WO2016051829A1 - Electroconductive pressure-sensitive adhesive sheet - Google Patents

Electroconductive pressure-sensitive adhesive sheet Download PDF

Info

Publication number
WO2016051829A1
WO2016051829A1 PCT/JP2015/059735 JP2015059735W WO2016051829A1 WO 2016051829 A1 WO2016051829 A1 WO 2016051829A1 JP 2015059735 W JP2015059735 W JP 2015059735W WO 2016051829 A1 WO2016051829 A1 WO 2016051829A1
Authority
WO
WIPO (PCT)
Prior art keywords
carbon
pressure
sensitive adhesive
based filler
adhesive layer
Prior art date
Application number
PCT/JP2015/059735
Other languages
French (fr)
Japanese (ja)
Inventor
翔 大高
貴洋 植田
大雅 松下
智史 川田
Original Assignee
リンテック株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by リンテック株式会社 filed Critical リンテック株式会社
Priority to JP2016551566A priority Critical patent/JPWO2016051829A1/en
Publication of WO2016051829A1 publication Critical patent/WO2016051829A1/en

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/10—Adhesives in the form of films or foils without carriers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C09J11/02—Non-macromolecular additives
    • C09J11/04—Non-macromolecular additives inorganic
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
    • C09J175/04—Polyurethanes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J201/00—Adhesives based on unspecified macromolecular compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J9/00—Adhesives characterised by their physical nature or the effects produced, e.g. glue sticks
    • C09J9/02—Electrically-conducting adhesives

Definitions

  • the present invention relates to a conductive adhesive sheet.
  • Conductive substances such as copper powder, silver powder, nickel powder, aluminum powder, and other metal powders are used for the pressure-sensitive adhesive composition used in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet. Are widely used in which they are dispersed in an adhesive resin.
  • Patent Document 1 discloses a conductive pressure-sensitive adhesive in which at least one of carbon nanotubes and carbon microcoils, which are conductive materials, is dispersed in an acrylic or rubber-based pressure-sensitive adhesive using a roll kneader or the like, And the electroconductive adhesive sheet using the said electroconductive adhesive is disclosed.
  • a large amount of a conductive material is blended in the pressure-sensitive adhesive composition that is the material for forming the pressure-sensitive adhesive layer, It is necessary to have close contact between the particles.
  • the adhesive strength to the adherend and the adhesiveness to the substrate tend to be lowered.
  • a general conductive material has a higher specific gravity than an adhesive composition, if it is added in a large amount, it will hinder weight reduction of an electronic device.
  • the content of the conductive material is reduced in order to increase the adhesive strength, there is a trade-off problem that the conductivity is lowered.
  • An object of the present invention is to provide a conductive pressure-sensitive adhesive sheet having good adhesive strength and excellent antistatic properties and conductivity.
  • the present inventors pay attention to the dispersion state of the carbon-based filler in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet, and adjust the occupation area ratio of the carbon-based filler on the sticking surface of the pressure-sensitive adhesive layer to a predetermined range.
  • the inventors have found that the above problems can be solved, and have completed the present invention. That is, the present invention provides the following [1] to [11].
  • a conductive adhesive sheet having an adhesive layer containing an adhesive resin (A) and a carbon-based filler (B), The content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.01 to 20% by mass with respect to the total mass of the pressure-sensitive adhesive layer;
  • a conductive pressure-sensitive adhesive sheet wherein when the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan, the occupation area ratio of the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface is 17% or more.
  • the adhesive layer is prepared by stirring using a stirrer
  • the carbon-based filler (B) is dispersed in a string shape,
  • the average thickness of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is 0.5 to 5.0 ⁇ m, and the average aspect ratio is 3.0 or more, [1 ] Or the conductive adhesive sheet according to [2].
  • the carbon-based filler (B) aggregates with respect to the total occupied area occupied by the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface.
  • the adhesive resin (A) according to any one of [1] to [5] above, wherein the adhesive resin (A) includes one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins.
  • Conductive adhesive sheet [7]
  • the content of the carbon filler (B) in the pressure-sensitive adhesive layer is 0.1 to 7% by mass with respect to the total mass of the pressure-sensitive adhesive layer, according to the above [1] to [6]
  • the conductive pressure-sensitive adhesive sheet of the present invention has a good adhesive force and is excellent in antistatic properties and conductivity.
  • 4B is a digital image of Comparative Example 6;
  • an arbitrarily selected region of 10,000 ⁇ m 2 (a square with a side length of 100 ⁇ m) was selected.
  • an arbitrarily selected region of 10,000 ⁇ m 2 (a square with a side length of 100 ⁇ m) is selected.
  • a binarized image obtained by binarizing a digital image obtained by photographing at a magnification of 2000 times (a) is Comparative Example 1, (b) is Comparative Example 2, and (c) is Comparative Example 3.
  • (D) is a comparative example 4, (e) is a comparative example 5, (f) is a comparative example 6, (g) is a comparative example 7, and (h) is a binary image.
  • Mw mass average molecular weight
  • GPC gel permeation chromatography
  • (meth) acrylate is used as a term indicating both “acrylate” and “methacrylate”, and the same applies to other similar terms.
  • unsubstituted in the term “substituted or unsubstituted” means that a hydrogen atom is bonded without being substituted by a substituent.
  • surface resistivity of the conductive adhesive sheet means that the adhesive layer of the conductive adhesive sheet is exposed, unless otherwise specified. The surface resistivity measured from the surface side is meant, and a specific measuring method is as described in the examples.
  • FIG. 1 is a cross-sectional view of the conductive pressure-sensitive adhesive sheet showing an example of the configuration of the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention.
  • the conductive pressure-sensitive adhesive sheet according to one embodiment of the present invention include a conductive pressure-sensitive adhesive sheet 1a having a configuration in which a pressure-sensitive adhesive layer 11 is laminated on a substrate 12 as shown in FIG.
  • the electroconductive adhesive sheet 1b which has the structure which laminated
  • pressure-sensitive adhesive layers 11 and 11 ′ are respectively laminated on both surfaces of a base material as shown in FIG.
  • the electroconductive adhesive sheet 1c which has the structure which the peeling sheets 13 and 13 'laminated
  • the pressure-sensitive adhesive layer 11 and the pressure-sensitive adhesive layer 11 ′ of the conductive pressure-sensitive adhesive sheet 1c may be layers formed from the same type of pressure-sensitive adhesive composition, and are formed from different types of pressure-sensitive adhesive compositions. It may be a layer.
  • the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention may be a substrate-less conductive pressure-sensitive adhesive sheet.
  • a baseless conductive adhesive sheet for example, as shown in FIG. 1 (d), a conductive adhesive sheet 1d having a configuration in which an adhesive layer 11 is sandwiched between two release sheets 13, 13 ′.
  • mode of this invention the electroconductivity which has the structure which wound what provided the adhesive layer on the single side
  • FIG.2 (a) is an example of the perspective view of the adhesive layer which showed typically the mode of dispersion
  • FIG. 2B is an example of a plan view of the pasting surface 11a when the pasting surface 11a of the pressure-sensitive adhesive layer 11 in FIG.
  • the area occupied by the carbon-based filler (B) in an arbitrarily selected region on the sticking surface when the sticking surface of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet is viewed in plan view The rate (hereinafter also referred to as “occupied area ratio of the carbon-based filler (B) on the pasting surface”) is 17% or more.
  • the above-mentioned “when the adhesive surface of the adhesive layer is viewed in plan” means that the adhesive surface 11a of the adhesive layer in FIGS. 1A and 2A is observed from the direction ⁇ . .
  • the occupation area ratio of the carbon-based filler (B) in an arbitrarily selected region on the pasting surface may be 17% or more.
  • there are two sticking surfaces of the adhesive layer to be exposed when the release sheet is removed such as the conductive adhesive sheet 1c in FIG. 1 (c) and the conductive adhesive sheet 1d in FIG. 1 (d).
  • the occupation area rate of the carbon-type filler (B) on each sticking surface should just be 17% or more.
  • the present inventors paid attention to the dispersion state of the carbon-based filler (B) in the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition.
  • the area occupied by the carbon-based filler (B) on the adhesive surface of the pressure-sensitive adhesive layer About the relationship between the rate and the surface resistivity of the conductive adhesive sheet, it was found that there is a certain relationship.
  • the inventors of the present invention increase the occupation area ratio of the carbon-based filler (B) on the pasting surface, and become conductive. It was discovered that the surface resistivity of the pressure-sensitive adhesive sheet was remarkably improved, and the present invention was completed based on the discovery.
  • the dispersion state of the carbon-based filler (B) in the pressure-sensitive adhesive layer is as shown in FIG. It is considered that not only the vicinity of the pasting surface 11a but also the inside of the pressure-sensitive adhesive layer 11 is uniformly dispersed, and a plurality of carbon-based fillers (B) 15 are in contact with each other to form a network network.
  • the carbon-based filler (B) forms a network-like network inside the pressure-sensitive adhesive layer 11, so that the surface resistivity of the conductive pressure-sensitive adhesive sheet can be effectively reduced, and antistatic properties can be obtained. And it is estimated that it can become an electroconductive adhesive sheet excellent in electroconductivity.
  • the carbon-based filler (B) 15 that can be visually recognized from the pasting surface 11a is not necessarily dispersed on the pasting surface 11a or the surface layer portion of the pasting surface 11a, but may be dispersed inside the adhesive layer. included. That is, the carbon-based filler (B) dispersed inside the pressure-sensitive adhesive layer is only in a state that can be visually recognized on the pasting surface 11a when the pasting surface 11a is viewed in plan.
  • FIG. 5A is a photograph of an arbitrarily selected region on the sticking surface at a predetermined magnification when the sticking surface of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet produced in Example 1 is viewed in plan view. It is the acquired digital image. According to the digital image of FIG. 5A, the outline of the carbon-based filler (B) in the vicinity of the application surface of the adhesive layer is dark, but the outline of the carbon-based filler (B) becomes thinner as the distance from the application surface increases. It can be confirmed. In the present application, the digital image is binarized with a predetermined threshold value, and the occupied area of the carbon-based filler (B) in the region is specified (see FIGS. 6 and 7). It is considered that the ratio of occupied portions (occupied area ratio) of the carbon-based filler (B) affects the surface resistivity and adhesive strength of the conductive adhesive sheet.
  • the area occupied by the carbon-based filler (B) in an arbitrarily selected region on the pasting surface is 17% or more, preferably 20 to 99.999%, more preferably It is 25 to 98%, more preferably 35 to 90%, still more preferably 45 to 85%, still more preferably 50 to 80%, and still more preferably 55 to 75%. If the occupied area ratio is less than 17%, it is difficult to reduce the surface resistivity of the conductive adhesive sheet, which is not preferable. On the other hand, the adhesive force of a conductive adhesive sheet can be maintained moderately by the said occupied area rate being 99.999% or less.
  • the value of the occupation area rate of the carbon-type filler (B) on the sticking surface means the value measured by the method as described in an Example. An example of a method for adjusting the value of the occupied area ratio is as described later.
  • the carbon-based filler (B) is preferably dispersed in a string shape in the pressure-sensitive adhesive layer.
  • a carbon-based filler dispersed in a string (hereinafter, also referred to as a “string-like carbon-based filler”) is a long like carbon-based filler (B) 15 shown in FIG.
  • the “cross section” is a cross section obtained by cutting perpendicularly to a tangential direction at an arbitrary point of the carbon-based filler dispersed in a string (for example, a radial cross section in the case of a cylinder).
  • a string for example, a radial cross section in the case of a cylinder.
  • the type, shape, and content of a carbon-based filler blended as a raw material in the preparation of the pressure-sensitive adhesive composition
  • adhesive The pressure-sensitive adhesive layer in which the carbon-based filler (B) is dispersed in a string shape can be formed by appropriately selecting the preparation method (stirring method) of the adhesive composition; a more specific adjustment method will be described later. It is as follows.
  • the average thickness (d) of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is preferably 0.3 to 5.0 ⁇ m, more preferably 0.00.
  • the thickness is 4 to 4.0 ⁇ m, more preferably 0.5 to 3.0 ⁇ m, and still more preferably 0.6 to 2.0 ⁇ m. If the average of thickness (d) is 0.3 micrometer or more, the effect of reducing the surface resistivity of a conductive adhesive sheet can fully be expressed. On the other hand, if the average thickness (d) is 5.0 ⁇ m or less, a plurality of carbon-based fillers (B) dispersed in a string form can easily come into contact with each other, and a network network can be easily formed. As a result, the surface resistivity of the conductive adhesive sheet can be effectively reduced.
  • the thickness (d) of the carbon-based filler (B) dispersed in a string is perpendicular to the tangential direction at an arbitrary point of the string-like carbon-based filler (B).
  • the side of the polygon This means the length of the longest side, specifically the length d in FIG.
  • the value of the above "average of the thickness (d) of a string-like carbon-type filler (B)” means the value measured by the method as described in an Example.
  • the carbon-based fillers (B) blended as raw materials come into contact with each other and aggregate to form a thick carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer.
  • This is considered to be within the above range. Therefore, the average value of the thickness (d) of the carbon-based filler (B) dispersed in a string is usually the average of the short diameter (L) of the carbon-based filler that is a raw material used for preparing the adhesive composition. The value is larger than the value.
  • the average aspect ratio of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is preferably 3.0 or more, more preferably 5.0 or more, and even more preferably 7 0.0 or more, more preferably 15.0 or more. If the average aspect ratio of the carbon-based fillers (B) dispersed in a string is 3.0 or more, the carbon-based fillers (B) dispersed in a string are easily in contact with each other, and a network network Of the carbon-based filler (B) on the pasting surface increases. As a result, the surface resistivity of the conductive adhesive sheet can be effectively reduced.
  • the upper limit of the average aspect ratio of the string-like carbon-based filler (B) is not particularly limited, but is usually 10,000 or less, preferably 5000 or less.
  • the aspect ratio of the carbon-based filler (B) dispersed in a string means the thickness (d) of the string-shaped carbon-based filler (B) (the length of d in FIG. 3). Is a value calculated by the ratio of the length (x) of the string-like carbon-based filler (B) (the length of x in FIG. 3), that is, “length (x) / thickness (d)”. .
  • the value of the “average aspect ratio of the carbon-based filler (B) dispersed in a string” means a value measured by the method described in Examples.
  • Length (x) of string-like carbon-based filler (B) refers to the distance between the two most distant points in the portion having the thickness (d) of the target carbon-based filler, In the string-like carbon fillers (B) 15, 151, 152 shown in FIGS. 3A, 3B, 3C, the length indicated by x is indicated.
  • the length (x ′) of the string-shaped portion is measured in the same manner as the “length (x) of the string-like carbon-based filler (B)”, and the aspect ratio [(x ′ ) / (D)] is 3.0 or more (preferably 5.0 or more, more preferably 7.0 or more, and still more preferably 15.0 or more), the target carbon-based filler (B) can be judged as a carbon-based filler (B) dispersed in a string shape.
  • the carbon-based filler (B) having such a string-shaped portion also contributes to the formation of a network-like network, and can be a factor that increases the value of the occupied area ratio of the carbon-based filler (B) on the pasting surface.
  • the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet A short diameter formed by agglomeration of the carbon-based filler (B) with respect to the total occupied area (100%) occupied by the carbon-based filler (B) in an arbitrarily selected region on the pasting surface when the pasting surface is viewed in plan.
  • the content of non-string aggregates of 4 ⁇ m or more is preferably 50% or less, more preferably 20% or less, more preferably 10% or less, still more preferably 5% or less, and still more preferably 2% or less.
  • non-string-like aggregate is an aggregate having a short diameter of 4 ⁇ m or more formed by agglomeration of the carbon filler (B), and the above-mentioned string-like carbon as shown in FIG. Meaning the aggregate 21 that exists independently without contacting with the system filler (B), more specifically, the thickness (d) can be measured by the method described in the Examples, The aggregate which does not have a string-shaped part whose above-mentioned aspect ratio is 3.0 or more is pointed out.
  • a non-string-like aggregate such as the aggregate 21 in FIG. 4A does not form a network network by the carbon-based filler (B).
  • non-string aggregate is also considered to be a factor that hinders the formation of a network network of the carbon-based filler (B) dispersed in a string. Therefore, it is preferable to reduce the content of the non-string aggregates as much as possible.
  • the aspect ratio [(x ′) / (d)] of at least one of the four string-shaped portions 15a, 15b, 15c, and 15d in contact with the aggregate 22 is 3.0 or more (preferably Is not less than 5.0, more preferably not less than 7.0, and still more preferably not less than 15.0, the aggregate 22 does not fall under the above-mentioned “non-string-like aggregate”. .
  • the string-shaped portion contributes to the formation of a network network, and the occupied area ratio of the carbon-based filler (B) on the pasting surface This can be said to be a factor that increases the value of.
  • the “thickness of the string-shaped portion (d)” is a length measured by the same method as the above-described “thickness (d) of the carbon-based filler (B) dispersed in a string”.
  • the “string-shaped portion length (x ′)” refers to the distance between the two most distant points in the portion having the measurable string-shaped portion thickness (d). For example, FIG. The string-shaped portion 15a shown in b) indicates the length indicated by x ′.
  • the thickness of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is appropriately adjusted according to the use of the conductive pressure-sensitive adhesive sheet, but is preferably 1 to 1200 ⁇ m, more preferably 2 to 600 ⁇ m, and more preferably It is 3 to 300 ⁇ m, more preferably 5 to 250 ⁇ m, still more preferably 10 to 200 ⁇ m, and still more preferably 15 to 150 ⁇ m.
  • the thickness of the pressure-sensitive adhesive layer is 1 ⁇ m or more, good adhesive force can be expressed regardless of the type of adherend.
  • the thickness of the pressure-sensitive adhesive layer is 1200 ⁇ m or less, the resulting conductive pressure-sensitive adhesive sheet has good conductivity.
  • the said electroconductive adhesive sheet is used as a wound body, the winding shift by the adhesive layer deform
  • the content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.01 to 20% by mass with respect to the total mass (100% by mass) of the pressure-sensitive adhesive layer. It is preferably 0.05 to 10% by mass, more preferably 0.1 to 7% by mass, still more preferably 0.2 to 5% by mass, and still more preferably 0.3 to 3.5% by mass.
  • the content of the carbon-based filler (B) is less than 0.01% by mass, it is difficult to increase the occupied area ratio of the carbon-based filler (B) on the pasting surface, and the surface resistance of the obtained conductive adhesive sheet It becomes difficult to lower the rate.
  • the content of the carbon-based filler (B) exceeds 20% by mass, it is difficult to obtain a conductive adhesive sheet having sufficient adhesive force. Moreover, even if content is made high, the surface resistivity of the electroconductive adhesive sheet obtained does not fall so much.
  • the content of the conductive carbon-based filler (B) is usually increased. However, if the content is simply increased, a large amount of the above-mentioned non-string aggregates are formed and hinder the formation of a network network of the carbon-based filler (B). It becomes difficult to lower the surface resistivity as a result.
  • the content of the adhesive resin (A) in the adhesive layer is preferably from 30 to the total mass (100% by mass) of the adhesive layer. It is 99.9% by mass, more preferably 35 to 99% by mass, still more preferably 40 to 98% by mass, and still more preferably 45 to 97% by mass.
  • the content of the adhesive resin (A) or the carbon-based filler (B) with respect to the total mass of the adhesive layer is “effective in the adhesive composition that is a material for forming the adhesive layer. It can also be regarded as “the blending amount of the adhesive resin (A) or the carbon-based filler (B) relative to the total amount (100% by mass) of the component (solid content)”.
  • active ingredient in the adhesive composition means an ingredient excluding a solvent such as water or an organic solvent contained in the adhesive composition.
  • the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has is formed from the adhesive composition containing adhesive resin (A) and a carbonaceous filler (b).
  • a "carbon-type filler (b)" points out the carbon-type filler currently disperse
  • the said adhesive composition may contain general purpose additives, such as a tackifier, a crosslinking agent, a catalyst, a crosslinking accelerator, according to the kind of adhesive resin (A).
  • each component contained in the said adhesive composition which is a forming material of an adhesive layer is demonstrated.
  • the adhesive resin (A) means a resin having adhesiveness by itself and having a mass average molecular weight (Mw) of 10,000 or more.
  • the mass average molecular weight (Mw) of the pressure-sensitive adhesive resin (A) is preferably from the viewpoint of forming a pressure-sensitive adhesive composition that easily forms a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface. It is 10,000 to 2,000,000, more preferably 20,000 to 1,500,000, still more preferably 30,000 to 1,000,000.
  • the content of the adhesive resin (A) in the adhesive composition is preferably 30 to 99.9% by mass with respect to the total amount (100% by mass) of the active ingredient (solid content) in the adhesive composition. More preferably, it is 35 to 99% by mass, still more preferably 40 to 98% by mass, and still more preferably 45 to 97% by mass.
  • the adhesive resin (A) used in one embodiment of the present invention may be an adhesive resin that can form an adhesive composition that easily forms an adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface.
  • an adhesive resin that can form an adhesive composition that easily forms an adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface.
  • acrylic resins urethane resins, polyisobutylene resins, polyester resins, and polyolefin resins. These adhesive resins may be used alone or in combination of two or more.
  • a pressure-sensitive adhesive composition (A) used in one embodiment of the present invention from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface.
  • Preferably contains at least one adhesive resin selected from acrylic resins and urethane resins, and more preferably contains at least one adhesive resin selected from acrylic resins and silyl group-containing urethane resins.
  • it contains a silyl group-containing urethane resin.
  • an acrylic resin used in one embodiment of the present invention for example, a polymer including a structural unit derived from an alkyl (meth) acrylate having a linear or branched alkyl group, or derived from a (meth) acrylate having a cyclic structure And a polymer containing the structural unit.
  • the form of copolymerization is not particularly limited, and examples of the acrylic copolymer include block copolymers, random copolymers, and graft copolymers. Either may be sufficient.
  • the weight average molecular weight (Mw) of the acrylic resin is preferably 100,000 to from the viewpoint of easily forming an adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface. It is 1.5 million, more preferably 200,000 to 1.3 million, still more preferably 350,000 to 1.1 million, and still more preferably 500,000 to 900,000.
  • the acrylic resin used in one embodiment of the present invention includes an alkyl (meth) acrylate (a1 ′) having an alkyl group having 1 to 20 carbon atoms (hereinafter also referred to as “monomer (a1 ′)”).
  • An acrylic copolymer containing the structural unit (a2) derived from the structural unit (a1) derived from and the functional group-containing monomer (a2 ′) (hereinafter also referred to as “monomer (a2 ′)”) is preferable.
