Film, wound body, connection structure, and method for manufacturing connection structure

Abstract

A film provided with: a long release film; the plurality of adhesive membranes are arranged on the stripping film; and a groove formed on the surface of the release film on the side of the plurality of adhesive films and extending along the outer edge of each of the plurality of adhesive films, the groove having a width of 15 [mu] m or more.

Description

Technical Field

[0001] The present invention relates to a film, a wound body, a connection structure and a method for manufacturing the connection structure. Background Art

[0002] In recent years, the high functionality, miniaturization, thinness, and sophistication of design of devices such as smartphones, personal computers, headphones, smart watches, and wearable devices have continued to develop, and the high functionality and complexity of sensors, parts, substrates, etc. mounted on these devices have also developed. As a result, the use of materials with low heat resistance for part or all of sensors, parts, substrates, etc., or the use of sensors, parts, substrates, etc. with low heat resistance on devices, or the use of other components at high temperatures close to sensors, parts, substrates, etc. with low heat resistance has also increased. In addition, "connection" includes the meanings of bonding, installation, and mounting. As a result, the need for technology to connect other components only at one or more specified locations such as sensors, parts, substrates, etc. has begun. Moreover, the location where other components are connected to sensors, parts, substrates, etc. varies depending on the type of device, etc.

[0003] Previous technical literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2018 / 066411 Summary of the invention

[0006] Technical issues to be solved by the invention

[0007] Therefore, it is conceivable to use a film having a plurality of adhesive sheets provided on a release film as described in Patent Document 1, and to attach the adhesive sheets only at one or more predetermined positions of sensors, parts, substrates, etc. Such a film is generally used as a winding body wound around a winding core.

[0008] However, the adhesive forming the adhesive film sheet is not completely cured, so as time goes by, it attempts to deform in a manner that expands along the surface of the release film. In addition, regarding the winding of the film onto the core, since a prescribed tension is applied to the release film to wind the film onto the core, the film is in a state of being pressurized toward the core (center) in the winding body. This pressure is generated by the winding film, and is therefore also referred to as winding pressure. The winding pressure increases toward the center. Therefore, the adhesive film sheet clamped from the inner layer side (core side) and the outer layer side (the side opposite to the core) by the release film is pressed from the inner layer side and the outer layer side by the release film in an attempt to deform into expanding along the surface of the release film.

[0009] If the adhesive film sheet is deformed to spread along the surface of the release film, the adhesive film sheet protrudes from the adhesive surface, and the yield rate is likely to be reduced. In particular, in anisotropic conductive films, since the adhesive forming the adhesive film sheet contains a liquid component resin, the deformation of the adhesive film sheet along the surface of the release film becomes significant, and thus the yield rate is more likely to be reduced.

[0010] Therefore, an object of one aspect of the present invention is to provide a film, a wound body, a connected structure, and a method for producing the connected structure, which are capable of suppressing the expansion of an adhesive film sheet.

[0011] Means for solving technical problems

[0012] The present inventors have conducted intensive studies on the above-mentioned problems and have found that the spreading of the adhesive film can be suppressed by forming grooves on the surface of the release film and setting the groove width to a predetermined value or more. The present invention has been completed based on the above-mentioned findings.

[0013] That is, the film involved in one aspect of the present invention comprises: a long strip of release film; a plurality of adhesive film sheets arranged on the release film; and a groove formed on the surface of the plurality of adhesive film sheets of the release film and extending along the outer edge of each of the plurality of adhesive film sheets, the width of the groove being greater than 15 μm.

[0014] In this film, a plurality of adhesive film sheets are provided on the peeling film, and therefore each of the plurality of adhesive film sheets tries to spread along the surface of the peeling film. However, a groove is formed on the surface of the peeling film on the side of the plurality of adhesive film sheets and extends along the outer edge of each of the plurality of adhesive film sheets, and the width of the groove is 15 μm or more. Therefore, the groove blocks the spread of each of the plurality of adhesive film sheets along the surface of the peeling film, and each of the plurality of adhesive film sheets can be suppressed from spreading across the groove.

[0015] The groove may be located outside the outer edge of each of the plurality of adhesive film sheets. In this film, since the groove is located outside the outer edge of each of the plurality of adhesive film sheets, diffusion of each of the plurality of adhesive film sheets can be further suppressed.

[0016] The depth of the groove may be 10% or more of the thickness of the release film. In this film, by making the depth of the groove 10% or more of the thickness of the release film, the width of the groove can be easily set to 15 μm or more, and the path for each of the plurality of adhesive film sheets to cross the groove can be made longer. Thus, each of the plurality of adhesive film sheets can be further prevented from crossing the groove and expanding.

[0017] The depth of the groove may be 85% or less of the thickness of the release film. In this film, when the depth of the groove is 85% or less of the thickness of the release film, the release film can be prevented from breaking.

[0018] The depth of the groove may be 20% or more of the thickness of the adhesive film sheet surrounded by the groove among the plurality of adhesive film sheets. In the film, by making the depth of the groove 20% or more of the thickness of the adhesive film sheet surrounded by the groove, the path for each of the plurality of adhesive film sheets to cross the groove can be made longer. Thus, each of the plurality of adhesive film sheets can be further prevented from expanding across the groove.

[0019] The depth of the groove may be 100% or less of the thickness of the adhesive film sheet surrounded by the groove among the plurality of adhesive film sheets. In this film, the groove can be easily formed by making the depth of the groove 100% or less of the thickness of the adhesive film sheet surrounded by the groove.

[0020] The adhesive forming each of the plurality of adhesive film sheets may have a multilayer structure. In the film, the adhesive forming each of the plurality of adhesive film sheets has a multilayer structure, whereby each of the plurality of adhesive film sheets is easily expanded. However, as described above, since the groove has a width of 15 μm or more, each of the plurality of adhesive film sheets can be suppressed from expanding across the groove.

[0021] The curing degree of the adhesive forming each of the plurality of adhesive film sheets can be 80% or more as measured by differential scanning calorimetry at 150° C. for 10 seconds. In the film, the curing degree of the adhesive forming each of the plurality of adhesive film sheets is 80% or more as measured by differential scanning calorimetry at 150° C. for 10 seconds, so that the influence of heat on other than the connection portion can be reduced.

[0022] The plurality of adhesive film sheets can be separated from each other. In the film, the plurality of adhesive film sheets can be separated from each other, so that the adhesive film sheet can be attached to the adhesive surface without affecting the adjacent adhesive film sheets. Thus, the adhesive film sheet can be easily attached to the adhesive surface.

[0023] A plurality of adhesive film pieces can be separated from the end edge of the peeling film in the width direction of the peeling film. In the film, by separating the plurality of adhesive film pieces from the end edge of the peeling film in the width direction of the peeling film, when the end of the peeling film interferes with other components, the adhesive film piece can be prevented from peeling off from the peeling film.

[0024] The plurality of adhesive film sheets may be arranged in a row along the long side direction of the release film. In this film, the adhesive film sheets can be easily attached by arranging the plurality of adhesive film sheets in a row along the long side direction of the release film.

[0025] At least one of the plurality of adhesive sheets may have a hole. In this film, since at least one of the plurality of adhesive sheets has a hole, for example, the adhesive sheet can be appropriately attached to a portion having a portion in the center where the adhesive sheet is not to be attached.

