JP2019107764A - Method for manufacturing sheet film - Google Patents

Abstract

An object of the present invention is to provide a method for manufacturing a single-wafer film, which can suppress generation of minute streaks. In a cutting step of cutting a multilayer film having an adhesive layer to obtain a single-sheet film, a cutting blade member is moved from a first surface to a second surface of the multilayer film. And a speed V (μm / sec) of the pressing / cutting blade member 21 on the first surface 101 of the multilayer film 10 is set to one of the pressure-sensitive adhesive layers. A method for manufacturing a single-wafer film, wherein the following pressure-sensitive adhesive layer satisfies the following relational expression (1) when one pressure-sensitive adhesive layer is used as a reference pressure-sensitive adhesive layer. t / V <1 / ω1 (1) [In the above relational expression (1), t represents the thickness (μm) of the multilayer film, and ω1 is the dynamic viscoelasticity measurement by frequency sweep of the reference pressure-sensitive adhesive layer at a temperature of 20 ° C. Represents a frequency (1 / sec) at which the storage elastic modulus calculated based on the measured value of (a) is 3.0 × 105 (Pa). [Selection] Fig. 4

Description

  The present invention relates to a method for producing a sheet film from a multilayer film having a pressure-sensitive adhesive layer, and also relates to an apparatus for producing the multilayer film and a method for cutting the multilayer film.

  Conventionally, as a method of cutting a multilayer film including a polarizing plate and the like, a method of cutting using a press-cutting blade is known (for example, JP-A-2015-33727 (Patent Document 1)). Patent Document 1 describes that generation of fluff on the cut surface can be suppressed by using a pressing / cutting blade having a surface roughness of a cutting edge within a specific numerical range as a pressing / cutting blade used for cutting a multilayer film. There is.

JP, 2015-33727, A

  As described in Patent Document 1, when the multilayer film is cut using a press-cutting blade, there may be a case where minute streaky unevenness is generated in the vicinity of a cut portion on the surface of the multilayer film. When manufacturing a sheet-fed film by cutting a multilayer film for a mobile device such as a smartphone, the size of the sheet-fed film is small, and the displayed characters and images are relatively small. It was easy to be seen, and even if it was minute unevenness, it was easy to be conspicuous and to be an appearance defect. The inventors of the present invention have conducted investigations and found that such streak-like minute unevenness is likely to occur when the multilayer film has a pressure-sensitive adhesive layer. Then, the present inventors have found out a method capable of suppressing such streak-like minute unevenness by repeating the earnest study, and reached the present invention.

  An object of the present invention is to provide a method and an apparatus for producing a sheet film, and a method for cutting a multilayer film, which can suppress the occurrence of streak-like minute unevenness.

  The present invention provides a method and an apparatus for producing a sheet film as described below, and a method for cutting a multilayer film.

[1] A method for producing a sheet-fed film, comprising a cutting step of obtaining a sheet-fed film from the multilayer film by cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more).
The cutting step includes a push-off step of cutting the multilayer film by advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, the cutting step.
When the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film is any one of the n pressure-sensitive adhesive layers, the pressure-sensitive adhesive layer is used as the reference pressure-sensitive adhesive layer The manufacturing method of the sheet film which satisfy | fills the following relational expression (1).

t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]
[2] The sheet according to [1], wherein the pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C. and an angular frequency of 1,000 rad / s among the pressure-sensitive adhesive layers is used as the reference pressure-sensitive adhesive layer. How to make a film.

[3] The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The method for producing a sheet film according to [1], wherein the pressure-sensitive adhesive layer under the outermost surface layer is used as the reference pressure-sensitive adhesive layer.

  [4] The method for producing a sheet film according to any one of [1] to [3], wherein the multilayer film has a polarizer.

[5] An apparatus for producing a sheet film, comprising a cutting portion for cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more) to obtain the sheet film from the multilayer film,
The cutting unit is a pressing / cutting blade disposed so as to be able to enter the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, and a control unit that controls the movement of the pressing / cutting blade And
The control unit is configured to set the velocity V (μm on the first surface of the multilayer film) of the pressing / cutting blade when one of the n pressure-sensitive adhesive layers is the reference pressure-sensitive adhesive layer. An apparatus for manufacturing a sheet-fed film, which controls (a) / sec) to satisfy the following relational expression (1).

t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]
[6] The sheet according to [5], wherein the pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C. and an angular frequency of 1,000 rad / s among the pressure-sensitive adhesive layers is used as the reference pressure-sensitive adhesive layer. Film production equipment.

[7] The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The apparatus for producing a sheet film according to [5], wherein the pressure-sensitive adhesive layer under the outermost surface layer is used as the reference pressure-sensitive adhesive layer.

  [8] The apparatus for producing a sheet film according to any one of [5] to [7], wherein the multilayer film has a polarizer.

[9] A cutting method for cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more),
Including a pushing and cutting step of advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, and cutting the multilayer film;
When the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film is one of n pressure-sensitive adhesive layers, one of the pressure-sensitive adhesive layers is used as a reference pressure-sensitive adhesive layer The cutting method of the multilayer film which satisfy | fills the following relationship (1).

t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]
[10] The multilayer film according to [9], wherein among the pressure-sensitive adhesive layers, the pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C. and an angular frequency of 1,000 rad / s is used as the reference pressure-sensitive adhesive layer. Cutting method.

[11] The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The method for cutting a multilayer film according to [9], wherein the pressure-sensitive adhesive layer under the outermost surface layer is used as the reference pressure-sensitive adhesive layer.

  [12] The method for cutting a multilayer film according to any one of [9] to [11], wherein the multilayer film has a polarizer.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method and manufacturing apparatus of a sheet film which can suppress that linear micro unevenness generate | occur | produces, and the cutting method of a multilayer film can be provided.

