end surface 11a, 12a of the first film 11 and the second film 12 and the end surface 15a of the adhesive layer 15 extend in parallel. In other words, the end surface 11a of the first film 11, the end surface 15a of the adhesive layer 15, and the end surface 12a of the second film 12 continuously form one plane. Therefore, the end surface of the original fabric 1 is composed of a set of end surfaces 11a, 15a, and 12a of the first film 11, the adhesive layer 15, and the second film 12. Note that in this specification, an end surface is a surface along the thickness direction, and a front surface and a back surface are surfaces perpendicular to the thickness direction.
The original fabric 1 shown in FIG. 4 includes, in order from the front side, a third film 13, a first adhesive layer 151, a first film 11, a second adhesive layer 152, and a second film 12. has. Around the raw fabric 1, each end surface 11a, 12a, 13a of the first to third films 11, 12, 13 and each end surface 151a, 152a of the first and second adhesive layer 151, 152 are parallel to each other. Extending. In other words, the end surfaces 11a, 12a, 13a of each film 11, 12, 13 and each end surface 151a, 152a of each adhesive layer 151, 152 continuously form one plane.
Although not shown, the original fabric 1 may further include other films and/or adhesive layers. Regarding the original fabric 1 having the other film and/or adhesive layer, the end face of each film and the end face of each adhesive layer continuously form one plane.

The raw material 1 for use in optical components includes an optical film. In this case, all the films such as the first film 11 may be optical films, or at least one film selected from the plurality of films may be an optical film and at least one film may be a film other than an optical film. It's okay.
In the layer structure shown in FIG. 3, for example, the first film 11 is an optical film, and the second film 12 is a release liner (a film other than the optical film), and in the layer structure shown in FIG. Film 11 and third film 13 are optical films, and second film 12 is a release liner. In FIG. 3, for example, an optical function film, which will be described later, is used as the first film 11. In FIG. 4, for example, an optical function film, which will be described later, is used as the first film 11, and a protective film, which will be described later, is used as the third film 13. The release liner is releasably adhered to the adhesive layer 15, 152. Therefore, the release liner and the adhesive layer 15, 152 can be peeled off at their interface, but the optical film and the adhesive layer 15, 152 are difficult to peel off. In use, the release liner is removed by peeling it off. In addition, when the third film 13 in FIG. 4 is a protective film, the third film 13 may be peeled off from the first film 11 together with the adhesive layer 151, or the third film 13 may be peeled off from the first film 11 together with the adhesive layer 151. 1 film 11 through an adhesive layer 151 in a state where it is difficult to peel off.

Examples of the optical film include optical functional films and protective films. The optical film may have a single layer structure, or may have a multilayer structure of two or more layers. When the optical film has a multilayer structure of two or more layers, it may be a laminate in which two or more films having the same function are laminated, or it may be a laminate in which two or more films having different functions are laminated. Examples of the laminate of films having different functions include a laminate of a polarizing film and a retardation film, a laminate of a polarizing film and a protective film, and the like.
Examples of the optically functional film include a polarizing film, a retardation film, a light diffusion film, a brightness enhancement film, an antiglare film, and a light reflection film. A polarizing film is a film that has the property of transmitting light (polarized light) vibrating in one specific direction and blocking light vibrating in other directions. The retardation film is a film that exhibits optical anisotropy, and typically includes stretched films of acrylic resin, cycloolefin resin, cellulose resin, and the like. Moreover, the protective film is a film used for the purpose of protecting the optical function film. A colorless and transparent film is typically used as the protective film.
The thickness of the optical film is not particularly limited, and is, for example, 5 μm or more and 300 μm or less.

The release liner has a release surface with excellent releasability from the adhesive layer.
Examples of the release liner include resin films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films; paper; porous films such as woven fabrics, nonwoven fabrics, and net fabrics; and foamed resin films. The release liner is preferably a resin film because it has excellent surface smoothness. Examples of the resin film include polyethylene terephthalate film, polybutylene terephthalate film, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyurethane film, and ethylene. -Vinyl acetate copolymer film, etc.
The thickness of the release liner is not particularly limited, and is, for example, 5 μm or more and 200 μm or less, preferably 10 μm or more and 100 μm or less.

