JP6331280B2 - Adhesive laminate and wound body thereof - Google Patents

Description

  The present invention relates to an adhesive laminate and a wound body thereof.

  An anisotropic conductive material tape is known that enables conduction between electrodes and bonding of substrates by heating and pressurizing between electrodes facing each other. Such anisotropic conductive material tape is sometimes rolled up in a reel shape and provided as a reel product. However, as the amount of anisotropic conductive material tape increases, the time until reel replacement is shortened and produced. There could be problems with efficiency. Further, in the anisotropic conductive material tape having a narrow width, there is a case where winding collapse occurs when the reel shape is used.

  Therefore, in order to lengthen the interval of reel replacement time and prevent deterioration of workability due to winding collapse, a two-layer or three-layer structure in which a base film is provided on one or both sides of a film-like adhesive. There has been proposed an anisotropic conductive material tape in which an anisotropic conductive material is wound many times in the longitudinal direction of a core material (Patent Document 1).

JP 2004-59776 A

  Although the production efficiency is surely improved by the above-mentioned devices, there may be some variation in the performance of products joined with anisotropic conductive material. This is an unavoidable phenomenon with the improvement of production efficiency. It was perceived to be.

  Therefore, even if the object of the present invention is to form a wound body by winding it around a core, it is possible to prevent the collapse of the roll, and it is not necessary to frequently perform replacement during production. It is in providing the adhesive laminated body which also improved performance stability. Another object of the present invention is to provide a wound body of such an adhesive laminate.

  The present invention includes an adhesive layer between a first base film and a second base film facing each other, and the first base film and / or the second base film is provided on the adhesive layer. The present invention provides an adhesive laminate having a pressure-sensitive adhesive layer on the surface opposite to the facing surface.

  A detailed examination of the slight performance variation of the products joined with the adhesive revealed that the components in the adhesive (particularly conductive particles in the case of anisotropic conductive materials) were partially localized. . And after examining the reason why the localization occurs, in the adhesive tape of the two-layer structure, when winding, the back surface of the base film wound on the surface of the adhesive layer comes into contact with the core. In order to wind up while shifting the position, the base film has a shape that covers only a part of the adhesive layer, and the degree of pressing differs between the part covered with the base film and the part not covered with the base film. It was found that migration of components in the material occurred.

  In addition, in the adhesive tape having a three-layer structure, although the adhesive is sandwiched between two base films, since the base film is disposed on the base film when laminated, it is stored or manufactured. It has been found that the adhesive tape moves sideways due to slippage between the base film and the adhesive material is subjected to non-uniform pressure, causing the components of the adhesive material to move. According to the adhesive laminate of the present invention, an adhesive layer is disposed between two base film, and a pressure-sensitive adhesive layer is formed on the surface opposite to the surface facing the adhesive layer of the base film. Therefore, slipping hardly occurs when wound around the core, and the adhesive is difficult to receive uneven pressure or pressure that changes over time, so that localization of components in the adhesive is prevented. . And the performance stability of the product after joining is also improved significantly by this.

  It is preferable that at least one of the main surfaces of the first substrate film and the second substrate film other than the surface having the pressure-sensitive adhesive layer is subjected to a release treatment. By releasing the base film, the peelability between the base film and the adhesive layer or the peelability between the overlapping adhesive laminates can be controlled. It becomes possible to manufacture a rotating body. In addition, when an adhesive layer is provided only in one of the 1st or 2nd base film, it is preferable to perform double-sided mold release processing on the base film not provided with the adhesive layer. Moreover, when an adhesive layer is provided on both the first and second substrate films, it is preferable to perform mold release treatment on both surfaces on the adhesive layer side.

