JP6224284B1 - Adhesive film - Google Patents

Abstract

It is an object of the present invention to provide a pressure-sensitive adhesive film that is excellent in releasability of a release film and that is less likely to wrinkle or loosen after being peeled off and that is excellent in sticking. An adhesive tape including a release film, a resin film, and an adhesive layer having a first adhesive surface bonded to the resin film and a second adhesive surface bonded to the release film. 4, the product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film 30 is 0.3 MPa · m or less, and the total thickness of the resin film 11 and the pressure-sensitive adhesive layer 20 is 10 μm or less. The peeling film 30 has a peeling force of 40 mN / 25 mm or less at a peeling speed of 300 mm / min with respect to the second adhesive surface. [Selection] Figure 1

Description

  The present invention relates to an adhesive film.

  In small electronic products such as mobile phones and notebook personal computers, a heat dissipation sheet such as a heat-dissipating graphite sheet is used in order to promote heat dissipation of electronic components provided inside. In particular, in a graphite sheet, the surface of the sheet is protected with a pressure-sensitive adhesive tape with a colored layer in order to prevent chipping, peeling, and the like (see, for example, Patent Document 1). About the adhesive tape with a colored layer, in order to improve the heat dissipation of the electronic component by size reduction of an electronic product or a graphite sheet, it is desirable to make the thickness thinner. For example, the thickness of the pressure-sensitive adhesive tape with a colored layer is as very thin as 10 μm or less.

  In Patent Document 1, as an adhesive tape used for protecting a graphite sheet, a resin film layer having a thickness of 1 μm to 6 μm, an adhesive layer having a thickness of 1 μm to 6 μm, and a thickness of 0.5 μm to 2 μm. A colored substrate having an adhesive layer on at least one surface of a colored substrate having the following colored layer, wherein the colored substrate has a light transmittance of 0.1% to 10% and a thickness of 3 μm to 10 μm. An adhesive tape is disclosed.

  Such a colored pressure-sensitive adhesive tape comprises, for example, a pressure-sensitive adhesive layer, a resin film provided on the pressure-sensitive adhesive layer, and a colored layer provided on the resin film, and maintaining the smoothness of the pressure-sensitive adhesive layer or In order to prevent contamination of the pressure-sensitive adhesive layer, a release film is attached to the pressure-sensitive adhesive layer side. Furthermore, in the process of manufacturing a colored adhesive tape, the adhesive tape is handled (stored, transported, etc.) by winding the adhesive tape into a roll.

JP 2013-203965 A

  However, the thinner the adhesive tape is, the lower the rigidity of the adhesive tape is. Specifically, in an ultra-thin adhesive tape with a total thickness of the resin film and the adhesive layer of 10 μm or less, wrinkles or slack occurs when the release film is peeled off from the adhesive film and applied to an adherend. Or the release film is difficult to peel off from the pressure-sensitive adhesive layer, and the suitability to adhere to the adherend may be a problem. Furthermore, depending on the peeling force between the release film and the pressure-sensitive adhesive layer, when the release film is peeled off from the pressure-sensitive adhesive layer, the release film is difficult to peel off from the pressure-sensitive adhesive layer, or when producing a pressure-sensitive adhesive tape in a roll-to-roll system, When the pressure-sensitive adhesive tape is wound or the pressure-sensitive adhesive tape after being wound is handled, wrinkles or slack may occur in the pressure-sensitive adhesive tape, and the processability may be inferior.

  In view of the circumstances as described above, an object of the present invention is to provide an adhesive film that is excellent in peelability of a release film and that does not easily wrinkle or sag after the release film is peeled off and that is excellent in sticking suitability. Furthermore, when manufacturing an ultra-thin adhesive film using the roll-to-roll method, when the adhesive film is wound up or when the adhesive film is handled after being wound up, the adhesive film is less prone to wrinkling or loosening. The object is to provide an adhesive film excellent in suitability.

  As a result of intensive studies by the present inventors, when the total thickness of the resin film and the pressure-sensitive adhesive layer is extremely thin, 10 μm or less, the peeling force between the pressure-sensitive adhesive layer and the peeling film and the Young's modulus at 25 ° C. of the peeling film ( When the product of (MPa) and thickness (m) is in a specific range, the release film can be easily peeled off from the adhesive layer, and even when the release film is peeled off from the adhesive film and applied to an adherend. The film does not easily wrinkle or sag, has excellent adhesiveness, and when producing an ultra-thin adhesive film using the roll-to-roll method, the adhesive film is wound up or the adhesive film after being wound up is handled. In doing so, it was found that wrinkles or sags are less likely to occur in the adhesive film, and that it is excellent in processability. Thereby, the said subject was solved. Means for solving the above problems are as follows.

In order to achieve the above object, an adhesive film according to an embodiment of the present invention includes a release film, and an adhesive tape including a resin film and an adhesive layer. The pressure-sensitive adhesive layer has a first pressure-sensitive adhesive surface that is bonded to the resin film and a second pressure-sensitive adhesive surface that is bonded to the release film.
The product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film is 0.3 MPa · m or less.
The total thickness of the resin film and the pressure-sensitive adhesive layer is 10 μm or less.
The peeling force of the peeling film with respect to the second adhesive surface is 40 mN / 25 mm or less at a peeling speed of 300 mm / min.

  According to such an adhesive film, the bending rigidity and peeling force of the release film are optimized, and when the adhesive film is wound up or when the adhesive film after being wound is handled, the adhesive film has wrinkles or slack. Less likely to occur. Furthermore, when peeling a peeling film from an adhesive layer, a peeling film can be efficiently peeled from an adhesive layer.

The release film may have a Young's modulus of 500 MPa or more at 25 ° C.
The resin film may have a Young's modulus of 500 MPa or more at 25 ° C.
The average height (Rc) of the roughness curve element on the surface of the release film opposite to the pressure-sensitive adhesive layer is 500 nm or less.
The thickness of the resin film may be 1 μm or more and 6 μm or less.
The thickness of the pressure-sensitive adhesive layer may be 1 μm or more and 5 μm or less.
Thereby, the rigidity of the release film and the resin film is optimized, and when the adhesive film is wound or when the adhesive film after being wound is handled, wrinkles or slack are less likely to occur.
In the adhesive film, the adhesive strength of the adhesive tape to the stainless steel plate (peeling angle 180 °, peeling speed 300 mm / min) may be 1 N / 25 mm or more and 10 N / 25 mm or less.
As a result, even with an extremely thin structure of 10 μm, when the pressure-sensitive adhesive film is wound up or when the pressure-sensitive adhesive film after being wound is handled, floating may occur between the release film and the pressure-sensitive adhesive layer. Or, it becomes difficult for slack to occur. Moreover, it can adhere | attach suitably to adherends, such as a graphite sheet, Furthermore, it peels from the adherend once stuck, and it becomes easy to reattach.

The pressure-sensitive adhesive layer and the resin film may be attached to the surface of the graphite sheet.
Thereby, since the total thickness of the resin film and the pressure-sensitive adhesive layer is as extremely thin as 10 μm or less, it is possible to prevent and protect the graphite sheet from being chipped, peeled off or the like without impairing heat dissipation.

  As described above, according to the present invention, an adhesive film excellent in sticking suitability and processability is provided.

FIG. 1A is a schematic three-dimensional view of a state in which the pressure-sensitive adhesive film according to this embodiment is wound. FIG. (B) is a schematic sectional drawing of the adhesive film which concerns on this embodiment. FIG. (C) is a schematic cross-sectional view of a state in which the graphite sheet to which the adhesive tape according to the present embodiment has been attached is attached to the housing via a double-sided tape. FIG. 1A is a schematic cross-sectional view of a colored adhesive film according to this embodiment. FIG. (B) is a schematic cross-sectional view of a state in which the graphite sheet to which the colored adhesive tape according to the present embodiment is attached is attached to the housing via a double-sided tape. It is the schematic explaining the manufacturing process of the colored adhesive film which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, XYZ axis coordinates may be introduced.