  • the said acrylic copolymer may contain the structural unit (a3) derived from other monomers (a3 ') other than a monomer (a1') (a2 ').
  • the number of carbon atoms of the alkyl group contained in the monomer (a1 ′) is preferably 1 to 12, more preferably 4 to 8, and further preferably 4 to 6, from the viewpoint of improving the adhesive property.
  • Examples of the monomer (a1 ′) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tridecyl ( Examples include meth) acrylate and stearyl (meth) acrylate.
  • butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate are preferable, and butyl (meth) acrylate is more preferable.
  • the content of the structural unit (a1) is preferably 50 to 99.5% by mass, more preferably 60 to 99% by mass, and still more preferably based on all the structural units (100% by mass) of the acrylic copolymer. Is 70 to 97% by mass, more preferably 80 to 95% by mass.
  • Examples of the monomer (a2 ′) include a hydroxy group-containing monomer, a carboxy group-containing monomer, an epoxy group-containing monomer, an amino group-containing monomer, a cyano group-containing monomer, a keto group-containing monomer, and an alkoxysilyl group-containing monomer. .
  • a carboxy group-containing monomer is preferable.
  • Examples of the carboxy group-containing monomer include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, and (meth) acrylic acid is preferred.
  • the content of the structural unit (a2) is preferably 0.5 to 50% by weight, more preferably 1 to 40% by weight, and still more preferably based on all the structural units (100% by weight) of the acrylic copolymer. Is 5 to 30% by mass, more preferably 7 to 20% by mass.
  • Examples of the monomer (a3 ′) include cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and dicyclopentenyloxyethyl.
  • Examples include (meth) acrylates having a cyclic structure such as (meth) acrylates and imide (meth) acrylates, vinyl acetate, acrylonitrile, and styrene.
  • the content of the structural unit (a3) is preferably 0 to 30% by weight, more preferably 0 to 20% by weight, and still more preferably 0 to 0% with respect to all the structural units (100% by weight) of the acrylic copolymer.
  • the amount is 10% by mass, more preferably 0 to 5% by mass.
  • the monomers (a1 ′) to (a3 ′) described above may be used alone or in combination of two or more.
  • the urethane resin used in one embodiment of the present invention is not particularly limited as long as it is a polymer having at least one of a urethane bond and a urea bond in at least one of a main chain and a side chain.
  • a chain extender is further added to the urethane-based prepolymer (U1) obtained by reacting a polyol and a polyvalent isocyanate compound, or the urethane-based prepolymer (U1).
  • Examples thereof include a urethane polymer (U2) obtained by performing the chain extension reaction used.
  • the mass average molecular weight (Mw) of the urethane-based resin is preferably 10,000 to 10,000 from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface. It is 200,000, more preferably 12,000 to 150,000, still more preferably 15,000 to 100,000, and still more preferably 20,000 to 70,000.
  • Examples of the polyol used as a raw material for the urethane-based prepolymer (U1) include polyol compounds such as alkylene diol, polyether-type polyol, polyester-type polyol, and polycarbonate-type polyol. It may be a bifunctional diol or a trifunctional triol. Among these polyols, diols are preferable from the viewpoints of availability, reactivity, and the like.
  • diol examples include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, and ethylene.
  • alkylene glycols such as glycol, propylene glycol, diethylene glycol and dipropylene glycol, polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polybutylene glycol, and polyoxyalkylene glycols such as polytetramethylene glycol.
  • a glycol having a mass average molecular weight of 1000 to 3000 is preferable from the viewpoint of suppressing gelation in the reaction.
  • Examples of the polyvalent isocyanate compound used as a raw material for the urethane prepolymer (U1) include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.
  • Examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2 , 6-Tolylene diisocyanate (2,6-TDI), 4,4′-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4 ′ -Diphenyl ether diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, 1,4-tetramethylxyly
  • aliphatic polyisocyanate examples include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HMDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, and dodeca.
  • HMDI hexamethylene diisocyanate
  • pentamethylene diisocyanate 1,2-propylene diisocyanate
  • 2,3-butylene diisocyanate 1,3-butylene diisocyanate
  • dodeca examples include methylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate.
  • Examples of the alicyclic polyisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, Methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, 1,4-bis (isocyanatemethyl) cyclohexane Etc.
  • IPDI 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate
  • 1,3-cyclopentane diisocyanate 1,3-cyclohexane diisocyanate
  • these polyisocyanate compounds may be a trimethylolpropane adduct modified product of the above polyisocyanate, a burette modified product reacted with water, or an isocyanurate modified product containing an isocyanurate ring.
  • polyvalent isocyanate compounds 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2, from the viewpoint of obtaining a urethane polymer having excellent adhesive properties.
  • MDI 4,4′-diphenylmethane diisocyanate
  • 2,4-TDI 2,4-tolylene diisocyanate
  • One or more selected from 6-tolylene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI) and modified products thereof are preferable. From the viewpoint of weather resistance, at least one selected from HMDI, IPDI, and modified products thereof is more preferable.
  • the isocyanate group content (NCO%) in the urethane-based prepolymer (U1) is preferably 0.5 to 12% by mass, more preferably 1 to 4% by mass, as measured according to JIS K 1603. is there.
  • chain extender a compound having at least one of hydroxyl group and amino group, or a compound having at least three of hydroxyl group and amino group is preferable.
  • the compound having at least one of a hydroxyl group and an amino group is preferably at least one compound selected from the group consisting of aliphatic diols, aliphatic diamines, alkanolamines, bisphenols, and aromatic diamines.
  • aliphatic diol examples include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and 1,7-heptanediol.
  • alkylene glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol.
  • Examples of the aliphatic diamine include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, and the like.
  • Examples of the alkanolamine include monoethanolamine, monopropanolamine, isopropanolamine and the like.
  • Examples of bisphenol include bisphenol A and the like.
  • Examples of the aromatic diamine include diphenylmethanediamine, tolylenediamine, xylylenediamine, and the like.
  • Examples of the compound having at least three hydroxyl groups and amino groups include polyols such as trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, 1-amino-2,3-propanediol, and 1-methyl.
  • Examples include amino alcohols such as amino-2,3-propanediol and N- (2-hydroxypropylethanolamine), and ethylene oxide or propylene oxide adducts of tetramethylxylylenediamine.
  • silyl A group-containing urethane resin is preferred.
  • the silyl group-containing urethane resin is preferably a polymer having a hydrolyzable silyl group represented by the following general formula (1) at least one of the main chain and side chain of the above urethane resin. More preferably, the polymer has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain of the urethane resin.
  • X 1 and X 2 each independently represent a hydroxy group or a substituted or unsubstituted alkoxy group, and R 1 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.
  • R 1 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.
  • X 1 and X 2 in the general formula (1) are alkoxy groups, the number of carbon atoms of the alkoxy group is preferably 1 to 12, more preferably 1 to 1, from the viewpoint of hydrolytic dehydration condensation reactivity. 6, more preferably 1 to 3, and still more preferably 1 to 2.
  • the number of carbon atoms of the alkyl group represented by R 1 is preferably 1 to 12, more preferably 1 to 6, and still more preferably 1 to 1, from the viewpoint of the hydrolytic dehydration condensation reactivity. 3, more preferably 1 to 2.
  • substituents when X 1 , X 2 , and R 1 have a substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), a hydroxyl group, a cyano group, a nitro group, and an amino group. Is mentioned.
  • terminal part of the main chain or side chain of the silyl group-containing urethane resin used in one embodiment of the present invention is represented by the following general formulas (2) to (8) (terminal parts -A to G). It is preferable that it has a structure represented by the following general formula (2).
  • X 1 , X 2 and R 1 are the same as those in the general formula (1).
  • R 2 and R 3 each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and the alkyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, Preferably it is 1-6, and more preferably 1-3.
  • A represents an alkylene group, and the alkylene group preferably has 1 to 20, more preferably 1 to 12, and still more preferably 1 to 6.
  • B represents an organic group having 1 to 20 carbon atoms.
  • Examples of the organic group include a substituted or substituted alkyl group having 1 to 20 carbon atoms, a substituted or substituted alkyl group having 1 to 20 carbon atoms, and a substituted or substituted aryl group having 6 to 20 carbon atoms.
  • substituted or substituted alkoxy group having 1 to 20 carbon atoms substituted or substituted aryloxy group having 6 to 20 carbon atoms, substituted or substituted aromatic hydrocarbon group having 6 to 20 carbon atoms, substituted or substituted Substituent heterocyclic group having 2 to 20 carbon atoms, substituted or substituted alkenyl group having 2 to 20 carbon atoms, substituted or substituted alkynyl group having 2 to 20 carbon atoms, substituted or substituted carbon atom having 3 to 3 carbon atoms 20 cycloalkyl groups and the like.
  • R 2 , R 3 , A, and B in the general formulas (2) to (8) have a substituent
  • substituents include a halogen atom (a fluorine atom, a chlorine atom, Bromine atom, iodine atom), cyano group, nitro group and the like.
  • the skeleton of the main chain and side chain of the silyl group-containing urethane resin is the same as that of the above-mentioned urethane resin, but gives an appropriate flexibility to the obtained adhesive composition, and is formed From the viewpoint of facilitating uniform dispersion of the carbon-based filler (B) in the agent layer, a silyl group-containing urethane polymer having a polyoxyalkylene skeleton as the main chain is preferable.
  • the polyoxyalkylene polyoxypropylene and polyoxyethylene are preferable from the above viewpoint, and polyoxypropylene is more preferable.
  • the suitable range of the mass average molecular weight (Mw) of silyl group containing urethane type resin is the same as the suitable range of the above-mentioned mass average molecular weight (Mw) of urethane type resin.
  • the polyisobutylene resin (hereinafter also referred to as “PIB resin”) used in one embodiment of the present invention is not particularly limited as long as it has a polyisobutylene skeleton in at least one of the main chain and the side chain.
  • the mass average molecular weight (Mw) of the PIB-based resin is preferably 20,000 or more from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface. More preferably, it is 30,000 to 1,000,000, more preferably 50,000 to 800,000, and still more preferably 70,000 to 600,000.
  • PIB resin examples include polyisobutylene which is a homopolymer of isobutylene, a copolymer of isobutylene and isoprene, a copolymer of isobutylene and n-butene, a copolymer of isobutylene and butadiene, and these copolymers.
  • examples thereof include halogenated butyl rubber that has been brominated or chlorinated.
  • the structural unit which consists of isobutylene shall be contained most in all the structural units.
  • the content of the structural unit composed of isobutylene is preferably 80 to 100% by weight, more preferably 90 to 100% by weight, and still more preferably 95 to 100% by weight with respect to all the structural units (100% by weight) of the PIB resin. %.
  • These PIB resins may be used alone or in combination of two or more.
  • PIB resin When using a PIB resin, it is preferable to use a PIB resin having a high mass average molecular weight in combination with a PIB resin having a low mass average molecular weight. More specifically, the mass average molecular weight is 270,000 to 600,000.
  • PIB resin (p1) hereinafter also referred to as “PIB resin (p1)”
  • PIB resin (p2) PIB resin having a mass average molecular weight of 50,000 to 250,000
  • the PIB resin (p1) having a high mass average molecular weight it is possible to improve the durability and weather resistance of the pressure-sensitive adhesive layer formed from the obtained pressure-sensitive adhesive composition, and also improve the pressure-sensitive adhesive force. Further, by using the PIB resin (p2) having a low mass average molecular weight, it can be well compatible with the PIB resin (p1), and the PIB resin (p1) can be appropriately plasticized. The wettability of the layer to the adherend can be increased, and the adhesive properties, flexibility, and the like can be improved.
  • the mass average molecular weight (Mw) of the PIB resin (p1) is preferably 270,000 to 600,000, more preferably 290,000 to 480,000, still more preferably 310,000 to 450,000, and even more preferably 320,000 to 400,000. It is.
  • the mass average molecular weight (Mw) of the PIB resin (p2) is preferably 50,000 to 250,000, more preferably 80,000 to 230,000, still more preferably 140,000 to 220,000, and still more preferably 180,000 to 210,000. It is.
  • the content ratio of the PIB resin (p2) to 100 parts by mass of the PIB resin (p1) is preferably 5 to 55 parts by mass, more preferably 6 to 40 parts by mass, still more preferably 7 to 30 parts by mass, and even more.
  • the amount is preferably 8 to 20 parts by mass.
  • the polyester resin used in one embodiment of the present invention is a copolymer obtained by a polycondensation reaction of an acid component and a diol component or a polyol component, and includes a modified product of the copolymer.
  • the polycondensation reaction is performed by a general polyesterification reaction such as a direct esterification method or a transesterification method.
  • the form of copolymerization of the polyester resin is not particularly limited, and the polyester resin may be any of a block copolymer, a random copolymer, and a graft copolymer.
  • the said polyester-type resin may use individually or in combination of 2 or more types.
  • the acid component examples include terephthalic acid, isophthalic acid, phthalic anhydride, ⁇ -naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid or esters thereof, pimelic acid, suberic acid, and azelain.
  • examples thereof include aliphatic dicarboxylic acids such as acid, sebacic acid, undecylenic acid, dodecanedicarboxylic acid or esters thereof; and alicyclic dicarboxylic acids such as 1,4-cyclohexahydrophthalic anhydride.
  • diol component or polyol component examples include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, , 6-hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, etc.
  • Alicyclic glycols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic glycols such as bisphenol A.
  • the polyolefin resin used in one embodiment of the present invention is not particularly limited as long as it is a polymer having a structural unit derived from an olefin compound such as ethylene or propylene.
  • the polyolefin resin is a copolymer
  • the form of copolymerization is not particularly limited, and the polyolefin resin may be any of a block copolymer, a random copolymer, and a graft copolymer. May be.
  • the polyolefin resin may be used alone or in combination of two or more.
  • polyolefin resins include, for example, polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene, polypropylene, copolymers of ethylene and propylene, ethylene and other ⁇ - Copolymers of olefins, copolymers of propylene and other ⁇ -olefins, copolymers of ethylene, propylene and other ⁇ -olefins, copolymers of ethylene and other ethylenically unsaturated monomers Examples thereof include ethylene (vinyl-vinyl acetate copolymer, ethylene-alkyl (meth) acrylate copolymer, etc.) and the like.
  • Examples of the ⁇ -olefin include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 4-methyl-1-hexene and the like.
  • Examples of the ethylenically unsaturated monomer include vinyl acetate, (meth) acrylic acid, alkyl (meth) acrylate, vinyl alcohol, and the like.
  • polypropylene resins containing a structural unit derived from propylene such as polypropylene, a copolymer of ethylene and propylene, and a copolymer of propylene and other ⁇ -olefin are preferable.
  • the carbon-based filler (b) contained in the pressure-sensitive adhesive composition which is a material for forming the pressure-sensitive adhesive layer is a carbon-based filler dispersed in the pressure-sensitive adhesive composition before forming the pressure-sensitive adhesive layer, In the formation process of the layer, the carbon fillers (b) can be aggregated to form the carbon filler (B).
  • the content of the carbon-based filler (b) in the adhesive composition is such that the adhesive resin (A ) Preferably from 100 to 20 parts by weight, preferably from 0.01 to 20 parts by weight, more preferably from 0.05 to 15 parts by weight, more preferably from 0.1 to 10 parts by weight, still more preferably from 0.3 to 7 parts by weight. More preferably, it is 0.5 to 4.5 parts by mass, and still more preferably 0.7 to 3.8 parts by mass.
  • the content of the carbon-based filler (b) with respect to the total amount (100% by mass) of the pressure-sensitive adhesive composition is preferably 0.01 to 20% by mass, more preferably 0.05 to It is 10% by mass, more preferably 0.1-7% by mass, still more preferably 0.2-5% by mass, and still more preferably 0.3-3.5% by mass.
  • the average aspect ratio of the carbon-based filler (b) is a string-like carbon-based filler (in the pressure-sensitive adhesive layer formed so that the occupied area ratio of the carbon-based filler (B) on the pasting surface is increased. From the viewpoint of facilitating dispersion as B), it is preferably 100 to 1200, more preferably 120 to 1000, still more preferably 135 to 500, and still more preferably 140 to 400.
  • the “aspect ratio of the carbon-based filler (b)” is the ratio of the length (H) of the long side to the length (L) of the short side of the target carbon-based filler (b). That is, it is a value calculated from “long side length (H) / short side length (L)”. Further, the “average aspect ratio” is an average value of the “aspect ratio” calculated for 10 carbon fillers (b) as targets. Further, the length (H) of the long side of the carbon-based filler (b) means the length in the height direction (long direction) of the target carbon-based filler (b). In actual measurement, the distance between the two most distant points of the carbon filler (b) as a target may be defined as “long side length (H)”.
  • the short side length (L) of the carbon-based filler (b) is the maximum area of the cut surface when cut perpendicular to the tangential direction at an arbitrary point of the target carbon-based filler.
  • the cross section is a circle or an ellipse, it is a diameter or a long diameter, and if the cross section is a polygon, it means the length of the longest side among the sides of the polygon.
  • the average length (H) of the long side of the carbon-based filler (b) is preferably 0.01 to 2000 ⁇ m, more preferably 0.1 to 1000 ⁇ m, still more preferably 0.3 to 500 ⁇ m, and still more preferably. 0.5 to 100 ⁇ m.
  • the average short side length (L) of the carbon-based filler (b) is preferably 1 to 1000 nm, more preferably 2 to 750 nm, more preferably 3 to 500 nm, still more preferably 5 to 100 nm, and still more preferably. Is 7 to 50 nm.
  • the carbon-based filler (B) can be uniformly dispersed in the pressure-sensitive adhesive layer so that the occupied area ratio of the carbon-based filler (B) on the pasting surface is increased.
  • the shape is not particularly limited as long as it is a simple shape, but a columnar shape, a cylindrical shape, a weight shape, a fiber shape, and a combination thereof are preferable, and a columnar shape, a cylinder shape, a fiber shape, and a combination thereof are more preferable.
  • the carbon-based filler (b) is preferably a carbon-based filler having a shape formed by a fibrous material in which a plurality of single yarns are intertwined, such as wool, and the plurality of single yarns are intertwined.
  • a cylindrical carbon-based filler formed of a fibrous material is more preferable.
  • Examples of the carbon-based filler (b) include conductive fillers containing carbon atoms, and specific examples include carbon nanomaterials, carbon black, milled carbon fiber, and graphite.
  • carbon nanomaterials are preferable from the viewpoints of reducing the surface resistivity of the formed pressure-sensitive adhesive layer and improving the adhesive strength.
  • the carbon nanomaterial is composed of a substance including a graphite sheet having a six-membered ring arrangement as a main structure, but the graphite structure may contain atoms other than carbon atoms such as boron atoms and nitrogen atoms.
  • the carbon nanomaterial may be in a form containing another substance, and the carbon nanomaterial may be in a form modified with another conductive substance.
  • Examples of the carbon nanomaterial include carbon nanotube (CNT), carbon nanofiber, carbon nanohorn, carbon nanocone, fullerene, and the like, and carbon nanotube is preferable.
  • the carbon nanotube is a cylindrical carbon polyhedron having a structure in which a graphite (graphite) sheet mainly having a carbon 6-membered ring structure is closed in a cylindrical shape.
  • the carbon nanotube includes a single-walled carbon nanotube having a structure in which a single-layer graphite sheet is closed in a cylindrical shape, a double-walled carbon nanotube having a structure in which a two-layer graphite sheet is closed in a cylindrical shape, and a three-layered graphite sheet
  • a single-walled carbon nanotube having a structure in which a single-layer graphite sheet is closed in a cylindrical shape a double-walled carbon nanotube having a structure in which a two-layer graphite sheet is closed in a cylindrical shape
  • a three-layered graphite sheet There are multi-walled carbon nanotubes having a multi-layered structure concentrically closed as described above, and any two or more of these can be used in combination.
  • the pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a tackifier.
  • a tackifier when the above-mentioned urethane-based resin and PIB-based resin are used as the adhesive resin (A), it is preferable to contain a tackifier from the viewpoint of improving the adhesive strength of the formed adhesive layer.
  • the mass average molecular weight (Mw) of this tackifier is usually less than 10,000, and is distinguished from the above-mentioned adhesive resin (A).
  • the mass average molecular weight (Mw) of the tackifier is preferably 400 to 4000, more preferably 800 to 1500, from the viewpoint of improving the adhesive strength of the formed pressure-sensitive adhesive layer.
  • the softening point of the tackifier is preferably 110 ° C. or higher, more preferably 110 to 180 ° C., still more preferably 115 to 175 ° C., and still more preferably 120 to 170 ° C.
  • the “softening point” of the tackifier means a value measured according to JIS K2531.
  • the tackifier examples include rosin resins such as rosin resins, rosin phenol resins, and ester compounds thereof; hydrogenated rosin resins obtained by hydrogenating these rosin resins; terpene resins, aromatic modified terpene resins, terpene phenols Terpene resins such as pentene resins; hydrogenated terpene resins obtained by hydrogenating these terpene resins; copolymerization of C5 fractions such as pentene, isoprene, piperine, 1.3-pentadiene produced by thermal decomposition of petroleum naphtha C5 petroleum resin obtained and hydrogenated petroleum resin of this C5 petroleum resin; obtained by copolymerization of C9 fraction such as indene, vinyltoluene, ⁇ - or ⁇ -methylstyrene generated by thermal decomposition of petroleum naphtha C9 petroleum resin and hydrogenated petroleum resin of this C9 petroleum resin.
  • the tackifiers may be used alone or in combination of
  • the content of the tackifier in the adhesive composition is preferably 1 to 200 parts by weight, more preferably 5 to 160 parts by weight, and still more preferably 10 to 120 parts by weight with respect to 100 parts by weight of the adhesive resin (A). Part by mass.
  • the adhesive resin (A) contains an acrylic resin
  • the content of the tackifier is preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass with respect to 100 parts by mass of the acrylic resin. Part, more preferably 10 to 40 parts by weight.
  • the adhesive resin (A) contains a urethane resin
  • the content of the tackifier is preferably 5 to 200 parts by mass, more preferably 40 to 160 parts by mass with respect to 100 parts by mass of the urethane resin.
  • the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 10 to 80 parts by mass, with respect to 100 parts by mass of the PIB resin. More preferably, it is 15 to 40 parts by mass.
  • the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 15 to 80 parts by mass with respect to 100 parts by mass of the polyester resin. More preferably, it is 25 to 60 parts by mass.
  • the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 15 to 80 parts by mass with respect to 100 parts by mass of the polyolefin resin. More preferably, it is 25 to 60 parts by mass.
  • the pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a crosslinking agent.