  The first base film and the second base film are preferably base films having a breaking strength of 80 to 400 MPa and a breaking elongation of 30 to 200% (both films having a thickness of 25 μm). Measured at 25 ° C.). By using the base film having such breaking strength and breaking elongation, the adhesive layer is prevented from extending together with the base film. Thereby, the performance stability of the product after joining can be further improved. The breaking strength is more preferably 80 to 300 MPa. In the configuration of the present invention, the above characteristics are exhibited even when the breaking strength is 80 to 115 MPa. The breaking elongation is more preferably 50 to 200%, still more preferably 50 to 150%. In addition, the thickness of the base film is preferably 100 μm or less (preferably 75 μm or less, more preferably 50 μm or less). By making the thickness of the base film within this range, the thickness of the adhesive laminate as a whole can be reduced, and the length that can be wound around the core can be increased, thereby improving productivity. To contribute.

  The thickness of one of the first base film and the second base film can be less than or equal to the other thickness. In the production of the adhesive laminate, it is efficient to form an adhesive layer in this state by forming an adhesive layer on one base film and then covering with the other base film. If the base film to be coated is too thick, the thickness as a whole increases, and the length that can be wound around the core becomes short. Therefore, by making the thickness of one base film equal to or less than the thickness of the other base film (for example, 50% or less), it is possible to prevent the thickness from increasing as a whole. Further, when forming the pressure-sensitive adhesive layer, since there are at least three layers of two base film and adhesive layer, it is difficult to form the pressure-sensitive adhesive layer even if one of the base film is thin. It is not accompanied. Even if one of the base films is equal to or less than the thickness of the other, the presence of the pressure-sensitive adhesive layer prevents the components of the adhesive layer from being unevenly distributed, and the performance stability after joining is exhibited without any problem. On the other hand, even if the structure having two base films does not have an adhesive layer, when the thickness of each base film is different, when the film slips, Uneven pressure is easily applied to the adhesive layer, and the uneven distribution of components increases.

  The width of the adhesive layer is preferably 0.5 to 5 mm. If the width is within this range, not only can it be applied to many applications, but it is difficult to cause twisting or bending when the adhesive laminate is wound around the core, and the performance stability after joining is further enhanced. The above adhesive layer may be an anisotropic conductive material layer.

  The present invention provides a wound body in which the above-described adhesive laminate is wound so that the winding position is shifted in the above direction of the core extending in one direction. The wound body is prevented from being collapsed, and it is not necessary to frequently perform replacement during production, and the performance stability of the product after joining can be improved.

  In the wound body, the pressure-sensitive adhesive layer is preferably disposed on the core side. As a result, the adhesive laminate is firmly fixed to the core, and it is possible to prevent the adhesive laminate from being idle or slipping around the core.

  According to the present invention, even when the wound body is wound around a winding core, the collapse is prevented, and it is not necessary to frequently perform replacement during production. An adhesive laminate with improved stability and a wound body of the adhesive laminate are provided.

(A) is sectional drawing of the anisotropic electrically conductive material laminated body which concerns on 1st Embodiment, (b) is sectional drawing of the anisotropic electrically conductive material laminated body which concerns on 2nd Embodiment. (A) is a side view of the wound body which concerns on 1st Embodiment, (b) is a side view of the wound body which concerns on 2nd Embodiment. (A) is a side view of the wound body which concerns on 3rd Embodiment, (b) is a side view of the wound body which concerns on 4th Embodiment. It is a side view which shows a mode that the anisotropic conductive material laminated body is wound around the winding core.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a cross-sectional view of the anisotropic conductive material laminate according to the embodiment. An anisotropic conductive material laminate 100 according to the first embodiment shown in FIG. 1 (a) includes an anisotropic conductive material layer 6 between a first base film 2 and a second base film 4. The second base film 4 has an adhesive layer 8 on the surface opposite to the surface facing the anisotropic conductive material layer 6.

  An anisotropic conductive material laminate 101 according to the second embodiment shown in FIG. 1B includes an anisotropic conductive material layer 6 between the first base film 2 and the second base film 4. The 1st base film 2 and the 2nd base film 4 have the adhesive layer 8 in the surface opposite to the surface which opposes the anisotropic electrically-conductive material layer 6. FIG.