  [Configuration of adhesive film]

  FIG. 1A is a schematic three-dimensional view of a state in which the pressure-sensitive adhesive film according to this embodiment is wound. FIG.1 (b) is a schematic sectional drawing of the adhesive film which concerns on this embodiment. FIG.1 (c) is a schematic sectional drawing of the state which the graphite sheet with which the adhesive tape which concerns on this embodiment was affixed on the housing | casing via the double-sided tape.

  As shown to Fig.1 (a), the adhesive film 2 which concerns on this embodiment is wound by the winding roll (winding core) 210 in elongate direction DL, for example. The length (full length) in the longitudinal direction DL of the adhesive film 2 wound around the take-up roll 210 is, for example, 6000 m or more and 10000 m or less. The length of the adhesive film 2 in the width direction DW (short direction) orthogonal to the long direction DL is, for example, not less than 800 mm and not more than 1500 mm.

The cross-sectional structure of the adhesive film 2 will be described below.
As shown in FIG. 1B, the adhesive film 2 includes a resin film 11, an adhesive layer 20, and a release film 30. In the example of FIG. 1B, the adhesive film 2 is laminated in the order of release film 30 / adhesive layer 20 / resin film 11. In this embodiment, the release film 30 side may be the lower side and the resin film 11 side may be the upper side. In the adhesive film 2, the release film 30 can be peeled off from the interface between the release film 30 and the adhesive layer 20. Further, when the adhesive film 2 is wound around the take-up roll 210, the upper surface 11 u that is the outermost surface of the adhesive film 2 comes into contact with the lower surface 30 d of the release film 30.

  The release film 30 is provided on the surface of the pressure-sensitive adhesive layer 20 on the side opposite to the resin film 11. In the example of FIG. 1B, the release film 30 is the lowest layer in the adhesive film 2.

The thickness of the release film 30 is not particularly limited, but is preferably 1 × from the viewpoint that the product of the Young's modulus (MPa) and the thickness (m) at 25 ° C. of the release film 30 can be easily adjusted to a range described later. 10 ⁻⁵ m or more and 1 × 10 ⁻⁴ m or less, more preferably 1.5 × 10 ⁻⁵ m or more and 8 × 10 ⁻⁵ m or less, and further preferably 1.7 × 10 ⁻⁵ m. It is 5 × 10 ⁻⁵ m or less, and particularly preferably 2 × 10 ⁻⁵ m or more and 3 × 10 ⁻⁵ m or less. Here, the thickness in the present embodiment is an average value of thicknesses measured from a plurality of points. When the release film 30 has a film base material and a release agent layer provided on the film base material, the above-mentioned “thickness of the release film 30” means the thickness of the film base material. I mean. When the release film 30 has a thickness of less than 1 × 10 ⁻⁵ m, the handling property of the adhesive film is reduced, or a solution containing an adhesive composition is applied onto the release film 30 and heat treatment is performed. In addition, thermal shrinkage of the release film 30 may increase, wrinkles and streaks may occur in the adhesive film 2, and processing suitability may decrease. On the other hand, when the thickness of the release film 30 exceeds 1 × 10 ⁻⁴ m, when the release film 30 is peeled off, a laminate of the resin film 11 and the adhesive layer 20 (hereinafter, this state is referred to as “adhesive tape 4”). ) Is deformed, and it becomes difficult to peel the release film 30 from the pressure-sensitive adhesive layer 20.

  Further, the Young's modulus at 25 ° C. of the release film 30 is not particularly limited, but from the viewpoint that the product of the Young's modulus (MPa) and the thickness (m) at 25 ° C. of the release film 30 can be easily adjusted to the range described later. Preferably, it is 500 MPa or more and 10,000 MPa or less, More preferably, it is 2000 MPa or more and 6000 MPa or less, More preferably, it is 3500 MPa or more and 5000 MPa or less.

  Further, the product of the Young's modulus (MPa) and the thickness (m) at 25 ° C. of the release film 30 is 0.3 MPa · m or less, preferably 0.25 MPa · m or less, more preferably 0.00. 2 MPa · m or less, and more preferably 0.15 MPa · m or less. The lower limit of the product value is not particularly limited, but is preferably 0.01 MPa · m or more, more preferably 0.05 MPa · m or more, and further preferably 0.1 MPa · m or more.

  Further, the 180 ° peeling force with respect to the pressure-sensitive adhesive surface 20b of the pressure-sensitive adhesive layer 20 of the release film 30 is 40 mN / 25 mm or less, preferably 35 mN / 25 mm or less, more preferably, at a peeling speed of 300 mm / min. 30 mN / 25 mm or less. Although a minimum is not specifically limited, Preferably it is 5 mN / 25mm or more, More preferably, it is 10 mN / 25mm or more, More preferably, it is 15 mN / 25mm or more. When the peeling force of the release film 30 is smaller than 5 mN / 25 mm, the adhesive film is peeled off when the adhesive film is wound up or the wound adhesive film is handled when the adhesive film is produced by the roll-to-roll method. In some cases, floating occurs at the interface between the film 30 and the pressure-sensitive adhesive layer 20, and the release film 30 may be peeled off during handling such as storage and transportation of the pressure-sensitive adhesive film. In order for the 180 ° peeling force to be 40 mN / 25 mm or less, it is necessary to appropriately select the pressure-sensitive adhesive layer 20 and the peeling film 30.

  According to the pressure-sensitive adhesive film 2 having such a release film 30, even if the resin film 11 and the pressure-sensitive adhesive layer 20 have a very thin configuration of 10 μm or less, the pressure-sensitive adhesive film 2 is wound up or wound up. When the adhesive film 2 is handled, wrinkles or slack is less likely to occur in the adhesive film 2. Furthermore, when peeling the release film 30 from the pressure-sensitive adhesive layer 20, the release film 30 can be efficiently peeled from the pressure-sensitive adhesive layer 20.

  For example, when the product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film 30 is smaller than 0.01 MPa · m, a solution containing an adhesive composition is applied onto the release film 30 and heat treatment is performed. , The release film 30 is likely to heat shrink, wrinkles and streaks occur in the pressure-sensitive adhesive film 2, the processability is lowered, and the release film 30 itself is too weak to be easily peeled off. Become. When the product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film 30 exceeds 0.3 MPa · m, the release film 30 itself has a high rigidity, and the adhesive film 2 is peeled off when the release film 30 is released. Deformation is likely to cause wrinkles or slack in the adhesive film 2, which is not preferable. Furthermore, after the release film 20 is peeled off, the adhesive tape 4 is liable to be wrinkled or loosened, which is not preferable.

  Even if the product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film 30 is 0.3 MPa · m or less, if the release force of the release film 30 is greater than 40 mN / 25 mm, the release film 30 The adhesion between the film 30 and the pressure-sensitive adhesive layer 20 is too strong, and the release film 30 is difficult to peel off from the interface with the pressure-sensitive adhesive layer 20, and a part of the pressure-sensitive adhesive layer 20 may be peeled off from the resin film 11 together with the release film 30. Even if the peeling film 30 is peeled off, wrinkles or slack is likely to occur in the adhesive film 2 after the peeling film 30 is peeled off.

  The arithmetic average roughness Ra of the lower surface 30d of the release film 30 is preferably 50 nm or less, and more preferably 40 nm or less. The lower limit of Ra of the lower surface 30d is, for example, 10 nm. The average height Rc of the roughness curve element on the lower surface 30d is preferably 500 nm or less, and more preferably 450 nm or less. The lower limit of Rc of the lower surface 30d is, for example, 100 nm. The 10-point average roughness Rzjis of the lower surface 30d is preferably 800 nm or less, and more preferably 700 nm or less. The lower limit of Rzjis of the lower surface 30d is, for example, 100 nm.