[0026] The plurality of adhesive film sheets may have the same shape. In this film, the plurality of adhesive film sheets have the same shape, so that the adhesive film sheets can be effectively attached to the plurality of adhesive surfaces having the same shape continuously or simultaneously.

[0027] The adhesive film may have conductivity. In the film, the adhesive film has conductivity, so that two components connected via the adhesive film can be electrically connected.

[0028] The adhesive film may contain conductive particles. In this film, the adhesive film contains conductive particles, so that conductivity can be easily imparted to the adhesive film.

[0029] A wound body according to one aspect of the present invention includes any one of the above-mentioned films and a winding core around which the film is wound.

[0030] In the winding body, since any of the above-mentioned films is wound on the core, a winding pressure that pressurizes the core (center) is generated on the film. Therefore, the adhesive film sheet clamped from the inner layer side (core side) and the outer layer side (the side opposite to the core) by the release film is pressed from the inner layer side and the outer layer side by the release film in an attempt to deform and unfold along the surface of the release film. However, the film has a groove formed on the surface of the multiple adhesive film sheets on the release film and extending along the outer edges of each of the multiple adhesive film sheets, and the width of the groove is 15μm or more. Therefore, by preventing the expansion of each of the multiple adhesive film sheets along the surface of the release film by the groove, it is possible to suppress the expansion of each of the multiple adhesive film sheets across the groove.

[0031] A connection structure according to one aspect of the present invention includes a first member having a first adhesive surface, a second member having a second adhesive surface, and any one of the above-described adhesive films connecting the first adhesive surface and the second adhesive surface.

[0032] In this connection structure, since the first member and the second member are connected by any of the above-mentioned adhesive films, it is possible to obtain a connection structure in which protrusion of the adhesive film from the first member and the second member is suppressed.

[0033] A method for manufacturing a connection structure according to one aspect of the present invention includes: a preparation step of preparing any of the above-mentioned films; and a connection step of connecting a first adhesive surface of a first member and a second adhesive surface of a second member via an adhesive sheet of the film.

[0034] In this method of manufacturing a connection structure, since the first adhesive surface of the first member and the second adhesive surface of the second member are connected via the adhesive film sheet of any of the above films, a connection structure can be manufactured in which protrusion of the adhesive film sheet from the first and second members is suppressed.

[0035] Effects of the Invention

[0036] According to the present invention, it is possible to suppress the expansion of the adhesive film. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a plan view showing an example of a part of the film according to the present embodiment.

[0038] Figure 2 It is a perspective view showing a wound body according to the present embodiment.

[0039] Figure 3 It means along Figure 1 A cross-sectional view showing an example of a cross section taken along line III-III is shown.

[0040] Figure 4 It means along Figure 1 A cross-sectional view showing another example of a cross section taken along line III-III is shown.

[0041] Figure 5 It means along Figure 1 A cross-sectional view showing another example of a cross section taken along line III-III is shown.

[0042] Figure 6 It is a top view showing an example of a part of a film.

[0043] Figure 7 middle, Figure 7 (a) Figure 7 (b) and Figure 7 (c) is a plan view showing another example of a part of the film.

[0044] Figure 8 It is a top view showing an example of a part of a film.

[0045] Fig. 9 It is a top view showing an example of a part of a film.

[0046] Fig.10 1 is a flowchart showing a method for producing a film according to the present embodiment.

[0047] Fig.11 middle, Fig.11 (a) Fig.11 (b) Fig.11 (c) and Fig.11 (d) is used to illustrate Figure 1 A cross-sectional view of the film manufacturing method shown.

[0048] Fig.12 middle, Fig.12 (a) Fig.12 (b) Fig.12 (c) and Fig.12 (d) is used to illustrate Figure 1 A perspective view of the film manufacturing method shown.

[0049] Fig.13 It is a cross-sectional view showing a connection structure according to the present embodiment.

[0050] Fig.14 1 is a flowchart showing a method for producing a connection structure according to the present embodiment.

[0051] Fig.15 Yes means Fig.14 Flow chart of the connection process shown.

[0052] Fig.16 It is used to illustrate Fig.14 A schematic process diagram of the connection process is shown.

[0053] Fig.17 This is a schematic diagram of the observation surface of Example 1.

[0054] Fig.18 It is a schematic diagram of the observation surface of Example 2.

[0055] Fig.19 It is a schematic diagram of the observation surface of Example 3.

[0056] Fig. 20 This is a schematic diagram of the observation surface of Example 4.

[0057] Fig.21 This is a schematic diagram of the observation surface of Comparative Example 1.

[0058] Fig. 22 This is a table showing the observation results of Examples 1 to 4 and Comparative Example 1. DETAILED DESCRIPTION

[0059] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. In addition, in the accompanying drawings, the same or equivalent parts are marked with the same symbols, and repeated descriptions are omitted. In addition, in the accompanying drawings, the dimensional ratios are appropriately changed to facilitate understanding of the description.

[0060] [membrane]

[0061] like Figure 1 As shown, the film 1 comprises: a long (strip-shaped) release film 2; a plurality of adhesive film sheets 3 provided on the release film 2; and a groove 4 formed on a surface 2a of the release film 2 on the side of the plurality of adhesive film sheets 3 and extending along the outer edge 3a of each of the plurality of adhesive film sheets 3 (see Figure 3 to Figure 5 ). In addition, Figure 2 As shown, the film 1 is made into a roll 15 wound around a core 14 for storage, transportation, etc.

[0062] (Release film)

[0063] The release film 2 is attached to a plurality of adhesive film sheets 3 to support the plurality of adhesive film sheets 3. The raw material of the release film 2 can be, for example, polyethylene terephthalate (PET), polyethylene, polypropylene, etc. The release film 2 can contain any filler. In addition, the surface of the release film 2 can be subjected to a release treatment, a plasma treatment, an antistatic treatment, etc.

[0064] When the adhesive film sheet 3 is attached to the adhesive surface (not shown) of the adhesive object (not shown) with high precision, it is preferable to determine the position of the adhesive film sheet 3 in the film 1. For example, the peeling film 2 may have an alignment mark for determining the position of the adhesive film sheet 3 in the film 1, and the position of the adhesive film sheet 3 is determined based on the alignment mark. In addition, the position of the adhesive film sheet 3 in the film 1 may be determined by detecting a specific configuration of the adhesive film sheet 3 in the film 1. Therefore, it is considered that the adhesive film sheet 3 in the film 1 may be detected by the camera device 33 (refer to Fig.16 ) detects the position of the adhesive film sheet 3 in the film 1. However, considering that the adhesive film sheet 3 is attached to the adhesive surface later, it is preferable to arrange the imaging device 33 on the side of the release film 2 opposite to the adhesive film sheet 3.

[0065] Therefore, the release film 2 may have light transmittance so that the position of the adhesive film piece 3 can be detected from the release film 2 side by the imaging device 33 .

[0066] In this case, the transmittance of the release film 2 can be set to 15% or more and 100% or less, preferably 15% or more and 99% or less, and more preferably 16% or more and 98% or less.

[0067] The transmittance of the release film 2 can be measured as follows: The release film cut into 50 mm×50 mm squares is placed on a haze meter (eg, NDH-5000, manufactured by NIPPON DENSHOKU INDUSTRIES Co., Ltd.) and the total light transmittance is measured.

[0068] The haze value of the release film 2 can be 3% or more and 100% or less, preferably 3% or more and 99% or less, and more preferably 4% or more and 99% or less.