  • a crosslinking agent In particular, when the above-mentioned acrylic resin (particularly, the acrylic resin having the above-mentioned functional group) is used as the adhesive resin (A), crosslinking is performed from the viewpoint of improving the adhesive strength of the formed adhesive layer. It is preferable to contain an agent.
  • the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, a metal chelate crosslinking agent, an amine crosslinking agent, and an amino resin crosslinking agent. These crosslinking agents may be used alone or in combination of two or more. Among these, from the viewpoint of improving the adhesive strength of the conductive adhesive sheet, an isocyanate-based crosslinking agent is preferable.
  • isocyanate-based crosslinking agent examples include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4′-diisocyanate, Polyvalent isocyanate compounds such as diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate Is mentioned.
  • the polyvalent isocyanate compound may be a trimethylolpropane adduct type modified product of the above compound, a burette type modified product reacted with water, or an isocyanurate type modified product containing an isocyanurate ring.
  • the content of the crosslinking agent in the adhesive composition is preferably 0.01 to 15 parts by mass, more preferably 0.05 to 10 parts by mass, and still more preferably 100 parts by mass of the adhesive resin (A). 0.1 to 5 parts by mass.
  • the pressure-sensitive adhesive composition which is a material for forming the pressure-sensitive adhesive layer may further contain a curing accelerator.
  • a curing accelerator when the above-mentioned silyl group-containing urethane resin is contained as the adhesive resin (A), the crosslinking reaction between the silyl groups of the silyl group-containing urethane resin is promoted, and the pressure-sensitive adhesive composition is crosslinked. From the viewpoint of further improving the physical properties, it is preferable to contain a curing accelerator.
  • this hardening accelerator (E) functions as a catalyst.
  • the curing accelerator is preferably one or more selected from the group consisting of an aluminum catalyst, a titanium catalyst, a zirconium catalyst, and a boron trifluoride catalyst.
  • aluminum catalyst aluminum alkoxide, aluminum chelate, and aluminum chloride (III) are preferable.
  • titanium-based catalyst titanium alkoxide, titanium chelate, and titanium (IV) chloride are preferable.
  • zirconium-based catalyst zirconium alkoxide, zirconium chelate, and zirconium (IV) chloride are preferable.
  • boron trifluoride-based catalyst an amine complex of boron trifluoride such as boron trifluoride monoethylamine complex or an alcohol complex is preferable.
  • the content of the curing accelerator is preferably 0.001 to 20 parts by mass, more preferably 0.01 to 10 parts by mass, still more preferably 0.03 to 10 parts by mass with respect to 100 parts by mass of the adhesive resin (A). 5 parts by mass.
  • the pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a crosslinking aid.
  • a crosslinking aid in particular, when the above-mentioned silyl group-containing urethane resin is contained as the adhesive resin (A), it is preferable to contain a crosslinking aid in combination with the above-described curing accelerator.
  • the crosslinking aid amino group-containing alkoxysilanes are preferred.
  • amino group-containing alkoxysilane examples include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, and N-2- (aminoethyl). ) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and the like.
  • the content of the crosslinking aid is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 6 parts by weight, still more preferably 0.1 to 3 parts by weight based on 100 parts by weight of the adhesive resin (A). Part by mass.
  • the pressure-sensitive adhesive composition which is a material for forming the pressure-sensitive adhesive layer, may contain general-purpose additives used for general pressure-sensitive adhesives as long as the effects of the present invention are not impaired.
  • general-purpose additives include ultraviolet absorbers, antioxidants, softeners (plasticizers), fillers, rust inhibitors, pigments, and dyes.
  • the amount of each general-purpose additive is preferably 0.01 to 6 parts by mass, more preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the adhesive resin (A). 2 parts by mass.
  • the occupation area ratio of the carbon-based filler (B) on the adhesive surface of the pressure-sensitive adhesive layer is within the above range, and the carbon-based filler (B) Can be easily adjusted by appropriately combining the following items [1] to [5].
  • the items [1] to [5] below are merely examples, and it is naturally possible to make adjustments based on general technical common sense other than the items.
  • the pressure-sensitive adhesive layer is prepared by mixing the adhesive resin (A) with the dispersion of the carbon-based filler (b) prepared by applying ultrasonic vibration, and then stirring with a stirrer. It is a layer formed from the adhesive composition.
  • the mixture of the carbon filler (b) dispersion and the adhesive resin (A) is manually stirred, the presence of the adhesive resin (A) causes the carbon filler (b) to be uniformly dispersed.
  • the carbon-based fillers (b) are too close to each other and tend to form aggregates.
  • process (1) and "process (2)” regarding the manufacturing method of the electroconductive adhesive sheet mentioned later. The matter is as follows.
  • a carbon filler having an average aspect ratio in the above range is used as the carbon filler (b) before dispersion.
  • the adhesive resin (A) an adhesive resin having a mass average molecular weight belonging to the above range is used.
  • the adhesive resin (A) one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins are used. More detailed aspects of the acrylic resin and the urethane resin are as described above.
  • the carbon-based filler (b) it is preferable to use a carbon-based filler having a shape formed by a fibrous material in which a plurality of single yarns are entangled, such as wool, and the plurality of single yarns are entangled. It is more preferable to use a cylindrical carbon-based filler formed of a fibrous material. By using such a carbon-based filler, it is easy to form a network network in the process of forming the pressure-sensitive adhesive layer, and it is easy to adjust the occupation area ratio of the carbon-based filler (B) on the pasting surface to the above range. .
  • the base material used for the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is appropriately selected according to the purpose of use of the conductive pressure-sensitive adhesive sheet.
  • the electroconductive base material containing the electroconductive material of this may be sufficient.
  • an insulating substrate refers to a substrate having a surface resistivity of 1.0 ⁇ 10 14 ⁇ / ⁇ or more (preferably 1.0 ⁇ 10 16 ⁇ / ⁇ or more).
  • the insulating base material include various types of paper such as fine paper, art paper, coated paper, glassine paper, and laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials; Material: Polyolefin resin such as polyethylene resin and polypropylene resin, Polybutylene terephthalate resin, Polyester resin such as polyethylene terephthalate resin, Plastic film or sheet made of acetate resin, ABS resin, polystyrene resin, vinyl chloride resin, etc .; Mixture of these resins A plastic film or sheet comprising: a plastic film or sheet comprising a laminate of these plastic films or sheets.
  • the base material such as a plastic film or sheet may be unstretched, or may be stretched in a uniaxial direction or a biaxial direction such as longitudinal or lateral.
  • These insulating base materials may further contain an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an antiblocking agent, a colorant, and the like.
  • the conductive substrate examples include a metal foil, a film or sheet obtained by laminating the metal foil with a resin or the like that forms the above-described insulating substrate, and a film obtained by performing a metal deposition process on the surface of the above-described insulating substrate.
  • seat which knitted the metal wire in mesh shape, etc. are mentioned.
  • a metal used for an electroconductive base material aluminum, copper, silver, gold
  • the thickness of the substrate is not particularly limited, but is preferably 10 to 250 ⁇ m, more preferably 15 to 200 ⁇ m, and still more preferably 20 to 150 ⁇ m from the viewpoint of ease of handling.
  • the surface of the base material is subjected to a surface treatment such as an oxidation method or an unevenness method as necessary.
  • the oxidation method is not particularly limited, and examples thereof include a corona discharge treatment method, a plasma treatment method, chromic acid oxidation (wet), flame treatment, hot air treatment, and ozone / ultraviolet irradiation treatment.
  • a corona discharge treatment method for example, a plasma treatment method, chromic acid oxidation (wet), flame treatment, hot air treatment, and ozone / ultraviolet irradiation treatment.
  • corrugated method For example, a sandblasting method, a solvent processing method, etc. are mentioned.
  • These surface treatments are appropriately selected according to the type of the substrate, but the corona discharge treatment method is preferred from the viewpoint of improving the adhesion with the pressure-sensitive adhesive layer and operability.
  • primer treatment can also be performed.
  • peeling sheet used for the electroconductive adhesive sheet of 1 aspect of this invention, the peeling sheet by which the double-sided peeling process was carried out, the peeling sheet by which the single-sided peeling process was carried out, etc. are used, and it peels on the base material for peeling sheets. The thing etc. which apply
  • Examples of the base material for the release sheet include paper base materials such as glassine paper, coated paper, and high-quality paper, laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials, or polyethylene terephthalate resin, polybutylene. Examples thereof include polyester resin films such as terephthalate resin and polyethylene naphthalate resin, and plastic films such as polyolefin resin films such as polypropylene resin and polyethylene resin.
  • Examples of the release agent include rubber elastomers such as silicone resins, olefin resins, isoprene resins, and butadiene resins, long chain alkyl resins, alkyd resins, and fluorine resins.
  • the thickness of the release sheet is not particularly limited, but is preferably 10 to 200 ⁇ m, more preferably 25 to 150 ⁇ m.
  • a pressure-sensitive adhesive composition is prepared by blending the above-described components, and further diluted by adding an organic solvent to form a pressure-sensitive adhesive composition solution. And a method of producing the adhesive layer by forming the solution on the above-mentioned substrate or release sheet by known coating and drying.
  • the method for producing the conductive pressure-sensitive adhesive sheet of the present invention includes the following steps (1) to A production method having (3) is preferred.
  • Step (1) A step of preparing a dispersion of the carbon-based filler (b) by applying vibration by ultrasonic waves.
  • -Process (2) The process which mixes adhesive resin (A) with the dispersion liquid obtained at the process (1), and prepares an adhesive composition by stirring using the stirrer which has a stirring blade.
  • -Process (3) The process of forming an adhesive layer using the adhesive composition obtained at the process (2).
  • Step (1) is a step of preparing a dispersion liquid of carbon-based filler (b) by applying vibration by ultrasonic waves.
  • the carbon-based filler (b) is preferably mixed with a component such as an adhesive resin (A) after being in the form of a dispersion liquid dispersed in a solvent.
  • a component such as an adhesive resin (A) after being in the form of a dispersion liquid dispersed in a solvent.
  • Examples of the solvent used for the preparation of the carbon filler (b) dispersion include water and organic solvents, with organic solvents being preferred.
  • Examples of the organic solvent used for the preparation of the carbon filler (b) dispersion include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, 1-propanol, isopropyl alcohol, and dimethylformamide. N-methylpyrrolidone, dimethyl sulfoxide and the like. These organic solvents may be used alone or in combination of two or more.
  • At least one selected from methyl ethyl ketone, ethyl acetate, toluene, and isopropyl alcohol is preferable, and at least one selected from ethyl acetate and isopropyl alcohol is more preferable.
  • the carbon-based filler (b) is added to the solvent, and the vibration of the ultrasonic wave (the amplitude is preferably 1 to 50 ⁇ m, more preferably 5 to 40 ⁇ m) is given for a certain period of time.
  • a dispersion of (b) is prepared.
  • the carbon-based fillers (b) are close to each other in the dispersion and moderately (non-string aggregates are not formed. To a degree). As a result, it becomes easy to form a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is dispersed.
  • the solid content concentration of the carbon filler (b) dispersion is preferably 0.01 to 60% by mass, more preferably 0.05 to 10% by mass, and still more preferably 0.1 to 3% by mass.
  • step (2) an adhesive resin (A) or the above-mentioned other additive was blended into the carbon-based filler (b) dispersion obtained in step (1), and a stirrer having a stirring blade was used.
  • a stirrer having a stirring blade was used.
  • This is a step of preparing an adhesive composition by stirring. In this step, when the adhesive resin (A) and other additives are added to the dispersion of the carbon-based filler (b), an organic solvent is further added and diluted to form a solution of the adhesive composition It is good.
  • organic solvent used for preparing the adhesive composition examples include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, 1-propanol, isopropyl alcohol, dimethylformamide, N-methylpyrrolidone. And dimethyl sulfoxide. These organic solvents may be used alone or in combination of two or more.
  • the organic solvent used in the synthesis of the adhesive resin (A) or the organic solvent used when the carbon-based filler (b) is prepared in the form of a dispersion may be used as it is. More than one organic solvent other than the organic solvent used in the dispersion of the carbon-based filler (b) or during the synthesis of the adhesive resin (A) component so that the resulting adhesive composition solution can be uniformly applied An organic solvent may be added.
  • the solid content concentration of the adhesive composition solution is preferably 1 to 90% by mass, more preferably 3 to 80% by mass, still more preferably 5 to 70% by mass, and even more preferably 7 to 60% by mass. .
  • the adhesive resin (A) is blended with the dispersion liquid of the carbon-based filler (b) and mixed by stirring using a stirrer having a stirring blade to prepare an adhesive composition.
  • the carbon fillers (b) are uniformly close to each other in the pressure-sensitive adhesive composition, and moderately (to the extent that non-string aggregates are not formed). Aggregates easily. As a result, it becomes easy to form a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is dispersed.
  • the rotation speed of the stirring blade of the stirrer when stirring by the stirrer is preferably 500 to 10,000 rpm, more preferably 1000 to 5000 rpm, still more preferably 1200 to 3500 rpm, and still more preferably 1500 to 3000 rpm.
  • the average aspect ratio is relatively large as the carbon-based filler (b) before dispersion.
  • the rotational speed of the stirring blade is preferably relatively high, and specifically, 3000 rpm or more is preferable.
  • the rotation speed of the stirring blade is preferably relatively slow. Is preferably 1500 rpm or less.
  • Step (3) is a step of forming a pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition obtained in step (2).
  • the pressure-sensitive adhesive layer can be formed by applying a pressure-sensitive adhesive composition on a substrate or a release material to form a coating film, and then drying the coating film.
  • Examples of the method for applying the adhesive composition onto the substrate or release sheet include spin coating, spray coating, bar coating, knife coating, roll knife coating, roll coating, blade coating, and die coating. Method, gravure coating method and the like.
  • drying the drying treatment it is preferable to dry at a drying temperature of 25 to 150 ° C. (preferably 50 to 120 ° C.) for 10 seconds to 50 minutes (preferably 30 seconds to 30 minutes). Further, in order to increase the cohesive strength of the pressure-sensitive adhesive layer, after the drying treatment, for example, it is allowed to stand in an environment of 23 ° C. and 50% RH (relative humidity) for about 7 days to 30 days. It is preferable to sufficiently crosslink the pressure-sensitive adhesive layer (coating film).
  • the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is produced by appropriately bonding the base material or release sheet onto the pressure-sensitive adhesive layer as necessary. be able to.
  • the adhesive strength of the conductive adhesive sheet of one embodiment of the present invention is preferably 5.0 N / 25 mm or more, more preferably 7.0 N / 25 mm or more, still more preferably 10.0 N / 25 mm or more, and still more preferably 15 0.0 N / 25 mm or more.
  • the value of said adhesive force is an adhesive force when a to-be-adhered body is a stainless steel board, Comprising: The value measured by the method as described in an Example is meant.
  • the surface resistivity of the conductive adhesive sheet of one embodiment of the present invention is preferably 1.0 ⁇ 10 12 ⁇ / ⁇ or less, more preferably 1.0 ⁇ 10 10 ⁇ / ⁇ or less, more preferably 1.0 ⁇ . 10 9 ⁇ / ⁇ or less, more preferably 3.0 ⁇ 10 8 ⁇ / ⁇ or less, more preferably 1.0 ⁇ 10 7 ⁇ / ⁇ or less, and still more preferably 1.0 ⁇ 10 5 ⁇ / ⁇ or less. is there.
  • urethane resin (1) a resin (hereinafter also referred to as “urethane resin (1)”).
  • the “urethane resin (1)” was synthesized by using N-aminoethyl- ⁇ -aminopropylmethyldimethoxysilane as a raw material for the silylating agent. As shown, a bifunctional silyl group has been introduced.
  • CNT (1) trade name "NC7000", manufactured by Nanosil, cylindrical multi-walled carbon nanotubes formed by a fibrous material in which a plurality of single yarns are intertwined, average aspect ratio before dispersion (H / L ): 200 (long side length (H): 2 ⁇ m, short side length (L): 10 nm).
  • CNT (2) trade name “PLT-CN22”, manufactured by BRANET, Inc., cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 100 (long side length (H ): 15 ⁇ m, short side length (L): 15 nm).
  • CNT (3) trade name “CVD-MWNT CM-95”, manufactured by Nanotechnology, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 1250 (length of long side) (H): 15 ⁇ m, short side length (L): 12 nm).
  • CNT (4) trade name “VGCF-H”, manufactured by Showa Denko KK, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 5.54 (long side length) (H): 6 ⁇ m, short side length (L): 150 nm).
  • CNT (5) trade name "C-150P”, manufactured by Bayer, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 133 (long side length (H): 2 ⁇ m, short side length (L): 15 nm).
  • CNT (6) trade name "K-nanos 100P”, manufactured by Korea Kumho Petrochemical, cylindrical multi-walled carbon nanotubes formed by a fibrous material in which a plurality of single yarns are intertwined, average aspect before dispersion Ratio (H / L): 200 (long side length (H): 2 ⁇ m, short side length (L): 10 nm).
  • Crosslinking agent trade name “Coronate L”, manufactured by Tosoh Corporation, isocyanate crosslinking agent, solid content concentration: 75 mass%.
  • “Curing accelerator” Boron trifluoride monoethylamine complex.
  • Crosslinking aid 3-aminopropyltrimethoxysilane.
  • Examples 1 to 4 and Comparative Examples 1 to 6 (1) Preparation of dispersion liquid of carbon-based filler A carbon-based filler of the type and solid content (solid content ratio with respect to 100 parts by mass of adhesive resin (solid content)) shown in Table 1 is added to ethyl acetate, and ultrasonic dispersion is performed. Of a carbon-based filler having a solid content concentration of 0.3 mass% by applying vibration with ultrasonic waves having an amplitude of 30 ⁇ m for 15 minutes using a machine (trade name “Ultrasonic Disperser for Testing GSD600AT” manufactured by Sonic Technology Co., Ltd.). A dispersion was prepared.
  • Comparative Examples 7-8 (1) Preparation of carbon-based filler dispersion A carbon-based filler of the type and solid content (solid content ratio with respect to 100 parts by mass (adhesive content) of the adhesive resin) shown in Table 1 is added to ethyl acetate, and 15 manually. The mixture was stirred for a minute to prepare a carbon-based filler dispersion having a solid concentration of 0.3% by mass.
  • Adhesive Composition Solution With respect to 100 parts by mass (solid content) of the “acrylic resin (2)”, 2.86 parts by mass of the carbon-based filler dispersion prepared in (1) above ( (Solid content ratio) and 2.1 parts by mass (solid content ratio) of the above-mentioned “crosslinking agent” were added and stirred manually for 10 minutes to prepare a solution of an adhesive composition having a solid content concentration of 10 mass%.
  • FIG. 5A is the digital image of Example 1
  • FIG. 5B is the digital image of Comparative Example 6.
  • the dispersion shape of the carbon-based filler in the pressure-sensitive adhesive layer is “string” if the string-like material can be confirmed from the digital image, and “aggregate” if the string-like material cannot be confirmed and only the aggregate. It was judged.
  • ⁇ Adhesive strength of conductive adhesive sheet The produced conductive adhesive sheet was cut into a size of 5 mm ⁇ 300 mm as a test piece, and the release sheet of the test piece was removed and exposed in an environment of 23 ° C. and 50% RH (relative humidity).
  • the pressure-sensitive adhesive layer was attached to a stainless steel plate (SUS304, No. 360 polishing) and allowed to stand for 24 hours in the same environment. After standing, in accordance with JIS Z0237: 2000, the adhesive strength when the test piece was peeled from the stainless steel plate at a pulling speed of 300 mm / min was measured by a 180 ° peeling method.
  • ⁇ Surface resistivity of conductive adhesive sheet> The measurement was performed according to JIS K 7194. Specifically, the produced conductive adhesive sheet was cut into a size of 20 mm ⁇ 40 mm and allowed to stand for 24 hours in an environment of 23 ° C. and 50% RH (relative humidity). The surface resistivity was measured using a low resistivity meter (product name: “Loresta GP MCP-T610”, manufactured by Mitsubishi Chemical Analytech Co., Ltd.) did. The surface resistivity was measured three times, and Table 1 shows the average value of the three times.
  • the area ratio of the carbon-based filler in a specific region in plan view is within a predetermined range when the adhesive surface of the adhesive layer is viewed in plan view. It can be seen that the surface resistivity is lower than that of the conductive adhesive sheets of Comparative Examples 1 to 8.
  • the carbon-based filler is dispersed in a string shape in the pressure-sensitive adhesive layer.
  • the carbon-based filler was dispersed in the form of a string, as in the digital image shown in FIG. 5 (a). .
  • the carbon-based filler aggregates in the pressure-sensitive adhesive layer to form a non-string-like aggregate having no string-like material and dispersed. Yes.
  • the value of the occupied area ratio of the carbon-based filler when the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan is small.
  • the conductive pressure-sensitive adhesive sheet of the present invention is excellent in antistatic property and conductivity because of having good adhesive force and low surface resistivity. Therefore, the conductive pressure-sensitive adhesive sheet of the present invention prevents, for example, ignition due to sparks generated from static electricity such as electromagnetic shielding materials for containers for storing electronic devices such as computers and communication devices, grounding wires for electrical components, and even triboelectricity. It is suitable as a joining member used for members such as materials.

Abstract

Provided is an electroconductive pressure-sensitive adhesive sheet which comprises a pressure-sensitive adhesive layer that comprises a pressure-sensitive adhesive resin (A) and a carbon-based filler (B), wherein the pressure-sensitive adhesive layer has a carbon-based filler (B) content of 0.01-20 mass% relative to the total mass of the pressure-sensitive adhesive layer. When the adhesive surface of the pressure-sensitive adhesive layer is viewed from the plan-view direction, the proportion of the area occupied by the carbon-based filler (B) in any region selected from the adhesive surface is 17% or higher. The electroconductive pressure-sensitive adhesive sheet has satisfactory adhesive force and is excellent in terms of antistatic property and electroconductivity.

Description

導電性粘着シートConductive adhesive sheet
　本発明は、導電性粘着シートに関する。 The present invention relates to a conductive adhesive sheet.
　従来から、コンピューター、通信機器等の電子機器を収納する容器の電磁遮蔽材、電気部品等の接地線、更には摩擦電気等の静電気から生ずる火花による発火防止材等の各種接合には、簡易接着性を有する導電性粘着シートが使用されている。 Conventionally, simple bonding is used for various types of joints such as electromagnetic shielding materials for containers for storing electronic devices such as computers and communication devices, grounding wires for electrical components, and materials for preventing ignition caused by static electricity such as triboelectricity. A conductive pressure-sensitive adhesive sheet is used.