  By setting the average height Rc of the roughness curve element of the lower surface 30d of the release film 30 in the above range, when the adhesive film 2 is wound around the take-up roll 210, the upper surface 11u that is the outermost surface of the adhesive film 2 is Even if it contacts the lower surface 30d of the release film 30, the pressure-sensitive adhesive film 2 is less likely to cause blocking and air biting, and is excellent in winding property when the thin pressure-sensitive adhesive film 2 is processed by the roll-to-roll method.

  For example, the dynamic friction coefficient of the upper surface 11u that is the outermost surface of the adhesive film 2 with respect to the lower surface 30d of the release film 30 is not particularly limited, but is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less. is there. Although the minimum of a dynamic friction coefficient is not specifically limited, Preferably it is 0.2 or more, More preferably, it is 0.5 or more, More preferably, it is 1 or more. If the dynamic friction coefficient is within the above range, the pressure-sensitive adhesive film 2 is less likely to cause blocking and air biting, and the winding property when the thin pressure-sensitive adhesive film 2 is processed by the roll-to-roll method is excellent.

  The pressure-sensitive adhesive layer 20 is provided on the surface opposite to the lower surface 30 d of the release film 30. The pressure-sensitive adhesive layer 20 is provided between the release film 30 and the resin film 11. The pressure-sensitive adhesive layer 20 has an adhesive surface 20 a (first adhesive surface) bonded to the resin film 11 and a second adhesive surface 20 b (second adhesive surface) bonded to the release film 30.

  Although the thickness of the adhesive layer 20 is not specifically limited, Preferably it is 1 micrometer or more and 5 micrometers or less, More preferably, they are 1 micrometer or more and 3 micrometers or less. When the thickness of the pressure-sensitive adhesive layer 20 is less than 1 μm, the adhesion between the pressure-sensitive adhesive layer 20 and the graphite sheet is low, and it may be difficult to sufficiently protect the graphite sheet. When the thickness of the pressure-sensitive adhesive layer 20 exceeds 5 μm, the pressure-sensitive adhesive film 2 becomes thick and does not satisfy the demand for thinning.

  The resin film 11 is provided on the surface of the pressure-sensitive adhesive layer 20 on the side opposite to the release film 30. The resin film 11 is a base material for the adhesive film 2.

  The Young's modulus at 25 ° C. of the resin film 11 is not particularly limited, but is preferably 500 MPa or more and 10,000 MPa or less, more preferably 2000 MPa or more and 6000 MPa or less, and further preferably 3500 MPa or more and 5000 MPa or less. By setting the Young's modulus at 25 ° C. of the resin film 11 within the above range, the workability is excellent even if the thickness is small.

  The thickness of the resin film 11 is not particularly limited, but is 1 μm or more and 6 μm or less, preferably 1 μm or more and 3 μm or less. When the thickness of the resin film 11 is less than 1 μm, the strength of the resin film 11 becomes low, and it becomes difficult to convey the film by a roll-to-roll method. When the thickness of the resin film 11 exceeds 6 μm, the pressure-sensitive adhesive film 2 becomes thick and does not satisfy the demand for thinning.

  Moreover, the total thickness of the resin film 11 and the adhesive layer 20 is 10 micrometers or less. It is preferably 2 μm or more and 10 μm or less, more preferably 2.5 μm or more and 9 μm or less, further preferably 3 μm or more and 8 μm or less, and particularly preferably 3.5 μm or more and 6 μm or less. When the total thickness of the resin film 11 and the pressure-sensitive adhesive layer 20 is smaller than 2 μm, the strength of the resin film 11 and the pressure-sensitive adhesive layer 20 is lowered, and it becomes difficult to transport the film by the roll-to-roll method. When the thickness of the resin film 11 and the pressure-sensitive adhesive layer 20 exceeds 10 μm, the pressure-sensitive adhesive film 2 becomes thick and does not satisfy the demand for thinning. If the total thickness of the resin film 11 and the pressure-sensitive adhesive layer 20 is 10 μm or less, the pressure-sensitive adhesive tape 4 can be arranged in the electronic product without harming the internal space of the small electronic product because it is extremely thin.

  The lower limit of the adhesive strength of the adhesive tape 4 to the stainless steel plate (peeling angle 180 °, peeling rate 300 mm / min) is preferably 1 N / 25 mm or more, more preferably 1.2 N / 25 mm or more, and still more preferably. 1.3 N / 25 mm or more. On the other hand, the upper limit of the adhesive strength (peeling angle 180 °, peeling speed 300 mm / min) is not particularly limited, but is preferably 10 N / 25 mm or less, more preferably 7 N / 25 mm or less, and even more preferably 5 N / 25 mm. Or less, and particularly preferably 2.5 N / 25 mm or less.

  By setting the lower limit of the adhesive strength within the above range, even when the adhesive film 2 is wound up, or when the adhesive film 2 after being wound up is handled, even when the adhesive film 2 is extremely thin, the release film 30 and the adhesive are adhered. Floating occurs between the agent layers 20, and wrinkles or slack is less likely to occur. Moreover, if the adhesive strength is in the above range, even a very thin structure of 10 μm can be suitably bonded to the graphite sheet. Furthermore, if the adhesive strength is within the above range, it is easy to peel off the adherend once pasted and to reattach it.

  As shown in FIG.1 (c), the laminated body (adhesive tape 4) of the resin film 11 and the adhesive layer 20 from which the peeling film 30 was peeled can be affixed on the graphite sheet 100, for example. For example, the exposed surface of the pressure-sensitive adhesive layer 20 is bonded to the surface of the graphite sheet 100. Moreover, the graphite sheet 100 is affixed on the housing | casing 102 (for example, electronic component) via the double-sided tape 101. FIG. Thereby, in the graphite sheet 100, heat is diffused also in the Z-axis direction, the X-axis direction, and the Y-axis direction. Thereby, the heat generated from the electronic component is efficiently radiated. Specifically, the adhesive tape 4 is preferably affixed to a graphite sheet installed inside the electronic component.

  Moreover, since the laminated body (adhesive tape 4) of the resin film 11 and the adhesive layer 20 is very thin, the adhesive tape 4 can be arrange | positioned in an electronic product, without harming the internal space of a small electronic product, and heat dissipation. Without impairing the properties, the graphite sheet 100 can be prevented from being chipped, peeled off, and the like can be protected.

  As described above, even when the total thickness of the resin film 11 and the pressure-sensitive adhesive layer 20 is extremely thin, that is, 10 μm or less, the peeling force between the pressure-sensitive adhesive layer 20 and the release film 30 and the release film 30 at 25 ° C. By making the product of the Young's modulus and the thickness within a specific range, the release film 30 is easily peeled from the pressure-sensitive adhesive layer 20. Moreover, when sticking the adhesive film 30 to the graphite sheet 100, wrinkles or slack is hardly generated in the adhesive film 2, and the sticking aptitude is excellent. Further, when the ultra-thin adhesive film 2 is manufactured by the roll-to-roll method, the adhesive film 2 is wrinkled or loosened when the adhesive film 2 is wound up or when the adhesive film 2 is wound up. It is difficult to generate and has excellent processability.

  In the adhesive film 2, you may have layers other than the resin film 11, the adhesive layer 20, and the peeling film 30 according to the use aspect and the characteristic made into the objective. Examples of such a layer include a colored layer, a roughened layer, a hard coat layer, an easy-adhesion layer, a reflective layer, an antiglare layer, a conductive film, and an insulating layer, and a printing layer, a printing layer, and a paint. Examples include a decorative layer such as a coating film. As an example, an adhesive film having a structure in which the colored layer 12 and the roughened layer 15 are formed on the resin film 11 (hereinafter sometimes referred to as a colored adhesive film) will be described below.