[0069] The haze value of the release film 2 can be measured as follows: The release film cut into 50 mm×50 mm squares is placed on a haze meter (eg, NDH-5000, manufactured by NIPPON DENSHOKU INDUSTRIES Co., Ltd.) and the haze value is measured.

[0070] (Adhesive film)

[0071] Each of the plurality of adhesive film sheets 3 (hereinafter, also referred to as "adhesive film sheets 3") connects the first component and the second component as bonding objects. Therefore, from the viewpoint of easily achieving a good connection, the adhesive film sheets 3 may have the same thickness. And, from the viewpoint of easily achieving a good connection, the adhesive film sheets 3 may have a flat surface. That is, the surface of the adhesive film sheet 3 on the side of the release film 2 and the surface of the adhesive film sheet 3 on the side opposite to the release film 2 may be flat. The same thickness means that in addition to being exactly the same thickness, a thickness error of about ±10% is included. A flat surface means that in addition to being a completely flat surface, an error in flatness of about ±10% is included. As Figure 3 to Figure 5 As shown, the adhesive film 3 has a film-like adhesive 6 .

[0072] The adhesive 6 forming the adhesive film sheet 3 can be, for example, a multilayer structure. The multilayer structure may include, for example, a structure in which adhesive films of different components are applied one on top of another or a structure in which different adhesive films are bonded together.

[0073] As the adhesive 6 forming the adhesive film 3, for example, thermoplastic resin, thermosetting resin, mixed system of thermoplastic resin and thermosetting resin, and photocurable resin are used. As thermoplastic resin, for example, styrene resin system and polyester resin system are used. As thermosetting resin, for example, epoxy resin system, acrylic resin system and silicone resin system are used. When using thermoplastic resin and thermosetting resin, heating and pressurization are usually required. This is to make the resin flow in the thermoplastic resin and obtain the adhesion with the adherend, and also to further carry out the curing reaction of the resin in the thermosetting resin. In addition, photocurable resin does not need to be heated when curing, so it is useful when connection is required at low temperature.

[0074] From the viewpoint of minimizing the influence of heat on other than the connection part, as the adhesive 6 forming the adhesive film 3, for example, a resin having a degree of curing of 80% or more under the conditions of 150°C and 10 seconds, 80% or more under the conditions of 160°C and 10 seconds, 80% or more under the conditions of 170°C and 10 seconds, 80% or more under the conditions of 180°C and 10 seconds, 80% or more under the conditions of 200°C and 10 seconds, 80% or more under the conditions of 210°C and 10 seconds, or 80% or more under the conditions of 230°C and 10 seconds can be used. The most preferred resin properties can also be selected according to the reliability level required for the final device. The degree of curing measured by the differential scanning calorimetry can be calculated from the difference between the residual calorific value of the cured resin and the calorific value of the uncured resin using a differential scanning calorimeter (for example, DSC Q-2500 manufactured by TA Instruments).

[0075] The adhesive film sheet 3 may be conductive or non-conductive. For example, the adhesive film sheet 3 may be formed of a conductive adhesive film, a non-conductive adhesive film, or a mixed adhesive film having a conductive adhesive region and a non-conductive adhesive region in the thickness direction or surface direction of the adhesive film. Furthermore, the adhesive film sheet 3 may be composed of two layers, namely, a first adhesive layer and a second adhesive layer, or may be composed of three or more layers, namely, a first adhesive layer, a second adhesive layer, and a third adhesive layer. The first adhesive layer, the second adhesive layer, and the third adhesive layer may be conductive or non-conductive.

[0076] The conductive adhesive film forming the adhesive film sheet 3 may have, for example, isotropic conductivity or anisotropic conductivity. Figure 4 As shown, conductivity can be easily obtained by including the conductive particles 7. The conductive particles 7 are contained in the binder 6, for example.

[0077] As the conductive particles 7, for example, metal particles such as Au, Ag, Ni, Cu, Pd, solder, and carbon particles are used. Furthermore, the conductive particles 7 may be particles obtained by coating the surface of transition metals such as Ni and Cu with precious metals such as Au, Ag, and Pd. Furthermore, the conductive particles 7 may be particles obtained by forming a conductive layer on the surface of non-conductive particles such as glass, ceramics, and plastics by coating the surface of non-conductive particles with a conductive material. The conductive particles 7 may also be particles whose outermost layer is composed of precious metals, particles using hot molten metal particles, and the like.

[0078] As the conductive particles 7, for example, conductive particles having an isotropic shape such as a roughly spherical shape can be used. Conductive particles having an isotropic shape refer to, for example, conductive particles having a roughly symmetrical shape. From the viewpoint of being able to achieve good connection characteristics even when an oxide film is formed on the electrode surface of the connected component, the conductive particles 7 may, for example, be conductive particles having anisotropic shapes such as dendrites (also called tree-like), flakes (also called flat plates, scales). Conductive particles having an anisotropic shape refer to, for example, conductive particles having anisotropic shapes, that is, conductive particles that do not have a roughly point-symmetrical shape (isotropic shape). By having an anisotropic shape, the conductive particles 7 can penetrate the oxide film on the electrode surface and achieve good connection characteristics. The conductive particles 7 can be used alone or in combination of two or more.

[0079] As the mixed adhesive film forming the adhesive film sheet 3, for example, Figure 5As shown, the conductive adhesive region 8 and the non-conductive adhesive region 9 may be disposed adjacent to each other on the release film 2. The conductive adhesive region 8 may contain conductive particles 7, for example, similar to the conductive adhesive film.

[0080] The plurality of adhesive film sheets 3 may be separated in the long side direction X of the release film 2, or may be connected in the long side direction X of the release film 2. Figure 1 As shown in FIG. 1 , in this embodiment, a plurality of adhesive film sheets 3 are separated in the longitudinal direction X of the release film 2. Figure 6 In the film 1 shown, a plurality of adhesive film sheets 3 may be connected in the longitudinal direction X of the release film 2 .

[0081] When the adjacent adhesive film pieces 3 are separated in the long side direction of the release film 2, the separation distance in the long side direction X of the adjacent adhesive film pieces 3 can be set to be 0.1 mm or more and 20 mm or less, or 0.1 mm or more and 15 mm or less, or 0.1 mm or more and 10 mm or less, or 0.1 mm or more and 8 mm or less, or 0.2 mm or more and 5 mm or less. If the separation distance in the long side direction X of the adjacent adhesive film pieces 3 is within the above range, when the adjacent adhesive film pieces 3 are attached to another component, the conveying distance of the film 1 can be shortened, and the film 1 can be effectively utilized to achieve low cost.

[0082] The shape of the adhesive film 3 is not particularly limited, and can be various shapes. For example, as the shape of the adhesive film 3, there can be cited circles such as a perfect circle and an ellipse, polygons such as a triangle and a square, stars, various marks and other complex shapes, etc. As quadrilaterals, there can be cited squares, rectangles, trapezoids, etc.