　導電性粘着シートが有する粘着剤層に用いられる粘着性組成物には、帯電防止性及び導電性を付与するために、銅粉、銀粉、ニッケル粉、アルミニウム粉等の金属粉等の導電性物質を、粘着性樹脂中に分散させたものが多用されている。 Conductive substances such as copper powder, silver powder, nickel powder, aluminum powder, and other metal powders are used for the pressure-sensitive adhesive composition used in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet. Are widely used in which they are dispersed in an adhesive resin.
　例えば、特許文献１には、アクリル系やゴム系の粘着剤中に、導電性物質であるカーボンナノチューブ及びカーボンマイクロコイルの少なくとも一方を、ロール混練機等を用いて分散させた導電性粘着剤、及び当該導電性粘着剤を用いた導電性粘着シートが開示されている。 For example, Patent Document 1 discloses a conductive pressure-sensitive adhesive in which at least one of carbon nanotubes and carbon microcoils, which are conductive materials, is dispersed in an acrylic or rubber-based pressure-sensitive adhesive using a roll kneader or the like, And the electroconductive adhesive sheet using the said electroconductive adhesive is disclosed.
特開２００１－１７２５８２号公報JP 2001-172582 A
　ところで、上記の導電性粘着シートが有する粘着剤層の導電性を向上させるためには、粘着剤層の形成材料である粘着性組成物中に導電性物質を多量に配合して、導電性物質粒子の相互の接触が密になるようにする必要がある。
　しかしながら、粘着性組成物中に、多量の導電性物質を配合すると、被着体に対する粘着力や基材に対する密着性が低下する傾向にある。また、一般的な導電性物質は粘着性組成物に比べて比重が大きいため、多量に配合すると電子機器の軽量化の妨げとなる。一方で、粘着力を高めるために導電性物質の含有量を低減させると、導電性が低下するという、二律背反の問題がある。 By the way, in order to improve the conductivity of the pressure-sensitive adhesive layer possessed by the above-mentioned conductive pressure-sensitive adhesive sheet, a large amount of a conductive material is blended in the pressure-sensitive adhesive composition that is the material for forming the pressure-sensitive adhesive layer, It is necessary to have close contact between the particles.
However, when a large amount of a conductive material is blended in the adhesive composition, the adhesive strength to the adherend and the adhesiveness to the substrate tend to be lowered. Further, since a general conductive material has a higher specific gravity than an adhesive composition, if it is added in a large amount, it will hinder weight reduction of an electronic device. On the other hand, when the content of the conductive material is reduced in order to increase the adhesive strength, there is a trade-off problem that the conductivity is lowered.
　また、本発明者らの検討によれば、特許文献１に開示された導電性粘着シートは、導電性が十分に向上されない場合があり、安定して導電性を発現させることが難しいことが判明した。
　なお、多量の導電性物質を配合することで、導電性を向上させることも可能であるが、上述のとおり粘着力の低下という問題が生じる。 Further, according to the study by the present inventors, it has been found that the conductive adhesive sheet disclosed in Patent Document 1 may not be sufficiently improved in conductivity and it is difficult to stably develop conductivity. did.
In addition, although it is possible to improve electroconductivity by mix | blending a large amount of electroconductive substances, the problem that the adhesive force falls as mentioned above arises.
　本発明は、良好な粘着力を有すると共に、帯電防止性及び導電性に優れた導電性粘着シートを提供することを目的とする。 An object of the present invention is to provide a conductive pressure-sensitive adhesive sheet having good adhesive strength and excellent antistatic properties and conductivity.
　本発明者らは、導電性粘着シートの粘着剤層中の炭素系フィラーの分散状態に着目し、当該粘着剤層の貼付表面における炭素系フィラーの占有面積率を所定の範囲に調整することで、上記課題を解決し得ることを見出し、本発明を完成させた。
　すなわち、本発明は、下記〔１〕～〔１１〕を提供するものである。
〔１〕粘着性樹脂（Ａ）及び炭素系フィラー（Ｂ）を含む粘着剤層を有する導電性粘着シートであって、
　前記粘着剤層中の炭素系フィラー（Ｂ）の含有量が、前記粘着剤層の全質量に対して、０．０１～２０質量％であり、
　前記粘着剤層の貼付表面を平面視した際に、当該貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）の占有面積率が１７％以上である、導電性粘着シート。
〔２〕前記粘着剤層が、超音波による振動を与えて調製された、炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）を配合した後、撹拌機を用いた撹拌により調製された粘着性組成物から形成された層である、上記〔１〕に記載の導電性粘着シート。
〔３〕前記粘着剤層中において、炭素系フィラー（Ｂ）がひも状に分散しており、
　前記粘着剤層中をひも状に分散している炭素系フィラー（Ｂ）の太さの平均が０．５～５．０μｍであり、且つ平均アスペクト比が３．０以上である、上記〔１〕又は〔２〕に記載の導電性粘着シート。
〔４〕前記粘着剤層の貼付表面を平面視した際に、当該貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）が占める全占有面積に対する、炭素系フィラー（Ｂ）が凝集してなる短径４μｍ以上の非ひも状凝集体の含有率が５０％以下である、上記〔１〕～〔３〕のいずれか１項に記載の導電性粘着シート。
〔５〕炭素系フィラー（Ｂ）が、カーボンナノ材料である、上記〔１〕～〔４〕のいずれか１項に記載の導電性粘着シート。
〔６〕粘着性樹脂（Ａ）が、アクリル系樹脂及びウレタン系樹脂からなる群より選ばれる１種以上の粘着性樹脂を含む、上記〔１〕～〔５〕のいずれか１項に記載の導電性粘着シート。
〔７〕前記粘着剤層中の炭素系フィラー（Ｂ）の含有量が、前記粘着剤層の全質量に対して、０．１～７質量％である、上記〔１〕～〔６〕のいずれか１項に記載の導電性粘着シート。
〔８〕表面抵抗率が１．０×１０１０Ω／□以下である、上記〔１〕～〔７〕のいずれか１項に記載の導電性粘着シート。
〔９〕粘着力が５．０Ｎ／２５ｍｍ以上である、上記〔１〕～〔８〕のいずれか１項に記載の導電性粘着シート。
〔１０〕上記〔１〕～〔９〕のいずれか１項に記載の導電性粘着シートを製造する方法であって、
　下記工程（１）～（３）を有する、導電性粘着シートの製造方法。
工程（１）：超音波による振動を与えて、炭素系フィラー（ｂ）の分散液を調製する工程
工程（２）：工程（１）で得た分散液に、粘着性樹脂（Ａ）を配合し、撹拌翼を有する撹拌機を用いた撹拌により粘着性組成物を調製する工程
工程（３）：工程（２）で得た粘着性組成物を用いて粘着剤層を形成する工程
〔１１〕工程（２）において、前記撹拌機が有する撹拌翼の回転数が５００～１００００ｒｐｍである、上記〔１０〕の記載の導電性粘着シートの製造方法。 The present inventors pay attention to the dispersion state of the carbon-based filler in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet, and adjust the occupation area ratio of the carbon-based filler on the sticking surface of the pressure-sensitive adhesive layer to a predetermined range. The inventors have found that the above problems can be solved, and have completed the present invention.
That is, the present invention provides the following [1] to [11].
[1] A conductive adhesive sheet having an adhesive layer containing an adhesive resin (A) and a carbon-based filler (B),
The content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.01 to 20% by mass with respect to the total mass of the pressure-sensitive adhesive layer;
A conductive pressure-sensitive adhesive sheet, wherein when the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan, the occupation area ratio of the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface is 17% or more.
[2] After the adhesive resin (A) is blended with the dispersion of the carbon-based filler (b) prepared by applying vibration by ultrasonic waves, the adhesive layer is prepared by stirring using a stirrer The conductive pressure-sensitive adhesive sheet according to the above [1], which is a layer formed from the pressure-sensitive adhesive composition.
[3] In the pressure-sensitive adhesive layer, the carbon-based filler (B) is dispersed in a string shape,
The average thickness of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is 0.5 to 5.0 μm, and the average aspect ratio is 3.0 or more, [1 ] Or the conductive adhesive sheet according to [2].
[4] When the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan, the carbon-based filler (B) aggregates with respect to the total occupied area occupied by the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface. The conductive pressure-sensitive adhesive sheet according to any one of the above [1] to [3], wherein the content of the non-string aggregate having a minor axis of 4 μm or more is 50% or less.
[5] The conductive adhesive sheet according to any one of [1] to [4], wherein the carbon-based filler (B) is a carbon nanomaterial.
[6] The adhesive resin (A) according to any one of [1] to [5] above, wherein the adhesive resin (A) includes one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins. Conductive adhesive sheet.
[7] The content of the carbon filler (B) in the pressure-sensitive adhesive layer is 0.1 to 7% by mass with respect to the total mass of the pressure-sensitive adhesive layer, according to the above [1] to [6] The electroconductive adhesive sheet of any one of Claims.
[8] The conductive adhesive sheet according to any one of [1] to [7], wherein the surface resistivity is 1.0 × 10 10 Ω / □ or less.
[9] The conductive adhesive sheet according to any one of [1] to [8], wherein the adhesive strength is 5.0 N / 25 mm or more.
[10] A method for producing the conductive pressure-sensitive adhesive sheet according to any one of [1] to [9],
A method for producing a conductive pressure-sensitive adhesive sheet, comprising the following steps (1) to (3).
Step (1): Applying ultrasonic vibration to prepare a carbon-based filler (b) dispersion Step (2): Blending the adhesive resin (A) into the dispersion obtained in Step (1) Step (3) for preparing a pressure-sensitive adhesive composition by stirring using a stirrer having a stirring blade: Step [11] for forming a pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition obtained in step (2) The method for producing a conductive pressure-sensitive adhesive sheet according to the above [10], wherein in the step (2), the rotation speed of the stirring blade of the stirrer is 500 to 10,000 rpm.
　本発明の導電性粘着シートは、良好な粘着力を有すると共に、帯電防止性及び導電性に優れる。 The conductive pressure-sensitive adhesive sheet of the present invention has a good adhesive force and is excellent in antistatic properties and conductivity.
本発明の一態様の導電性粘着シートの構成の一例を示す、当該導電性粘着シートの断面図である。It is sectional drawing of the said conductive adhesive sheet which shows an example of a structure of the conductive adhesive sheet of 1 aspect of this invention. （ａ）本発明の一態様の導電性粘着シートが有する粘着剤層中の炭素系フィラー（Ｂ）の分散の様子を模式的に示した、粘着剤層の斜視図の一例であり、（ｂ）粘着剤層の貼付表面を平面視した際の当該貼付表面の平面図の一例である。(A) It is an example of the perspective view of the adhesive layer which showed typically the mode of dispersion | distribution of the carbon-type filler (B) in the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has, (b ) It is an example of a plan view of the sticking surface when the sticking surface of the adhesive layer is viewed in plan. 本発明の一態様の導電性粘着シートが有する粘着剤層中に分散している炭素系フィラー（Ｂ）の形状の一例を示した図である。It is the figure which showed an example of the shape of the carbonaceous filler (B) currently disperse | distributed in the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has. 本発明の一態様の導電性粘着シートが有する粘着剤層の貼付表面を平面視した際の当該貼付表面の平面図の一例である。It is an example of the top view of the said sticking surface when the sticking surface of the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has is planarly viewed. 実施例１及び比較例６で作製した導電性粘着シートの粘着剤層の貼付表面を平面視した際の、当該貼付表面の任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域を倍率２０００倍で撮影して取得したデジタル画像であって、（ａ）は実施例１のデジタル画像、（ｂ）は比較例６のデジタル画像である。When the pasting surface of the adhesive layer of the conductive adhesive sheet produced in Example 1 and Comparative Example 6 is viewed in plan, an arbitrarily selected 10,000 μm 2 (a square whose side is 100 μm in length) is selected. 2A is a digital image obtained by photographing an area at a magnification of 2000 times, where FIG. 4A is a digital image of Example 1 and FIG. 4B is a digital image of Comparative Example 6; 実施例１～４で作製した導電性粘着シートの粘着剤層の貼付表面を平面視した際の、当該貼付表面の任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域を倍率２０００倍で撮影して取得したデジタル画像を２値化して得た、２値化画像であって、（ａ）は実施例１、（ｂ）は実施例２、（ｃ）は実施例３、及び（ｄ）は実施例４の２値化画像である。When the adhesive surface of the adhesive layer of the conductive adhesive sheet prepared in Examples 1 to 4 was viewed in plan, an arbitrarily selected region of 10,000 μm 2 (a square with a side length of 100 μm) was selected. A binarized image obtained by binarizing a digital image obtained by photographing at a magnification of 2000 times, (a) in Example 1, (b) in Example 2, and (c) in Example 3. , And (d) are binarized images of Example 4. 比較例１～８で作製した導電性粘着シートの粘着剤層の貼付表面を平面視した際の、当該貼付表面の任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域を倍率２０００倍で撮影して取得したデジタル画像を２値化して得た、２値化画像であって、（ａ）は比較例１、（ｂ）は比較例２、（ｃ）は比較例３、（ｄ）は比較例４、（ｅ）は比較例５、（ｆ）は比較例６、（ｇ）は比較例７、及び（ｈ）は比較例８の２値化画像である。When the adhesive surface of the adhesive layer of the conductive adhesive sheet prepared in Comparative Examples 1 to 8 is viewed in plan, an arbitrarily selected region of 10,000 μm 2 (a square with a side length of 100 μm) is selected. A binarized image obtained by binarizing a digital image obtained by photographing at a magnification of 2000 times, (a) is Comparative Example 1, (b) is Comparative Example 2, and (c) is Comparative Example 3. , (D) is a comparative example 4, (e) is a comparative example 5, (f) is a comparative example 6, (g) is a comparative example 7, and (h) is a binary image.
　本明細書において、「質量平均分子量（Ｍｗ）」は、ゲルパーミエーションクロマトグラフィー（ＧＰＣ）法で測定される標準ポリスチレン換算の値であり、具体的には実施例に記載の方法に基づいて測定した値である。
　また、例えば「（メタ）アクリレート」とは、「アクリレート」及び「メタクリレート」の双方を示す語として用いており、他の類似用語についても同様である。
　さらに、「置換もしくは無置換」との語の「無置換」とは、置換基によって置換されておらず、水素原子が結合していることを意味する。
　なお、本明細書の以下の記載の中の「導電性粘着シートの表面抵抗率」とは、特に断りが無い限り、導電性粘着シートが有する粘着剤層の貼付表面を表出させ、当該貼付表面側から測定した表面抵抗率を意味し、具体的な測定方法は、実施例に記載のとおりである。 In the present specification, “mass average molecular weight (Mw)” is a value in terms of standard polystyrene measured by gel permeation chromatography (GPC), and specifically measured based on the method described in Examples. It is the value.
For example, “(meth) acrylate” is used as a term indicating both “acrylate” and “methacrylate”, and the same applies to other similar terms.
Further, the term “unsubstituted” in the term “substituted or unsubstituted” means that a hydrogen atom is bonded without being substituted by a substituent.
In the following description of the present specification, the “surface resistivity of the conductive adhesive sheet” means that the adhesive layer of the conductive adhesive sheet is exposed, unless otherwise specified. The surface resistivity measured from the surface side is meant, and a specific measuring method is as described in the examples.
〔導電性粘着シートの構成〕
　本発明の導電性粘着シートは、粘着性樹脂（Ａ）及び炭素系フィラー（Ｂ）を含む粘着剤層を有する構成であれば特に制限はなく、当該粘着剤層以外の他の層を有していてもよい。
　図１は、本発明の一態様の導電性粘着シートの構成の一例を示す、当該導電性粘着シートの断面図である。
　本発明の一態様の導電性粘着シートとしては、例えば、図１（ａ）に示すような、基材１２上に、粘着剤層１１が積層した構成を有する導電性粘着シート１ａが挙げられる。
　なお、導電性粘着シート１ａの構成に対して、図１（ｂ）に示すように、粘着剤層１１上に、更に剥離シート１３を積層した構成を有する導電性粘着シート１ｂとしてもよい。 [Configuration of conductive adhesive sheet]
If the conductive adhesive sheet of this invention is a structure which has an adhesive layer containing an adhesive resin (A) and a carbonaceous filler (B), there will be no restriction | limiting, and it has other layers other than the said adhesive layer. It may be.
FIG. 1 is a cross-sectional view of the conductive pressure-sensitive adhesive sheet showing an example of the configuration of the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention.
Examples of the conductive pressure-sensitive adhesive sheet according to one embodiment of the present invention include a conductive pressure-sensitive adhesive sheet 1a having a configuration in which a pressure-sensitive adhesive layer 11 is laminated on a substrate 12 as shown in FIG.
In addition, it is good also as the electroconductive adhesive sheet 1b which has the structure which laminated | stacked the peeling sheet 13 on the adhesive layer 11, as shown in FIG.1 (b) with respect to the structure of the electroconductive adhesive sheet 1a.
　さらに、本発明の別の一態様の導電性粘着シートとしては、例えば、図１（ｃ）に示すような、基材の両面上にそれぞれ粘着剤層１１、１１’が積層し、更に粘着剤層１１、１１’上に、それぞれ剥離シート１３、１３’が積層した構成を有する導電性粘着シート１ｃも挙げられる。
　なお、導電性粘着シート１ｃが有する粘着剤層１１及び粘着剤層１１’は、同じ種類の粘着性組成物から形成される層であってもよく、互いに異なる種類の粘着性組成物から形成される層であってもよい。 Furthermore, as another example of the conductive pressure-sensitive adhesive sheet of the present invention, pressure-sensitive adhesive layers 11 and 11 ′ are respectively laminated on both surfaces of a base material as shown in FIG. The electroconductive adhesive sheet 1c which has the structure which the peeling sheets 13 and 13 'laminated | stacked on the layers 11 and 11', respectively is mentioned.
The pressure-sensitive adhesive layer 11 and the pressure-sensitive adhesive layer 11 ′ of the conductive pressure-sensitive adhesive sheet 1c may be layers formed from the same type of pressure-sensitive adhesive composition, and are formed from different types of pressure-sensitive adhesive compositions. It may be a layer.
　また、本発明の一態様の導電性粘着シートとしては、基材無し導電性粘着シートであってもよい。このような基材無し導電性粘着シートとしては、例えば、図１（ｄ）に示すような、粘着剤層１１を２枚の剥離シート１３、１３’により挟持した構成を有する導電性粘着シート１ｄが挙げられる。
　また、本発明の一態様に含まれる基材無し導電性粘着シートとしては、両面が剥離処理された剥離シートの片面に、粘着剤層を設けたものをロール状に巻いた構成を有する導電性粘着シート等も挙げられる。 Further, the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention may be a substrate-less conductive pressure-sensitive adhesive sheet. As such a baseless conductive adhesive sheet, for example, as shown in FIG. 1 (d), a conductive adhesive sheet 1d having a configuration in which an adhesive layer 11 is sandwiched between two release sheets 13, 13 ′. Is mentioned.
Moreover, as a base-material-free electroconductive adhesive sheet contained in one aspect | mode of this invention, the electroconductivity which has the structure which wound what provided the adhesive layer on the single side | surface of the peeling sheet by which both surfaces were peel-processed was rolled. An adhesive sheet etc. are also mentioned.
〔粘着剤層中の炭素系フィラー（Ｂ）の分散状態〕
　図２（ａ）は、本発明の一態様の導電性粘着シートが有する粘着剤層中の炭素系フィラー（Ｂ）の分散の様子を模式的に示した粘着剤層の斜視図の一例であり、図２（ｂ）は、図２（ａ）の粘着剤層１１の貼付表面１１ａを平面視した際の当該貼付表面１１ａの平面図の一例である。
　本発明の導電性粘着シートにおいて、当該導電性粘着シートが有する粘着剤層の貼付表面を平面視した際に、当該貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）の占有面積率（以下、「貼付表面上の炭素系フィラー（Ｂ）の占有面積率」ともいう）が１７％以上である。
　上記の「粘着剤層の貼付表面を平面視した際」とは、図１（ａ）及び図２（ａ）の粘着剤層の貼付表面１１ａをαの方向から観察する場合を意味している。
　なお、図１（ｂ）の導電性粘着シート１ｂ等のように、粘着剤層１１の貼付表面上に剥離シート１３を積層した構成の場合は、当該剥離シート１３を除去し、表出した粘着剤層１１の貼付表面を平面視した際に、貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）の占有面積率が１７％以上であればよい。
　また、図１（ｃ）の導電性粘着シート１ｃや図１（ｄ）の導電性粘着シート１ｄのように、剥離シートを除去した場合の、表出する粘着剤層の貼付表面が２つ存在する場合、それぞれの貼付表面上の炭素系フィラー（Ｂ）の占有面積率が１７％以上であればよい。 [Dispersion state of carbon-based filler (B) in the adhesive layer]
Fig.2 (a) is an example of the perspective view of the adhesive layer which showed typically the mode of dispersion | distribution of the carbon-type filler (B) in the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has. FIG. 2B is an example of a plan view of the pasting surface 11a when the pasting surface 11a of the pressure-sensitive adhesive layer 11 in FIG.
In the conductive pressure-sensitive adhesive sheet of the present invention, the area occupied by the carbon-based filler (B) in an arbitrarily selected region on the sticking surface when the sticking surface of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet is viewed in plan view The rate (hereinafter also referred to as “occupied area ratio of the carbon-based filler (B) on the pasting surface”) is 17% or more.
The above-mentioned “when the adhesive surface of the adhesive layer is viewed in plan” means that the adhesive surface 11a of the adhesive layer in FIGS. 1A and 2A is observed from the direction α. .
In the case of a configuration in which a release sheet 13 is laminated on the adhesive surface of the pressure-sensitive adhesive layer 11 as in the conductive adhesive sheet 1b in FIG. When the pasting surface of the agent layer 11 is viewed in plan, the occupation area ratio of the carbon-based filler (B) in an arbitrarily selected region on the pasting surface may be 17% or more.
In addition, there are two sticking surfaces of the adhesive layer to be exposed when the release sheet is removed, such as the conductive adhesive sheet 1c in FIG. 1 (c) and the conductive adhesive sheet 1d in FIG. 1 (d). When it does, the occupation area rate of the carbon-type filler (B) on each sticking surface should just be 17% or more.