  [Configuration of colored adhesive film]

  Fig.2 (a) is a schematic sectional drawing of the colored adhesive film which concerns on this embodiment. FIG. 2B is a schematic cross-sectional view of a state in which the graphite sheet to which the colored adhesive tape according to the present embodiment is attached is attached to the housing via a double-sided tape.

  As shown in FIG. 2A, the colored adhesive film 3 includes a resin film 11, an adhesive layer 20, a release film 30, a colored layer 12, and a roughened layer 15. In the example of FIG. 2A, the colored adhesive film 3 is laminated in the order of release film 30 / adhesive layer 20 / resin film 11 / colored layer 12 / roughened layer 15.

  The colored layer 12 is provided on the surface of the resin film 11 opposite to the pressure-sensitive adhesive layer 20. For example, the colored layer 12 is provided between the resin film 11 and the roughened layer 15. The colored layer 12 is provided in order to impart designability to the colored adhesive film 3. The colored layer 12 is also a layer that improves the adhesion between the resin film 11 and the roughened layer 15. The roughening layer 15 is provided on the surface of the colored layer 12 on the side opposite to the resin film 11.

  The roughening layer 15 is the uppermost layer in the example of FIG. When the colored adhesive film 3 is wound on a take-up roll, the upper surface 15 u that is the outermost surface of the colored adhesive film 3 comes into contact with the lower surface 30 d of the release film 30.

  The arithmetic average roughness Ra of the roughened layer 15 is not particularly limited, but is preferably 0.1 μm or more, more preferably 0.1 or more and 1.0 μm or less, and further preferably 0.2 μm or more. 0.5 μm or less. The average height Rc of the roughness curve element of the roughened layer 15 is 0.5 μm or more, preferably 0.5 μm or more and 5.0 μm or less, more preferably 0.8 or more and 3.0 μm or less. More preferably, it is 1.0 or more and 2.0 μm or less. The 10-point average roughness Rzjis of the roughened layer 15 is not particularly limited, but is preferably 1.0 μm or more, more preferably 1.0 μm or more and 9.0 μm or less, and further preferably 2.0 or more. It is 7.0 μm or less, and particularly preferably 2.5 to 5.0 μm.

  When the roughened layer 15 has a structural surface in the above range, the 60 ° specular gloss of the roughened layer 15 described later can be set within a predetermined range. Thereby, the designability when the graphite sheet with the colored adhesive film 3 is placed inside the electronic component is excellent.

  For example, the dynamic friction coefficient of the upper surface 15u with respect to the lower surface 30d of the release film 30 is not particularly limited, but is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less. Although the minimum of a dynamic friction coefficient is not specifically limited, Preferably it is 0.5 or more, More preferably, it is 1 or more, More preferably, it is 2 or more. When the dynamic friction coefficient is in the above range, when the colored adhesive film 3 is wound around a take-up roll, it is difficult to cause blocking and air biting, and the thin adhesive film 2 is processed by the roll-to-roll method. Excellent winding ability.

  Further, the 60 ° specular gloss of the roughened layer 15 having such roughness is not particularly limited, but is 0.5% or more and 50% or less, preferably 1% or more and 9% or less, more preferably Is 1% or more and 5% or less. Thereby, the laminated body from which the peeling film 30 peeled from the colored adhesive film 3, that is, the laminated body laminated in the order of the pressure-sensitive adhesive layer 20 / the resin film 11 / the colored layer 12 / the roughened layer 15 (hereinafter referred to as this state). In the graphite sheet with “colored adhesive tape 1” affixed, the appearance is matte, and when the colored adhesive tape is installed inside the electronic component, the colored adhesive tape 1 is integrated with the electronic component. Therefore, the design is excellent.

  In the colored adhesive film 3, the layers adjacent to each other in the Z-axis direction may be in direct contact with each other or may be in indirect contact with each other. In the case of indirect contact, an intermediate layer (not shown) that improves adhesion and the like may be interposed between layers adjacent in the Z-axis direction. Moreover, each layer in the colored adhesive film 3 may be a single layer or may be composed of a plurality of layers.

  The thickness of the colored layer 12 is not particularly limited, but is 0.5 μm or more and 10 μm or less, and preferably 0.8 μm or more and 3 μm or less. If the thickness of the colored layer 12 is less than 0.5 μm, the adhesion between the resin film 11 and the roughened layer 15 is lowered, and the roughened layer 15 may be peeled off from the resin film 11 in some cases. On the other hand, when the thickness of the colored layer 12 exceeds 10 μm, the colored adhesive film 3 becomes thick and does not satisfy the demand for thinning.

  The thickness of the roughened layer 15 is not particularly limited, but is 0.5 or more and 10 μm or less, preferably 0.6 μm or more and 3 μm or less, and more preferably 0.8 μm or more and 2 μm or less. When the thickness of the roughened layer 15 is less than 0.5 μm, a desired structural surface cannot be obtained, and when the thickness of the roughened layer 15 exceeds 10 μm, the colored adhesive film 3 becomes thick and there is a demand for thinning. Do not meet.

  By setting the thickness of each layer in the above range, the thickness of the colored adhesive tape 1 after the release film 30 is peeled is about 10 μm, and the colored adhesive tape 1 is configured to be extremely thin.

  Furthermore, as shown in FIG. 2 (b), the colored adhesive tape 1 from which the release film 30 has been peeled is provided with a colored layer 12 in addition to the above-described heat dissipation effect, so that the appearance of the graphite sheet is uneven. Disappears. Furthermore, since the colored adhesive tape 1 is provided with the roughened layer 15, it has a matte appearance. Thereby, since the colored adhesive tape 1 seems to be integrated with the electronic component (it appears to be melted), the colored adhesive tape 1 is hardly noticeable and the design is improved.

  In the pressure-sensitive adhesive film 2 or the colored pressure-sensitive adhesive film 3, at least one of the pressure-sensitive adhesive layer 20, the resin film 11, and the roughened layer 15 may contain a colorant. The colorant is not particularly limited, and examples thereof include carbon black, titanium oxide, calcium carbonate, barium sulfate, yellow iron oxide, red pepper, cyanine blue, aluminum powder, and mica titanium powder. Thereby, the spot on the external appearance of the graphite sheet 100 becomes inconspicuous, and the external appearance of the graphite sheet 100 is further improved. That is, the design properties when the graphite sheet 100 to which the adhesive tape or the colored adhesive tape is affixed are installed inside the electronic component are further improved.

  The material of each layer in the adhesive film 2 is as follows.

[Resin film]
The type of resin used for the resin film is not particularly limited. For example, polyester film made of polyester such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyurethane film, polyethylene film, polypropylene film Cellulose film such as triacetyl cellulose, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, acrylic resin film, norbornene resin film, cycloolefin resin Examples of the resin film such as a film; and a laminate of two or more of these. The resin film may be uniaxially stretched or biaxially stretched. Among these, a polyester film is preferable from the viewpoints of thickness accuracy, surface smoothness, availability, and the like required as the film thickness is reduced. As the polyester film, a PET film is particularly preferable. The polyester film is preferably a biaxially stretched film from the viewpoint of dimensional stability and strength. Among these, a biaxially stretched PET film is preferable.

[Adhesive layer]
The pressure-sensitive adhesive that forms the pressure-sensitive adhesive layer of the pressure-sensitive adhesive film 2 is not particularly limited, and examples thereof include acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, polyester-based pressure-sensitive adhesives, and styrene-diene. It can be appropriately selected from known adhesives such as block copolymer adhesives. An adhesive can be used individually or in combination of 2 or more types.