It is the schematic which shows typically an example of the cutting process which obtains a sheet film from a multilayer film. It is the schematic which shows typically an example of the cutting process which obtains a sheet film from a multilayer film. It is the schematic which shows typically an example of the cutting process which obtains a sheet film from a multilayer film. It is sectional drawing which shows typically the cutting device which has a press cutting blade. (A) Sectional drawing which shows an example of a press cutting blade member, (b) isometric view from a lower surface, (c) It is a bottom view. It is a figure which shows typically the cutting operation by a press cutting blade. It is a bottom view which shows an example different from FIG. 5 of a press cutting blade member. It is an image figure which shows the micro unevenness | corrugation of the stripe form which arises in the cut surface vicinity of the multilayer film surface. It is a schematic sectional drawing which shows typically an example of the specific layer constitution of a multilayer film.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In all the following drawings, the scale is appropriately adjusted and shown to facilitate understanding of each component, and the scale of each component shown in the drawings and the scale of the actual component do not necessarily coincide.

[Production method of sheet-fed film]
The method for producing a sheet film according to the present embodiment has a cutting step of obtaining a sheet film from the multilayer film by cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more). The cutting step includes a push-cutting step of advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film to cut the multilayer film.

  In the cutting process, the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film is one of the n pressure-sensitive adhesive layers, one of which is the reference adhesive layer In the case, the following relational expression (1) is satisfied.

t / V <1 / ω ₁ (1)
In the above relational expression (1), t represents the thickness (μm) of the multilayer film, and ω ₁ is the storage elastic modulus calculated based on the measurement value of the dynamic viscoelasticity measurement by frequency sweep at a temperature of 20 ° C. of the reference adhesive layer Represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa).

  When the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film satisfies the above-mentioned relational expression (1), it is suppressed that fine unevenness is generated in the reference pressure-sensitive adhesive layer in the cut-off process. As a result, it is possible to suppress the formation of streak-like minute unevenness in the vicinity of the cut surface of the surface of the multilayer film. It is preferable that it is an adhesive layer which is easy to produce a fine unevenness | corrugation in a cutting process as a reference | standard adhesive layer. The detail of the selection method of a reference | standard adhesive layer is mentioned later.

The present inventors have found that there is a correlation between the visco-elastic properties of the pressure-sensitive adhesive layer in the die-cutting process and the ease of occurrence of micro unevenness in the pressure-sensitive adhesive layer. The minute unevenness produced in the pressure-sensitive adhesive layer is a cause of the minute unevenness produced on the surface of the multilayer film. The visco-elastic property of the pressure-sensitive adhesive layer in the die-cutting process depends on the passing speed of the press-cutting blade passing through the pressure-sensitive adhesive layer. If the approximate time t / V required for the cutting edge to pass through the first surface of the multilayer film to reach the second surface, which has a correlation with the passing speed, is sufficiently short, the visco-elastic properties of the pressure-sensitive adhesive layer have appropriate characteristics. Under the assumption that micro unevenness is unlikely to occur in the pressure-sensitive adhesive layer, and as a result, micro unevenness is unlikely to occur near the cut surface of the multilayer film, the above relationship It came to find Formula (1). In addition, although the velocity V (μm / sec) is the velocity at the first surface of the multilayer film of the press-cutting blade, the velocity in the multilayer film of the pressing-cutting blade can also be controlled to be substantially the same. The time required to pass through the first surface of the multilayer film to reach the second surface can be regarded as substantially corresponding to the approximate time t / V. Usually, the approximate time t / V is less than 9.0 × 10 ⁻³ (seconds), but 2.5 × 10 ⁻³ (seconds) in order to suppress the occurrence of minute irregularities on the surface of the multilayer film. It is preferable to make it less than. Also, usually, the approximate time t / V is 1.0 × 10 ⁻⁴ (seconds) or more.

  From the viewpoint of being able to further suppress minute unevenness generated in the pressure-sensitive adhesive layer, in the punching process, the velocity V (μm / sec) of the first surface of the multilayer film of the pressing and cutting blade is any of the n pressure-sensitive adhesive layers. When one pressure-sensitive adhesive layer is used as the reference pressure-sensitive adhesive layer, it is preferable to satisfy the above-mentioned relational expression (1) and further to satisfy the following relational expression (2).

t / V <1 / ω ₂ (2)
In the above relational expression (2), t represents the thickness (μm) of the multilayer film in the same manner as the relational expression (1), and ω ₂ is a measurement of dynamic viscoelasticity measurement by frequency sweep at a temperature of 20 ° C. of the reference adhesive layer. The storage elastic modulus calculated based on the value represents a frequency (1 / second) indicating 6.0 × 10 ⁵ (Pa).

<Cutting process>
1 to 3 are each a schematic view schematically showing an example of a cutting step of cutting a multilayer film to obtain a sheet film from the multilayer film. In FIGS. 1 to 3, dotted lines indicate cutting lines in the cutting process. In the example shown in FIG. 1, the multilayer film 10b is cut into small pieces by cutting the long multilayer film 10a in a direction perpendicular to the longitudinal direction using a cutting edge having a linear cutting edge (FIG. 1A). (FIG. 1 (b)), and then the small-cut multilayer film 10b is cut in the longitudinal direction of the original multilayer film 10a using a cutting edge having a straight cutting edge (FIG. 1 (b ), To obtain a sheet film 11 of the desired size (FIG. 1 (c)).

  In the example shown in FIG. 2, the long multilayer film 10a is punched and cut with a die-cut blade (FIG. 2 (a)) to obtain the sheet film 11 of a desired size (FIG. 2 (b)). ).

  In the example shown in FIG. 3, the multilayer film 10c cut into small pieces by cutting the long multilayer film 10a in the direction orthogonal to the longitudinal direction using a cutting edge having a linear cutting edge (FIG. 3A) (FIG. 3 (b)), and then punched with a die-cut blade to obtain a sheet film 11 of a desired size (FIG. 3 (c)).

  The direction of cutting in the cutting step shown in FIGS. 1 to 3 is not particularly limited, and in the case of cutting a multilayer film having orientation characteristics, a sheet film 11 having desired orientation characteristics can be obtained. Determine the direction of cutting.