　従来、例えば、特許文献１のように、粘着剤層の形成材料である粘着性組成物の調製に使用する導電性物質である炭素系フィラーの形状についての各種検討はされている。
　しかしながら、当該粘着性組成物から形成後の粘着剤層中の炭素系フィラーの分散状態については、これまで検討されてはいなかった。
　例えば、本発明者らの検討によれば、特許文献１に記載されたロール混練機等を用いた方法により、粘着性樹脂中に導電性物質を分散させると、導電性物質同士が互いに凝集し、いわゆる「ダマ」と呼ばれる凝集体を形成され易いという性質があることが分かった。その結果、得られる粘着シートの導電性が十分に向上されない。
　なお、この場合、多量の導電性物質を添加することで導電性を向上させることも可能であるが、導電性物質の添加量を増やすほど粘着力が低下する。 Conventionally, for example, as in Patent Document 1, various studies have been made on the shape of a carbon-based filler that is a conductive substance used for preparing a pressure-sensitive adhesive composition that is a material for forming a pressure-sensitive adhesive layer.
However, the dispersion state of the carbon-based filler in the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition has not been studied so far.
For example, according to the study by the present inventors, when a conductive material is dispersed in an adhesive resin by a method using a roll kneader described in Patent Document 1, the conductive materials aggregate with each other. It was found that there is a property that an aggregate called a “dama” is easily formed. As a result, the conductivity of the obtained pressure-sensitive adhesive sheet is not sufficiently improved.
In this case, it is possible to improve the conductivity by adding a large amount of a conductive material, but the adhesive force decreases as the amount of the conductive material added increases.
　本発明者らは、粘着性組成物から形成された粘着剤層中の炭素系フィラー（Ｂ）の分散状態に着目したところ、粘着剤層の貼付表面上の炭素系フィラー（Ｂ）の占有面積率と、導電性粘着シートの表面抵抗率との関係について、一定の関連性があることを突き止めた。
　本発明者らは、例えば、粘着剤層中の炭素系フィラー（Ｂ）がひも状に分散した状態であると、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が上昇し、導電性粘着シートの表面抵抗率が格段に向上することを発見し、当該発見を基にして、本発明を完成させたものである。 The present inventors paid attention to the dispersion state of the carbon-based filler (B) in the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition. The area occupied by the carbon-based filler (B) on the adhesive surface of the pressure-sensitive adhesive layer About the relationship between the rate and the surface resistivity of the conductive adhesive sheet, it was found that there is a certain relationship.
For example, when the carbon-based filler (B) in the pressure-sensitive adhesive layer is dispersed in a string shape, the inventors of the present invention increase the occupation area ratio of the carbon-based filler (B) on the pasting surface, and become conductive. It was discovered that the surface resistivity of the pressure-sensitive adhesive sheet was remarkably improved, and the present invention was completed based on the discovery.
　なお、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い場合、粘着剤層中の炭素系フィラー（Ｂ）の分散状態は、図２（ａ）に示すように、粘着剤層の貼付表面１１ａ付近に限らず、粘着剤層１１の内部にも一様に分散し、複数の炭素系フィラー（Ｂ）１５が互いに接触し、網目状のネットワークを形成していると考えられる。
　このように、粘着剤層１１の内部で、炭素系フィラー（Ｂ）が網目状のネットワークを形成することで、導電性粘着シートの表面抵抗率を効果的に低下させることができ、帯電防止性及び導電性に優れた導電性粘着シートとなり得ると推測される。 In addition, when the occupation area rate of the carbon-based filler (B) on the pasting surface is high, the dispersion state of the carbon-based filler (B) in the pressure-sensitive adhesive layer is as shown in FIG. It is considered that not only the vicinity of the pasting surface 11a but also the inside of the pressure-sensitive adhesive layer 11 is uniformly dispersed, and a plurality of carbon-based fillers (B) 15 are in contact with each other to form a network network.
Thus, the carbon-based filler (B) forms a network-like network inside the pressure-sensitive adhesive layer 11, so that the surface resistivity of the conductive pressure-sensitive adhesive sheet can be effectively reduced, and antistatic properties can be obtained. And it is estimated that it can become an electroconductive adhesive sheet excellent in electroconductivity.
　貼付表面１１ａを平面視すると、図２（ｂ）のように、貼付表面１１ａに複数の炭素系フィラー（Ｂ）１５が見られる。なお、貼付表面１１ａから視認できる炭素系フィラー（Ｂ）１５は、貼付表面１１ａ上もしくは貼付表面１１ａの表層部に必ずしも分散されているわけではなく、粘着剤層の内部に分散しているものも含まれる。つまり、粘着剤層の内部に分散している炭素系フィラー（Ｂ）についても、貼付表面１１ａを平面視した際に、貼付表面１１ａ上に視認できる状態であるに過ぎない。 When the pasting surface 11a is viewed in plan, a plurality of carbon-based fillers (B) 15 are seen on the pasting surface 11a as shown in FIG. The carbon-based filler (B) 15 that can be visually recognized from the pasting surface 11a is not necessarily dispersed on the pasting surface 11a or the surface layer portion of the pasting surface 11a, but may be dispersed inside the adhesive layer. included. That is, the carbon-based filler (B) dispersed inside the pressure-sensitive adhesive layer is only in a state that can be visually recognized on the pasting surface 11a when the pasting surface 11a is viewed in plan.
　図５（ａ）は、本実施例１で作製した導電性粘着シートの粘着剤層の貼付表面を平面視した際の、当該貼付表面上の任意に選択した領域を所定の倍率で撮影して取得したデジタル画像である。
　図５（ａ）のデジタル画像によれば、粘着剤層の貼付表面付近の炭素系フィラー（Ｂ）の輪郭は濃いが、貼付表面から離れるほど、炭素系フィラー（Ｂ）の輪郭は薄くなっていることが確認できる。
　本願においては、このデジタル画像を所定の閾値で２値化し、上記領域中の炭素系フィラー（Ｂ）の占有箇所を特定している（図６及び図７参照）。この炭素系フィラー（Ｂ）の占有箇所の割合（占有面積率）が、導電性粘着シートの表面抵抗率や粘着力に影響を与えると考えられる。 FIG. 5A is a photograph of an arbitrarily selected region on the sticking surface at a predetermined magnification when the sticking surface of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet produced in Example 1 is viewed in plan view. It is the acquired digital image.
According to the digital image of FIG. 5A, the outline of the carbon-based filler (B) in the vicinity of the application surface of the adhesive layer is dark, but the outline of the carbon-based filler (B) becomes thinner as the distance from the application surface increases. It can be confirmed.
In the present application, the digital image is binarized with a predetermined threshold value, and the occupied area of the carbon-based filler (B) in the region is specified (see FIGS. 6 and 7). It is considered that the ratio of occupied portions (occupied area ratio) of the carbon-based filler (B) affects the surface resistivity and adhesive strength of the conductive adhesive sheet.
　本発明の導電性粘着シートにおいて、貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）の占有面積率は、１７％以上であり、好ましくは２０～９９．９９９％、より好ましくは２５～９８％、より好ましくは３５～９０％、更に好ましくは４５～８５％、更に好ましくは５０～８０％、より更に好ましくは５５～７５％である。
　当該占有面積率が１７％未満であると、導電性粘着シートの表面抵抗率を低下させることが困難となるため好ましくない。一方、当該占有面積率を９９．９９９％以下とすることで、導電性粘着シートの粘着力を適度に維持することができる。
　なお、貼付表面上の炭素系フィラー（Ｂ）の占有面積率の値は、実施例に記載の方法により測定した値を意味する。また、当該占有面積率の値の調整法の一例としては、後述のとおりである。 In the conductive pressure-sensitive adhesive sheet of the present invention, the area occupied by the carbon-based filler (B) in an arbitrarily selected region on the pasting surface is 17% or more, preferably 20 to 99.999%, more preferably It is 25 to 98%, more preferably 35 to 90%, still more preferably 45 to 85%, still more preferably 50 to 80%, and still more preferably 55 to 75%.
If the occupied area ratio is less than 17%, it is difficult to reduce the surface resistivity of the conductive adhesive sheet, which is not preferable. On the other hand, the adhesive force of a conductive adhesive sheet can be maintained moderately by the said occupied area rate being 99.999% or less.
In addition, the value of the occupation area rate of the carbon-type filler (B) on the sticking surface means the value measured by the method as described in an Example. An example of a method for adjusting the value of the occupied area ratio is as described later.
　本発明の一態様において、図２に示すように、粘着剤層中において、炭素系フィラー（Ｂ）がひも状に分散していることが好ましい。
　本明細書において、「ひも状に分散している炭素系フィラー」（以下、「ひも状の炭素系フィラー」ともいう）とは、図３に示す炭素系フィラー（Ｂ）１５のように、長尺方向に所定の長さ（図３中のｘ）を有し、断面が多角形又は円形（楕円形も含む）であり、長尺方向に湾曲自在となっている状態の炭素系フィラーを意味する。
　また、当該「断面」とは、ひも状に分散している炭素系フィラーの任意の点における接線方向に対して、垂直に切断したときの断面（例えば、円柱の場合の径方向断面に相当）をいう。
　なお、本明細書において、粘着剤層中の炭素系フィラー（Ｂ）がひも状に分散しているか否かは、粘着剤層の貼付表面１１ａ上の任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域を、倍率２０００倍で撮影して得たデジタル画像から判断する。具体的な判断方法は、実施例に記載のとおりである。 In one embodiment of the present invention, as shown in FIG. 2, the carbon-based filler (B) is preferably dispersed in a string shape in the pressure-sensitive adhesive layer.
In the present specification, “a carbon-based filler dispersed in a string” (hereinafter, also referred to as a “string-like carbon-based filler”) is a long like carbon-based filler (B) 15 shown in FIG. Means a carbon-based filler having a predetermined length in the length direction (x in FIG. 3), a cross section of a polygon or a circle (including an ellipse), and being freely bendable in the length direction. To do.
In addition, the “cross section” is a cross section obtained by cutting perpendicularly to a tangential direction at an arbitrary point of the carbon-based filler dispersed in a string (for example, a radial cross section in the case of a cylinder). Say.
In the present specification, whether or not the carbon-based filler (B) in the pressure-sensitive adhesive layer is dispersed in a string is determined by arbitrarily selecting 10,000 μm 2 (length of one side) on the adhesive surface 11 a of the pressure-sensitive adhesive layer. Is determined from a digital image obtained by photographing at a magnification of 2000 times. A specific determination method is as described in the examples.
　本発明の一態様において、主に、粘着性組成物の調製に際し、原料として配合する炭素系フィラー（以下、「炭素系フィラー（ｂ）」ともいう）の種類、形状、及び含有量；粘着性樹脂（Ａ）の種類、分子量、含有量及び粘着性組成物の溶液の調製に用いる溶媒；炭素系フィラー（ｂ）の配合方法及び炭素系フィラー（ｂ）の分散液の調製に用いる溶媒；粘着性組成物の調製方法（撹拌方法）；を適宜選択することで、炭素系フィラー（Ｂ）をひも状に分散させた粘着剤層の形成が可能であるが、より具体的な調整法は後述のとおりである。 In one embodiment of the present invention, the type, shape, and content of a carbon-based filler (hereinafter, also referred to as “carbon-based filler (b)”) blended as a raw material in the preparation of the pressure-sensitive adhesive composition; Resin (A) type, molecular weight, content and solvent used for preparation of adhesive composition solution; carbon filler (b) blending method and carbon filler (b) dispersion liquid preparation; adhesive The pressure-sensitive adhesive layer in which the carbon-based filler (B) is dispersed in a string shape can be formed by appropriately selecting the preparation method (stirring method) of the adhesive composition; a more specific adjustment method will be described later. It is as follows.
　本発明の一態様において、粘着剤層中でひも状に分散している炭素系フィラー（Ｂ）の太さ（ｄ）の平均は、好ましくは０．３～５．０μｍ、より好ましくは０．４～４．０μｍ、更に好ましくは０．５～３．０μｍ、より更に好ましくは０．６～２．０μｍである。
　太さ（ｄ）の平均が０．３μｍ以上であれば、導電性粘着シートの表面抵抗率の低下させる効果を十分に発現させることができる。一方、太さ（ｄ）の平均が５．０μｍ以下であれば、複数のひも状に分散している炭素系フィラー（Ｂ）が互いに接触し易く、網目状のネットワークの形成が容易となる。その結果、導電性粘着シートの表面抵抗率を効果的に低下させることができる。 In one embodiment of the present invention, the average thickness (d) of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is preferably 0.3 to 5.0 μm, more preferably 0.00. The thickness is 4 to 4.0 μm, more preferably 0.5 to 3.0 μm, and still more preferably 0.6 to 2.0 μm.
If the average of thickness (d) is 0.3 micrometer or more, the effect of reducing the surface resistivity of a conductive adhesive sheet can fully be expressed. On the other hand, if the average thickness (d) is 5.0 μm or less, a plurality of carbon-based fillers (B) dispersed in a string form can easily come into contact with each other, and a network network can be easily formed. As a result, the surface resistivity of the conductive adhesive sheet can be effectively reduced.
　本明細書において、「ひも状に分散している炭素系フィラー（Ｂ）の太さ（ｄ）」とは、ひも状の炭素系フィラー（Ｂ）の任意の点における接線方向に対して垂直に切断したときの切断面のうち面積が最大となる切断面において、当該切断面が円又は楕円であれば、直径又は長径であり、当該切断面が多角形であれば、当該多角形の辺のうち最長の辺の長さを意味し、具体的には図３のｄの長さを指す。
　また、本明細書において、上記「ひも状の炭素系フィラー（Ｂ）の太さ（ｄ）の平均」の値は、実施例に記載の方法により測定した値を意味する。 In this specification, “the thickness (d) of the carbon-based filler (B) dispersed in a string” is perpendicular to the tangential direction at an arbitrary point of the string-like carbon-based filler (B). In the cut surface having the maximum area among the cut surfaces when cut, if the cut surface is a circle or an ellipse, it is a diameter or a major axis, and if the cut surface is a polygon, the side of the polygon This means the length of the longest side, specifically the length d in FIG.
Moreover, in this specification, the value of the above "average of the thickness (d) of a string-like carbon-type filler (B)" means the value measured by the method as described in an Example.
　なお、粘着剤層の形成過程において、原料として配合する炭素系フィラー（ｂ）同士が接触し、凝集することで、粘着剤層中でひも状に分散している炭素系フィラー（Ｂ）の太さは、上記範囲内となると考えられる。
　そのため、通常、ひも状に分散している炭素系フィラー（Ｂ）の太さ（ｄ）の平均値は、粘着性組成物の調製に用いる原料である炭素系フィラーの短径（Ｌ）の平均値よりも大きい値となる。 In the process of forming the pressure-sensitive adhesive layer, the carbon-based fillers (B) blended as raw materials come into contact with each other and aggregate to form a thick carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer. This is considered to be within the above range.
Therefore, the average value of the thickness (d) of the carbon-based filler (B) dispersed in a string is usually the average of the short diameter (L) of the carbon-based filler that is a raw material used for preparing the adhesive composition. The value is larger than the value.
　本発明の一態様において、粘着剤層中でひも状に分散している炭素系フィラー（Ｂ）の平均アスペクト比は、好ましくは３．０以上、より好ましくは５．０以上、更に好ましくは７．０以上、より更に好ましくは１５．０以上である。
　ひも状に分散している炭素系フィラー（Ｂ）の平均アスペクト比が３．０以上であれば、ひも状に分散している炭素系フィラー（Ｂ）同士が互いに接触し易く、網目状のネットワークの形成が容易となり、貼付表面上の炭素系フィラー（Ｂ）の占有面積率の値も増加する。その結果、導電性粘着シートの表面抵抗率を効果的に低下させることができる。
　なお、本発明の一態様において、ひも状の炭素系フィラー（Ｂ）の平均アスペクト比の上限としては、特に制限は無いが、通常１００００以下、好ましくは５０００以下である。 In one embodiment of the present invention, the average aspect ratio of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is preferably 3.0 or more, more preferably 5.0 or more, and even more preferably 7 0.0 or more, more preferably 15.0 or more.
If the average aspect ratio of the carbon-based fillers (B) dispersed in a string is 3.0 or more, the carbon-based fillers (B) dispersed in a string are easily in contact with each other, and a network network Of the carbon-based filler (B) on the pasting surface increases. As a result, the surface resistivity of the conductive adhesive sheet can be effectively reduced.
In the embodiment of the present invention, the upper limit of the average aspect ratio of the string-like carbon-based filler (B) is not particularly limited, but is usually 10,000 or less, preferably 5000 or less.
　本明細書において、「ひも状に分散している炭素系フィラー（Ｂ）のアスペクト比」とは、ひも状の炭素系フィラー（Ｂ）の太さ（ｄ）（図３のｄの長さ）に対する、ひも状の炭素系フィラー（Ｂ）の長さ（ｘ）（図３のｘの長さ）の割合、つまり「長さ（ｘ）／太さ（ｄ）」により算出される値である。
　また、本明細書において、上記「ひも状に分散している炭素系フィラー（Ｂ）の平均アスペクト比」の値は、実施例に記載の方法により測定した値を意味する。 In this specification, “the aspect ratio of the carbon-based filler (B) dispersed in a string” means the thickness (d) of the string-shaped carbon-based filler (B) (the length of d in FIG. 3). Is a value calculated by the ratio of the length (x) of the string-like carbon-based filler (B) (the length of x in FIG. 3), that is, “length (x) / thickness (d)”. .
In the present specification, the value of the “average aspect ratio of the carbon-based filler (B) dispersed in a string” means a value measured by the method described in Examples.
　「ひも状の炭素系フィラー（Ｂ）の長さ（ｘ）」とは、対象となる炭素系フィラーの太さ（ｄ）を有する部分において、最も離れた２点間の距離を指し、例えば、図３（ａ）、（ｂ）、（ｃ）に示すひも状の炭素系フィラー（Ｂ）１５、１５１、１５２においては、ｘで示される長さを指す。 “Length (x) of string-like carbon-based filler (B)” refers to the distance between the two most distant points in the portion having the thickness (d) of the target carbon-based filler, In the string-like carbon fillers (B) 15, 151, 152 shown in FIGS. 3A, 3B, 3C, the length indicated by x is indicated.
　なお、実施例に記載の方法にて粘着剤層中に分散している炭素系フィラー（Ｂ）を観察した際、対象となる炭素系フィラー（Ｂ）の一部分が、他の炭素系フィラー（Ｂ）と接触して形状の判断が難しい場合には、炭素系フィラー（Ｂ）のうち、少なくとも太さ（ｄ）の測定が可能な「ひも形状部分」のみに着目してもよい。
　つまり、当該ひも形状部分の長さ（ｘ’）を、「ひも状の炭素系フィラー（Ｂ）の長さ（ｘ）」と同様にして測定し、当該ひも形状部分のアスペクト比〔（ｘ’）／（ｄ）〕が３．０以上（好ましくは５．０以上、より好ましくは７．０以上、更に好ましくは１５．０以上）であることが確認されれば、対象となる炭素系フィラー（Ｂ）は、ひも状に分散している炭素系フィラー（Ｂ）と判断することができる。
　このようなひも形状部分を有する炭素系フィラー（Ｂ）も、網目状のネットワークの形成に寄与し、貼付表面上の炭素系フィラー（Ｂ）の占有面積率の値を増加させる因子となり得る。 In addition, when observing the carbon-type filler (B) currently disperse | distributed in an adhesive layer by the method as described in an Example, some carbon-type fillers (B) used as another carbon-type filler (B ), It may be difficult to determine the shape of the carbon-based filler (B), and only the “string-shaped portion” capable of measuring at least the thickness (d) may be noted.
That is, the length (x ′) of the string-shaped portion is measured in the same manner as the “length (x) of the string-like carbon-based filler (B)”, and the aspect ratio [(x ′ ) / (D)] is 3.0 or more (preferably 5.0 or more, more preferably 7.0 or more, and still more preferably 15.0 or more), the target carbon-based filler (B) can be judged as a carbon-based filler (B) dispersed in a string shape.
The carbon-based filler (B) having such a string-shaped portion also contributes to the formation of a network-like network, and can be a factor that increases the value of the occupied area ratio of the carbon-based filler (B) on the pasting surface.
　また、本発明の一態様において、導電性粘着シートの表面抵抗率をより低下させ、帯電防止性及び導電性に優れた導電性粘着シートとする観点から、当該導電性粘着シートの粘着剤層の貼付表面を平面視した際に、貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）が占める全占有面積（１００％）に対する、炭素系フィラー（Ｂ）が凝集してなる短径４μｍ以上の非ひも状凝集体の含有率が、好ましくは５０％以下、より好ましくは２０％以下、より好ましくは１０％以下、更に好ましくは５％以下、より更に好ましくは２％以下である。 Moreover, in one aspect of the present invention, from the viewpoint of further reducing the surface resistivity of the conductive pressure-sensitive adhesive sheet and making the conductive pressure-sensitive adhesive sheet excellent in antistatic properties and conductivity, the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet A short diameter formed by agglomeration of the carbon-based filler (B) with respect to the total occupied area (100%) occupied by the carbon-based filler (B) in an arbitrarily selected region on the pasting surface when the pasting surface is viewed in plan. The content of non-string aggregates of 4 μm or more is preferably 50% or less, more preferably 20% or less, more preferably 10% or less, still more preferably 5% or less, and still more preferably 2% or less.
　上記の「非ひも状凝集体」とは、炭素系フィラー（Ｂ）が凝集してなる短径４μｍ以上の凝集体であって、図４（ａ）に示すような、上述のひも状の炭素系フィラー（Ｂ）と接触せずに、独立して存在する凝集体２１を意味し、より具体的には、実施例に記載の方法にて、太さ（ｄ）の測定が可能であり、上述のアスペクト比が３．０以上のひも形状部分を有さない凝集体を指す。
　図４（ａ）の凝集体２１のような非ひも状凝集体は、炭素系フィラー（Ｂ）による網目状のネットワークを形成するものではない。また、それだけでなく、当該非ひも状凝集体の存在は、ひも状に分散している炭素系フィラー（Ｂ）の網目状のネットワークの形成を妨害する因子とも考えられる。
　そのため、当該非ひも状凝集体の含有量は、出来る限り少なくすることが好ましい。 The “non-string-like aggregate” is an aggregate having a short diameter of 4 μm or more formed by agglomeration of the carbon filler (B), and the above-mentioned string-like carbon as shown in FIG. Meaning the aggregate 21 that exists independently without contacting with the system filler (B), more specifically, the thickness (d) can be measured by the method described in the Examples, The aggregate which does not have a string-shaped part whose above-mentioned aspect ratio is 3.0 or more is pointed out.
A non-string-like aggregate such as the aggregate 21 in FIG. 4A does not form a network network by the carbon-based filler (B). In addition, the presence of the non-string aggregate is also considered to be a factor that hinders the formation of a network network of the carbon-based filler (B) dispersed in a string.