The adhesive layer has adhesiveness at room temperature, maintains adhesiveness even after peeling off, and can be reapplied. The adhesive layer is made of a known adhesive. The adhesives include colorless and transparent acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, and cellulose adhesives. Examples include adhesives.
In particular, it is effective to apply the method of the present invention to the original fabric 1 having an adhesive layer formed of a relatively soft adhesive.
The hardness of the adhesive can be indexed, for example, by the storage modulus G'. The soft adhesive has, for example, a storage modulus G' at 25° C. of 0.001 MPa or more and 1 MPa or less, preferably 0.01 MPa or more and 1 MPa or less. The storage modulus can be measured by dynamic viscoelasticity measurement. Specifically, the adhesive layer was heated at a temperature of -20 to 100°C at a frequency of 1 Hz using a dynamic viscoelasticity measurement device (device name "ARES" manufactured by TA Instruments). The storage modulus G' at 25° C. can be calculated by measuring at a heating rate of 5° C./min.
The thickness of the adhesive layer is not particularly limited, but is, for example, 0.1 μm or more and 50 μm or less, preferably 1 μm or more and 30 μm or less.

<Transport section>
Referring to FIGS. 5 and 6, the transport unit B of the manufacturing apparatus A includes a web feed unit that transports the web 1, and at least one web transport unit that transports the web 1 before and after cutting and a plurality of sheet films 2. and a conveyor belt. The original fabric feeding unit includes an unwinding unit 41 loaded with the original fabric 1 wound on a roll, a guide roller 42 that guides the original fabric 1, and a drive device (not shown). The original fabric feeding unit unwinds the original fabric 1 from the unwinding unit 41 and conveys the original fabric 1 from the upstream side to the downstream side in the longitudinal direction. In addition, the longitudinal direction and the conveyance direction of the original fabric 1 are the same direction, and the lateral direction and the width direction of the original fabric 1 are the same direction.
Moreover, the first conveyor belt 43 carries the original fabric 1 before and after cutting. A cutting section C is disposed above the first conveyor belt 43, and a removing section D is disposed immediately downstream of the cutting section C. The second conveyor belt 44 carries a plurality of sheet films 2 and conveys them. On the downstream side of the second conveyor belt 44, a stacking section E for collecting sheet films 2 is arranged. Note that a bridging plate 45 is provided between the end of the first conveyor belt 43 and the end of the second conveyor belt 44.

<Cutting processing section>
Referring to FIGS. 5 and 6, the cutting section C includes a cutter device. The cutter device includes a cutting blade 51 and a base plate 52.
Further, a pedestal 53 is provided opposite the cutting blade 51. The pedestal 53 is made of, for example, a steel plate with excellent strength. The pedestal 53 is fixed to a frame (not shown) of the manufacturing apparatus A or the like. The pedestal 53 is arranged on the back side of the first conveyor belt 43. The first conveyor belt 43 not only functions to convey the original fabric 1 before and after cutting, but also functions as a blade receiving member. The blade receiving member means a member that receives the cutting edge of the cutting blade 51. When cutting the original web 1, the cutting edge of the cutting blade 51 that comes out on the back side of the original web 1 bites into the first conveyor belt 43, so that the original web 1 can be reliably cut and the cutting edge of the cutting blade 51 is not deteriorated. This can be prevented. The first conveyor belt 43, which also functions as such a blade receiving member, is flexible enough to receive the cutting edge of the cutting blade 51, and has sufficient strength and thickness to prevent breakage even if the cutting edge enters. A sheet having the following properties is used. For example, as the first conveyor belt 43, a synthetic resin sheet, a rubber sheet, a nonwoven fabric, etc. can be used.
Note that, as disclosed in Patent Document 1 (Japanese Unexamined Patent Publication No. 2021-164984), a blade receiving sheet independent of the conveyor belt may be provided separately.

The cutting blade 51 is provided on a base plate 52. The base plate 52 has a flat shape, and the cutting blade 51 is fixedly provided on the base plate 52. The cutter device (cutting blade 51) is moved in a direction perpendicular to the surface of the web 1 and withdrawn by a drive device (not shown). The illustrated cutter device moves up and down. The cutter device is a punching type cutter that punches out the original fabric 1 by descending and leaves the original fabric 1 by ascending. As such a cutter device, a Thomson blade can typically be used.
Note that the cutter device is not limited to the punching method, and for example, a rotary die may be used (not shown). Further, the cutter device may be any device that can cut the original fabric 1 in the thickness direction, and is not limited to the punching method described above or a rotary type such as a rotary die.