[0083] like Figure 7 (a) Figure 7 (b) and Figure 7 (c) As shown in the film 1, the adhesive film 3 may have a hole 3b. The hole 3b is a hole that is hollowed out (punched out) a part of the adhesive film 3. The shape, size, position, number, etc. of the hole 3b are not particularly limited. For example, the hole 3b may be similar to the shape of the adhesive film 3, or it may be dissimilar to the shape of the adhesive film 3. As the shape of the hole 3b, there may be cited complex shapes such as circles such as a perfect circle and an ellipse, polygons such as a triangle and a square, a star, various marks, etc. As quadrilaterals, there may be cited squares, rectangles, trapezoids, etc. The position of the hole 3b may be the central part of the adhesive film 3, or it may be the end of the adhesive film 3. The number of holes 3b formed on one adhesive film 3 may be one, or it may be more than two. In the case where a plurality of holes 3b are formed on one adhesive film 3, the shape, size, etc. of each hole 3b may be the same, or it may be different. Figure 7The adhesive film 3 shown in (a) may have a quadrilateral outer shape, and a quadrilateral hole 3 b similar to the outer shape of the adhesive film 3 is formed in the center thereof. Figure 7 The adhesive film 3 shown in (b) may have a circular outer shape, and a circular hole 3 b similar to the outer shape of the adhesive film 3 is formed in the center thereof. Figure 7 The adhesive film 3 shown in (c) may have a quadrilateral outer shape, and a circular quadrilateral hole 3b is formed in the center thereof.

[0084] The plurality of adhesive film sheets 3 may be arranged in a row along the long side direction X of the release film 2, or may be arranged in a plurality of rows along the long side direction X of the release film 2. In addition, when the plurality of adhesive film sheets 3 are arranged in a row along the long side direction X of the release film 2, only the plurality of adhesive film sheets 3 arranged in a row are provided on the release film 2. When the plurality of adhesive film sheets 3 are arranged in a row along the long side direction X of the release film 2, the plurality of adhesive film sheets 3 may be arranged in a row as shown in FIG. Figure 1 As shown in the film 1, the central part of the width direction Y of the release film 2 can also be arranged as Figure 8 As in the film 1 shown in FIG. 1 , the peeling film 2 is arranged at a position shifted (offset) from the center portion in the width direction Y of the peeling film 2 .

[0085] The plurality of adhesive films 3 may be of the same shape or may be of the same shape. Fig. 9 In the case where a plurality of adhesive film sheets 3 are in different shapes, all adhesive film sheets 3 may be in different shapes, or adhesive film sheets 3 in different shapes and adhesive film sheets 3 in the same shape may be mixed.

[0086] A plurality of adhesive film pieces 3 can be separated from the end edge of the release film 2 in the width direction Y of the release film 2. At this time, the separation distance between the end edge of the release film 2 in the width direction Y of the release film 2 and the adhesive film piece 3 closest to the end edge can be set to be greater than 0.1 mm and less than 20 mm, can be greater than 0.1 mm and less than 15 mm, can be greater than 0.1 mm and less than 10 mm, can be greater than 0.1 mm and less than 8 mm, can be greater than 0.2 mm and less than 5 mm.

[0087] (groove)

[0088] like Figure 1 and Figure 3 to Figure 5As shown, the groove 4 is formed on the surface 2a of the release film 2 on the side of the plurality of adhesive film sheets 3, and does not reach the back surface 2b of the release film 2 on the side opposite to the plurality of adhesive film sheets 3. That is, the groove 4 is recessed from the surface 2a of the release film 2 toward the thickness direction Z of the film 1 orthogonal to the long side direction X and the width direction Y, so that the groove 4 does not reach the back surface 2b of the release film 2 on the side opposite to the plurality of adhesive film sheets 3. The groove 4 is also called a half-cut line.

[0089] As long as the groove 4 extends along the outer edge 3a of each of the plurality of adhesive films 3, it may extend in a solid line or in a dotted line. The groove 4 extending in a solid line means that the groove 4 extends continuously without interruption. The groove 4 extending in a dotted line means that the groove 4 is partially interrupted at one or more locations, so that the groove 4 extends discontinuously. The part where the groove 4 is partially interrupted is also referred to as the cutout of the groove 4. In the case where the groove 4 extends in a dotted line, the cutout of the groove 4 may be formed at a predetermined interval or at an arbitrary position.

[0090] In order to prevent the expansion of each of the multiple adhesive film pieces 3 along the surface 2a of the peeling film 2, the groove 4 is formed on the surface 2a of the peeling film 2. And the width (line width) of the groove 4 is 15μm or more. The width of the groove 4 is the width of the surface 2a of the peeling film 2, and is the width in the direction orthogonal to the extension direction of the groove 4. In addition, since the groove 4 extends along the outer edge 3a of each of the multiple adhesive film pieces 3, the extension direction of the groove 4 varies depending on the formation position of the groove 4. Therefore, the width of the groove 4 is the width in the direction orthogonal to the extension direction of the groove 4 at the location where the groove 4 is formed. From the viewpoint of being able to prevent the expansion of each of the multiple adhesive film pieces 3 along the surface 2a of the peeling film 2, the width of the groove 4 is preferably 20μm or more. On the other hand, from the viewpoint of being able to easily form the groove 4, the width of the groove 4 is preferably 50μm or less, more preferably 45μm or less, and further preferably 40μm or less. From these viewpoints, the width of the groove 4 is preferably 15 μm or more and 50 μm or less, more preferably 15 μm or more and 45 μm or less, and still more preferably 20 μm or more and 40 μm or less.

[0091] The groove 4 may be located at a position overlapping with the outer edge 3a of each of the plurality of adhesive film sheets 3, or may be located outside the outer edge 3a of each of the plurality of adhesive film sheets 3. In these cases, when the film 1 is viewed from above, the groove 4 has substantially the same shape as each of the plurality of adhesive film sheets 3, that is, has the same shape as or slightly larger than each of the plurality of adhesive film sheets 3. Figure 1 As shown in FIG. 1 , the top view of the film 1 refers to the view from the surface direction of the release film 2 (a direction perpendicular to the surface 2a of the release film 2). Figure 3 to Figure 5 , the case where the groove 4 is located outside the outer edge 3 a of each of the plurality of adhesive films 3 is shown.

[0092] The depth of the groove 4 is not particularly limited, and can be appropriately set within a range that does not penetrate the release film 2. The depth of the groove 4 is the depth in the thickness direction Z of the film 1. For example, from the viewpoint that the groove 4 can be easily formed and the path for each of the plurality of adhesive film sheets 3 to cross the groove 4 can be made longer, the depth of the groove 4 is preferably 10% or more of the thickness of the release film 2, more preferably 20% or more of the thickness of the release film 2, and further preferably 30% or more of the thickness of the release film 2. On the other hand, from the viewpoint that the breakage of the release film 2 can be suppressed, the depth of the groove 4 is preferably 85% or less of the thickness of the release film 2, more preferably 80% or less of the thickness of the release film 2, and further preferably 75% or less of the thickness of the release film 2. From these viewpoints, the depth of the groove 4 is preferably 10% or more and 85% or less of the thickness of the release film 2, more preferably 20% or more and 80% or less of the thickness of the release film 2, and further preferably 30% or more and 75% or less of the thickness of the release film 2.