Therefore, it is preferable to reduce the content of the non-string aggregates as much as possible.
　一方、例えば、図４（ｂ）に示すような４個のひも形状部分１５ａ、１５ｂ、１５ｃ、１５ｄを有する凝集体２２について考える。凝集体２２が接触している４個のひも形状部分１５ａ、１５ｂ、１５ｃ、１５ｄのうち少なくとも１個のひも状部分のアスペクト比〔（ｘ’）／（ｄ）〕が３．０以上（好ましくは５．０以上、より好ましくは７．０以上、更に好ましくは１５．０以上）であることが確認されれば、この凝集体２２は、上述の「非ひも状凝集体」には該当しない。
　つまり、アスペクト比が３．０以上のひも形状部分を有する凝集体２２は、当該ひも形状部分が、網目状のネットワークの形成に寄与し、貼付表面上の炭素系フィラー（Ｂ）の占有面積率の値を増加させる因子となり得るともいえるためである。 On the other hand, for example, consider an aggregate 22 having four string-shaped portions 15a, 15b, 15c, and 15d as shown in FIG. The aspect ratio [(x ′) / (d)] of at least one of the four string-shaped portions 15a, 15b, 15c, and 15d in contact with the aggregate 22 is 3.0 or more (preferably Is not less than 5.0, more preferably not less than 7.0, and still more preferably not less than 15.0, the aggregate 22 does not fall under the above-mentioned “non-string-like aggregate”. .
That is, in the aggregate 22 having a string-shaped portion with an aspect ratio of 3.0 or more, the string-shaped portion contributes to the formation of a network network, and the occupied area ratio of the carbon-based filler (B) on the pasting surface This can be said to be a factor that increases the value of.
　なお、「ひも形状部分の太さ（ｄ）」は、上述の「ひも状に分散している炭素系フィラー（Ｂ）の太さ（ｄ）」と同様の方法により測定された長さである。
　また、「ひも形状部分の長さ（ｘ’）」とは、測定可能なひも形状部分の太さ（ｄ）を有する部分において、最も離れた２点間の距離を指し、例えば、図４（ｂ）に示すひも形状部分１５ａにおいては、ｘ’で示される長さを指す。 The “thickness of the string-shaped portion (d)” is a length measured by the same method as the above-described “thickness (d) of the carbon-based filler (B) dispersed in a string”. .
The “string-shaped portion length (x ′)” refers to the distance between the two most distant points in the portion having the measurable string-shaped portion thickness (d). For example, FIG. The string-shaped portion 15a shown in b) indicates the length indicated by x ′.
　本発明の一態様の導電性粘着シートの粘着剤層の厚さは、導電性粘着シートの用途に応じて適宜調整されるが、好ましくは１～１２００μｍ、より好ましくは２～６００μｍ、より好ましくは３～３００μｍ、更に好ましくは５～２５０μｍ、更に好ましくは１０～２００μｍ、より更に好ましくは１５～１５０μｍである。
　粘着剤層の厚さが１μｍ以上であれば、被着体の種類に依らずに、良好な粘着力を発現させることができる。一方、粘着剤層の厚さが１２００μｍ以下であれば、得られる導電性粘着シートの導電性が良好となる。また、当該導電性粘着シートを巻回体とした際に、粘着剤層が変形することによる巻きズレや、粘着剤層の端部からのはみ出しを抑制することができる。 The thickness of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is appropriately adjusted according to the use of the conductive pressure-sensitive adhesive sheet, but is preferably 1 to 1200 μm, more preferably 2 to 600 μm, and more preferably It is 3 to 300 μm, more preferably 5 to 250 μm, still more preferably 10 to 200 μm, and still more preferably 15 to 150 μm.
When the thickness of the pressure-sensitive adhesive layer is 1 μm or more, good adhesive force can be expressed regardless of the type of adherend. On the other hand, if the thickness of the pressure-sensitive adhesive layer is 1200 μm or less, the resulting conductive pressure-sensitive adhesive sheet has good conductivity. Moreover, when the said electroconductive adhesive sheet is used as a wound body, the winding shift by the adhesive layer deform | transforming and the protrusion from the edge part of an adhesive layer can be suppressed.
　本発明の導電性粘着シートにおいて、粘着剤層中の炭素系フィラー（Ｂ）の含有量は、当該粘着剤層の全質量（１００質量％）に対して、０．０１～２０質量％であり、好ましくは０．０５～１０質量％、より好ましくは０．１～７質量％、更に好ましくは０．２～５質量％、より更に好ましくは０．３～３．５質量％である。
　炭素系フィラー（Ｂ）の含有量が０．０１質量％未満であると、貼付表面上の炭素系フィラー（Ｂ）の占有面積率を高くすることが難しく、得られる導電性粘着シートの表面抵抗率を低くすることが困難となる。
　一方、炭素系フィラー（Ｂ）の含有量が２０質量％を超えると、十分な粘着力を有する導電性粘着シートを得ることが難しい。また、含有量を高くしても、得られる導電性粘着シートの表面抵抗率はあまり低下しない。一般的に導電性を良好とするためには、導電性の炭素系フィラー（Ｂ）の含有量を高くすることが通常行われる。しかしながら、単に含有量を大きくするだけでは、前述の非ひも状凝集体が多く形成されて炭素系フィラー（Ｂ）の網目状のネットワークの形成を妨害してしまうため、占有面積率を高く調整することが難しくなり、結果的に表面抵抗率を低くすることが困難となると考えられる。 In the conductive pressure-sensitive adhesive sheet of the present invention, the content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.01 to 20% by mass with respect to the total mass (100% by mass) of the pressure-sensitive adhesive layer. It is preferably 0.05 to 10% by mass, more preferably 0.1 to 7% by mass, still more preferably 0.2 to 5% by mass, and still more preferably 0.3 to 3.5% by mass.
When the content of the carbon-based filler (B) is less than 0.01% by mass, it is difficult to increase the occupied area ratio of the carbon-based filler (B) on the pasting surface, and the surface resistance of the obtained conductive adhesive sheet It becomes difficult to lower the rate.
On the other hand, when the content of the carbon-based filler (B) exceeds 20% by mass, it is difficult to obtain a conductive adhesive sheet having sufficient adhesive force. Moreover, even if content is made high, the surface resistivity of the electroconductive adhesive sheet obtained does not fall so much. In general, in order to improve the electrical conductivity, the content of the conductive carbon-based filler (B) is usually increased. However, if the content is simply increased, a large amount of the above-mentioned non-string aggregates are formed and hinder the formation of a network network of the carbon-based filler (B). It becomes difficult to lower the surface resistivity as a result.
　また、本発明の一態様の導電性粘着シートにおいて、粘着剤層中の粘着性樹脂（Ａ）の含有量は、当該粘着剤層の全質量（１００質量％）に対して、好ましくは３０～９９．９質量％、より好ましくは３５～９９質量％、更に好ましくは４０～９８質量％、より更に好ましくは４５～９７質量％である。 In the conductive adhesive sheet of one embodiment of the present invention, the content of the adhesive resin (A) in the adhesive layer is preferably from 30 to the total mass (100% by mass) of the adhesive layer. It is 99.9% by mass, more preferably 35 to 99% by mass, still more preferably 40 to 98% by mass, and still more preferably 45 to 97% by mass.
　なお、本発明において、「粘着剤層の全質量に対する粘着性樹脂（Ａ）又は炭素系フィラー（Ｂ）の含有量」は、「当該粘着剤層の形成材料である粘着性組成物中の有効成分（固形分）の全量（１００質量％）に対する粘着性樹脂（Ａ）又は炭素系フィラー（Ｂ）の配合量」とみなすこともできる。
　上述の「粘着性組成物中の有効成分」とは、粘着性組成物中に含まれる水や有機溶媒等の溶媒を除いた成分を意味する。 In the present invention, “the content of the adhesive resin (A) or the carbon-based filler (B) with respect to the total mass of the adhesive layer” is “effective in the adhesive composition that is a material for forming the adhesive layer. It can also be regarded as “the blending amount of the adhesive resin (A) or the carbon-based filler (B) relative to the total amount (100% by mass) of the component (solid content)”.
The above-mentioned “active ingredient in the adhesive composition” means an ingredient excluding a solvent such as water or an organic solvent contained in the adhesive composition.
〔粘着性組成物〕
　本発明の一態様の導電性粘着シートが有する粘着剤層は、粘着性樹脂（Ａ）及び炭素系フィラー（ｂ）を含む粘着性組成物から形成されることが好ましい。
　なお、上述のとおり、「炭素系フィラー（ｂ）」とは、粘着剤層を形成する前の粘着性組成物中に分散している炭素系フィラーを指す。
　当該粘着性組成物は、粘着性樹脂（Ａ）の種類に応じて、さらに粘着付与剤、架橋剤、触媒、架橋促進剤等の汎用添加剤を含有してもよい。
　以下、粘着剤層の形成材料である当該粘着性組成物に含まれる各成分について説明する。 [Adhesive composition]
It is preferable that the adhesive layer which the electroconductive adhesive sheet of 1 aspect of this invention has is formed from the adhesive composition containing adhesive resin (A) and a carbonaceous filler (b).
In addition, as above-mentioned, a "carbon-type filler (b)" points out the carbon-type filler currently disperse | distributing in the adhesive composition before forming an adhesive layer.
The said adhesive composition may contain general purpose additives, such as a tackifier, a crosslinking agent, a catalyst, a crosslinking accelerator, according to the kind of adhesive resin (A).
Hereinafter, each component contained in the said adhesive composition which is a forming material of an adhesive layer is demonstrated.
＜粘着性樹脂（Ａ）＞
　本発明において、粘着性樹脂（Ａ）は、当該樹脂単独で粘着性を有し、質量平均分子量（Ｍｗ）が１万以上の樹脂を意味する。
　粘着性樹脂（Ａ）の質量平均分子量（Ｍｗ）としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、好ましくは１万～２００万、より好ましくは２万～１５０万、更に好ましくは３万～１００万である。 <Adhesive resin (A)>
In the present invention, the adhesive resin (A) means a resin having adhesiveness by itself and having a mass average molecular weight (Mw) of 10,000 or more.
The mass average molecular weight (Mw) of the pressure-sensitive adhesive resin (A) is preferably from the viewpoint of forming a pressure-sensitive adhesive composition that easily forms a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface. It is 10,000 to 2,000,000, more preferably 20,000 to 1,500,000, still more preferably 30,000 to 1,000,000.
　粘着性組成物中の粘着性樹脂（Ａ）の含有量は、当該粘着性組成物中の有効成分（固形分）の全量（１００質量％）に対して、好ましくは３０～９９．９質量％、より好ましくは３５～９９質量％、更に好ましくは４０～９８質量％、より更に好ましくは４５～９７質量％である。 The content of the adhesive resin (A) in the adhesive composition is preferably 30 to 99.9% by mass with respect to the total amount (100% by mass) of the active ingredient (solid content) in the adhesive composition. More preferably, it is 35 to 99% by mass, still more preferably 40 to 98% by mass, and still more preferably 45 to 97% by mass.
　本発明の一態様で用いる粘着性樹脂（Ａ）としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物となり得る粘着性樹脂であれば特に制限は無く、例えば、アクリル系樹脂、ウレタン系樹脂、ポリイソブチレン系樹脂、ポリエステル系樹脂、及びポリオレフィン系樹脂等が挙げられる。
　これらの粘着性樹脂は、単独で又は２種以上を併用してもよい。 The adhesive resin (A) used in one embodiment of the present invention may be an adhesive resin that can form an adhesive composition that easily forms an adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface. There is no particular limitation, and examples thereof include acrylic resins, urethane resins, polyisobutylene resins, polyester resins, and polyolefin resins.
These adhesive resins may be used alone or in combination of two or more.
　これらの中でも、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、本発明の一態様で用いる粘着性樹脂（Ａ）としては、アクリル系樹脂及びウレタン系樹脂から選ばれる１種以上の粘着性樹脂を含むことが好ましく、アクリル系樹脂及びシリル基含有ウレタン系樹脂から選ばれる１種以上の粘着性樹脂を含むことがより好ましく、シリル基含有ウレタン系樹脂を含むことが更に好ましい。 Among these, as a pressure-sensitive adhesive composition (A) used in one embodiment of the present invention, from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface. Preferably contains at least one adhesive resin selected from acrylic resins and urethane resins, and more preferably contains at least one adhesive resin selected from acrylic resins and silyl group-containing urethane resins. Preferably, it contains a silyl group-containing urethane resin.
（アクリル系樹脂）
　本発明の一態様で用いるアクリル系樹脂としては、例えば、直鎖、分岐鎖のアルキル基を有するアルキル（メタ）アクリレートに由来する構成単位を含む重合体、環状構造を有する（メタ）アクリレートに由来する構成単位を含む重合体等が挙げられる。
　また、これらの重合体が共重合体である場合、共重合の形態としては、特に限定されず、当該アクリル系共重合体としては、ブロック共重合体、ランダム共重合体、グラフト共重合体のいずれであってもよい。 (Acrylic resin)
As an acrylic resin used in one embodiment of the present invention, for example, a polymer including a structural unit derived from an alkyl (meth) acrylate having a linear or branched alkyl group, or derived from a (meth) acrylate having a cyclic structure And a polymer containing the structural unit.
Further, when these polymers are copolymers, the form of copolymerization is not particularly limited, and examples of the acrylic copolymer include block copolymers, random copolymers, and graft copolymers. Either may be sufficient.
　アクリル系樹脂の質量平均分子量（Ｍｗ）としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、好ましくは１０万～１５０万、より好ましくは２０万～１３０万、更に好ましくは３５万～１１０万、より更に好ましくは５０万～９０万である。 The weight average molecular weight (Mw) of the acrylic resin is preferably 100,000 to from the viewpoint of easily forming an adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface. It is 1.5 million, more preferably 200,000 to 1.3 million, still more preferably 350,000 to 1.1 million, and still more preferably 500,000 to 900,000.
　これらの中でも、本発明の一態様で用いるアクリル系樹脂としては、炭素数１～２０のアルキル基を有するアルキル（メタ）アクリレート（ａ１’）（以下、「モノマー（ａ１’）」ともいう）に由来する構成単位（ａ１）、及び官能基含有モノマー（ａ２’）（以下、「モノマー（ａ２’）」ともいう）に由来する構成単位（ａ２）を含むアクリル系共重合体が好ましい。
　なお、当該アクリル系共重合体は、モノマー（ａ１’）（ａ２’）以外のその他のモノマー（ａ３’）に由来する構成単位（ａ３）を含んでいてもよい。 Among these, the acrylic resin used in one embodiment of the present invention includes an alkyl (meth) acrylate (a1 ′) having an alkyl group having 1 to 20 carbon atoms (hereinafter also referred to as “monomer (a1 ′)”). An acrylic copolymer containing the structural unit (a2) derived from the structural unit (a1) derived from and the functional group-containing monomer (a2 ′) (hereinafter also referred to as “monomer (a2 ′)”) is preferable.
In addition, the said acrylic copolymer may contain the structural unit (a3) derived from other monomers (a3 ') other than a monomer (a1') (a2 ').
　モノマー（ａ１’）が有するアルキル基の炭素数としては、粘着特性の向上の観点から、好ましくは１～１２、より好ましくは４～８、更に好ましくは４～６である。
　モノマー（ａ１’）としては、例えば、メチル（メタ）アクリレート、エチル（メタ）アクリレート、プロピル（メタ）アクリレート、ブチル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、ラウリル（メタ）アクリレート、トリデシル（メタ）アクリレート、ステアリル（メタ）アクリレート等が挙げられる。
　これらのモノマー（ａ１’）の中でも、ブチル（メタ）アクリレート及び２－エチルヘキシル（メタ）アクリレートが好ましく、ブチル（メタ）アクリレートがより好ましい。 The number of carbon atoms of the alkyl group contained in the monomer (a1 ′) is preferably 1 to 12, more preferably 4 to 8, and further preferably 4 to 6, from the viewpoint of improving the adhesive property.
Examples of the monomer (a1 ′) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tridecyl ( Examples include meth) acrylate and stearyl (meth) acrylate.
Among these monomers (a1 ′), butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate are preferable, and butyl (meth) acrylate is more preferable.
　構成単位（ａ１）の含有量は、上記アクリル系共重合体の全構成単位（１００質量％）に対して、好ましくは５０～９９．５質量％、より好ましくは６０～９９質量％、更に好ましくは７０～９７質量％、より更に好ましくは８０～９５質量％である。 The content of the structural unit (a1) is preferably 50 to 99.5% by mass, more preferably 60 to 99% by mass, and still more preferably based on all the structural units (100% by mass) of the acrylic copolymer. Is 70 to 97% by mass, more preferably 80 to 95% by mass.
　モノマー（ａ２’）としては、例えば、ヒドロキシ基含有モノマー、カルボキシ基含有モノマー、エポキシ基含有モノマー、アミノ基含有物モノマー、シアノ基含有モノマー、ケト基含有モノマー、アルコキシシリル基含有モノマー等が挙げられる。
　これらのモノマー（ａ２’）の中でも、カルボキシ基含有モノマーが好ましい。
　カルボキシ基含有モノマーとしては、（メタ）アクリル酸、マレイン酸、フマル酸、イタコン酸等が挙げられ、（メタ）アクリル酸が好ましい。 Examples of the monomer (a2 ′) include a hydroxy group-containing monomer, a carboxy group-containing monomer, an epoxy group-containing monomer, an amino group-containing monomer, a cyano group-containing monomer, a keto group-containing monomer, and an alkoxysilyl group-containing monomer. .
Among these monomers (a2 ′), a carboxy group-containing monomer is preferable.
Examples of the carboxy group-containing monomer include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, and (meth) acrylic acid is preferred.
　構成単位（ａ２）の含有量は、上記アクリル系共重合体の全構成単位（１００質量％）に対して、好ましくは０．５～５０質量％、より好ましくは１～４０質量％、更に好ましくは５～３０質量％、より更に好ましくは７～２０質量％である。 The content of the structural unit (a2) is preferably 0.5 to 50% by weight, more preferably 1 to 40% by weight, and still more preferably based on all the structural units (100% by weight) of the acrylic copolymer. Is 5 to 30% by mass, more preferably 7 to 20% by mass.
　モノマー（ａ３’）としては、例えば、シクロヘキシル（メタ）アクリレート、ベンジル（メタ）アクリレート、イソボルニル（メタ）アクリレート、ジシクロペンタニル（メタ）アクリレート、ジシクロペンテニル（メタ）アクリレート、ジシクロペンテニルオキシエチル（メタ）アクリレート、イミド（メタ）アクリレート等の環状構造を有する（メタ）アクリレート、酢酸ビニル、アクリロニトリル、スチレン等が挙げられる。 Examples of the monomer (a3 ′) include cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and dicyclopentenyloxyethyl. Examples include (meth) acrylates having a cyclic structure such as (meth) acrylates and imide (meth) acrylates, vinyl acetate, acrylonitrile, and styrene.
　構成単位（ａ３）の含有量は、アクリル系共重合体の全構成単位（１００質量％）に対して、好ましくは０～３０質量％、より好ましくは０～２０質量％、更に好ましくは０～１０質量％、より更に好ましくは０～５質量％である。 The content of the structural unit (a3) is preferably 0 to 30% by weight, more preferably 0 to 20% by weight, and still more preferably 0 to 0% with respect to all the structural units (100% by weight) of the acrylic copolymer. The amount is 10% by mass, more preferably 0 to 5% by mass.
　なお、上述のモノマー（ａ１’）～（ａ３’）は、単独で又は２種以上を組み合わせて用いてもよい。 The monomers (a1 ′) to (a3 ′) described above may be used alone or in combination of two or more.
（ウレタン系樹脂）
　本発明の一態様で用いるウレタン系樹脂としては、主鎖及び側鎖の少なくとも一方に、ウレタン結合及び尿素結合の１つ以上を有する重合体であれば、特に制限されない。
　具体的なウレタン系樹脂としては、例えば、ポリオールと多価イソシアネート化合物とを反応して得られるウレタン系プレポリマー（Ｕ１）や、当該ウレタン系プレポリマー（Ｕ１）に対して、更に鎖延長剤を用いた鎖延長反応を行い得られるウレタン系ポリマー（Ｕ２）等が挙げられる。 (Urethane resin)
The urethane resin used in one embodiment of the present invention is not particularly limited as long as it is a polymer having at least one of a urethane bond and a urea bond in at least one of a main chain and a side chain.
As a specific urethane-based resin, for example, a chain extender is further added to the urethane-based prepolymer (U1) obtained by reacting a polyol and a polyvalent isocyanate compound, or the urethane-based prepolymer (U1). Examples thereof include a urethane polymer (U2) obtained by performing the chain extension reaction used.
　ウレタン系樹脂の質量平均分子量（Ｍｗ）としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、好ましくは１万～２０万、より好ましくは１．２万～１５万、更に好ましくは１．５万～１０万、より更に好ましくは２万～７万である。 The mass average molecular weight (Mw) of the urethane-based resin is preferably 10,000 to 10,000 from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface. It is 200,000, more preferably 12,000 to 150,000, still more preferably 15,000 to 100,000, and still more preferably 20,000 to 70,000.
　ウレタン系プレポリマー（Ｕ１）の原料となるポリオールとしては、例えば、アルキレンジオール、ポリエーテル型ポリオール、ポリエステル型ポリオール、ポリカーボネート型ポリオール等のポリオール化合物が挙げられるが、ポリオールであれば特に限定はされず、２官能のジオール、３官能のトリオールであってもよい。
　これらのポリオールの中でも、入手の容易性、反応性等の観点から、ジオールが好ましい。 Examples of the polyol used as a raw material for the urethane-based prepolymer (U1) include polyol compounds such as alkylene diol, polyether-type polyol, polyester-type polyol, and polycarbonate-type polyol. It may be a bifunctional diol or a trifunctional triol.
Among these polyols, diols are preferable from the viewpoints of availability, reactivity, and the like.
　ジオールとしては、例えば、１，３－プロパンジオール、１，４－ブタンジオール、１，５－ペンタンジオール、ネオペンチルグリコール、１，６－ヘキサンジオール、１，７－ヘプタンジオール等のアルカンジオール、エチレングリコール、プロピレングリコール、ジエチレングリコール、ジプロピレングリコール等のアルキレングリコール、ポリエチレングリコール、ポリプロピレングリコール、ポリブチレングリコール等のポリアルキレングリコール、ポリテトラメチレングリコール等のポリオキシアルキレングリコール等が挙げられる。なお、これらのジオールは、単独で又は２種以上組み合わせて用いてもよい。
　これらのジオールの中でも、さらに鎖延長剤との反応を行う場合、当該反応においてゲル化を抑制する観点から、質量平均分子量１０００～３０００のグリコールが好ましい。 Examples of the diol include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, and ethylene. Examples thereof include alkylene glycols such as glycol, propylene glycol, diethylene glycol and dipropylene glycol, polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polybutylene glycol, and polyoxyalkylene glycols such as polytetramethylene glycol. In addition, you may use these diols individually or in combination of 2 or more types.