FIG. 7 is an enlarged perspective view of the cutter device including the cutting blade 51. It should be noted that the cutter device of FIG. 7 is a perspective view of the cutter device of FIG. 6 viewed from below, and that the upper side of the paper in FIG. 7 corresponds to the lower side of the paper in FIG. Further, FIG. 7 also includes an enlarged view partially showing the three-dimensional shape of the cutting blade 51.
In FIG. 7, a cutting blade 51 is provided protruding from the surface of a base plate 52. As shown in FIG. Generally, one base plate 52 is provided with a plurality of cutting blades 51 in order to punch out a plurality of sheet films 2 at the same time by one downward movement. Each of the cutting blades 51 has an endless annular shape in a plan view, and is provided at regular intervals in the conveying direction and width direction of the web 1.
In the illustrated example, two rows of cutting blades 51 are arranged in the transport direction of the original fabric 1 and four rows in the width direction, but the number of cutting blades 51 is not limited to this. Further, the shape of the cutting blade 51 in plan view is not limited to the substantially rectangular shape shown in the illustrated example, but is set depending on the shape of the sheet film 2 to be formed.
The angle α of the cutting edge 51a of the cutting blade 51 is not particularly limited, and is, for example, 10 degrees or more and 100 degrees or less, preferably 20 degrees or more and 90 degrees or less. By setting the angle α of the blade edge 51a within the above range, it is possible to prevent the adhesive from adhering again to the unnecessary portion 3 and the cut end surface of the sheet film 2.

In the cutting section C, by pressing the cutting blade 51 of the cutter device against the raw fabric 1 from the surface side of the raw fabric 1, a cut having the same shape as the cutting blade 51 in plan view is made in the plane of the raw fabric 1. A line appears. The inner part surrounded by this cutting line becomes the sheet film 2, and the outer part of the cutting line becomes the unnecessary part 3.
FIG. 8 is a plan view showing the original film 1 divided into the sheet film 2 and the unnecessary portion 3. As shown in FIG. In order to easily distinguish between the sheet film 2 and the unnecessary portion 3, the unnecessary portion 3 is marked with numerous dots.
As shown in FIG. 8, the surface of the cut original fabric 1 is divided into a plurality of sheet films 2 and an unnecessary portion 3 having a mesh shape in plan view.
The unnecessary portion 3 is composed of a plurality of vertical bands 3a extending in a band shape in the conveyance direction and a plurality of horizontal bands 3b extending in a band shape in the width direction. The unnecessary portion 3 consisting of such vertical bands 3a and horizontal bands 3b has a lattice shape in plan view. Note that the unnecessary portion 3 is not limited to a lattice shape in a plan view, but may have a diagonal lattice shape, for example, as long as it has a mesh shape in a plan view.

<Removal part>
The removing section D removes the unnecessary portion 3 remaining around the sheet film 2 (the section surrounded by the cutting line) formed within the plane of the original fabric 1 in the cutting section C.
FIG. 9 is an enlarged front view of the removing section D viewed from the downstream side in the conveying direction, and FIG. 10 is an enlarged sectional view of the cutting section C and the removing section D cut along the conveying direction.
5, FIG. 6, FIG. 9, and FIG. 10, the removing section D includes a separation member 61 for separating the unnecessary portion 3 from the sheet film 2, and a collection roller for winding up the unnecessary portion 3. 62, and further includes a guide roller 63 if necessary.
The separation member 61 is made of a rod-shaped body extending in the width direction of the original fabric 1, and is made of, for example, a cylindrical body. Note that as the separation member 61, the separation member disclosed in Patent Document 1 and having a pressing portion and a non-pressing portion may be used.