  As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive can be preferably used because it has high adhesion reliability. The acrylic pressure-sensitive adhesive has an acrylic polymer as a pressure-sensitive adhesive component or main ingredient and, as necessary, an appropriate agent such as a crosslinking agent, a tackifier, a softener, a plasticizer, a filler, an anti-aging agent, or a colorant. Additives are included. Acrylic polymer is a polymer that has (meth) acrylic acid alkyl ester as the main component of monomer and can be copolymerized with (meth) alkyl ester as needed (copolymerizable monomer) Body). Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-Methylhexyl acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate , Dodecyl (meth) acrylate, tridecyl (meth) acrylate, (me ) Tetradecyl acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate (meta) ) Acrylic acid C1-20 alkyl ester [preferably (meth) acrylic acid C4-18 alkyl (linear or branched alkyl) ester] and the like. The (meth) acrylic acid alkyl ester can be appropriately selected according to the intended tackiness and the like.

  As the (meth) acrylic acid alkyl ester, from the viewpoint of lowering the Tg of the resulting acrylic polymer and improving the adhesive strength of the pressure-sensitive adhesive layer, the alkyl (meth) acrylate having an alkyl group having 4 to 14 carbon atoms. Esters are preferred. Examples of the (meth) acrylic acid alkyl ester having an alkyl group having 4 to 14 carbon atoms include butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, and (meth) acrylic acid. t-Butyl, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, and the like are preferable. Particularly preferred is butyl (meth) acrylate. These monomers may be used alone or in combination of two or more.

  Moreover, 50 mass% or more in the monomer component which comprises an acrylic polymer is preferable, and, as for content of the (meth) acrylic-acid alkylester which has a C4-C14 alkyl group, 80 mass% or more is more. Preferably, 90 mass% or more is more preferable. By setting it within the range, the adhesive strength in the above range can be easily obtained.

  Examples of the copolymerizable monomer copolymerizable with the (meth) alkyl ester include carboxyl groups such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid. -Containing monomers or anhydrides thereof; sulfonic acid group-containing monomers such as sodium vinyl sulfonate; aromatic vinyl compounds such as styrene and substituted styrene; cyano group-containing monomers such as acrylonitrile; ethylene, propylene, butadiene, etc. Olefins; vinyl esters such as vinyl acetate; vinyl chloride; amide group-containing monomers such as acrylamide, methacrylamide, N-vinylpyrrolidone, N, N-dimethyl (meth) acrylamide; hydroxyalkyl (meth) acrylate Contains hydroxyl groups such as glycerin dimethacrylate Monomers; amino group-containing monomers such as aminoethyl (meth) acrylate and (meth) acryloylmorpholine; imide group-containing monomers such as cyclohexylmaleimide and isopropylmaleimide; glycidyl (meth) acrylate and (meth) acrylic Epoxy group-containing monomers such as methyl glycidyl acid; isocyanate group-containing monomers such as 2-methacryloyloxyethyl isocyanate, triethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, ethylene glycol di (meta ) Acrylate, tetraethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, Pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, polyfunctional copolymerizable monomers such as divinylbenzene (multifunctional monomer) and the like. A copolymerizable monomer can be used individually or in combination of 2 or more types. As the copolymerizable monomer, a modifying monomer having a functional group such as a hydroxyl group or a carboxyl group can be suitably used.

  The (meth) acrylic acid alkyl ester copolymer preferably contains 0.1 to 20% by mass, and particularly preferably 1 to 10% by mass, of a modifying monomer having a functional group.

  The weight average molecular weight of the (meth) acrylic acid alkyl ester copolymer is preferably 200,000 to 2,000,000, particularly preferably 500,000 to 1,500,000. In addition, the weight average molecular weight in this specification is the value of polystyrene conversion measured by the gel permeation chromatography (GPC) method.

  As a crosslinking agent, what is necessary is just to react with the functional group which a (meth) acrylic-acid alkylester copolymer has, for example, an isocyanate type crosslinking agent, an epoxy-type crosslinking agent, an amine type crosslinking agent, a melamine type crosslinking agent, Examples include aziridine-based crosslinking agents, hydrazine-based crosslinking agents, aldehyde-based crosslinking agents, oxazoline-based crosslinking agents, metal alkoxide-based crosslinking agents, metal chelate-based crosslinking agents, metal salt-based crosslinking agents, and ammonium salt-based crosslinking agents. And an isocyanate-based cross-linking agent excellent in reactivity with a carboxyl group. A crosslinking agent can be used individually by 1 type or in combination of 2 or more types.

  The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. Examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate, and the like. And biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product with a low molecular active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, and the like. Among them, trimethylolpropane-modified aromatic polyisocyanate is preferable in terms of reactivity with the reactive group of the (meth) acrylic acid alkyl ester polymer. DOO, especially trimethylolpropane modified xylylene diisocyanate and trimethylolpropane-modified tolylene diisocyanate is preferable.

  It is preferable that the compounding quantity of a crosslinking agent is 0.1-20 mass parts with respect to 100 mass parts of (meth) acrylic-acid alkylester copolymers, and it is especially preferable that it is 1-10 mass parts. When the blending amount of the crosslinking agent is within the above range, the gel fraction of the pressure-sensitive adhesive described later can be easily controlled within a preferable range.

  Moreover, in order to improve the adhesive force of an adhesive layer, it is also preferable to add tackifying resin. In addition, by adding these tackifying resins, it is possible to increase the adhesive strength, tensile strength and tensile breaking strength, depending on the acrylic copolymer to be used, by appropriately adding a tackifying resin, Adhesive strength, tensile strength and tensile breaking strength can be adjusted. Examples of the tackifier resin to be added to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive film of the present invention include rosin resins such as rosin and rosin ester compounds; terpene resins such as diterpene polymers and α-pinene-phenol copolymers; Aliphatic (C5) and aromatic (C9) petroleum resins; other examples include styrene resins, phenolic resins, xylene resins, and the like. Among them, in the adhesive composition using acrylic adhesive, the adhesive tape is thin and excellent in adhesive strength, and the adhesive strength changes even when the adhesive tape is installed inside an electronic component and heated. It is preferable that it contains at least one selected from a rosin resin, a petroleum resin, and a styrene resin, more preferably a rosin resin, a petroleum resin, and a rosin resin and petroleum. It is particularly preferable to use a mixture of resins.

  The compounding amount of the tackifying resin is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass, and more preferably 50 to 100 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid alkyl ester copolymer. The amount is particularly preferably 60 parts by mass. When the amount of the tackifying resin is in the above range, the adhesive strength is excellent even when the adhesive tape is thin, and the adhesive strength is excellent even when the adhesive tape is installed and heated inside the electronic component. It becomes difficult to change.

  In addition, the pressure-sensitive adhesive layer may be a silane coupling agent, an antistatic agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a softening agent, a filler, a refractive index adjusting agent, a dye, a pigment, a rust inhibitor, etc. It may contain.

[Peeling film]
The release film is a film substrate in an adhesive film, and preferably has a release agent layer on the film substrate. In this case, the thickness of the release film mentioned above refers to the thickness of the film substrate.

  The thickness of the release agent layer is not particularly limited, but is preferably 0.01 μm or more and 2 μm or less, and particularly preferably 0.03 μm or more and 1 μm or less. When the thickness of the release agent layer is less than 0.01 μm, the function as the release agent layer may not be sufficiently exhibited depending on the material constituting the release agent layer. On the other hand, when the thickness of the release agent layer exceeds 2 μm, when the release film is wound into a roll, blocking may occur, which may cause problems in feeding.

  As film base materials, polyester films made of polyester such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyolefin films made of polyolefin such as polyethylene, polypropylene, polymethylpentene, plastic films such as polycarbonate film, polyvinyl acetate film, etc. Or a laminate composed of two or more of these material layers.

  The release agent layer is formed of, for example, a cured product of a release agent layer forming composition containing a release agent. The release agent layer forming composition is not particularly limited as long as it can provide the release agent layer with a function of releasing any layer laminated on the release agent layer from the release film. Examples of the release agent include silicone release agents, long-chain alkyl release agents, alkyd release agents, and the like. As a method for setting the peeling force within a predetermined range, it is preferable to use a silicone release agent as the release agent and an acrylic adhesive as the adhesive forming the adhesive layer.