  In each of the examples shown in FIGS. 1 to 3, one or more sheet films are obtained from the multilayer film through one or more cuts. The number of cuts in the cutting step is not limited. Moreover, although the case where all the cutting | disconnection in a cutting process is a pushing-off process was demonstrated above, if it is a cutting-off process, it will not be limited if either cutting is a cutting | disconnection process, cutting by a laser beam besides a pushing-off process. It may be a cutting process including cutting by rotation of a circular blade, and the like. That is, it is sufficient that the sheet film to be obtained includes the cut surface in the punching process. According to the cut-off process, although streak-like fine unevenness tends to be generated in the vicinity of the cut portion of the surface of the multilayer film, in the present embodiment, such streak-like fine marks are generated even if all cutting is a cut-off process. Occurrence of unevenness can be suppressed.

<Closing process>
FIG. 4 is a schematic view schematically showing a cutting device having a pressing and cutting blade. By the cutting device 20 shown in FIG. 4, it is possible to carry out the push-off process according to the present embodiment. The cutting device 20 has a pressing and cutting blade member 21 having a pressing and cutting blade, a control unit 24 for controlling the vertical movement of the pressing and cutting blade member 21, and a blade receiving plate 22 provided on the upper surface. And a table 23. The multilayer film 10 is mounted on the mounting table 23 to be in contact with the blade receiving plate 22. In the multilayer film 10 mounted on the mounting table 23, the surface in contact with the blade support plate 22 is referred to as a second surface 102, and the upper surface facing the second surface 102 is referred to as a first surface 101. In the squeezing process, the squeezing blade member 21 moves downward, whereby the squeezing blade enters the multilayer film 10 from the first surface 101 to the second surface 102 of the multilayer film 10. Thereafter, the pressing and cutting blade member moves away from the multilayer film 10 by moving the pressing and cutting blade member 21 upward. The multilayer film 10 is cut by the up and down movement of the pressing and cutting blade member 21.

  FIG. 5 (a) is a cross-sectional view showing in detail a pushing / cutting blade member 21a which is an example of the pushing / cutting blade member 21 shown in FIG. FIG. 5 (b) shows a perspective view from the lower surface of the pushing and cutting blade member 21a, and the aa sectional view of FIG. 5 (b) corresponds to FIG. 5 (a). FIG.5 (c) shows the bottom view of the press cutting blade member 21a. The pressing and cutting blade member 21a includes a pressing and cutting blade 211a having a straight blade, a holding portion 213a for holding the pressing and cutting blade 211a, and an elastic body 212a disposed on the lower surface of the holding portion 213a. The lowermost surface of the elastic body 212a is located at the same position as the cutting edge portion of the pressing / cutting edge 211a or below the cutting edge portion of the pressing / cutting edge 211a.

  6 (a) to 6 (c) schematically show the cutting operation by the pushing / cutting blade 211a when the multilayer film 10 is cut by the cutting device provided with the pushing / cutting blade member 21a shown in FIGS. 5 (a) to 5 (c). FIG. In the cutting operation, the pressing / cutting blade member 21a moves downward (FIG. 6 (a)), and the lowermost surface of the elastic body 212a of the pressing / cutting blade member 21a contacts the first surface 101 of the multilayer film 10 (FIG. 6 (b) )). Thereafter, the pushing / cutting blade member 21a is further moved downward, whereby the elastic body 212a is contracted on the first surface 101 of the multilayer film 10, and only the cutting blade 211a starts from the first surface 101 of the multilayer film 10 It enters inside and continues entering until it reaches the blade backing plate 22 (FIG. 6 (c)). When the cutting blade 211 a reaches the blade receiving plate 22, the moving direction of the pressing and cutting blade member 21 is switched upward, and the cutting blade 211 a is pulled out from the multilayer film 10. The multilayer film 10 is cut in the stacking direction by the above cutting operation.

  The pressing and cutting blade 211a included in the cutting blade member 21a is not limited to the pressing and cutting blade capable of linearly cutting the multilayer film 10 as shown in FIGS. 5 (a) to 5 (c), and desired cutting is possible. Can be designed to be It may be a press-type cutting blade capable of punching out a rectangular sheet-like film from the multilayer film 10. A bottom view of an example of a press-cutting blade member provided with a die-shaped press-cutting blade is shown in FIG. A pressing / cutting blade member 21b shown in FIG. 7 includes a pressing / cutting blade 211b, a holding member, and an elastic body 212b, and has a configuration similar to that of the pressing / cutting blade member 21a shown in FIG. The multilayer film 10 can be cut by the following method.

  A Thomson blade is preferably used as the pressing and cutting blades 21a and 21b. The Thomson blade may have a resin-processed surface. The elastic bodies 212a and 212b can be shrunk on the surface of the multilayer body, and are not limited as long as the multilayer body can be fixed by sandwiching the multilayer body 10 together with the blade receiving plate 22 at the time of cutting. Porous materials such as foam and soft materials such as urethane rubber are preferably used.

  In the cutting device according to the present embodiment, the control unit 24 is located below the pressing and cutting edge member 21 so that the velocity V (μm / sec) of the first surface of the multilayer film of the pressing and cutting edge satisfies the relational expression (1). Control the speed of movement to

<Other process>
The method for producing a sheet film according to the present embodiment may include steps other than the above-described cutting step. For example, a multilayer film producing step for producing a multilayer film, winding a multilayer film wound in a roll shape The unwinding process to take out, the conveyance process which conveys a multilayer film or sheet film, the drying process which dries a multilayer film or a sheet film, etc. are mentioned.

<Multilayer film>
The multilayer film is not particularly limited as long as it has a pressure-sensitive adhesive layer. The multilayer film is, for example, an optical laminate film. In the case of the optical laminated film, even if it is minute unevenness, it tends to be a problem in appearance. The thickness of the multilayer film is, for example, 5 to 3000 μm, preferably 20 to 500 μm. The layer configuration of the multilayer film is preferably a layer configuration in which the pressure-sensitive adhesive layer is not exposed to the outermost surface so that stains do not easily adhere to the pressure-sensitive adhesive layer in the cutting step.

  When the multilayer film has a pressure-sensitive adhesive layer, when it is cut using a press-cutting blade, streak-like fine irregularities are likely to be generated in the vicinity of the cut surface of the surface of the multilayer film. The occurrence of such minute unevenness can be suppressed. More specifically, the minute unevenness is more likely to be a stripe-like convex extending in a direction substantially parallel to the cut surface, and often occurs on the second surface in contact with the blade receiving plate. Although the mechanism by which the micro unevenness is generated is not clear, as one possible mechanism, the penetration of the cutting edge causes different shear stress in each layer, and the difference in the shear stress acting on the two layers in contact with the pressure sensitive adhesive layer. As a result, the pressure-sensitive adhesive layer may be locally deformed. It is presumed that such local deformation is attributable to the softness of the pressure-sensitive adhesive layer as compared with other layers.