[0093] From the viewpoint of being able to lengthen the path for each of the plurality of adhesive film sheets 3 to cross the groove 4, the depth of the groove 4 is preferably 20% or more of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, more preferably 30% or more of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, and further preferably 40% or more of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3. On the other hand, from the viewpoint of being able to easily form the groove 4, the depth of the groove 4 is preferably 100% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, more preferably 90% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, and further preferably 80% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3. From these viewpoints, the depth of the groove 4 is preferably 20% or more and 100% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, more preferably 30% or more and 90% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3, and further preferably 40% or more and 80% or less of the thickness of the adhesive film sheet 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3. In addition, the thickness of the adhesive film sheet 3 and the depth of the groove 4 are the same thickness in the thickness direction Z of the film 1. Furthermore, since the groove 4 extends along the outer edge 3a of each of the plurality of adhesive film sheets 3, each of the plurality of adhesive film sheets 3 is surrounded by the groove 4. Therefore, when one adhesive film sheet 3 is used as the target adhesive film sheet and the groove 4 extending along the outer edge 3a of the target adhesive film sheet is used as the target groove, the adhesive film sheets 3 surrounded by the groove 4 among the plurality of adhesive film sheets 3 become the target adhesive film sheets surrounded by the target groove.

[0094] [Method for producing film]

[0095] like Fig.10 As shown, the film manufacturing method includes, for example, an adhesive film layer forming step (S11), an adhesive film layer cutting step (S12) performed after the adhesive film layer forming step (S11), and a blank stripping step (S13) performed after the adhesive film layer cutting step (S12).

[0096] In the adhesive film layer forming step (S11), first, Fig.11 (a) and Fig.12 As shown in (a), a peeling film 2 is prepared. Fig.11 (b) and Fig.12 As shown in (b), an adhesive film layer 3A is formed on the entire surface of the release film 2. The adhesive film layer 3A is a layer that becomes a plurality of adhesive film sheets 3. The adhesive film layer 3A is formed, for example, of an adhesive 6 and conductive particles 7 contained in the adhesive 6. The adhesive 6 and conductive particles 7 that form the adhesive film layer 3A are the same as the adhesive 6 and conductive particles 7 that form the adhesive film sheets 3 described above.

[0097] like Fig.11 (c) and Fig.12 As shown in (c), in the adhesive film layer cutting step (S12), the adhesive film layer 3A formed on the release film 2 is cut along the outer edge line 3B which is the outer edge 3a of the plurality of adhesive film pieces 3 provided on the film 1, and the release film 2 is half-cut. The cutting of the adhesive film layer 3A and the half-cutting of the release film 2 are performed, for example, by pressing the adhesive film layer 3A on a roller cutter having a cutting blade formed on the outer peripheral surface. As the cutting blade, for example, a PINNACLE (registered trademark) blade, a Thomson blade, etc. can be used. Half-cutting the release film 2 means cutting the surface 2a of the release film 2 on the adhesive film layer 3A side in a manner that does not cut the back side 2b of the release film 2 on the opposite side to the adhesive film layer 3A. Thus, a cutting line is formed on the adhesive film layer 3A along the outer edge 3a of each of the plurality of adhesive film sheets 3 provided on the film 1, and a half-cut line is formed on the release film 2 along the outer edge 3a of each of the plurality of adhesive film sheets 3 provided on the film 1. At this time, the release film 2 is half-cut in such a manner that the width of the half-cut line of the release film 2 becomes 15 μm or more. In addition, by appropriately setting the thickness of the cutting blade, the shape of the blade, the cutting depth of the cutting blade relative to the release film 2, etc., the width of the half-cut line of the release film 2 can be set to be 15 μm or more. Thus, the adhesive film layer 3A is separated into an inner portion 3A1 located inside the outer edge line 3B and a plurality of blank portions 3A2 located outside the outer edge line 3B. The inner portion 3A1 is a portion that becomes the plurality of adhesive film sheets 3 provided on the film 1. The blank portion 3A2 is a portion that becomes a portion other than the plurality of adhesive film sheets 3 provided on the film 1.

[0098] like Fig.11 (d) and Fig.12 As shown in (d), in the blank peeling process (S13), the blank part 3A2 of the adhesive film layer 3A is peeled off from the peeling film 2 along the cut outer edge line 3B. For example, the blank part 3A2 is peeled off by adhering a pressure-sensitive adhesive tape to the blank part 3A2, pulling the pressure-sensitive adhesive tape, and peeling the blank part 3A2 from the peeling film 2. Therefore, the inner part 3A1 remaining on the peeling film 2 becomes a plurality of adhesive film pieces 3 provided on the film 1. Thus, the film 1 having a plurality of adhesive film pieces 3 provided on the peeling film 2 is manufactured. And, the half-cut line of the peeling film 2 becomes a groove 4 formed on the surface 2a of the peeling film 2 on the side of the plurality of adhesive film pieces 3 and extending along the outer edge 3a of each of the plurality of adhesive film pieces 3. Therefore, in the film 1 manufactured in this way, the groove 4 is formed on the surface 2a of the release film 2 on the side of the plurality of adhesive film pieces 3 and extends along the outer edge 3a of each of the plurality of adhesive film pieces 3, and the width of the groove 4 is 15 μm or more.

[0099] [Wound body]

[0100] like Figure 2 As shown, the wound body 15 includes a long (strip-shaped) film 1 and a winding core 14 around which the film 1 is wound. That is, the wound body 15 is formed by winding the film 1 around the winding core 14.

[0101] The winding core 14 includes a core material 14a and a pair of side plates 14b. The core material 14a is formed into a cylindrical shape. The film 1 is wound on the outer peripheral surface of the core material 14a. The pair of side plates 14b are installed at both ends in the axial direction of the core material 14a. The pair of side plates 14b support the film 1 from the left and right. The interval between the pair of side plates 14b is slightly wider than the width of the film 1.

[0102] [Connection structure]

[0103] like Fig.13 As shown, the connection structure 16 includes a first member 17 having a first adhesive surface 17a, a second member 18 having a second adhesive surface 18a, and an adhesive film 3 connecting the first adhesive surface 17a and the second adhesive surface 18a.

[0104] The first component 17 is, for example, a chip part such as an IC chip, an LSI chip, a resistor chip, a capacitor chip, a photoelectric conversion part such as an LED, an image sensor, a strain sensor, a pressure sensor, an acoustic part, a piezoelectric conversion part such as a piezoelectric element, a circuit forming part such as a flexible printed circuit board, a thermometer, a heat sink, and a thermal management part. In the first component 17, the surface facing the second component 18 is a first adhesive surface 17a. On the first adhesive surface 17a, for example, a first electrode (not shown) for conducting with the second component 18 is arranged.

[0105] The second member 18 is, for example, a glass substrate, a polyimide substrate, a polyamide-imide substrate, a polyethylene terephthalate substrate, a polycarbonate substrate, a cycloolefin polymer (COP) substrate, a polyethylene naphthalate substrate, a glass-reinforced epoxy resin substrate, a phenolic paper substrate, a ceramic substrate, a laminated board, or a silicon substrate. In the second member 18, the surface of the first member 17 that is opposite to the first adhesive surface 17a becomes the second adhesive surface 18a. On the second adhesive surface 18a, for example, a second electrode (not shown) for conducting with the first member 17 is arranged.

[0106] In addition, there is no clear distinction between the first component 17 and the second component 18, and any component can be applied to each component.

[0107] The adhesive film sheet 3 is an adhesive film sheet 3 peeled from the above-mentioned film 1. The adhesive film sheet 3 connects the first adhesive surface 17a and the second adhesive surface 18a through the adhesive 6. When the adhesive film sheet 3 has anisotropic conductivity by containing the conductive particles 7, the first electrode of the first adhesive surface 17a and the second electrode of the second adhesive surface 18a can be electrically connected through the conductive particles 7.