  Examples of the silicone release agent include addition reaction type silicone, condensation reaction type silicone, and energy ray curable silicone. In order to adjust the peeling force, non-functional polydimethylsiloxane, phenyl-modified silicone, silicone resin, silica, or cellulose compound may be used as an additive.

  In addition to the adhesive film 2, the material of each layer used in the colored adhesive film 3 is as follows.

[Colored layer]
The colored layer is not particularly limited as long as it is colored in a color that matches or matches the color of the electronic component to which the colored adhesive tape is applied, but makes the spots on the appearance of the graphite sheet inconspicuous, From the viewpoint of imparting design properties, black is preferable.

  The colored layer preferably contains a coloring material and a binder resin. Examples of the binder resin include a urethane resin, an epoxy resin, a polyester resin, and a polyester urethane resin. These may be used alone or in combination of two or more. Among these, since the flexibility is excellent, the binder resin is preferably at least one of a polyester resin and a polyester urethane resin, and more preferably a polyester urethane resin. The binder resin preferably has a glass transition temperature (Tg) of −30 to 10 ° C.

  The colored layer is preferably cured by a curing agent. A hardening | curing agent is not specifically limited, According to binder resin, it selects suitably. When the binder resin is a polyester urethane resin, examples of the curing agent include an isocyanate curing agent. In addition, when a hydroxyl group or an isocyanate group exists in the polyester urethane resin, an amine curing agent may be used as the curing agent. These may be used alone or in combination of two or more.

  As the coloring material, known and commonly used pigments and dyes can be used. If the colored layer is black, for example, carbon black, if white, titanium oxide, calcium carbonate, barium sulfate, if yellow, yellow iron oxide, if red, brown, if blue, cyanine blue, if silver Examples include aluminum powder and mica titanium powder in the case of pearl. Among these, carbon black is preferable because of its excellent concealability. The content of the coloring material in the coloring layer is not particularly limited, and can be appropriately set according to the target concealing property. For example, the colored layer preferably includes a binder resin and a coloring material of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by weight of the binder resin. If the content of the coloring material exceeds 70 parts by mass, the adhesion with the roughened layer may be lowered, which is not preferable. A commercial item can also be used for the said coloring material, As a commercial item of a black coloring material, UTCO-591 black (made by Dainichi Seika Co., Ltd.) etc. are mention | raise | lifted, for example.

  The colored layer may further contain additives such as a transparent resin (medium), an antioxidant, an ultraviolet absorber, and a light stabilizer as necessary.

[Roughening layer]
The material of the roughening layer is not particularly limited as long as the arithmetic average roughness Ra, the average height Rc of the roughness curve element, and the 10-point average roughness Rzjis are in desired ranges. The roughened layer may be formed by a method of corona discharge treatment, sandblast treatment, a method of transferring the roughness of the roll surface by pressing the rough roll surface to the surface of the roughened layer, and the like. And Rzjis may be adjusted.

  The roughening layer preferably includes particles and a binder resin, more preferably includes at least one of inorganic particles and organic particles, and includes inorganic particles and a binder resin. Further preferred. The roughness and the like can be easily adjusted by adjusting the average particle diameter, blending amount, and the like of the inorganic particles and / or organic particles. The average particle diameter of the inorganic particles and / or organic particles may be larger than the thickness of the roughened layer. In the roughened layer 15, the inorganic particles may be exposed or the binder resin may be exposed. The average particle diameter of the inorganic particles is 50 nm or more and 10 μm or less.

  The average particle diameter is not particularly limited, but is measured by a Coulter counter method. For example, the peak top value measured by the Coulter counter method is used as the average particle size.

  The binder resin is not particularly limited, and examples thereof include a thermoplastic resin, a thermosetting resin, and a photocurable resin, and examples thereof include a urethane resin, an epoxy resin, a polyester resin, and a polyester urethane resin. These may be used alone or in combination of two or more. Among them, a thermoplastic resin is preferable because of excellent flexibility, and a urethane resin, a polyester resin, and a polyester urethane resin are preferable. In the case where the roughened layer contains particles, the binder resin is more preferably at least one of a polyester resin and a polyester urethane resin from the viewpoint of compatibility.

  The roughening layer may be cured with a curing agent. A hardening | curing agent is not specifically limited, According to binder resin, it selects suitably. When the binder resin is a polyester urethane resin, examples of the curing agent include an isocyanate curing agent. In addition, when a hydroxyl group or an isocyanate group exists in the polyester urethane resin, an amine curing agent may be used as the curing agent. These may be used alone or in combination of two or more. In addition, the roughened layer may contain additives such as an antioxidant, an ultraviolet absorber, and a light stabilizer, if necessary, in the same manner as that contained in the colored layer.

  [Method for producing adhesive film]

  Although the manufacturing process of the adhesive film which concerns on this embodiment is demonstrated below, it is not limited to this. FIG. 3 is a schematic view for explaining the production process of the pressure-sensitive adhesive film according to the present embodiment. In this embodiment, the adhesive film 2 is manufactured by a roll-to-roll method. The adhesive film 2 is manufactured in the atmosphere, for example. An arrow DR in the figure indicates the traveling direction of the film. The traveling direction DR corresponds to the long direction DL.

  The release film 30 is continuously unwound from the unwinding roll 211 by the rotation of the unwinding roll 211 and guided to the coating mechanism 220 through the guide roll 250a. A release agent layer is formed on the surface of the release film 30 (the surface on which the pressure-sensitive adhesive layer 20 is formed).

  The application mechanism 220 applies the coating liquid for the pressure-sensitive adhesive layer 20 onto the release film 30 that is fed from the unwinding roll 211. The release film 30 with the pressure-sensitive adhesive layer 20 is guided to the drying chamber 230 through the guide roll 250b, and is dried at a predetermined temperature, for example, for 10 seconds to 5 minutes. Thereby, the peeling film 30 with the adhesive layer 20 which has the peeling film 30 and the adhesive layer 20 is formed. The release film 30 with the pressure-sensitive adhesive layer 20 is guided to the pasting mechanism 240 via the guide roll 250c.

  The resin film 11 is attached to the adhesive layer 20 side of the release film 30 with the adhesive layer 20 guided to the attaching mechanism 240 by the attaching mechanism 240. For example, the release film 30 with the pressure-sensitive adhesive layer 20 is sandwiched between the roll 240b and the roll 240c, and the resin film 11 is fed out between the roll 240b and the roll 240c from the unwinding roll 240a.

  Thereby, the resin film 11 is bonded together to the adhesive layer 20, and the adhesive film 2 which has the peeling film 30, the adhesive layer 20, and the resin film 11 is formed. Thereafter, the adhesive film 2 is continuously wound around the winding roll 210 by the rotation of the winding roll 210 via the guide roll 250d.

  In addition, as a coating method in the coating mechanism 220, for example, any method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, or a gravure coating method may be applied.

  When the pressure-sensitive adhesive film 2 has the colored layer 12 and / or the roughened layer 15, the colored layer 12 and / or the roughened layer 15 is laminated on the resin film 11 after the pressure-sensitive adhesive film 2 is manufactured. Is done. Or the colored layer 12 and / or the roughening layer are laminated | stacked on the resin film 11 previously, and the peeling film 30 is affixed after that and the adhesive film 2 is manufactured.

  The method for laminating the colored layer 12 and / or the roughened layer 15 on the resin film 11 is not particularly limited. When the coating liquid of the colored layer 12 and / or the roughening layer 15 is ink, a method of laminating by printing is preferable. As a printing method, any one of known methods such as letterpress printing, flexographic printing, dry offset printing, gravure printing, gravure offset printing, offset printing, and screen printing may be applied. Among these, the gravure printing method is a preferable method because the pinholes are reduced by printing on the resin film 11 by being stacked 2 to 4 times and laminating.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc. In Table 1, the effect of the adhesive film which concerns on this embodiment is shown.