  FIG. 8 is an image view showing streak-like minute unevenness generated near the cut surface of the surface of the multilayer film. The mechanism of the generation of the minute unevenness described with reference to FIG. 8 is one possible mechanism, and the minute unevenness suppressed by the method of manufacturing the sheet film according to the present embodiment is caused by such a mechanism. It is not limited to the unevenness, and is not limited to the minute unevenness schematically shown in FIG. In FIG. 8, a multilayer film including a layer 101, an adhesive layer 102, and a layer 103 is assumed as the multilayer film 10 to be cut. When the cutting edge 211 is made to enter the multilayer film 10, different shear stress is generated in each layer, and the adhesive layer 102 is softer than the layer 101 and the layer 103 adjacent thereto, and therefore the slip acting on the two layers 101 and 103 is generated. Due to the difference in stress, the local area in the vicinity of the cut surface of the pressure-sensitive adhesive layer 102 is slightly raised to form a ridge 102 a. Due to the ridges 102 a of the pressure-sensitive adhesive layer 102, the layer 103 adjacent to the pressure-sensitive adhesive layer 102 may be slightly raised to form ridges 103 a. Thus, the ridges 102a formed on the pressure-sensitive adhesive layer 102 and the ridges 103a formed on the layer 103 cause streak-like irregularities to be visually recognized in appearance.

(Pressure-sensitive adhesive layer)
The pressure-sensitive adhesive layer can be composed of a pressure-sensitive adhesive composition containing a resin such as (meth) acrylic, rubber, urethane, ester, silicone or polyvinyl ether as a main component. Among them, a pressure-sensitive adhesive composition comprising a (meth) acrylic resin excellent in transparency, weather resistance, heat resistance and the like as a base polymer is preferable. The pressure-sensitive adhesive composition may be active energy ray curable or thermosetting.

  Examples of the (meth) acrylic resin (base polymer) used in the pressure-sensitive adhesive composition include butyl (meth) acrylate, ethyl (meth) acrylate, isooctyl (meth) acrylate, and (meth) acrylic acid 2- (2-) The polymer or copolymer which makes 1 type, or 2 or more types of (meth) acrylic acid esters like ethylhexyl a monomer is used suitably. It is preferable to copolymerize a polar monomer to the base polymer. Examples of polar monomers include (meth) acrylic acid, 2-hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, glycidyl Examples thereof include monomers having a carboxyl group, a hydroxyl group, an amido group, an amino group, an epoxy group and the like, such as meta) acrylate.

  The pressure-sensitive adhesive composition may contain only the above-mentioned base polymer, but usually further contains a crosslinking agent. The crosslinking agent is a divalent or higher metal ion which forms a carboxylic acid metal salt with a carboxyl group; a polyamine compound which forms an amide bond with a carboxyl group; poly Examples thereof include epoxy compounds and polyols which form an ester bond with a carboxyl group; and polyisocyanate compounds which form an amide bond with a carboxyl group. Among these, polyisocyanate compounds are preferable.

  An active energy ray-curable pressure-sensitive adhesive composition has the property of being cured by irradiation with active energy rays such as ultraviolet rays and electron beams, and has adhesiveness even before active energy ray irradiation. Etc., and is a pressure-sensitive adhesive composition having a property of being cured by irradiation of active energy rays and capable of adjusting adhesion. The active energy ray-curable pressure-sensitive adhesive composition is preferably ultraviolet-curable. The active energy ray-curable pressure-sensitive adhesive composition further contains an active energy ray-polymerizable compound in addition to the base polymer and the crosslinking agent. Furthermore, if necessary, a photopolymerization initiator, a photosensitizer, etc. may be contained.

  The pressure-sensitive adhesive composition includes fine particles for imparting light scattering properties, beads (resin beads, glass beads, etc.), glass fibers, resins other than the base polymer, tackifiers, fillers (metal powder and other inorganic powders) And the like), additives such as an antioxidant, an ultraviolet light absorber, a dye, a pigment, a coloring agent, an antifoaming agent, a corrosion inhibitor, and a photopolymerization initiator.

  It can form by apply | coating the organic solvent dilution liquid of the said adhesive composition on a base material, and making it dry. When an active energy ray-curable pressure-sensitive adhesive composition is used, the formed pressure-sensitive adhesive layer can be irradiated with active energy rays to obtain a cured product having a desired degree of curing.

  The thickness of the pressure-sensitive adhesive layer can be, for example, 1 to 40 μm. When the thickness of the pressure-sensitive adhesive layer is 1 to 40 μm, streak-like fine unevenness is easily generated by the cut-off process, but according to the method for producing a sheet film of this embodiment, the thickness of the pressure-sensitive adhesive layer is 1 to 40 μm. Even if there is, it is possible to suppress the occurrence of streak-like minute unevenness.

  The pressure-sensitive adhesive layer can exhibit a storage modulus of 0.15 to 1 MPa at a temperature of 20 ° C. and an angular frequency of 1,000 radians / sec. When the pressure-sensitive adhesive layer has such a storage elastic modulus, it is often softer and more likely to have fine unevenness than the other layers, but according to the method for producing a sheet film of the present embodiment, the pressure-sensitive adhesive layer Even if the storage elastic modulus at a temperature of 20 ° C. is 0.15 to 1 MPa, the occurrence of minute irregularities can be suppressed.

  The storage elastic modulus of the pressure-sensitive adhesive layer can be measured using a commercially available visco-elasticity measuring device, for example, a visco-elasticity measuring device “DYNAMIC ANALYZER RDA II” manufactured by REOMETRIC.

  As a method for adjusting the storage elastic modulus to the above range, an oligomer, specifically, a urethane (meth) acrylate-based oligomer is further added to a base polymer or a pressure-sensitive adhesive composition further containing a crosslinking agent. An active energy ray-curable pressure-sensitive adhesive composition (preferably a UV-curable pressure-sensitive adhesive composition) may be mentioned. More preferably, the pressure-sensitive adhesive layer is appropriately cured by irradiation with active energy rays.