Among these diols, when a reaction with a chain extender is further performed, a glycol having a mass average molecular weight of 1000 to 3000 is preferable from the viewpoint of suppressing gelation in the reaction.
　ウレタン系プレポリマー（Ｕ１）の原料となる多価イソシアネート化合物としては、芳香族ポリイソシアネート、脂肪族ポリイソシアネート、脂環式ポリイソシアネート等が挙げられる。
　芳香族ポリイソシアネートとしては、例えば、１，３－フェニレンジイソシアネート、１，４－フェニレンジイソシアネート、４，４’－ジフェニルメタンジイソシアネート（ＭＤＩ）、２，４－トリレンジイソシアネート（２，４－ＴＤＩ）、２，６－トリレンジイソシアネート（２，６－ＴＤＩ）、４，４’－トルイジンジイソシアネート、２，４，６－トリイソシアネートトルエン、１，３，５－トリイソシアネートベンゼン、ジアニシジンジイソシアネート、４，４’－ジフェニルエーテルジイソシアネート、４，４’，４”－トリフェニルメタントリイソシアネート、１，４－テトラメチルキシリレンジイソシアネート、１，３－テトラメチルキシリレンジイソシアネート等が挙げられる。
　脂肪族ポリイソシアネートとしては、例えば、トリメチレンジイソシアネート、テトラメチレンジイソシアネート、ヘキサメチレンジイソシアネート（ＨＭＤＩ）、ペンタメチレンジイソシアネート、１，２－プロピレンジイソシアネート、２，３－ブチレンジイソシアネート、１，３－ブチレンジイソシアネート、ドデカメチレンジイソシアネート、２，４，４－トリメチルヘキサメチレンジイソシアネート等が挙げられる。
　脂環式ポリイソシアネートとしては、例えば、３－イソシアネートメチル－３，５，５－トリメチルシクロヘキシルイソシアネート（ＩＰＤＩ）、１，３－シクロペンタンジイソシアネート、１，３－シクロヘキサンジイソシアネート、１，４－シクロヘキサンジイソシアネート、メチル－２，４－シクロヘキサンジイソシアネート、メチル－２，６－シクロヘキサンジイソシアネート、４，４’－メチレンビス（シクロヘキシルイソシアネート）、１，４－ビス（イソシアネートメチル）シクロヘキサン、１，４－ビス（イソシアネートメチル）シクロヘキサン等が挙げられる。
　なお、これらの多価イソシアネート化合物は、上記ポリイソシアネートのトリメチロールプロパンアダクト型変性体、水と反応させたビュウレット型変性体、イソシアヌレート環を含有させたイソシアヌレート型変性体であってもよい。 Examples of the polyvalent isocyanate compound used as a raw material for the urethane prepolymer (U1) include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.
Examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2 , 6-Tolylene diisocyanate (2,6-TDI), 4,4′-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4 ′ -Diphenyl ether diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, 1,4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate and the like.
Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HMDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, and dodeca. Examples include methylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate.
Examples of the alicyclic polyisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, Methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, 1,4-bis (isocyanatemethyl) cyclohexane Etc.
In addition, these polyisocyanate compounds may be a trimethylolpropane adduct modified product of the above polyisocyanate, a burette modified product reacted with water, or an isocyanurate modified product containing an isocyanurate ring.
　これらの多価イソシアネート化合物の中でも、粘着物性に優れたウレタン系ポリマーを得る観点から、４，４’－ジフェニルメタンジイソシアネート（ＭＤＩ）、２，４－トリレンジイソシアネート（２，４－ＴＤＩ）、２，６－トリレンジイソシアネート（２，６－ＴＤＩ）、ヘキサメチレンジイソシアネート（ＨＭＤＩ）、３－イソシアネートメチル－３，５，５－トリメチルシクロヘキシルイソシアネート（ＩＰＤＩ）及びこれらの変性体から選ばれる１種以上が好ましく、耐候性の観点から、ＨＭＤＩ、ＩＰＤＩ及びこれらの変性体から選ばれる１種以上がより好ましい。 Among these polyvalent isocyanate compounds, 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2, from the viewpoint of obtaining a urethane polymer having excellent adhesive properties. One or more selected from 6-tolylene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI) and modified products thereof are preferable. From the viewpoint of weather resistance, at least one selected from HMDI, IPDI, and modified products thereof is more preferable.
　ウレタン系プレポリマー（Ｕ１）中のイソシアネート基含有量（ＮＣＯ％）は、ＪＩＳ　Ｋ　１６０３に準じて測定された値において、好ましくは０．５～１２質量％、より好ましくは１～４質量％である。 The isocyanate group content (NCO%) in the urethane-based prepolymer (U1) is preferably 0.5 to 12% by mass, more preferably 1 to 4% by mass, as measured according to JIS K 1603. is there.
　鎖延長剤としては、水酸基及びアミノ基の少なくとも一方を２つ有する化合物、又は、水酸基及びアミノ基の少なくとも一方を３つ以上有する化合物が好ましい。 As the chain extender, a compound having at least one of hydroxyl group and amino group, or a compound having at least three of hydroxyl group and amino group is preferable.
　水酸基及びアミノ基の少なくとも一方を２つ有する化合物としては、脂肪族ジオール、脂肪族ジアミン、アルカノールアミン、ビスフェノール、芳香族ジアミンからなる群より選ばれる少なくとも１種の化合物が好ましい。
　脂肪族ジオールとしては、例えば、１，３－プロパンジオール、１，４－ブタンジオール、１，５－ペンタンジオール、ネオペンチルグリコール、１，６－ヘキサンジオール、１，７－ヘプタンジオール等のアルカンジオール、エチレングリコール、プロピレングリコール、ジエチレングリコール、ジプロピレングリコール等のアルキレングリコールが挙げられる。
　脂肪族ジアミンとしては、例えば、エチレンジアミン、１，３－プロパンジアミン、１，４－ブタンジアミン、１，５－ペンタンジアミン、１，６－ヘキサンジアミン等が挙げられる。
　アルカノールアミンとしては、例えば、モノエタノールアミン、モノプロパノールアミン、イソプロパノールアミン等が挙げられる。
　ビスフェノールとしては、例えば、ビスフェノールＡ等が挙げられる。
　芳香族ジアミンとしては、例えば、ジフェニルメタンジアミン、トリレンジアミン、キシリレンジアミン等が挙げられる。 The compound having at least one of a hydroxyl group and an amino group is preferably at least one compound selected from the group consisting of aliphatic diols, aliphatic diamines, alkanolamines, bisphenols, and aromatic diamines.
Examples of the aliphatic diol include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and 1,7-heptanediol. And alkylene glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol.
Examples of the aliphatic diamine include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, and the like.
Examples of the alkanolamine include monoethanolamine, monopropanolamine, isopropanolamine and the like.
Examples of bisphenol include bisphenol A and the like.
Examples of the aromatic diamine include diphenylmethanediamine, tolylenediamine, xylylenediamine, and the like.
　水酸基及びアミノ基の少なくとも一方を３つ以上有する化合物としては、例えば、トリメチロールプロパン、ジトリメチロールプロパン、ペンタエリスリトール、ジペンタエリスリトール等のポリオール、１－アミノ－２，３－プロパンジオール、１－メチルアミノ－２，３－プロパンジオール、Ｎ－（２－ヒドロキシプロピルエタノールアミン）等のアミノアルコール、テトラメチルキシリレンジアミンのエチレンオキシド又はプロピレンオキシド付加物等が挙げられる。 Examples of the compound having at least three hydroxyl groups and amino groups include polyols such as trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, 1-amino-2,3-propanediol, and 1-methyl. Examples include amino alcohols such as amino-2,3-propanediol and N- (2-hydroxypropylethanolamine), and ethylene oxide or propylene oxide adducts of tetramethylxylylenediamine.
　本発明で粘着性樹脂（Ａ）として用いるウレタン形樹脂の中でも、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、シリル基含有ウレタン系樹脂が好ましい。
　シリル基含有ウレタン系樹脂としては、上述のウレタン系樹脂の主鎖及び側鎖の少なく一方の末端に下記一般式（１）で表される加水分解性シリル基を有する重合体であることが好ましく、上述のウレタン系樹脂の主鎖の両末端に下記一般式（１）で表される加水分解性シリル基を有する重合体であることがより好ましい。 Among the urethane-type resins used as the adhesive resin (A) in the present invention, from the viewpoint of forming an adhesive composition that easily forms an adhesive layer having a high occupation area ratio of the carbon-based filler (B) on the pasting surface, silyl A group-containing urethane resin is preferred.
The silyl group-containing urethane resin is preferably a polymer having a hydrolyzable silyl group represented by the following general formula (1) at least one of the main chain and side chain of the above urethane resin. More preferably, the polymer has a hydrolyzable silyl group represented by the following general formula (1) at both ends of the main chain of the urethane resin.
Figure JPOXMLDOC01-appb-C000001
Figure JPOXMLDOC01-appb-C000001
　上記一般式（１）中、Ｘ１、Ｘ２は、それぞれ独立に、ヒドロキシ基又は置換もしくは無置換のアルコキシ基を示し、Ｒ１は、置換もしくは無置換の炭素数１～２０のアルキル基を示す。
　上記一般式（１）中のＸ１、Ｘ２がアルコキシ基である場合の当該アルコキシ基の炭素数は、加水分解脱水縮合の反応性の観点から、好ましくは１～１２、より好ましくは１～６、更に好ましくは１～３、より更に好ましくは１～２である。
　また、一般式（１）中、Ｒ１で示されるアルキル基の炭素数は、加水分解脱水縮合の反応性の観点から、好ましくは１～１２、より好ましくは１～６、更に好ましくは１～３、より更に好ましくは１～２である。
　Ｘ１、Ｘ２、Ｒ１が置換基を有する場合の置換基としては、例えば、ハロゲン原子（フッ素原子、塩素原子、臭素原子、ヨウ素原子）、ヒドロキシル基、シアノ基、ニトロ基及びアミノ基等が挙げられる。 In the general formula (1), X 1 and X 2 each independently represent a hydroxy group or a substituted or unsubstituted alkoxy group, and R 1 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Show.
When X 1 and X 2 in the general formula (1) are alkoxy groups, the number of carbon atoms of the alkoxy group is preferably 1 to 12, more preferably 1 to 1, from the viewpoint of hydrolytic dehydration condensation reactivity. 6, more preferably 1 to 3, and still more preferably 1 to 2.
In general formula (1), the number of carbon atoms of the alkyl group represented by R 1 is preferably 1 to 12, more preferably 1 to 6, and still more preferably 1 to 1, from the viewpoint of the hydrolytic dehydration condensation reactivity. 3, more preferably 1 to 2.
Examples of the substituent when X 1 , X 2 , and R 1 have a substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), a hydroxyl group, a cyano group, a nitro group, and an amino group. Is mentioned.
　本発明の一態様で用いるシリル基含有ウレタン系樹脂の主鎖又は側鎖の末端部分の具体的な構造としては、下記一般式（２）～（８）（末端部分－Ａ～Ｇ）に表される構造であることが好ましく、下記一般式（２）で表される構造を有することがより好ましい。 The specific structure of the terminal part of the main chain or side chain of the silyl group-containing urethane resin used in one embodiment of the present invention is represented by the following general formulas (2) to (8) (terminal parts -A to G). It is preferable that it has a structure represented by the following general formula (2).
Figure JPOXMLDOC01-appb-C000002
Figure JPOXMLDOC01-appb-C000002
Figure JPOXMLDOC01-appb-C000003
Figure JPOXMLDOC01-appb-C000003
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000005
Figure JPOXMLDOC01-appb-C000005
Figure JPOXMLDOC01-appb-C000006
Figure JPOXMLDOC01-appb-C000006
Figure JPOXMLDOC01-appb-C000007
Figure JPOXMLDOC01-appb-C000007
Figure JPOXMLDOC01-appb-C000008
Figure JPOXMLDOC01-appb-C000008
　上記一般式（２）～（８）中、Ｘ１、Ｘ２及びＲ１は上記一般式（１）と同様である。
　Ｒ２及びＲ３は、それぞれ独立に、置換もしくは無置換の炭素数１～２０のアルキル基を示し、当該アルキル基の炭素数としては、好ましくは１～１２、より好ましくは１～８、更に好ましくは１～６、より更に好ましくは１～３である。
　また、上記一般式（８）中、Ａはアルキレン基を示し、当該アルキレン基の炭素数は、好ましくは１～２０、より好ましくは１～１２、更に好ましくは１～６である。
　一方、上記一般式（８）中、Ｂは炭素数１～２０の有機基を示す。当該有機基としては、例えば、置換もしくは置換基の炭素数１～２０のアルキル基、置換もしくは置換基の炭素数１～２０のアルキルアミノ基、置換もしくは置換基の炭素数６～２０のアリールアミノ基、置換もしくは置換基の炭素数１～２０のアルコキシ基、置換もしくは置換基の炭素数６～２０のアリールオキシ基、置換もしくは置換基の炭素数６～２０の芳香族炭化水素基、置換もしくは置換基の炭素数２～２０の複素環基、置換もしくは置換基の炭素数２～２０のアルケニル基、置換もしくは置換基の炭素数２～２０のアルキニル基、置換もしくは置換基の炭素数３～２０のシクロアルキル基等が挙げられる。
　なお、上記一般式（２）～（８）中のＲ２、Ｒ３、Ａ、Ｂが置換基を有している場合、当該置換基としては、例えば、ハロゲン原子（フッ素原子、塩素原子、臭素原子、ヨウ素原子）、シアノ基、及びニトロ基等が挙げられる。 In the general formulas (2) to (8), X 1 , X 2 and R 1 are the same as those in the general formula (1).
R 2 and R 3 each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and the alkyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, Preferably it is 1-6, and more preferably 1-3.
In the general formula (8), A represents an alkylene group, and the alkylene group preferably has 1 to 20, more preferably 1 to 12, and still more preferably 1 to 6.
On the other hand, in the general formula (8), B represents an organic group having 1 to 20 carbon atoms. Examples of the organic group include a substituted or substituted alkyl group having 1 to 20 carbon atoms, a substituted or substituted alkyl group having 1 to 20 carbon atoms, and a substituted or substituted aryl group having 6 to 20 carbon atoms. Group, substituted or substituted alkoxy group having 1 to 20 carbon atoms, substituted or substituted aryloxy group having 6 to 20 carbon atoms, substituted or substituted aromatic hydrocarbon group having 6 to 20 carbon atoms, substituted or substituted Substituent heterocyclic group having 2 to 20 carbon atoms, substituted or substituted alkenyl group having 2 to 20 carbon atoms, substituted or substituted alkynyl group having 2 to 20 carbon atoms, substituted or substituted carbon atom having 3 to 3 carbon atoms 20 cycloalkyl groups and the like.
When R 2 , R 3 , A, and B in the general formulas (2) to (8) have a substituent, examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, Bromine atom, iodine atom), cyano group, nitro group and the like.
　シリル基含有ウレタン系樹脂の主鎖及び側鎖の骨格としては、上述のウレタン系樹脂と同様であるが、得られる粘着性組成物に対して、適度な柔軟性を付与し、形成される粘着剤層中に炭素系フィラー（Ｂ）を均一に分散させ易くする観点から、主鎖としてポリオキシアルキレン骨格を有するシリル基含有ウレタン系ポリマーであることが好ましい。
　当該ポリオキシアルキレンとしては、上記観点から、ポリオキシプロピレン、ポリオキシエチレンが好ましく、ポリオキシプロピレンがより好ましい。
　なお、シリル基含有ウレタン系樹脂の質量平均分子量（Ｍｗ）の好適範囲は、上述のウレタン系樹脂の質量平均分子量（Ｍｗ）の好適範囲と同じである。 The skeleton of the main chain and side chain of the silyl group-containing urethane resin is the same as that of the above-mentioned urethane resin, but gives an appropriate flexibility to the obtained adhesive composition, and is formed From the viewpoint of facilitating uniform dispersion of the carbon-based filler (B) in the agent layer, a silyl group-containing urethane polymer having a polyoxyalkylene skeleton as the main chain is preferable.
As the polyoxyalkylene, polyoxypropylene and polyoxyethylene are preferable from the above viewpoint, and polyoxypropylene is more preferable.
In addition, the suitable range of the mass average molecular weight (Mw) of silyl group containing urethane type resin is the same as the suitable range of the above-mentioned mass average molecular weight (Mw) of urethane type resin.
（ポリイソブチレン系樹脂）
　本発明の一態様で用いるポリイソブチレン系樹脂（以下、「ＰＩＢ系樹脂」ともいう）は、主鎖及び側鎖の少なくとも一方にポリイソブチレン骨格を有する樹脂であれば、特に制限はされない。 (Polyisobutylene resin)
The polyisobutylene resin (hereinafter also referred to as “PIB resin”) used in one embodiment of the present invention is not particularly limited as long as it has a polyisobutylene skeleton in at least one of the main chain and the side chain.
　ＰＩＢ系樹脂の質量平均分子量（Ｍｗ）としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高い粘着剤層を形成し易い粘着性組成物とする観点から、好ましくは２万以上、より好ましくは３万～１００万、更に好ましくは５万～８０万、より更に好ましくは７万～６０万である。 The mass average molecular weight (Mw) of the PIB-based resin is preferably 20,000 or more from the viewpoint of easily forming a pressure-sensitive adhesive layer having a high occupied area ratio of the carbon-based filler (B) on the pasting surface. More preferably, it is 30,000 to 1,000,000, more preferably 50,000 to 800,000, and still more preferably 70,000 to 600,000.
　ＰＩＢ系樹脂としては、例えば、イソブチレンの単独重合体であるポリイソブチレン、イソブチレンとイソプレンの共重合体、イソブチレンとｎ－ブテンの共重合体、イソブチレンとブタジエンの共重合体、及びこれら共重合体を臭素化又は塩素化等したハロゲン化ブチルゴム等が挙げられる。 Examples of the PIB resin include polyisobutylene which is a homopolymer of isobutylene, a copolymer of isobutylene and isoprene, a copolymer of isobutylene and n-butene, a copolymer of isobutylene and butadiene, and these copolymers. Examples thereof include halogenated butyl rubber that has been brominated or chlorinated.
　なお、ＰＩＢ系樹脂が共重合体である場合、イソブチレンからなる構成単位が、全構成単位の中で一番多く含まれているものとする。
　イソブチレンからなる構成単位の含有量は、ＰＩＢ系樹脂の全構成単位（１００質量％）に対して、好ましくは８０～１００質量％、より好ましくは９０～１００質量％、更に好ましくは９５～１００質量％である。
　これらのＰＩＢ系樹脂は、単独又は２種以上を併用してもよい。 In addition, when a PIB resin is a copolymer, the structural unit which consists of isobutylene shall be contained most in all the structural units.
The content of the structural unit composed of isobutylene is preferably 80 to 100% by weight, more preferably 90 to 100% by weight, and still more preferably 95 to 100% by weight with respect to all the structural units (100% by weight) of the PIB resin. %.
These PIB resins may be used alone or in combination of two or more.
　また、ＰＩＢ系樹脂を用いる場合、質量平均分子量が高いＰＩＢ系樹脂と、質量平均分子量が低いＰＩＢ系樹脂とを併用することが好ましく、より具体的には、質量平均分子量が２７万～６０万のＰＩＢ系樹脂（ｐ１）（以下、「ＰＩＢ系樹脂（ｐ１）」ともいう）と、質量平均分子量が５万～２５万のＰＩＢ系樹脂（ｐ２）（以下、「ＰＩＢ系樹脂（ｐ２）」ともいう）とを併用することが好ましい。
　質量平均分子量の高いＰＩＢ系樹脂（ｐ１）を用いることで、得られる粘着性組成物から形成される粘着剤層の耐久性及び耐候性を向上させると共に、粘着力を向上させることもできる。
　また、質量平均分子量の低いＰＩＢ系樹脂（ｐ２）を用いることで、ＰＩＢ系樹脂（ｐ１）と良好に相溶して、適度にＰＩＢ系樹脂（ｐ１）を可塑化させることができ、粘着剤層の被着体に対する濡れ性を高め、粘着物性、柔軟性等を向上させることができる。 When using a PIB resin, it is preferable to use a PIB resin having a high mass average molecular weight in combination with a PIB resin having a low mass average molecular weight. More specifically, the mass average molecular weight is 270,000 to 600,000. PIB resin (p1) (hereinafter also referred to as “PIB resin (p1)”) and PIB resin (p2) having a mass average molecular weight of 50,000 to 250,000 (hereinafter referred to as “PIB resin (p2)”) Are also preferably used in combination.
By using the PIB resin (p1) having a high mass average molecular weight, it is possible to improve the durability and weather resistance of the pressure-sensitive adhesive layer formed from the obtained pressure-sensitive adhesive composition, and also improve the pressure-sensitive adhesive force.
Further, by using the PIB resin (p2) having a low mass average molecular weight, it can be well compatible with the PIB resin (p1), and the PIB resin (p1) can be appropriately plasticized. The wettability of the layer to the adherend can be increased, and the adhesive properties, flexibility, and the like can be improved.
　ＰＩＢ系樹脂（ｐ１）の質量平均分子量（Ｍｗ）は、好ましくは２７万～６０万、より好ましくは２９万～４８万、更に好ましくは３１万～４５万、より更に好ましくは３２万～４０万である。
　ＰＩＢ系樹脂（ｐ２）の質量平均分子量（Ｍｗ）は、好ましくは５万～２５万、より好ましくは８万～２３万、更に好ましくは１４万～２２万、より更に好ましくは１８万～２１万である。 The mass average molecular weight (Mw) of the PIB resin (p1) is preferably 270,000 to 600,000, more preferably 290,000 to 480,000, still more preferably 310,000 to 450,000, and even more preferably 320,000 to 400,000. It is.
The mass average molecular weight (Mw) of the PIB resin (p2) is preferably 50,000 to 250,000, more preferably 80,000 to 230,000, still more preferably 140,000 to 220,000, and still more preferably 180,000 to 210,000. It is.