  The first base film 2 and the second base film 4 may be base films made of the same or different materials. Examples of materials that can be used for these include polypropylene (PP), expanded polypropylene (OPP), and polyethylene terephthalate (PET). The thickness is as described above, and the width is preferably the same as or larger than the width of the anisotropic conductive material layer 6. Specifically, since the width of the anisotropic conductive material layer 6 is preferably 0.5 to 5 mm, a width equal to or wider than 50%, that is, a width of about 0.5 to 7.5 mm is preferable. The first base film 2 and the second base film 4 may have different widths, but it is preferable that the widths are the same for the winding stability of the wound body. Furthermore, when the width | variety of the 1st base film 2 and the 2nd base film 4 is wider than the anisotropic conductive material layer 6, the anisotropic conductive material layer 6 is the 1st base film 2 and the 2nd It is good to arrange at the center position of the base film 4.

  The breaking strength and breaking elongation of the first substrate film 2 and the second substrate film 4 are preferably within the above-mentioned ranges. In addition, since the raw material may differ from the 1st base film 2 and the 2nd base film 4, the value of these breaking strength and breaking elongation may differ. In addition, breaking strength and breaking elongation are measured by the method according to JIS C2318 or this.

  The surface of the first base film 2 and the second base film 4 may be subjected to a release treatment. Here, the “mold release treatment” refers to a treatment that lowers the adhesion of the material by lowering the surface of the base film. As the mold release treatment, a method of surface treatment with silicone or a fluorine compound is typical. In the anisotropic conductive material laminated body 100, it is preferable that the both surfaces of the 1st base film 2 are release-processed. Since the surface on the anisotropic conductive material layer 6 side is subjected to the mold release treatment, the anisotropic conductive material layer 6 can be easily peeled from the first base film 2 when the anisotropic conductive material layer 6 is bonded to an electronic substrate or the like. When the anisotropic conductive material laminate 100 is wound around the core, the pressure-sensitive adhesive layer 8 contacts the back surface of the first base film 2 (the surface opposite to the facing surface of the anisotropic conductive material layer 6). However, the anisotropic conductive material laminate 100 can be easily unwound from the wound body by the release treatment of the back surface. In the anisotropic conductive material laminate 100, the second base film 4 is not necessarily subjected to a release treatment. However, when the release treatment is performed, only the surface facing the anisotropic conductive material layer 6 is targeted. It is preferable to do.

  In the anisotropic conductive material laminate 101, it is preferable to perform the mold release treatment only on the surfaces of the first base film 2 and the second base film 4 that face the anisotropic conductive material layer 6. Thereby, peeling of the anisotropic conductive material layer 6 becomes easy.

  The anisotropic conductive material layer 6 constituting the anisotropic conductive material laminates 100 and 101 is typically one in which conductive particles for obtaining conduction between electrodes are mixed with a resin. As the resin, a thermoplastic resin, a thermosetting resin, a mixed system of a thermoplastic resin and a thermosetting resin, or a photocurable resin can be used (for example, see JP-A No. 55-104007). The conductive particles may not be included and the resin particles may be used alone (see, for example, JP-A-60-262430).

  Examples of the thermoplastic resin include a styrene resin and a polyester resin. As thermosetting resins, epoxy resins, silicone resins, and acrylic resins are known. Usually, heating and pressurization are required to connect both the thermoplastic resin and the thermosetting resin. The heating and pressurization is for obtaining a close contact with the adherend by allowing the resin to flow in the thermoplastic resin, and for further curing the resin in the case of the thermosetting resin. Further, the photo-curing resin is useful for applications requiring connection at a low temperature.

  There is no restriction | limiting in particular in the thickness of the anisotropic electrically-conductive material layer 6, According to the application to apply, it can determine suitably. The anisotropic conductive material layer 6 can have a thickness of, for example, 1 to 100 μm (preferably 5 to 100 μm, more preferably 10 to 40 μm).

  The pressure-sensitive adhesive layer 8 only needs to exhibit adhesiveness at the temperature at which it is stored and used when the anisotropic conductive material laminate is wound. As the component, many types such as an acrylic adhesive, a silicone adhesive, and a rubber adhesive can be applied. The acrylic pressure-sensitive adhesive may be an emulsion, or may be one that is cured by ultraviolet rays or the like and exhibits adhesiveness. On the other hand, as the rubber-based pressure-sensitive adhesive, a type obtained by adding a tackifier to natural rubber, SBR or the like, a styrene-based thermoplastic elastomer (for example, styrene-butylene-styrene block copolymer, styrene-isoprene-styrene block copolymer) Etc.) may be of the type obtained by adding a tackifier.