[0108] [Method for producing a connection structure]

[0109] like Fig.14 As shown, the method for manufacturing a connection structure includes a preparation step (S21) and a connection step (S22) performed after the preparation step (S21).

[0110] In the preparation step (S21), the above-mentioned film 1 is prepared. At this time, a roll 15 in which the film 1 is wound is prepared as the film 1. In the preparation step (S21), the above-mentioned film manufacturing method may be performed, or only the film 1 manufactured by the above-mentioned film manufacturing method may be prepared.

[0111] like Fig.15 As shown, the connection step (S22) includes a position detection step (S31), an attachment step (S32) and an overlapping step (S33).

[0112] In the position detection step (S31), first, the film 1 is unwound from the winding body 15. Fig.16 As shown, the position of the adhesive film sheet 3 in the film 1 is detected by the camera device 33. At this time, the camera device 33 can be arranged on the adhesive film sheet 3 side of the peeling film 2, and can also be arranged on the side of the peeling film 2 opposite to the adhesive film sheet 3. Fig.16 As shown, in this embodiment, the imaging device 33 is disposed on the side of the release film 2 opposite to the adhesive film 3. In this case, by using the light-transmissive release film 2, the imaging device 33 can detect the position of the adhesive film 3 in the film 1 from the release film 2 side.

[0113] In the attaching step (S32), the adhesive film sheet 3 is attached to the first adhesive surface 17a according to the position detected by the position detection step (S31). Thereafter, the release film 2 is peeled off from the adhesive film sheet 3 attached to the first adhesive surface 17a. In this step, the adhesive film sheet 3 can be easily peeled off from the release film 2 by applying heat and pressure within a range that does not affect the curing degree of the adhesive of the adhesive film sheet 3. For example, the heating temperature may be 70°C, the heating time may be 1 second, and the area pressure relative to the adhesive film sheet 3 may be 1 MPa.

[0114] In the overlapping step (S33), the first adhesive surface 17a and the second adhesive surface 18a are overlapped via the adhesive film 3. Thus, the first adhesive surface 17a and the second adhesive surface 18a are temporarily connected by the adhesive 6 of the adhesive film 3. Moreover, by applying pressure to the first component 17 and the second component 18, and applying heat or light to the adhesive 6 of the adhesive film 3, the adhesive 6 is cured. Thus, the connection structure 16 in which the first adhesive surface 17a and the second adhesive surface 18a are connected by the adhesive film 3 is obtained. In the case where the adhesive film 3 has anisotropic conductivity by containing conductive particles 7, before the adhesive 6 is cured, the first component 17 and the second component 18 are pressurized and the first component 17 and the second component 18 are connected by the conductive particles 7 of the adhesive film 3. Thus, the connection structure 16 is manufactured.

[0115] Thus, in the film 1 involved in the present embodiment, since the plurality of adhesive film pieces 3 are provided on the release film 2, each of the plurality of adhesive film pieces 3 tries to spread along the surface 2a of the release film 2. However, the groove 4 is formed on the surface 2a of the release film 2 on the side of the plurality of adhesive film pieces 3 and extends along the outer edge 3a of each of the plurality of adhesive film pieces 3, and the width of the groove 4 is 15 μm or more. Therefore, the groove 4 blocks the expansion of each of the plurality of adhesive film pieces 3 along the surface 2a of the release film 2, and each of the plurality of adhesive film pieces 3 can be suppressed from spreading across the groove 4.

[0116] Furthermore, in the film 1 , since the groove 4 is located outside the outer edge 3 a of each of the plurality of adhesive film pieces 3 , the spreading of each of the plurality of adhesive film pieces 3 can be further suppressed.

[0117] Furthermore, in the film 1, the depth of the groove 4 is 10% or more of the thickness of the release film 2, so that the width of the groove 4 can be easily set to 15 μm or more, and the path for each of the plurality of adhesive film sheets 3 to cross the groove 4 can be lengthened. Thus, each of the plurality of adhesive film sheets 3 can be further prevented from crossing the groove 4 and expanding.

[0118] Furthermore, in the film 1 , the depth of the grooves 4 is 85% or less of the thickness of the release film 2 , so that the breakage of the release film 2 can be suppressed.

[0119] Furthermore, in the film 1, the depth of the groove 4 is 20% or more of the thickness of the adhesive film 3 surrounded by the groove 4, so that the path for each of the plurality of adhesive film sheets 3 to cross the groove 4 can be lengthened. This can further prevent each of the plurality of adhesive film sheets 3 from spreading across the groove 4.

[0120] Furthermore, in the film 1 , the groove 4 can be easily formed by making the depth of the groove 4 equal to or less than 100% of the thickness of the adhesive film sheet 3 surrounded by the groove 4 .

[0121] In the film 1, the adhesive 6 forming each of the plurality of adhesive sheets 3 has a multilayer structure, so each of the plurality of adhesive sheets 3 is easily expanded. However, as described above, since the groove 4 has a width of 15 μm or more, each of the plurality of adhesive sheets 3 can be prevented from expanding across the groove 4.

[0122] Furthermore, in the film 1, the degree of curing measured by differential scanning calorimetry of the adhesive 6 forming each of the multiple adhesive film sheets 3 is 80% or more under the condition of 150°C for 10 seconds, 80% or more under the condition of 160°C for 10 seconds, 80% or more under the condition of 170°C for 10 seconds, 80% or more under the condition of 180°C for 10 seconds, 80% or more under the condition of 200°C for 10 seconds, 80% or more under the condition of 210°C for 10 seconds, or 80% or more under the condition of 230°C for 10 seconds, which can reduce the influence of heat on parts other than the connection parts and can appropriately suppress the expansion of each of the multiple adhesive film sheets 3 across the groove 4.

[0123] Furthermore, in the film 1, as the adhesive 6 for forming each of the multiple adhesive film sheets 3, thermoplastic resins such as styrene resin and polyester resin, thermosetting resins such as epoxy resin, acrylic resin, and silicone resin, a mixture of these thermoplastic resins and thermosetting resins, and a photocurable resin are used, thereby appropriately suppressing each of the multiple adhesive film sheets 3 from extending across the groove 4.

[0124] Furthermore, in the film 1, since the plurality of adhesive film sheets 3 are separated from each other, the adhesive film sheet 3 can be attached to the adhesive surface without affecting the adjacent adhesive film sheet 3. Thus, the adhesive film sheet 3 can be easily attached to the adhesive surface.

[0125] In the film 1, the plurality of adhesive film pieces 3 are separated from the edge of the release film 2 in the width direction of the release film 2, so that the adhesive film pieces 3 can be prevented from peeling off from the release film 2 when the end of the release film 2 interferes with other members.

[0126] Furthermore, in the film 1 , since the plurality of adhesive film sheets 3 are arranged in a row along the longitudinal direction X of the release film 2 , the adhesive film sheets 3 can be easily attached.

[0127] Furthermore, in the film 1, since at least one of the plurality of adhesive sheets 3 has the hole 3b, the adhesive sheet 3 can be appropriately attached to a portion having a portion in the center where the adhesive sheet 3 is not to be attached, for example.

[0128] Furthermore, in the film 1, since the plurality of adhesive film sheets 3 have the same shape, the adhesive film sheets 3 can be efficiently attached to the plurality of adhesive surfaces having the same shape.