(Reference adhesive layer)
The multilayer film used or manufactured by the manufacturing method of the sheet film of this embodiment has an adhesive layer of n layer (n is an integer greater than or equal to 1). When the pressure-sensitive adhesive layer contained in the multilayer film is a single layer, the pressure-sensitive cutting edge speed is controlled so that the above-mentioned relational expression (1) is satisfied, using the pressure-sensitive adhesive layer as a reference pressure-sensitive adhesive layer. When there are a plurality of pressure-sensitive adhesive layers contained in the multilayer film, it is preferable to use a pressure-sensitive adhesive layer which has a finding that it is easy to cause asperities in the cut-off process to be the reference pressure-sensitive adhesive layer. The inventors of the present invention have found that the pressure-sensitive adhesive layers exemplified in the following i) and ii) are likely to cause asperities in the punching process, and are exemplified as the reference pressure-sensitive adhesive layer.

i) an adhesive layer having a minimum storage modulus at a temperature of 20 ° C.,
ii) A pressure-sensitive adhesive layer under the outermost surface layer, in which the multilayer film has a separate film of the outermost surface layer and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film.

  In addition, in the manufacturing method of the sheet film of this embodiment, even if it is a case where it is a case where any of the adhesive layer of n layer is made into a reference | standard adhesive layer, the speed of a press cutting edge satisfy | fills relational expression (1) Is preferred.

(Example of layer structure of multilayer film)
FIG. 9 is a schematic cross-sectional view schematically showing an example of a specific layer configuration of a multilayer film used or manufactured in the method of manufacturing a sheet film according to the present embodiment. The multilayer film 10d includes a polarizing plate 100 including a polarizer (not shown in FIG. 9), a protect film 60 laminated on one surface thereof, and a first pressure-sensitive adhesive layer 31 laminated on the other surface. A peelable separate film 70 for temporarily protecting the first pressure-sensitive adhesive layer 31 is laminated on the outer surface of the first pressure-sensitive adhesive layer 31. On the other hand, the surface of the polarizing plate 100 on the protective film 60 side (the surface to which the protective film 60 is bonded) and the surface on the first pressure-sensitive adhesive layer 31 side (the surface to which the first pressure-sensitive adhesive layer 31 is bonded) are It can be the surface of a protective film, another optical film or a layer applied onto the film.

  The protective film 60 may be laminated by laminating the polarizing plate 100 on one side which is adhesive on one side and non-adhesive on the other side and is adhesive. As such a protective film 60, a so-called self-adhesive protective film may be mentioned. The self-adhesive protection film is, for example, a resin film composed of a non-adhesive resin layer 61 made of a non-adhesive resin and an adhesive resin layer 62 made of a self-adhesive resin. As the self-adhesive protection film, for example, "TRETEC" (Toray Film Co., Ltd.) and the like can be mentioned. Moreover, it is comprised by the resin film (base film) 61 and the 2nd adhesive layer 62 laminated | stacked on it, and the protective film by which lamination lamination is carried out to the polarizing plate 100 via this adhesive layer is also mentioned. . When the protective film 60 has the second pressure-sensitive adhesive layer 62, the storage elastic modulus thereof is usually larger than the storage elastic modulus of the first pressure-sensitive adhesive layer.

  The polarizing plate 100 is a polarizing element including at least a polarizer and a first pressure-sensitive adhesive layer 31, and further includes a protective film usually bonded to one side or both sides of the polarizer. The polarizing plate 100 may include, in addition to the protective film, another optical film such as a film having an optical function different from that of the polarizer, or a layer added on the film such as an optical layer. Various optical films including a protective film can be bonded via an adhesive layer or a pressure-sensitive adhesive layer. The polarizing plate 100 may or may not include the pressure-sensitive adhesive layer. When the pressure-sensitive adhesive layer is included, the pressure-sensitive adhesive layer included in the polarizing plate 100 is one of the n-layer pressure-sensitive adhesive layers included in the multilayer film.

  The thickness of the polarizing plate 100 is usually 20 to 200 μm, preferably 30 to 150 μm, more preferably 40 to 120 μm, and still more preferably 50 to 100 μm.

  The multilayer film 10d is obtained by laminating another raw material film, which is continuously unrolled from the film roll, to the raw material film, which is continuously unrolled and conveyed from the film roll, and the obtained long laminate is obtained. It may be a film produced by a so-called roll-to-roll method of winding a film into a roll, or a multilayer film obtained by further cutting this. In the method for producing a sheet film according to the present embodiment, the multilayer film 10d is cut in the cutting step to produce a sheet film.

  When the multilayer film 10d includes both the first pressure-sensitive adhesive layer 31 and the second pressure-sensitive adhesive layer 62 as the pressure-sensitive adhesive layer, the first pressure-sensitive adhesive layer 31 on which the peelable separate film 70 is laminated is usually , It is easy to produce fine unevenness in the punching process. It is considered that this may be due to the separation film 70 being exfoliated or shifted once due to the action of shear stress and the displacement of the adhesive layer being fixed.

  When the multilayer film 10d is cut by the cutting device shown in FIG. 4, the protect film 60 side is the first surface, the separate film 70 side is the second surface, and the separate film 70 is in contact with the blade support plate 22. The resin film 61 constituting the protect film 60 may be a blade receiving plate, with the separate film 70 side as the first surface and the protect film 60 side as the second surface. 22 may be placed on the mounting table 23 and cut so as to contact the surface 22. According to the method of manufacturing a sheet film of the present embodiment, even when the multilayer film 10d is placed in any direction, it is possible to suppress the occurrence of streak-like minute unevenness due to the punching process.