  [Example 1]

<Preparation of adhesive composition solution>
By copolymerizing 95.5 parts by weight of butyl acrylate, 3 parts by weight of vinyl acetate, 1 part by weight of 2-hydroxyethyl acrylate, and 0.5 parts by weight of acrylic acid, acrylic acid having a weight average molecular weight of 1000000 An ester copolymer is produced. Next, 25 parts by mass of hydrogenated rosin ester (Arakawa Chemical Industries, Pine Crystal KE-100, softening point: 100 ° C.) with respect to 100 parts by mass of this acrylic acid ester copolymer (in terms of solid content; the same applies hereinafter). 4 parts by mass of polymerized rosin ester (Arakawa Chemical Industries, Pencel D-135, softening point: 135 ° C.) and 24 parts by mass of petroleum resin (Mitsui Chemicals, FTR 6100, softening point: 95 ° C.) By mixing, an adhesive component was formed. The adhesive component was dissolved in toluene to prepare an adhesive solution having a solid concentration of 13% by mass.

<Preparation of colored layer coating solution>
As a coating solution for the colored layer, UTCO-591 black (NX) manufactured by Dainichi Seika Kogyo Co., Ltd., which is a urethane-based solid content concentration of 59% by mass, was used and diluted with ethyl acetate. The coating solution for the colored layer was adjusted to a solid content concentration of 10% by mass and a viscosity of 15 mPa · s.

<Preparation of coating solution for roughening layer>
The coating solution for the roughening layer was prepared by using silica fine particles (NIPSIL SS50B, manufactured by Tosoh Silica Co., Ltd., average particle size 2.1 μm) with respect to 100 parts by mass (converted to solid content) of polyester resin (Toyobo: Byron 20SS) as a binder resin. 22 parts by mass, 100 parts by mass of barium sulfate fine particles (manufactured by Sakai Chemical Industry Co., Ltd .: BMH average particle size 2.5 μm), and a toluene / methyl ethyl ketone (MEK) mixed solvent (toluene: MEK (mass ratio) = 50). : 50), the solid content concentration was adjusted to 20% by mass.

<Manufacture of adhesive film>
To 100 parts by mass of the solid content of the pressure-sensitive adhesive composition, 1 part by mass (corresponding to solid content) of trimethylolpropane-modified tolylene diisocyanate (manufactured by Nippon Polyurethane Co., Ltd.) is added as a crosslinking agent. (Solid content concentration 13 mass%) was obtained.

A release film in which one side of a polyethylene terephthalate film is release-treated with a silicone-based release agent (SP-PET251130 manufactured by Lintec Corporation, Ra on the lower surface 30d of the release film: 34 nm, Rc: 400 nm, Rzjis: 672 nm, Young's modulus of the release film: 4200 MPa , Thickness: 2.5 × 10 ⁻⁵ m, product of Young's modulus and thickness of release film: 0.105 MPa · m), and the thickness after drying is 2 μm on the release-treated surface Then, after the adhesive composition solution was applied with a knife coater, the obtained coating film was heat-treated at 90 ° C. for 1 minute to form an adhesive layer having a thickness of 2 μm on the release film. Thereafter, a polyethylene terephthalate film (Toray, ET2F51L, thickness 2 μm, Young's modulus 4200 MPa) as a resin film was bonded to the exposed surface side of the coating layer, and the obtained adhesive film was wound up in a roll shape.

  Next, the adhesive film wound up in a roll shape is cured for 7 days under the conditions of 23 ° C. and 50% RH, so that a release film (thickness: 25 μm) / adhesive layer (thickness: 2 μm) / resin film An adhesive film made of (thickness: 2 μm) was produced.

  Next, the pressure-sensitive adhesive film wound in a roll shape was unwound, and a colored layer coating solution was applied to the resin film surface by a gravure coater, followed by heat treatment, and a colored layer having a thickness of 1 μm was formed on the pressure-sensitive adhesive film. . Furthermore, after the coating solution for the roughened layer was applied to the colored layer surface with a gravure coater so that the thickness after drying was 1 μm, the obtained coating film was heat-treated at 90 ° C. for 1 minute, A roughened layer having a thickness of 1 μm was formed. Thereafter, release film (thickness: 25 μm) / adhesive layer (thickness: 2 μm) / resin film (thickness: 2 μm) / colored layer (thickness: 1 μm) / roughened layer (thickness: 1 μm) The pressure-sensitive adhesive film with a colored layer was wound into a roll.

<Measurement of Young's modulus>
The Young's modulus of the release film or resin film was measured in accordance with JIS K-7127 (1999) by selecting 200 mm / min as the test speed.

<Measurement of thickness>
The thickness of each layer was measured using a film thickness meter (film thickness meter Digimicro MH-15M manufactured by Nikon Corporation).

<Measurement of peeling force for adhesive layer of release film>
The pressure-sensitive adhesive film was cut into a width of 50 mm and a length of 150 mm to prepare a sample, and left for 1 hour under the conditions of 23 ° C. and 50% RH. The surface opposite to the release film of this sample is fixed to non-alkali glass (Corning Corp., Eagle XG) with a double-sided tape, and the release film is used with a tensile tester (Orientec Corp., Tensilon) The peel strength at the time of peeling under the conditions of a peeling speed of 300 mm / min and a peeling angle of 180 degrees was measured. Conditions other than those described here were measured according to JIS Z0237: 2009. Next, the peel force (mN / 25 mm) was calculated from the above peel strength by the following formula (W is the width of the test piece (mm): 50).
Peeling force (mN / 25mm) = Peeling strength (mN / 50mm) × 25 ÷ W (formula)

<Measurement of adhesive strength of adhesive tape to stainless steel plate>
The adhesive film was cut to prepare a sample having a width of 25 mm and a length of 250 mm. The release film was peeled off from this sample, and the sample with the pressure-sensitive adhesive layer exposed was attached to stainless steel (SUS304) using a 2 kg rubber roller. Then, after leaving for 24 hours under the conditions of 23 ° C. and 50% RH, using a tensile tester (Orientec, Tensilon), according to JISZ0237: 2009, peeling speed of 300 mm / min, peeling angle of 180 °. The adhesive strength (N / 25 mm) was measured under the following conditions.

<Surface roughness measurement>
The average height Rc of the roughness curve element on the lower surface 30d of the release film was measured according to JIS B 0601-2001 using a contact surface roughness meter (product name “SV3000S4” manufactured by Mitutoyo Corporation).

<Peelability of release film>
A: The release film was peeled off from the pressure-sensitive adhesive layer without any problem.
C: The release film was difficult to peel from the pressure-sensitive adhesive layer.

<Adaptability of adhesive tape>
In the pressure-sensitive adhesive film, a peeling start point is formed between the release film and the pressure-sensitive adhesive layer, and the release film is peeled off from the pressure-sensitive adhesive layer. Under conditions of an environmental temperature of 23 ° C. and a humidity of 50%, a graphite sheet is rolled with a 2 kg roller. One reciprocating pressure was applied. It observed visually and evaluated by the following references | standards.
A: After peeling off the release film, no wrinkles or slack occurred on the adhesive tape, and there was no air bubbles even after application.
C: Wrinkles and slack are generated in the adhesive tape when the release film is peeled off. And / or wrinkles / sagging occurred on the adhesive tape after application.

<Processability of adhesive film>
In the production process of the adhesive film, the following criteria were used for evaluation.
A: Processing was possible without any problems.
C: Wrinkles and / or slack occurred during conveyance in some processes, resulting in problems in processing.

  In Example 1, all of peeling suitability, sticking suitability, and processing suitability were “A”.