[0129] Furthermore, in the film 1 , since the adhesive film sheet 3 has conductivity, two members connected via the adhesive film sheet 3 can be electrically connected.

[0130] Furthermore, in the film 1 , since the adhesive film sheet 3 contains the conductive particles 7 , conductivity can be easily imparted to the adhesive film sheet 3 .

[0131] In the winding body 15 involved in the present embodiment, since the above-mentioned film 1 is wound on the core 14, a winding pressure that presses the core material 14a (center) of the core 14 is generated on the film 1. Therefore, the adhesive film sheet 3 clamped by the release film 2 from the inner layer side (core side) and the outer layer side (the side opposite to the core) is pressed from the inner layer side and the outer layer side by the release film 2 to try to deform and unfold along the surface 2a of the release film 2. However, the film 1 has a groove 4 formed on the surface 2a of the plurality of adhesive film sheets 3 of the release film 2 and extending along the outer edge 3a of each of the plurality of adhesive film sheets 3, and the width of the groove 4 is 15μm or more. Therefore, by preventing the expansion of each of the plurality of adhesive film sheets 3 along the surface 2a of the release film 2 by the groove 4, it is possible to suppress the expansion of each of the plurality of adhesive film sheets 3 across the groove 4.

[0132] In the connection structure 16 according to the present embodiment, the first member 17 and the second member 18 are connected by the adhesive film 3 , so that the connection structure 16 in which the adhesive film 3 is prevented from protruding from the first member 17 and the second member 18 can be obtained.

[0133] In the method for manufacturing a connection structure according to the present embodiment, the first adhesive surface 17a of the first component 17 and the second adhesive surface 18a of the second component 18 are connected via the adhesive film sheet 3 of the above-mentioned film 1, so that the connection structure 16 in which the adhesive film sheet 3 is suppressed from protruding from the first component 17 and the second component 18 can be manufactured.

[0134] The present invention is not limited to the above-described embodiment, and appropriate changes can be made without departing from the gist of the present invention.

[0135] For example, in the above embodiment, an example of the connecting step in the method for manufacturing a connected structure is described, but the connecting step may be implemented by any method as long as a film can be used and the first member and the second member can be connected through the adhesive sheet of the film.

[0136] Furthermore, for example, in the above embodiment, the film has been described as having a two-layer structure in which a plurality of adhesive film sheets are provided on a release film, but a three-layer structure in which a second release film is provided on a plurality of adhesive film sheets may also be used.

[0137] All or part of the above examples can be represented by [1] to

[18] described below, but are not limited to the following descriptions. [1]

[0139] A film comprising: a long strip of release film; a plurality of adhesive film sheets arranged on the release film; and a groove formed on the surface of the release film on the side of the plurality of adhesive film sheets and extending along the outer edge of each of the plurality of adhesive film sheets, wherein the width of the groove is greater than 15 μm. [2]

[0141] The film according to [1], wherein the groove is located outside the outer edge of each of the plurality of adhesive film sheets. [3]

[0143] The film according to [1] or [2], wherein the depth of the groove is 10% or more of the thickness of the release film. [4]

[0145] The film according to any one of [1] to [3], wherein the depth of the groove is 85% or less of the thickness of the release film. [5]

[0147] The film according to any one of [1] to [4], wherein the depth of the groove is 20% or more of the thickness of the adhesive film sheet surrounded by the groove among the plurality of adhesive film sheets. [6]

[0149] The film according to any one of [1] to [5], wherein the depth of the groove is 100% or less of the thickness of the adhesive film sheet surrounded by the groove among the plurality of adhesive film sheets. [7]

[0151] The film according to any one of [1] to [6], wherein the adhesive forming each of the plurality of adhesive film sheets has a multilayer structure. [8]

[0153] The film according to any one of [1] to [7], wherein the degree of cure of the adhesive forming each of the plurality of adhesive film sheets measured by differential scanning calorimetry at 150° C. for 10 seconds is 80% or more. [9]

[0155] The film according to any one of [1] to [8], wherein the plurality of adhesive film pieces are separated from each other.

[10]

[0157] The film according to any one of [1] to [9], wherein the plurality of adhesive film pieces are separated from an end edge of the release film in a width direction of the release film.

[11]

[0159] The film according to any one of [1] to

[10] , wherein the plurality of adhesive film pieces are arranged in a row along the long side direction of the release film.

[12]

[0161] The film according to any one of [1] to

[11] , wherein at least one of the plurality of adhesive film sheets has a hole.

[13]

[0163] The film according to any one of [1] to

[12] , wherein the plurality of adhesive film pieces have the same shape.

[14]

[0165] The film according to any one of [1] to

[13] , wherein the adhesive film sheet has conductivity.

[15]

[0167] The film according to

[14] , wherein the adhesive film sheet contains conductive particles.

[16]

[0169] A wound body comprising: the film according to any one of [1] to

[15] ; and a winding core around which the film is wound.

[17]

[0171] A connection structure comprising: a first component having a first adhesive surface; a second component having a second adhesive surface; and the adhesive film described in any one of [1] to

[15] for connecting the first adhesive surface and the second adhesive surface.

[18]

[0173] A method for manufacturing a connection structure, comprising: a preparation step of preparing the film described in any one of [1] to

[15] ; and a connection step of connecting a first adhesive surface of a first component and a second adhesive surface of a second component via the adhesive film sheet of the film.

[0174] Example

[0175] Next, examples of the present invention will be described. However, the present invention is not limited to the following examples.

[0176] (Example 1)

[0177] An adhesive film layer containing an adhesive and conductive particles is formed on the entire surface of the long strip of release film. Next, the adhesive film layer formed on the release film is cut along the outer edge line that becomes the outer edge of the multiple adhesive film sheets arranged on the film by a roller cutter having a PINNACLE blade formed on the outer peripheral surface, and the release film is cut in half. Next, along the cut outer line, the blank portion of the adhesive film layer that becomes the portion other than the multiple adhesive film sheets arranged on the film is peeled off from the release film. Thus, multiple adhesive film sheets are arranged on the release film, and grooves are formed on the surface of the multiple adhesive film sheets side of the release film and extending along the outer edge of each of the multiple adhesive film sheets, thereby obtaining the film of Example 1. Then, a winding body in which the film of Example 1 is wound on a winding core with a tension of 1.5N is prepared, the film is unwound from the winding body, the film is cut at an arbitrary position, the cut surface is used as an observation surface, and photographed with a scanning electron microscope. The scanning electron microscope used is S8020 manufactured by Hitachi High-Tech Corporation. A schematic diagram of the captured image is shown in Fig.17 .

[0178] like Fig.17 As shown, in the observation surface, the width of the groove is 25.8μm, the depth of the groove is 28.6μm, the thickness of the peeling film is 53.6μm, the ratio of the depth of the groove to the thickness of the peeling film is 53%, and the thickness of the adhesive film sheet is 20.4μm. In addition, the states of the adhesive film sheet and the peeling film in the film of Example 1 were observed. When observing the state of the adhesive film sheet, the case where the adhesive film sheet does not extend across the groove is set as A, and the case where the adhesive film sheet extends across the groove is set as B. In the observation of the state of the peeling film, the case where the peeling film is not broken is set as A, and the case where the peeling film is broken is set as B. The results are shown in Fig. 22 .