The separation member 61 is arranged so as to be in contact with the surface of the original fabric 1 divided into the unnecessary portion 3 and the sheet film 2. In the cutting section C, the original web 1 is divided into an unnecessary portion 3 and a sheet film 2, and then transported to a removing section D by a first conveyor belt 43.
Specifically, the original film 1 divided into a plurality of sheet films 2 and unnecessary portions 3 is conveyed downstream on the first conveyor belt 43 . A separating member 61 is arranged so as to be in contact with the original fabric 1 during transportation.
By pulling out the unnecessary portion 3 along the circumferential surface of the separating member 61, the unnecessary portion 3 is separated from the sheet film 2 adjacent to the cutting line. Hereinafter, the point where the unnecessary portion 3 and the sheet film 2 separate when the unnecessary portion 3 is pulled out will be referred to as a "separation point."
The unnecessary portion 3 is generated by cutting the original fabric 1 with a cutter device. According to the findings of the present inventors, stringing of the adhesive can be prevented by removing the unnecessary portion 3 as soon as possible after cutting the original fabric 1. Therefore, it is preferable to arrange the separation member 61 so that the separation point is within 300 cm from the most downstream cutting position, and further, such that the separation point is within 250 cm from the most downstream cutting position. , it is more preferable to arrange the separation member 61. As shown in FIG. 10, the cutting position on the most downstream side is the most downstream side (the downstream side means the downstream side in the conveying direction of the web 1) when the cutting blade 51 cuts the web 1. Refers to a certain cutting position. In FIG. 10, the distance from the most downstream cutting position to the separation point is indicated by the symbol L1.
Note that the time from when the original fabric 1 is cut to when the unnecessary portion 3 is pulled out can be determined from the distance L1 and the transport speed of the original fabric 1.

<Accumulation section>
The stacking section E collects the sheet films 2 obtained by removing the unnecessary portions 3 in the removing section D.
For example, a container 71 is arranged in the stacking section E, and the sheet films 2 conveyed by the second conveyor belt 44 are sequentially accommodated in the container 71.
The sheets of film 2 accumulated in the container 71 are cut and/or subjected to any appropriate processing as necessary to obtain a product.

[Method for producing sheet film]
In the method for producing a sheet film 2 of the present invention, a long strip-shaped original fabric 1 having a first film, an adhesive layer, and a second film is conveyed to the downstream side in the longitudinal direction, and the original fabric 1 is transferred to a plurality of layers. The film is cut so as to be divided into a sheet film 2 and an unnecessary portion 3 remaining around each sheet film 2 and having a mesh shape in a plan view. The present invention is characterized in that immediately after cutting the original fabric 1, the unnecessary portion 3 is pulled out and removed.

As shown in FIG. 10, the base plate 52 above the original fabric 1 is lowered, and the original fabric 1 is cut with the cutting blade 51 (see FIG. 11).
Next, as shown in FIG. 12, the base plate 52 is raised and the cutting blade 51 is extracted from the original fabric 1. The original fabric 1 cut by the cutting blade 51 is divided into a plurality of sheet films 2 and an unnecessary portion 3 having a mesh shape in plan view. The raw film 1 divided into the sheet film 2 and the unnecessary portion 3 is conveyed downstream by the first conveyor belt 43, and the unnecessary portion 3 is pulled out and removed by the separation member 61. The drawn out unnecessary portion 3 is wound up on a collection roller 62. The unnecessary portion 3 is drawn out immediately after the original fabric 1 is cut. For example, by arranging the separating member 61 in the <Cutting section> column above, the original film 1 divided into the sheet film 2 and the unnecessary portion 3 can be cut within 300 cm (preferably within 250 cm) from the cutting position on the most downstream side. It is preferable to pull out the unnecessary portion 3 before transporting it to the next location.
The unnecessary portion 3 is pulled out in synchronization with the conveyance of the original fabric 1. Therefore, the withdrawal speed of the unnecessary portion 3 and the conveyance speed of the original fabric 1 are the same. For example, the conveyance speed of the original fabric 1 is 1 m/min or more, preferably 2 m/min or more. Note that there is no particular upper limit to the conveyance speed of the original fabric 1, as it is preferable to be as fast as possible from the perspective of preventing the adhesive from re-adhering to the cut end surface. An upper limit is set.

When a punching type cutter device is used as in this embodiment, the original fabric 1 is conveyed by a length approximately corresponding to the range to be cut by one lowering of the cutter device. For example, when two sheets of film 2 are formed between the horizontal strips 3b (part of the unnecessary portion 3) by one lowering of the cutter device, the film is transported by a length approximately corresponding to the two sheets of film 2. As shown in FIG. 12, this one-time conveyance length L2 is, as shown in FIG. It is equal to the length of the sheet film 2 in the transport direction.
After conveying the original fabric 1 for the one-time conveyance length and pulling out the unnecessary portion 3, if the conveyance of the original fabric 1 and the extraction of the unnecessary portion 3 are temporarily stopped, a state as shown in FIG. 10 occurs. Become.
Afterwards, the steps of lowering the cutter device shown in FIG. 11, transporting the cut original fabric 1 and pulling out and removing the unnecessary portion 3 shown in FIG. 12, and temporarily stopping the transport and pulling are repeated as one cycle.
The plurality of sheet films 2 remaining after removing the unnecessary portions 3 are conveyed downstream by the second conveyor belt 44. The second conveyor belt 44 may repeatedly transport and temporarily stop the sheet film 2 in synchronization with the transport of the original film 1, or may continuously transport the sheet film 2 without stopping. It's okay.