  [Example 2]

The release film was a release film obtained by removing one surface of a polyethylene terephthalate film having a thickness of 3.8 × 10 ⁻⁵ m with a silicone-based release agent (SP-PET381130 manufactured by Lintec Corporation, Ra: 34 nm of the lower surface 30d of the release film, Rc: 320 nm, Rzjis: 672 nm, release film Young's modulus: 4200 MPa, thickness: 3.8 × 10 ⁻⁵ m, product of release film Young's modulus and thickness: 0.160 MPa · m) In the same manner as in Example 1, a pressure-sensitive adhesive film with a colored layer was produced.

  In Example 2, all of peeling suitability, sticking suitability, and processing suitability were “A”.

  [Example 3]

  A pressure-sensitive adhesive film with a colored layer was produced in the same manner as in Example 1 except that no roughening layer was provided.

  In Example 3, all of the peeling suitability, the sticking suitability, and the processing suitability were “A”.

  [Example 4]

The release film was a release film in which one side of a polyethylene terephthalate film having a thickness of 2.5 × 10 ⁻⁵ m was subjected to a release treatment with a silicone-based release agent (SP-PET 251031, manufactured by Lintec Corporation, Ra of the lower surface 30d of the release film: 34 nm, Rc: 400 nm, Rzjis: 672 nm, release film Young's modulus: 4200 MPa, thickness: 2.5 × 10 ⁻⁵ m, product of release film Young's modulus and thickness: 0.105 MPa · m) In the same manner as in Example 1, a pressure-sensitive adhesive film with a colored layer was produced.

  In Example 4, all of peelability, sticking suitability, and processing suitability were “A”.

  [Example 5]

The release film was a release film in which one side of a polyethylene terephthalate film having a thickness of 2.5 × 10 ⁻⁵ m was subjected to a release treatment with a silicone release agent (SP-PET252120 manufactured by Lintec Corporation, Ra on the lower surface 30d of the release film: 34 nm, Rc: 400 nm, Rzjis: 672 nm, release film Young's modulus: 4200 MPa, thickness: 2.5 × 10 ⁻⁵ m, product of release film Young's modulus and thickness: 0.105 MPa · m) In the same manner as in Example 1, a pressure-sensitive adhesive film with a colored layer was produced.

  In Example 5, all of the peelability, the sticking suitability, and the processing suitability were “A”.

  As described above, there was no evaluation corresponding to “C” in any of Examples 1 to 5.

  [Comparative Example 1]

The release film was a release film in which one side of a polyethylene terephthalate film having a thickness of 7.5 × 10 ⁻⁵ m was subjected to a release treatment with a silicone-based release agent (SP-PET751130 manufactured by Lintec Corporation, Rc of the lower surface 30d of the release film: 290 nm, Color is the same as in Example 1 except that the Young's modulus of the release film is 4200 MPa, the thickness is 7.5 × 10 ⁻⁵ m, and the product of the Young's modulus and the thickness of the release film is 0.315 MPa · m). A pressure-sensitive adhesive film with a layer was produced.

  In Comparative Example 1, the peelability and the processability were “A”, but the product of the Young's modulus and the thickness of the release film was too high, so that the adhesive tape was wrinkled and loosened when the release film was peeled off. As a result, the sticking suitability became “C”.

  [Comparative Example 2]

The release film was a release film in which one side of a polyethylene terephthalate film having a thickness of 7.5 × 10 ⁻⁵ m was subjected to a release treatment with a silicone-based release agent (SP-PET752150 manufactured by Lintec Corporation, Rc of the lower surface 30d of the release film: 290 nm, Color is the same as in Example 1 except that the Young's modulus of the release film is 4200 MPa, the thickness is 7.5 × 10 ⁻⁵ m, and the product of the Young's modulus and the thickness of the release film is 0.315 MPa · m). A pressure-sensitive adhesive film with a layer was produced.

  In Comparative Example 2, the suitability for processing was “A”, but the peelability was too high because the peel strength was too high, and the peelability was “C”. Furthermore, since the product of the Young's modulus and the thickness of the release film was too high, wrinkles and slack occurred in the adhesive tape when the release film was released, and the sticking suitability was “C”.

  [Comparative Example 3]

The release film was a release film in which one side of a polyethylene terephthalate film having a thickness of 3.8 × 10 ⁻⁵ m was subjected to release treatment with a silicone release agent (SP-PET382150 manufactured by Lintec Corporation, Rc: 320 nm of the lower surface 30d of the release film, Color is the same as in Example 1 except that the Young's modulus of the release film is 4200 MPa, the thickness is 3.8 × 10 ⁻⁵ m, and the product of the Young's modulus and thickness of the release film is 0.160 MPa · m). A pressure-sensitive adhesive film with a layer was produced.

  In Comparative Example 3, the workability was “A”, but the peelability was too high because the peel force was too high, and the peelability was “C”.

  As mentioned above, although embodiment of this invention was described, this invention is not limited only to the above-mentioned embodiment, Of course, a various change can be added.

DESCRIPTION OF SYMBOLS 1 ... Colored adhesive tape 2 ... Adhesive film 3, 53 ... Colored adhesive film 4 ... Adhesive tape 11 ... Resin film 11u ... Upper surface 12 ... Colored layer 15 ... Roughening layer 15u ... Upper surface 20 ... Adhesive layer 20a, 20b ... Adhesive Surface 30 ... Release film 30d ... Lower surface 100 ... Graphite sheet 101 ... Double-sided tape 102 ... Housing 210 ... Winding roll 211, 240a ... Unwinding roll 220 ... Application mechanism 230 ... Drying chamber 240 ... Pasting mechanism 240b, 240c ... Roll 250a , 250b, 250c, 250d ... guide roll

Claims (8)

A release film;
A pressure-sensitive adhesive tape comprising: a resin film; and a pressure-sensitive adhesive layer having a first pressure-sensitive adhesive surface bonded to the resin film and a second pressure-sensitive adhesive surface bonded to the release film.
The product of Young's modulus (MPa) and thickness (m) at 25 ° C. of the release film is 0.3 MPa · m or less,
The total thickness of the resin film and the pressure-sensitive adhesive layer is 10 μm or less,
Peel force of the release film to said second adhesive surface, in a peeling rate of 300 mm / min, Ri 40 mN / 25 mm der less,
The average height (Rc) of the surface roughness curve element on the lower surface of the release film that is opposite to the pressure-sensitive adhesive layer of the release film and contacts the resin film during winding is 500 nm or less,
Adhesive film dynamic friction coefficient with respect to the lower surface of the release film of the outermost surface, Ru der 0.2 to 5 of the resin film. The pressure-sensitive adhesive film according to claim 1,
The release film has a Young's modulus of 500 MPa or more at 25 ° C. The pressure-sensitive adhesive film according to claim 1 or 2,
The resin film is an adhesive film having a Young's modulus of 500 MPa or more at 25 ° C. The pressure-sensitive adhesive film according to any one of claims 1 to 3 ,
The thickness of the resin film is 1 μm or more and 6 μm or less. The pressure-sensitive adhesive film according to any one of claims 1 to 4 ,
The pressure-sensitive adhesive layer has a thickness of 1 μm or more and 5 μm or less. The pressure-sensitive adhesive film according to any one of claims 1 to 5 ,
In the pressure-sensitive adhesive tape, the pressure-sensitive adhesive force to the stainless steel plate (peeling angle 180 °, peeling speed 300 mm / min) is 1 N / 25 mm or more and 2.5 N / 25 mm or less. The pressure-sensitive adhesive film according to any one of claims 1 to 6,
The thickness of the release film is 2 × 10 ⁻⁵ m or more and 3 × 10 ⁻⁵ m or less.
Adhesive film. The pressure-sensitive adhesive film according to any one of claims 1 to 7,
The said adhesive layer and the said resin film are affixed on the surface of a graphite sheet.

Images