[0179] (Example 2)

[0180] The film of Example 2 was obtained in the same manner as in Example 1. In addition, a roll was prepared by winding the film of Example 2 around a winding core in the same manner as in Example 1, unwinding the film from the roll, cutting the film at an arbitrary position, and photographing the cut surface as an observation surface using a scanning electron microscope. A schematic diagram of the photographed image is shown in Fig.18 .

[0181] like Fig.18As shown in the observation surface, the width of the groove is 30.5 μm, the depth of the groove is 40.8 μm, the thickness of the peeling film is 52.4 μm, the ratio of the depth of the groove to the thickness of the peeling film is 78%, and the thickness of the adhesive film sheet is 21.3 μm. Then, the state of the adhesive film sheet and the peeling film in the film of Example 2 was observed in the same manner as in Example 1. The results are shown in Fig. 22 .

[0182] (Example 3)

[0183] The film of Example 3 was obtained in the same manner as in Example 1. In addition, a roll was prepared by winding the film of Example 3 around a winding core in the same manner as in Example 1, unwinding the film from the roll, cutting the film at an arbitrary position, and photographing the cut surface as an observation surface using a scanning electron microscope. A schematic diagram of the photographed image is shown in Fig.19 .

[0184] like Fig.19 As shown in the observation surface, the width of the groove is 34.6 μm, the depth of the groove is 51.6 μm, the thickness of the peeling film is 62.9 μm, the ratio of the groove depth to the thickness of the peeling film is 82%, and the thickness of the adhesive film sheet is 28.3 μm. Then, the state of the adhesive film sheet and the peeling film in the film of Example 3 was observed in the same manner as in Example 1. The results are shown in Fig. 22 .

[0185] (Example 4)

[0186] The film of Example 4 was obtained in the same manner as in Example 1. In addition, a roll was prepared by winding the film of Example 4 around a winding core in the same manner as in Example 1, unwinding the film from the roll, cutting the film at an arbitrary position, and photographing the cut surface as an observation surface using a scanning electron microscope. A schematic diagram of the photographed image is shown in Fig. 20 .

[0187] like Fig. 20 As shown in the observation surface, the width of the groove is 35.0 μm, the depth of the groove is 52.4 μm, the thickness of the peeling film is 59.5 μm, the ratio of the groove depth to the thickness of the peeling film is 88%, and the thickness of the adhesive film sheet is 29.4 μm. Then, the state of the adhesive film sheet and the peeling film in the film of Example 4 was observed in the same manner as in Example 1. The results are shown in Fig. 22 .

[0188] (Comparative Example 1)

[0189] The film of Comparative Example 1 was obtained in the same manner as in Example 1. In addition, a roll was prepared by winding the film of Comparative Example 1 around a roll core in the same manner as in Example 1, unwinding the film from the roll, cutting the film at an arbitrary position, and photographing the cut surface as an observation surface using a scanning electron microscope. A schematic diagram of the photographed image is shown in Fig.21 .

[0190] like Fig.21 As shown in FIG. 1 , in the observed surface, the width of the groove is 11.0 μm, the depth of the groove is 4.37 μm, the thickness of the release film is 50.2 μm, the ratio of the groove depth to the thickness of the release film is 9%, and the thickness of the adhesive film sheet is 26.4 μm. Then, the state of the adhesive film sheet in the film of Comparative Example 1 was observed in the same manner as in Example 1. The results are shown in FIG. Fig. 22 .

[0191] (Inspection)

[0192] like Fig. 22 As shown in the figure, in Comparative Example 1 where the groove width is less than 15 μm, the adhesive film piece spreads across the groove, but in Examples 1 to 4 where the groove width is greater than 15 μm, the adhesive film piece does not spread across the groove. Therefore, it is estimated that by setting the groove width to greater than 15 μm, the adhesive film piece can be prevented from spreading across the groove.

[0193] Furthermore, in Example 4 where the ratio of the groove depth to the thickness of the release film was greater than 85%, the release film was broken, but in Examples 1 to 3 where the ratio of the groove depth to the thickness of the release film was 85% or less, the release film was not broken. Therefore, it is estimated that by setting the ratio of the groove depth to the thickness of the release film to 85% or less, the breakage of the release film can be suppressed.

[0194] Industrial Applicability

[0195] The present invention can be utilized as, for example, a film, a wound body, a connected structure, and a method for producing the connected structure.

[0196] Explanation of symbols

[0197] 1-film, 2-peeling film, 2a-surface, 2b-back side, 3-adhesive film sheet, 3a-outer edge, 3A-adhesive film layer, 3A1-inner part, 3A2-blank part, 3b-hole, 3B-outer edge line, 4-groove, 6-adhesive, 7-conductive particles, 8-conductive adhesive area, 9-non-conductive adhesive area, 14-winding core, 14a-core material, 14b-side plate, 15-winding body, 16-connecting structure, 17-first component, 17a-first adhesive surface, 18-second component, 18a-second adhesive surface, 33-camera device, X-long side direction, Y-width direction, Z-thickness direction.

Claims

1. A film comprising: Long strips of release film; A plurality of adhesive films are disposed on the release film; and a groove formed on a surface of the release film on the side of the plurality of adhesive film sheets and extending along an outer edge of each of the plurality of adhesive film sheets, The width of the groove is 15 μm or more.

2. The film according to claim 1, wherein The groove is located outside the outer edge of each of the plurality of adhesive films.

3. The film according to claim 1 or 2, wherein The depth of the groove is 10% or more of the thickness of the release film.

4. The film according to claim 3, wherein The depth of the groove is 85% or less of the thickness of the release film.

5. The film according to claim 1 or 2, wherein The depth of the groove is greater than or equal to 20% of the thickness of the adhesive film sheets surrounded by the groove among the plurality of adhesive film sheets.

6. The film according to claim 5, wherein The depth of the groove is less than or equal to 100% of the thickness of the adhesive film sheets surrounded by the groove among the plurality of adhesive film sheets.

7. The film according to claim 1 or 2, wherein The adhesive forming each of the plurality of adhesive film sheets has a multi-layer structure.

8. The film according to claim 1 or 2, wherein The degree of curing of the adhesive forming each of the plurality of adhesive films is 80% or more as measured by differential scanning calorimetry under conditions of 150° C. for 10 seconds.

9. The film according to claim 1 or 2, wherein The plurality of adhesive films are separated from each other.

10. The film according to claim 1 or 2, wherein The plurality of adhesive film pieces are separated from the end edge of the release film in the width direction of the release film.

11. The film according to claim 1 or 2, wherein The plurality of adhesive film sheets are arranged in a row along the long side direction of the release film.

12. The film according to claim 1 or 2, wherein At least one of the plurality of adhesive films has a hole.

13. The film according to claim 1 or 2, wherein The plurality of adhesive films have the same shape.

14. The film according to claim 1 or 2, wherein The adhesive film is electrically conductive.

15. The film according to claim 14, wherein The adhesive film contains conductive particles.

16. A wound body comprising: The film according to claim 1 or 2; and A winding core on which the film is wound.

17. A connection structure comprising: a first component having a first adhesive surface; a second component having a second adhesive surface; and The adhesive film according to claim 1 or 2 connecting the first adhesive surface and the second adhesive surface.

18. A method for manufacturing a connection structure, comprising: A preparation step of preparing the film according to claim 1 or 2; and The connecting step connects the first adhesive surface of the first member and the second adhesive surface of the second member via the adhesive film sheet of the film.

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