  Although the shape of the uncut multilayer film 10d is not particularly limited, it is typically long (strip). Although the length in the longitudinal direction and the length in the width direction of the uncut multilayer film 10d are not particularly limited, the length in the longitudinal direction of the multilayer film 10d is usually 100 m to 20,000 m, and the length in the width direction The length is 1,000 mm to 1,500 mm. In addition, after cutting the multilayer film 10d into small pieces of the multilayer film 10d, it may be subjected to a punching process. In this case, the shape of the multilayer film 10d of small pieces is not particularly limited, but it is preferable to have a rectangular shape having long sides and short sides, and is typically rectangular. The length of the long side and the short side is not particularly limited. For example, the length of the long side is 900 mm or less, and the length of the short side is 800 mm or less.

  The size, shape and cutting angle of the sheet film are not particularly limited. The sheet film is preferably in the form of a square, more preferably in the form of a square having a long side and a short side. This rectangular shape is preferably rectangular. When the sheet film is rectangular, the length of the long side is, for example, 50 mm to 300 mm, preferably 70 mm to 200 mm. The length of the short side is, for example, 30 mm to 200 mm, preferably 40 mm to 100 mm. The minute unevenness formed on the surface of the sheet film in the vicinity of the cut surface in the punching process tends to be more noticeable as the size of the sheet film is smaller, but it tends to be a defect on the appearance, but according to the sheet film manufacturing method of this embodiment, Even when the size of the sheet film is small, it is possible to prevent the occurrence of minute unevenness.

(1) Polarizer A polarizer absorbs linearly polarized light having a plane of vibration parallel to its absorption axis, and absorbs linearly polarized light having a plane of vibration perpendicular to the absorption axis (parallel to the transmission axis). It is a type | mold polarizer and can use suitably the polarizing film which carried out adsorption orientation of the dichroic dye to the polyvinyl alcohol-type resin film. The polarizer is, for example, a step of uniaxially stretching a polyvinyl alcohol-based resin film; a step of adsorbing a dichroic dye by dyeing a polyvinyl alcohol-based resin film with a dichroic dye; a polyvinyl dye to which a dichroic dye is adsorbed It can be manufactured by a method including the steps of: treating an alcohol-based resin film with an aqueous boric acid solution; and washing with water after treatment with an aqueous boric acid solution.

  The thickness of the polarizer is preferably 50 μm or less, and more preferably 30 μm or less. Setting the thickness of the polarizer to 30 μm or less is advantageous for reducing the thickness of the polarizing plate 100 and hence the image display device. The thickness of the polarizer is usually 2 μm or more (eg, 5 μm or more).

(2) Protective Film A protective film which can be laminated on one side or both sides of a polarizer is a translucent (preferably optically transparent) thermoplastic resin, for example, a chain-like polyolefin resin (polypropylene resin) Etc.), polyolefin resins such as cyclic polyolefin resins (norbornene resins); cellulose resins such as triacetyl cellulose and diacetyl cellulose; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polycarbonate resins; (Meth) acrylic resin such as methyl methacrylate resin; polystyrene resin; polyvinyl chloride resin; acrylonitrile butadiene styrene resin; acrylonitrile styrene resin; polyvinyl acetate resin polyvinylidene chloride resin Polyamide-based resin; Polyacetal-based resin; Modified polyphenylene ether-based resin; Polysulfone-based resin; Polyether sulfone-based resin; Polyarylate-based resin; Polyamide-imide-based resin; Polyimide-based resin, etc. Among these, polyolefin resins and cellulose resins are preferably used. In addition, in this specification, "(meth) acrylic-type resin" represents at least 1 sort (s) chosen from the group which consists of acrylic resin and methacrylic resin. The same applies to other terms with "(meth)".

  The thickness of the protective film is usually 1 to 100 μm, but is preferably 5 to 60 μm and more preferably 5 to 50 μm from the viewpoint of strength and handleability.

  At least one of the protective films has a hard coat layer, an antiglare layer, a light diffusion layer, and a retardation layer (having a retardation value of 1⁄4 wavelength) on its outer surface (surface opposite to the polarizer). It may be provided with a surface treatment layer (coating layer) such as a phase difference layer, etc., an antireflective layer, an antistatic layer, an antifouling layer, or an optical layer.

  The protective film can be bonded to the polarizer, for example, via an adhesive layer. As the adhesive for forming the adhesive layer, a water-based adhesive, an active energy ray-curable adhesive, or a thermosetting adhesive can be used, preferably a water-based adhesive or an active energy ray-curable adhesive. .

(3) Other Optical Film The polarizing plate 100 can include other optical films other than the polarizer and the protective film, and representative examples thereof are a brightness enhancement film and a retardation film. When the polarizing plate 100 includes another optical film, the protect film 60 may be laminated on the surface of the optical film.

(4) First Pressure-Sensitive Adhesive Layer The first pressure-sensitive adhesive layer 31 is a pressure-sensitive adhesive layer disposed on the outermost surface of the polarizing plate 100, and a multilayer film is attached to an image display element (for example, liquid crystal cell) or another optical member. It can be used to match. The thickness of the first pressure-sensitive adhesive layer 31 can be 1 to 40 μm, but from the viewpoint of thinning of the polarizing plate 100 and from the viewpoint of suppressing dimensional change of the polarizing plate 100 while maintaining good processability It is preferable to set it as 25 micrometers (for example, 3-20 micrometers, further 3-15 micrometers). The description of the above-mentioned pressure-sensitive adhesive layer is applied to the material of the first pressure-sensitive adhesive layer 31 as it is.

(5) Separate Film The separate film 70 is a film temporarily attached to protect the surface of the first pressure-sensitive adhesive layer 31 until the first pressure-sensitive adhesive layer 31 is bonded to an image display element (for example, a liquid crystal cell) or another optical member. The separate film 70 is usually made of a thermoplastic resin film which has been subjected to release treatment on one side, and the release treated surface is bonded to the first pressure-sensitive adhesive layer 31. The thermoplastic resin constituting the separate film 70 may be, for example, a polyethylene-based resin such as polyethylene, a polypropylene-based resin such as polypropylene, or a polyester-based resin such as polyethylene terephthalate or polyethylene naphthalate. Also on the surface of the third pressure-sensitive adhesive layer 32, a separate film similar to the above can be attached in order to temporarily adhere and protect the surface until the optical film such as the brightness enhancement film 50 is attached. The thickness of the separate film 70 is, for example, 10 to 100 μm. When the thickness of the separate film in direct contact with the first pressure-sensitive adhesive layer 31 is 50 μm or less when the storage elastic modulus of the first pressure-sensitive adhesive layer 31 is 0.15 to 1 MPa, (1) The method of the present invention is preferably applied because minute unevenness is generated in the pressure-sensitive adhesive layer 31 in many cases.