  The thickness of the pressure-sensitive adhesive layer 8 is arbitrary, but it is preferably a thin layer in order to prevent flow or glue transfer during long-term storage. As thickness of the adhesive layer 8, it is 1-50 micrometers (preferably 1-30 micrometers, Furthermore, 1-20 micrometers), for example.

  In the anisotropic conductive material laminate 101, the other adhesive layer 8 is positioned on the adhesive layer 8 when wound around the core, so that the degree of crosslinking of the adhesive layer 8 is increased. It is preferable to prevent the pressure-sensitive adhesive layers 8 from being integrated with each other during storage as a wound body. In addition, by making the adhesive forces of the two pressure-sensitive adhesive layers 8 different, it is possible to design such that the anisotropic conductive material laminate 101 can be easily unwound from the wound body.

  FIG. 2 is a side view of the wound body according to the embodiment. A wound body 102 according to the first embodiment shown in FIG. 2 (a) includes the anisotropic conductive material laminate 100 according to the first embodiment, which includes a cylindrical core member 10a and side plates 10b, and extends in one direction. It is wound spirally along the axial direction of the core 10. A wound body 103 according to the second embodiment shown in FIG. 2 (b) spirals the anisotropic conductive material laminate 100 according to the first embodiment along the axial direction of the winding core 10 extending in one direction. Wrapped (does not have side plates).

  The outer diameter of the cylindrical core material 10a can be 60 to 120 mm, preferably 75 to 105 mm. The length of the cylindrical core member 10a in the axial direction can be 50 to 150 mm, preferably 75 to 125 mm.

  The wound bodies 102 and 103 shown in FIGS. 2A and 2B are wound so that the amount of winding of the anisotropic conductive material laminate 100 becomes equal in the axial direction of the core 10. As in the wound bodies 104 and 105 shown in FIGS. 3A and 3B, the amount of winding of the anisotropic conductive material laminate 100 may be different in the axial direction of the core 10. The wound body 104 of the third embodiment shown in FIG. 3A is related to the first embodiment except that the winding amount of the anisotropic conductive material laminate 100 is increased near the center of the core 10. The structure is the same as that of the wound body 102. On the other hand, the wound body 105 of the fourth embodiment shown in FIG. 3B is the same as that of the first embodiment except that the amount of winding of the anisotropic conductive material laminate 100 is increased near both ends of the core 10. It has the same configuration as the wound body 102 according to the above.

  4 is a side view showing a state where the anisotropic conductive material laminate 100 is wound around the core 10 in the wound body 102 according to the first embodiment. As shown in FIG. When the conductive material laminate 100 is spirally wound in one direction and reaches the end of the core 10, it is usually folded and wound in a spiral in the opposite direction.

Examples will be described below, but the present invention is not limited to these examples.
Example 1
(1) Production of laminate of base film and anisotropic conductive material layer 50 g of phenoxy resin (high molecular weight epoxy resin), 20 g of epoxy resin and 5 g of imidazole are added as a film forming material to produce a 30 wt% solution of ethyl acetate. Then, 5% by volume of Ni powder having an average particle diameter of 2.5 μm was added thereto. A base film having a silicone treatment on both sides of a transparent polyethylene terephthalate film (breaking strength: 25 kg / mm ² , breaking elongation: 130%) having a thickness of 50 μm and colored lightly blue was used. The above solution was applied to one side of the base film using a roll coater and dried at 110 ° C. for 5 minutes to obtain a laminate of the base film having a thickness of 50 μm and the anisotropic conductive material layer.