As in the present invention, by removing unnecessary portions 3 immediately after cutting the original fabric 1, stringing of the adhesive can be prevented.
Specifically, when the original fabric 1 is cut and divided into an unnecessary portion 3 and a sheet film 2, as shown in FIG. 13(a), the cut end surface 3X of the unnecessary portion 3 and the cutting of the sheet film 2 The end surfaces 2X are in a state facing each other. When the raw fabric 1 in this state is conveyed by a conveyor belt or the like, the adhesive swells due to the vibration of the device, and as shown in FIG. The cut end surface 21X of the adhesive layer 21 of the film 2 may adhere. When the unnecessary portion 3 is pulled out with the adhesive adhered in this manner, the adhesive Y is stretched like a thread (so-called adhesive stringing), as shown in FIG. 3(c). The stringy adhesive Y is then torn into pieces. The torn thread-like adhesive adheres to the surface of the sheet film 2, the cut end surface, or the surface of the conveyor belt. In particular, in the case of an adhesive layer made of the above-mentioned soft adhesive, adhesion of the adhesive on the cut end surface is likely to occur.

In this regard, if the unnecessary portion 3 is removed immediately after cutting the original fabric 1 as in the present invention, the adhesive is difficult to adhere to the cut end surface of the unnecessary portion 3 and the cut end surface of the sheet film 2, and the adhesive is Can prevent stringing. That is, in the present invention, since the unnecessary portion 3 is pulled out while the adhesive is not attached to the cut end surface (that is, immediately after cutting), it is possible to prevent the adhesive from becoming stringy. Therefore, according to the method of the present invention, it is possible to prevent the adhesive from adhering to the sheet film 2 and its surroundings and causing them to become dirty.

[Modified example]
In the cutting processing section C of the above embodiment, a punching type cutter device is illustrated, but a rotary type cutter device may be used, for example, as shown in FIG. 14.
In the case of a rotary cutter device, the web 1 is cut at a location where the peripheral surface of a rotary die 55 having a cutting blade 54 and the web 1 are in contact with each other. Therefore, when a rotary cutter device is used, the cutting position S2 on the most downstream side is a contact point where the circumferential surface of the rotating rotary die 55 and the web 1 come into contact. Further, in the case of a rotary cutter device, the original fabric 1 is transported at a constant speed without stopping, and in synchronization with this, the unnecessary portion 3 is also pulled out at the same speed.

In the above embodiment, the unnecessary portion 3 is pulled out upward and wound up, but, for example, as shown in FIG. 15, the unnecessary portion 3 may be pulled out downward and wound up on the collection roller 62.
When pulling out the unnecessary part 3 downward, for example, as shown in FIG. 15, the unnecessary part 3 can also be reversed using the circumferential surface of the conveyor belt.

1 Original film 11 First film 15,151,152 Adhesive layer 12 Second film 2 Sheet film 3 Unnecessary part S1 Separation point S2 Most downstream cutting position

Claims (3)

A method for obtaining a plurality of sheet films by transporting a long strip-shaped original fabric having a first film, an adhesive layer, and a second film to the downstream side in the longitudinal direction, and cutting the original fabric with a cutting blade,
The adhesive of the adhesive layer has a storage modulus G' at 25° C. of 0.001 MPa or more and 1 MPa or less,
Cutting the original film into a plurality of sheet films and an unnecessary portion remaining in a mesh shape in a plan view around each sheet film,
Pulling out and removing the unnecessary portion while the adhesive of the adhesive layer is not attached to the cut end surface generated by the cutting ,
Method for producing sheet film. The sheet-fed film according to claim 1, wherein the unnecessary portion is pulled out and removed before the original fabric divided into the plurality of sheet-fed films and unnecessary portions is conveyed within 300 cm from the cutting position on the most downstream side. manufacturing method. The method for manufacturing a sheet film according to claim 1 or 2, wherein the first film of the original film includes a polarizing film.

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