(6) Protect Film The protect film 60 is composed of a resin film 61 and a non-adhesive resin layer 62 or a second pressure-sensitive adhesive layer 62 laminated thereon. The protective film 60 is a film for protecting the surface of the polarizing plate 100, and usually, for example, an adhesive resin layer 62 which the polarizing plate with the protective film has after being bonded to an image display element or another optical member. Alternatively, the entire second pressure-sensitive adhesive layer 62 is peeled off and removed.

  The resin constituting the resin film 61 is, for example, a thermoplastic resin such as a polyethylene resin such as polyethylene, a polypropylene resin such as polypropylene, a polyester resin such as polyethylene terephthalate or polyethylene naphthalate, or a polycarbonate resin. be able to. Preferably, polyester resins such as polyethylene terephthalate are used. The resin film 61 may have a single-layer structure or a multi-layer structure, but preferably has a single-layer structure from the viewpoint of easiness of production and cost. The description of the first pressure-sensitive adhesive layer 31 described above is cited for the second pressure-sensitive adhesive layer 62.

[Sheet-fed film manufacturing equipment]
The manufacturing apparatus of the sheet film which concerns on this embodiment cut | disconnects the multilayer film which has an adhesive layer, and has a cutting part which obtains a sheet film from a multilayer film. The cutting portion includes a pushing / cutting blade disposed in the multilayer film so as to be able to enter from the first surface of the multilayer film to the second surface of the multilayer film. The description of the above-mentioned cutting device in the method for producing a sheet film is applied as it is to the cutting portion. For the multilayer film, the description of the above-mentioned multilayer film in the method for producing a sheet film is applied as it is.

  The apparatus for producing a sheet film according to the present embodiment may be provided with components other than the above-mentioned cutting part, for example, a multilayer film producing part producing a multilayer film, and a multilayer film wound in a roll. The unwinding part which unwinds, the conveyance part which conveys a multilayer film or sheet film, the drying part which dries a multilayer film or a sheet film, etc. are mentioned.

[Cutting method of multilayer film]
The method of cutting a multilayer film according to the present embodiment includes a push-cutting process of cutting the multilayer film by advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film. Including. As for the cutting method, the description of the above-mentioned cutting step in the method for producing a sheet film is applied as it is.

  Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited by these examples.

[Multilayer film A]
As the multilayer film A to be cut, a cycloolefin polymer (COP) polarizing plate (SRD 341 mass-produced raw fabric) with a rectangular protect film having a thickness of 185 μm and a long side of 300 mm and a short side of 210 mm was used. The COP polarizing plate with a protective film is, from the top, a protective film (58 μm), a TAC film (25 μm) as a protective film, a PVA film (12 μm) as a polarizer, a COP film (23 μm), a first adhesive layer ( 20 μm), a PET film (38 μm) as a separate film is laminated. The protective film had one side tacky and the other side non-tacky, and one tacky side was stuck in contact with the TAC film.

The first pressure-sensitive adhesive layer had a storage modulus of 0.34 MPa at a temperature of 20 ° C. and an angular frequency of 1,000 rad / s. In the multilayer film A, the first pressure-sensitive adhesive layer is a reference pressure-sensitive adhesive layer. For the standard adhesive layer (first adhesive layer), dynamic visco-elastic property measurement is performed by frequency sweep at a temperature of 20 ° C. using a viscoelasticity measuring apparatus “DYNAMIC ANALYZER RDA II” manufactured by REOM ETRICS, based on the measured values. When the storage modulus is derived a frequency omega ₁ showing the 3.0 × ¹⁰ 5 (Pa), it was 1.20 × ¹⁰ 2 (1 / sec). Similarly, when the storage modulus on the basis of the measured values to derive the frequency omega ₂ showing a 6.0 × ¹⁰ 5 (Pa), it was 6.03 × ¹⁰ 2 (1 / sec).

[Multilayer film B]
The multilayer film B uses a pressure-sensitive adhesive composition different from the pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer of the multilayer film A as the pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer. The structure is the same as that of multilayer film A except that the thickness is 15 μm and the thickness of multilayer film B is 180 μm. The first pressure-sensitive adhesive layer had a storage modulus of 0.65 MPa at a temperature of 20 ° C. and an angular frequency of 1,000 rad / s. For the multilayer film B, the first pressure-sensitive adhesive layer was used as a reference pressure-sensitive adhesive layer. For the standard adhesive layer, dynamic visco-elastic property measurement is performed by frequency sweep at a temperature of 20 ° C. using a viscoelasticity measuring apparatus “DYNAMIC ANALYZER RDA II” manufactured by REOMETRICH, and the storage elastic modulus is 3.0 based on the measured value. It was 1.62x10 (1 / second) when frequency (omega) ₁ which shows * 10 < ⁵ > (Pa) was derived | led-out. Similarly, when a frequency ω ₂ indicating a storage elastic modulus of 6.0 × 10 ⁵ (Pa) was derived based on the measured value, it was 1.38 × 10 ² (1 / second).

Example 1
(Cutting test)
A cutting test was performed using the cutting apparatus shown in FIG. 4 provided with the cutting blade member 21a shown in FIG. As the cutting blade 211a of the cutting blade member 21a, a Thomson blade having a length of 614 mm in the longitudinal direction (manufactured by Ogino Seiki Seisakusho Co., Ltd.) was used.

First, the multilayer film A was mounted on the mounting table 23 so as to be in contact with the blade receiving plate 22. At this time, the PET film (58 μm) constituting the protective film was placed on the upper side, and the PET film (38 μm) as a separate film was placed on the lower side. Then, the cutting blade 211a is made to enter the multilayer film A so that the velocity on the surface of the protect film becomes 7.6 × 10 ⁴ (μm / sec), and cut in a direction orthogonal to the absorption axis to protect The COP polarizing plate with film was divided into two equal parts.