(2) Production of anisotropic conductive material laminate and wound body On the anisotropic conductive material layer of the above laminate, another type of polyethylene terephthalate base film having a thickness of 25 μm (breaking strength 25 kg / mm ² , breaking The pressure-sensitive adhesive layer was applied to the opposite side of the anisotropic conductive material layer side of the base film having a thickness of 25 μm. While this anisotropic conductive film roll was slit into a width of 1.5 mm, an anisotropic conductive material tape was formed, and a wound body was obtained by winding it around a winding core having a diameter of 48 mm and a width of 100 mm with a side plate. . The length of the anisotropic conductive material laminate was 300 m.
Since the anisotropic conductive material laminates are in close contact with each other by the pressure-sensitive adhesive layer, the winding speed is improved and the productivity is improved. Further, deformation of the anisotropic conductive material layer due to the collapse of the anisotropic conductive material laminate was not observed, and the dispersion state of the Ni powder was maintained in a state where there was no practical problem. Moreover, when this wound body was attached to an anisotropic conductive material tape crimping automatic machine and supplied, good results were obtained in the transferability and elongation test of the anisotropic conductive material layer.

(Comparative Example 1)
An anisotropic conductive material laminate having a three-layer structure was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive layer was not formed, and a side plate was attached while slitting to a width of 1.5 mm as in Example 1. A wound body was obtained by laminating many times in the longitudinal direction of a winding core having a diameter of 48 mm and a width of 100 mm and winding the wound core into a wound form. The length of the three-layer anisotropic conductive material laminate was 300 m.
However, since the surfaces of the anisotropic conductive material laminate slide side by side, the roll collapse occurred and the yield decreased. For this reason, the production speed could not be improved. It was also found that the particle density of Ni powder due to deformation of the anisotropic conductive material layer may be localized.

(Comparative Example 2)
A two-layer anisotropic conductive material laminate was prepared in the same manner as in Example 1 and laminated by winding many times in the longitudinal direction of a core with a diameter of 48 mm and a width of 100 mm with a side plate while slitting to a width of 1.5 mm. A wound body was obtained by winding in a winding form. The length of the anisotropic conductive material laminate having a two-layer structure was 300 m. In the anisotropic conductive material laminate having a two-layer structure, deformation (steps) occurred in the anisotropic conductive material layer.
Moreover, it turned out that the particle density of Ni powder by the deformation | transformation of an anisotropic electrically-conductive material layer may localize.

  DESCRIPTION OF SYMBOLS 2 ... 1st base film, 4 ... 2nd base film, 6 ... Anisotropic conductive material layer, 8 ... Adhesive layer, 10a ... Core material, 10b ... Side plate, 10 ... Core, 100, 101 ... Anisotropic conductive material laminate, 102, 103, 104, 105 ... wound body.

Claims (8)

An adhesive layer is provided between the first base film and the second base film facing each other,
The first base film and the second base film, have a pressure-sensitive adhesive layer on the opposite surface to the surface opposite to the adhesive layer,
In the first base film and the second base film, an adhesive laminate in which a release treatment is performed only on a surface facing the adhesive layer . An adhesive layer is provided between the first base film and the second base film facing each other,
The first base film and the second base film, have a pressure-sensitive adhesive layer on the opposite surface to the surface opposite to the adhesive layer,
The adhesive layer is an adhesive laminate , which is an anisotropic conductive material layer . The first base film and the second base film, the opposite surface to the surface opposite to the adhesive layer has an adhesive strength different pressure-sensitive adhesive layer to each other, according to claim 1 or 2 Adhesive laminate.   The first base film and the second base film are base films having a breaking strength of 80 to 400 MPa and a breaking elongation of 30 to 200%. The adhesive material laminate according to Item.   The adhesive laminate according to any one of claims 1 to 4, wherein one thickness of the first base film and the second base film is equal to or less than the other thickness.   The adhesive laminate according to any one of claims 1 to 5, wherein the adhesive layer has a width of 0.5 to 5 mm. The wound laminate wound around the adhesive laminate so that the winding position is shifted in the direction of the core extending in one direction ,
The adhesive laminate includes an adhesive layer between the first base film and the second base film facing each other,
The first base film and the second base film have a pressure-sensitive adhesive layer on a surface opposite to the surface facing the adhesive layer . The wound body according to claim 7, wherein the pressure-sensitive adhesive layer is disposed on the core side.

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