(Evaluation of streak-like unevenness generation)
A cutting test was performed on five samples, and the presence or absence of the occurrence of streaks in the vicinity of the cut surface of the surface of the cut piece obtained by dividing the five samples into two was visually evaluated. The evaluation results are shown in Table 1.

Example 2
In the cutting test, cutting is performed in the same manner as in Example 1 except that the cutting blade 211a is advanced to the multilayer film A so that the velocity on the surface of the protect film is 1.2 × 10 ⁵ μm / sec. A test was conducted to evaluate the presence or absence of the occurrence of streaks of irregularities. The evaluation results are shown in Table 1.

[Example 3]
In the cutting test, the point that the multilayer film B was used instead of the multilayer film A, and the cutting blade 211a to the multilayer film B so that the velocity on the surface of the protect film is 2.1 × 10 ⁴ μm / sec. A cutting test was carried out in the same manner as in Example 1 except for the point of penetration, to evaluate the presence or absence of the occurrence of streak-like irregularities. The evaluation results are shown in Table 1.

Example 4
In the cutting test, cutting is performed in the same manner as in Example 3 except that the cutting blade 211a is advanced to the multilayer film B so that the velocity on the surface of the protect film is 7.6 × 10 ⁴ μm / sec. A test was conducted to evaluate the presence or absence of the occurrence of streaks of irregularities. The evaluation results are shown in Table 1.

Comparative Example 1
In the cutting test, cutting is performed in the same manner as in Example 1 except that the cutting blade 211a is advanced to the multilayer film A so that the velocity on the surface of the protect film is 6.6 × 10 ³ μm / sec. A test was conducted to evaluate the presence or absence of the occurrence of streaks of irregularities. The evaluation results are shown in Table 1.

Comparative Example 2
In the cutting test, cutting is performed in the same manner as in Example 1 except that the cutting blade 211a is advanced to the multilayer film A so that the velocity on the surface of the protect film is 2.1 × 10 ⁴ μm / sec. A test was conducted to evaluate the presence or absence of the occurrence of streaks of irregularities. The evaluation results are shown in Table 1.

  10, 10a, 10b, 10c, 10d multilayer film, 11 sheet film, 20 cutting device, 21, 21a, 21b pushing / cutting blade members, 22 blade receiving plate, 23 mounting table, 31 first pressure-sensitive adhesive layer, 60 protect film, 61 resin film, 62 second pressure-sensitive adhesive layer, 70 separate film, 100 polarizing plate, 101 first surface, 102 second surface, 211a, 211b pushing / cutting blade, 212a, 212b elastic body, 213a holding portion.

Claims (12)

A method for producing a sheet film, comprising a cutting step of obtaining a sheet film from the multilayer film by cutting a multilayer film having a pressure-sensitive adhesive layer of n layers (n is an integer of 1 or more),
The cutting step includes a push-off step of cutting the multilayer film by advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, the cutting step.
When the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film is any one of the n pressure-sensitive adhesive layers, the pressure-sensitive adhesive layer is used as the reference pressure-sensitive adhesive layer The manufacturing method of the sheet film which satisfy | fills the following relational expression (1).
t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]   Among the pressure-sensitive adhesive layers, a pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C. and an angular frequency of 1,000 radians / sec is used as the reference pressure-sensitive adhesive layer. Method. The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The method for producing a sheet film according to claim 1, wherein the pressure-sensitive adhesive layer under the outermost surface layer is used as the reference pressure-sensitive adhesive layer.   The method for producing a sheet film according to any one of claims 1 to 3, wherein the multilayer film has a polarizer. An apparatus for producing a sheet film, comprising a cutting portion for cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more) to obtain a sheet film from the multilayer film,
The cutting unit is a pressing / cutting blade disposed so as to be able to enter the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, and a control unit that controls the movement of the pressing / cutting blade And
The control unit is configured to set the velocity V (μm on the first surface of the multilayer film) of the pressing / cutting blade when one of the n pressure-sensitive adhesive layers is the reference pressure-sensitive adhesive layer. An apparatus for manufacturing a sheet-fed film, which controls (a) / sec) to satisfy the following relational expression (1).
t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]   Among the pressure-sensitive adhesive layers, a pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C. and an angular frequency of 1,000 radians / sec is used as the reference pressure-sensitive adhesive layer. apparatus. The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The manufacturing apparatus of the sheet film of Claim 5 which makes the adhesive layer under the said outermost surface layer the said reference | standard adhesive layer.   The apparatus for producing a sheet film according to any one of claims 5 to 7, wherein the multilayer film has a polarizer. A cutting method for cutting a multilayer film having an adhesive layer of n layers (n is an integer of 1 or more),
Including a pushing and cutting step of advancing the inside of the multilayer film from the first surface of the multilayer film toward the second surface of the multilayer film, and cutting the multilayer film;
When the velocity V (μm / sec) of the press-cutting blade on the first surface of the multilayer film is one of n pressure-sensitive adhesive layers, one of the pressure-sensitive adhesive layers is used as a reference pressure-sensitive adhesive layer The cutting method of the multilayer film which satisfy | fills the following relationship (1).
t / V <1 / ω ₁ (1)
[In the above-mentioned relational expression (1), t represents the thickness (μm) of the multilayer film, ω ₁ is the storage calculated based on the measurement value of the dynamic viscoelasticity measurement by the frequency sweep at the temperature of 20 ° C. of the reference adhesive layer The elastic modulus represents a frequency (1 / second) indicating 3.0 × 10 ⁵ (Pa). ]   The method for cutting a multilayer film according to claim 9, wherein among the pressure-sensitive adhesive layers, a pressure-sensitive adhesive layer having a minimum storage elastic modulus at a temperature of 20 ° C and an angular frequency of 1,000 rad / s is used as the reference pressure-sensitive adhesive layer. . The multilayer film has a separate film of the outermost surface layer, and a pressure-sensitive adhesive layer under the outermost surface layer exposed to the outermost surface by peeling of the separate film,
The method for cutting a multilayer film according to claim 9, wherein the pressure-sensitive adhesive layer under the outermost surface layer is the reference pressure-sensitive adhesive layer.   The method for cutting a multilayer film according to any one of claims 9 to 11, wherein the multilayer film has a polarizer.

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