　ＰＩＢ系樹脂（ｐ１）１００質量部に対する、ＰＩＢ系樹脂（ｐ２）の含有割合は、好ましくは５～５５質量部、より好ましくは６～４０質量部、更に好ましくは７～３０質量部、より更に好ましくは８～２０質量部である。 The content ratio of the PIB resin (p2) to 100 parts by mass of the PIB resin (p1) is preferably 5 to 55 parts by mass, more preferably 6 to 40 parts by mass, still more preferably 7 to 30 parts by mass, and even more. The amount is preferably 8 to 20 parts by mass.
（ポリエステル系樹脂）
　本発明の一態様で用いるポリエステル系樹脂は、酸成分とジオール成分又はポリオール成分とを重縮合反応により得られる共重合体であり、当該共重合体の変性物も含まれる。
　上記重縮合反応は、直接エステル化法、エステル交換法等の一般的なポリエステル化反応によって行われる。
　なお、当該ポリエステル系樹脂の共重合の形態は、特に限定されず、当該ポリエステル系樹脂としては、ブロック共重合体、ランダム共重合体、グラフト共重合体のいずれであってもよい。また、当該ポリエステル系樹脂は、単独又は２種以上を併用してもよい。 (Polyester resin)
The polyester resin used in one embodiment of the present invention is a copolymer obtained by a polycondensation reaction of an acid component and a diol component or a polyol component, and includes a modified product of the copolymer.
The polycondensation reaction is performed by a general polyesterification reaction such as a direct esterification method or a transesterification method.
The form of copolymerization of the polyester resin is not particularly limited, and the polyester resin may be any of a block copolymer, a random copolymer, and a graft copolymer. Moreover, the said polyester-type resin may use individually or in combination of 2 or more types.
　上記酸成分としては、例えば、テレフタル酸、イソフタル酸、無水フタル酸、α－ナフタレンジカルボン酸、５－ナトリウムスルホイソフタル酸、５－カリウムスルホイソフタル酸又はこれらのエステル類、ピメリン酸、スベリン酸、アゼライン酸、セバシン酸、ウンデシレン酸、ドデカンジカルボン酸又はこれらのエステル類等の脂肪族ジカルボン酸；１，４－シクロヘキサヒドロ無水フタル酸等の脂環式ジカルボン酸等が挙げられる。 Examples of the acid component include terephthalic acid, isophthalic acid, phthalic anhydride, α-naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid or esters thereof, pimelic acid, suberic acid, and azelain. Examples thereof include aliphatic dicarboxylic acids such as acid, sebacic acid, undecylenic acid, dodecanedicarboxylic acid or esters thereof; and alicyclic dicarboxylic acids such as 1,4-cyclohexahydrophthalic anhydride.
　上記ジオール成分又はポリオール成分としては、例えば、エチレングリコール、１，２－プロピレングリコール、１，３－プロピレングリコール、１，３－ブタンジオール、１，４－ブタンジオール、１，５－ペンタンジオール、１，６－ヘキサンジオール、１，８－オクタンジオール、１，９－ノナンジオール、ネオペンチルグリコール、３－メチルペンタンジオール、２，２，３－トリメチルペンタンジオール、ジエチレングリコール、トリエチレングリコール、ジプロピレングリコール等の脂肪族グリコール、１，４－シクロヘキサンジオール、１，４－シクロヘキサンジメタノール等の脂環式グリコール、ビスフェノールＡ等の芳香族グリコール等が挙げられる。 Examples of the diol component or polyol component include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, , 6-hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, etc. Alicyclic glycols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic glycols such as bisphenol A.
（ポリオレフィン系樹脂）
　本発明の一態様で用いるポリオレフィン系樹脂は、エチレン、プロピレン等のオレフィン化合物由来の構成単位を有する重合体であれば、特に制限はされない。
　なお、当該ポリオレフィン系樹脂が共重合体である場合、共重合の形態は、特に限定されず、当該ポリオレフィン系樹脂としては、ブロック共重合体、ランダム共重合体、グラフト共重合体のいずれであってもよい。当該ポリオレフィン系樹脂は、単独又は２種以上を併用してもよい。 (Polyolefin resin)
The polyolefin resin used in one embodiment of the present invention is not particularly limited as long as it is a polymer having a structural unit derived from an olefin compound such as ethylene or propylene.
When the polyolefin resin is a copolymer, the form of copolymerization is not particularly limited, and the polyolefin resin may be any of a block copolymer, a random copolymer, and a graft copolymer. May be. The polyolefin resin may be used alone or in combination of two or more.
　具体的なポリオレフィン系樹脂としては、例えば、低密度ポリエチレン、中密度ポリエチレン、高密度ポリエチレン、及び線状低密度ポリエチレン等のポリエチレン、ポリプロピレン、エチレンとプロピレンとの共重合体、エチレンと他のα－オレフィンとの共重合体、プロピレンと他のα－オレフィンとの共重合体、エチレンとプロピレンと他のα－オレフィンとの共重合体、エチレンと他のエチレン性不飽和単量体との共重合体（エチレン－酢酸ビニル共重合体、エチレン－アルキル（メタ）アクリレート共重合体等）等が挙げられる。 Specific polyolefin resins include, for example, polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene, polypropylene, copolymers of ethylene and propylene, ethylene and other α- Copolymers of olefins, copolymers of propylene and other α-olefins, copolymers of ethylene, propylene and other α-olefins, copolymers of ethylene and other ethylenically unsaturated monomers Examples thereof include ethylene (vinyl-vinyl acetate copolymer, ethylene-alkyl (meth) acrylate copolymer, etc.) and the like.
　上記のα－オレフィンとしては、例えば、１－ブテン、１－ペンテン、１－ヘキセン、１－ヘプテン、１－オクテン、４－メチル－１－ペンテン、４－メチル－１－ヘキセン等が挙げられる。
　上記のエチレン性不飽和単量体としては、例えば、酢酸ビニル、（メタ）アクリル酸、アルキル（メタ）アクリレート、ビニルアルコール等が挙げられる。 Examples of the α-olefin include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 4-methyl-1-hexene and the like.
Examples of the ethylenically unsaturated monomer include vinyl acetate, (meth) acrylic acid, alkyl (meth) acrylate, vinyl alcohol, and the like.
　これらのポリオレフィン系樹脂の中でも、ポリプロピレン、エチレンとプロピレンとの共重合体、プロピレンと他のα－オレフィンとの共重合体等のプロピレンに由来する構成単位を含むポリプロピレン系樹脂が好ましい。 Among these polyolefin resins, polypropylene resins containing a structural unit derived from propylene such as polypropylene, a copolymer of ethylene and propylene, and a copolymer of propylene and other α-olefin are preferable.
＜炭素系フィラー（ｂ）＞
　粘着剤層の形成材料である粘着性組成物に含まれる炭素系フィラー（ｂ）は、粘着剤層を形成する前の粘着性組成物中に分散している炭素系フィラーであって、粘着剤層の形成過程で、当該炭素系フィラー（ｂ）同士が凝集して、炭素系フィラー（Ｂ）となり得るものである。 <Carbon filler (b)>
The carbon-based filler (b) contained in the pressure-sensitive adhesive composition which is a material for forming the pressure-sensitive adhesive layer is a carbon-based filler dispersed in the pressure-sensitive adhesive composition before forming the pressure-sensitive adhesive layer, In the formation process of the layer, the carbon fillers (b) can be aggregated to form the carbon filler (B).
　粘着性組成物中の炭素系フィラー（ｂ）の含有量は、導電性粘着シートの表面抵抗率を低下させる観点、及び導電性粘着シートの粘着力を良好とする観点から、粘着性樹脂（Ａ）１００質量部に対して、好ましくは０．０１～２０質量部、より好ましくは０．０５～１５質量部、より好ましくは０．１～１０質量部、更に好ましくは０．３～７質量部、更に好ましくは０．５～４．５質量部、より更に好ましくは０．７～３．８質量部である。
　また、粘着性組成物の全量（１００質量％）に対する炭素系フィラー（ｂ）の含有量としては、上記と同様の観点から、好ましくは０．０１～２０質量％、より好ましくは０．０５～１０質量％、より好ましくは０．１～７質量％、更に好ましくは０．２～５質量％、より更に好ましくは０．３～３．５質量％である。 The content of the carbon-based filler (b) in the adhesive composition is such that the adhesive resin (A ) Preferably from 100 to 20 parts by weight, preferably from 0.01 to 20 parts by weight, more preferably from 0.05 to 15 parts by weight, more preferably from 0.1 to 10 parts by weight, still more preferably from 0.3 to 7 parts by weight. More preferably, it is 0.5 to 4.5 parts by mass, and still more preferably 0.7 to 3.8 parts by mass.
Further, the content of the carbon-based filler (b) with respect to the total amount (100% by mass) of the pressure-sensitive adhesive composition is preferably 0.01 to 20% by mass, more preferably 0.05 to It is 10% by mass, more preferably 0.1-7% by mass, still more preferably 0.2-5% by mass, and still more preferably 0.3-3.5% by mass.
　炭素系フィラー（ｂ）の平均アスペクト比としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高くなるように、形成される粘着剤層中にて、ひも状の炭素系フィラー（Ｂ）として分散させ易くする観点から、好ましくは１００～１２００、より好ましくは１２０～１０００、更に好ましくは１３５～５００、より更に好ましくは１４０～４００である。 The average aspect ratio of the carbon-based filler (b) is a string-like carbon-based filler (in the pressure-sensitive adhesive layer formed so that the occupied area ratio of the carbon-based filler (B) on the pasting surface is increased. From the viewpoint of facilitating dispersion as B), it is preferably 100 to 1200, more preferably 120 to 1000, still more preferably 135 to 500, and still more preferably 140 to 400.
　なお、本明細書において、「炭素系フィラー（ｂ）のアスペクト比」とは、対象となる炭素系フィラー（ｂ）の短辺の長さ（Ｌ）に対する長辺の長さ（Ｈ）の割合、つまり「長辺の長さ（Ｈ）／短辺の長さ（Ｌ）」より算出される値である。また、「平均アスペクト比」とは、対象となる炭素系フィラー（ｂ）１０個の算出した当該「アスペクト比」の平均値である。
　また、炭素系フィラー（ｂ）の長辺の長さ（Ｈ）とは、対象となる炭素系フィラー（ｂ）の高さ方向（長尺方向）の長さを意味する。実際の測定においては、対象となる炭素系フィラー（ｂ）の最も離れた２地点の距離を「長辺の長さ（Ｈ）」としてもよい。
　一方、炭素系フィラー（ｂ）の短辺の長さ（Ｌ）とは、対象となる炭素系フィラーの任意の点における接線方向に対して垂直に切断したときの切断面のうち面積が最大となる切断面において、当該断面が円又は楕円であれば、直径又は長径であり、当該断面が多角形であれば、当該多角形の辺のうち最長の辺の長さを意味する。 In the present specification, the “aspect ratio of the carbon-based filler (b)” is the ratio of the length (H) of the long side to the length (L) of the short side of the target carbon-based filler (b). That is, it is a value calculated from “long side length (H) / short side length (L)”. Further, the “average aspect ratio” is an average value of the “aspect ratio” calculated for 10 carbon fillers (b) as targets.
Further, the length (H) of the long side of the carbon-based filler (b) means the length in the height direction (long direction) of the target carbon-based filler (b). In actual measurement, the distance between the two most distant points of the carbon filler (b) as a target may be defined as “long side length (H)”.
On the other hand, the short side length (L) of the carbon-based filler (b) is the maximum area of the cut surface when cut perpendicular to the tangential direction at an arbitrary point of the target carbon-based filler. In the cut surface, if the cross section is a circle or an ellipse, it is a diameter or a long diameter, and if the cross section is a polygon, it means the length of the longest side among the sides of the polygon.
　炭素系フィラー（ｂ）の長辺の長さ（Ｈ）の平均としては、好ましくは０．０１～２０００μｍ、より好ましくは０．１～１０００μｍ、更に好ましくは０．３～５００μｍ、より更に好ましくは０．５～１００μｍである。 The average length (H) of the long side of the carbon-based filler (b) is preferably 0.01 to 2000 μm, more preferably 0.1 to 1000 μm, still more preferably 0.3 to 500 μm, and still more preferably. 0.5 to 100 μm.
　炭素系フィラー（ｂ）の短辺の長さ（Ｌ）の平均としては、好ましくは１～１０００ｎｍ、より好ましくは２～７５０ｎｍ、より好ましくは３～５００ｎｍ、更に好ましくは５～１００ｎｍ、より更に好ましくは７～５０ｎｍである。 The average short side length (L) of the carbon-based filler (b) is preferably 1 to 1000 nm, more preferably 2 to 750 nm, more preferably 3 to 500 nm, still more preferably 5 to 100 nm, and still more preferably. Is 7 to 50 nm.
　炭素系フィラー（ｂ）の形状としては、貼付表面上の炭素系フィラー（Ｂ）の占有面積率が高くなるように、粘着剤層中にて炭素系フィラー（Ｂ）を均一に分散し得るような形状であれば特に制限はないが、柱状、筒状、錘状、繊維状、及びこれらを組み合わせた形状が好ましく、柱状、筒状、繊維状、及びこれらを組み合わせた形状がより好ましい。
　なお、炭素系フィラー（ｂ）としては、上記観点から、毛糸のような、複数の単糸が絡み合ってなる繊維状物によって形成された形状を有する炭素系フィラーが好ましく、複数の単糸が絡み合ってなる繊維状物によって形成された筒状の炭素系フィラーがより好ましい。 As the shape of the carbon-based filler (b), the carbon-based filler (B) can be uniformly dispersed in the pressure-sensitive adhesive layer so that the occupied area ratio of the carbon-based filler (B) on the pasting surface is increased. The shape is not particularly limited as long as it is a simple shape, but a columnar shape, a cylindrical shape, a weight shape, a fiber shape, and a combination thereof are preferable, and a columnar shape, a cylinder shape, a fiber shape, and a combination thereof are more preferable.
From the above viewpoint, the carbon-based filler (b) is preferably a carbon-based filler having a shape formed by a fibrous material in which a plurality of single yarns are intertwined, such as wool, and the plurality of single yarns are intertwined. A cylindrical carbon-based filler formed of a fibrous material is more preferable.
　炭素系フィラー（ｂ）としては、炭素原子を含む導電性フィラーが挙げられ、具体的には、カーボンナノ材料、カーボンブラック、ミルド炭素繊維、黒鉛等が挙げられる。
　これらの中でも、形成される粘着剤層の表面抵抗率を低下させ、且つ粘着力を良好とする観点から、カーボンナノ材料が好ましい。
　カーボンナノ材料は、六員環配列構造を主構造とするグラファイトシートを含む物質からなるものであるが、グラファイト構造中にホウ素原子や窒素原子等の炭素原子以外の原子を含有していてもよく、カーボンナノ材料が他の物質を内包している形態であってもよく、さらに、カーボンナノ材料が他の導電性物質に修飾されている形態であってもよい。 Examples of the carbon-based filler (b) include conductive fillers containing carbon atoms, and specific examples include carbon nanomaterials, carbon black, milled carbon fiber, and graphite.
Among these, carbon nanomaterials are preferable from the viewpoints of reducing the surface resistivity of the formed pressure-sensitive adhesive layer and improving the adhesive strength.
The carbon nanomaterial is composed of a substance including a graphite sheet having a six-membered ring arrangement as a main structure, but the graphite structure may contain atoms other than carbon atoms such as boron atoms and nitrogen atoms. The carbon nanomaterial may be in a form containing another substance, and the carbon nanomaterial may be in a form modified with another conductive substance.
　カーボンナノ材料としては、例えば、カーボンナノチューブ（ＣＮＴ）、カーボンナノファイバー、カーボンナノホーン、カーボンナノコーン、フラーレン等が挙げられ、カーボンナノチューブが好ましい。
　カーボンナノチューブは、炭素６員環構造を主構造とするグラファイト（黒鉛）シートが円筒状に閉じた構造を有する筒状の炭素多面体である。
　カーボンナノチューブには、１層の黒鉛シートが円筒状に閉じた構造を有する単層カーボンナノチューブと、２層の黒鉛シートが円筒状に閉じた構造を有する二層カーボンナノチューブと、黒鉛シートが３層以上同心筒状に閉じた多層構造を有する多層カーボンナノチューブとがあり、これらのうちのいずれか２種以上を併用することもできる。 Examples of the carbon nanomaterial include carbon nanotube (CNT), carbon nanofiber, carbon nanohorn, carbon nanocone, fullerene, and the like, and carbon nanotube is preferable.
The carbon nanotube is a cylindrical carbon polyhedron having a structure in which a graphite (graphite) sheet mainly having a carbon 6-membered ring structure is closed in a cylindrical shape.
The carbon nanotube includes a single-walled carbon nanotube having a structure in which a single-layer graphite sheet is closed in a cylindrical shape, a double-walled carbon nanotube having a structure in which a two-layer graphite sheet is closed in a cylindrical shape, and a three-layered graphite sheet There are multi-walled carbon nanotubes having a multi-layered structure concentrically closed as described above, and any two or more of these can be used in combination.
＜粘着付与剤＞
　粘着剤層の形成材料である粘着性組成物は、更に粘着付与剤を含有してもよい。
　特に、粘着性樹脂（Ａ）として、上述のウレタン系樹脂及びＰＩＢ系樹脂を用いる場合には、形成される粘着剤層の粘着力を向上させる観点から、粘着付与剤を含有することが好ましい。
　なお、この粘着付与剤の質量平均分子量（Ｍｗ）は、通常１万未満であり、上述の粘着性樹脂（Ａ）とは区別されるものである。
　粘着付与剤の質量平均分子量（Ｍｗ）は、形成される粘着剤層の粘着力を向上させる観点から、好ましくは４００～４０００、より好ましくは８００～１５００である。 <Tackifier>
The pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a tackifier.
In particular, when the above-mentioned urethane-based resin and PIB-based resin are used as the adhesive resin (A), it is preferable to contain a tackifier from the viewpoint of improving the adhesive strength of the formed adhesive layer.
In addition, the mass average molecular weight (Mw) of this tackifier is usually less than 10,000, and is distinguished from the above-mentioned adhesive resin (A).
The mass average molecular weight (Mw) of the tackifier is preferably 400 to 4000, more preferably 800 to 1500, from the viewpoint of improving the adhesive strength of the formed pressure-sensitive adhesive layer.
　粘着付与剤の軟化点としては、好ましくは１１０℃以上、より好ましくは１１０～１８０℃、更に好ましくは１１５～１７５℃、より更に好ましくは１２０～１７０℃である。
　なお、本発明において、粘着付与剤の「軟化点」は、ＪＩＳ　Ｋ　２５３１に準拠して測定した値を意味する。 The softening point of the tackifier is preferably 110 ° C. or higher, more preferably 110 to 180 ° C., still more preferably 115 to 175 ° C., and still more preferably 120 to 170 ° C.
In the present invention, the “softening point” of the tackifier means a value measured according to JIS K2531.
　粘着付与剤としては、例えば、ロジン樹脂、ロジンフェノール樹脂、及びそのエステル化合物等のロジン系樹脂；これらロジン系樹脂を水素化した水素化ロジン系樹脂；テルペン樹脂、芳香族変性テルペン樹脂、テルペンフェノール系樹脂等のテルペン系樹脂；これらテルペン系樹脂を水素化した水素化テルペン樹脂；石油ナフサの熱分解で生成するペンテン、イソプレン、ピペリン、１．３－ペンタジエン等のＣ５留分を共重合して得られるＣ５系石油樹脂及びこのＣ５系石油樹脂の水素化石油樹脂；石油ナフサの熱分解で生成するインデン、ビニルトルエン、α－又はβ－メチルスチレン等のＣ９留分を共重合して得られるＣ９系石油樹脂及びこのＣ９系石油樹脂を水素化石油樹脂；等が挙げられる。
　なお、本発明において、粘着付与剤は、単独で又は軟化点や構造が異なる２種以上を併用してもよい。 Examples of the tackifier include rosin resins such as rosin resins, rosin phenol resins, and ester compounds thereof; hydrogenated rosin resins obtained by hydrogenating these rosin resins; terpene resins, aromatic modified terpene resins, terpene phenols Terpene resins such as pentene resins; hydrogenated terpene resins obtained by hydrogenating these terpene resins; copolymerization of C5 fractions such as pentene, isoprene, piperine, 1.3-pentadiene produced by thermal decomposition of petroleum naphtha C5 petroleum resin obtained and hydrogenated petroleum resin of this C5 petroleum resin; obtained by copolymerization of C9 fraction such as indene, vinyltoluene, α- or β-methylstyrene generated by thermal decomposition of petroleum naphtha C9 petroleum resin and hydrogenated petroleum resin of this C9 petroleum resin.
In the present invention, the tackifiers may be used alone or in combination of two or more different softening points and structures.
　粘着性組成物中の粘着付与剤の含有量は、粘着性樹脂（Ａ）１００質量部に対して、好ましくは１～２００質量部、より好ましくは５～１６０質量部、更に好ましくは１０～１２０質量部である。
　なお、粘着性樹脂（Ａ）がアクリル系樹脂を含む場合、当該粘着付与剤の含有量は、アクリル系樹脂１００質量部に対して、好ましくは１～１００質量部、より好ましくは５～５０質量部、更に好ましくは１０～４０質量部である。
　粘着性樹脂（Ａ）がウレタン系樹脂を含む場合、当該粘着付与剤の含有量は、ウレタン系樹脂１００質量部に対して、好ましくは５～２００質量部、より好ましくは４０～１６０質量部、更に好ましくは８０～１２０質量部である。
　粘着性樹脂（Ａ）がＰＩＢ系樹脂を含む場合、当該粘着付与剤の含有量は、ＰＩＢ系樹脂１００質量部に対して、好ましくは５～１００質量部、より好ましくは１０～８０質量部、更に好ましくは１５～４０質量部である。
　粘着性樹脂（Ａ）がポリエステル系樹脂を含む場合、当該粘着付与剤の含有量は、ポリエステル系樹脂１００質量部に対して、好ましくは５～１００質量部、より好ましくは１５～８０質量部、更に好ましくは２５～６０質量部である。
　粘着性樹脂（Ａ）がポリオレフィン系樹脂を含む場合、当該粘着付与剤の含有量は、ポリオレフィン系樹脂１００質量部に対して、好ましくは５～１００質量部、より好ましくは１５～８０質量部、更に好ましくは２５～６０質量部である。 The content of the tackifier in the adhesive composition is preferably 1 to 200 parts by weight, more preferably 5 to 160 parts by weight, and still more preferably 10 to 120 parts by weight with respect to 100 parts by weight of the adhesive resin (A). Part by mass.
When the adhesive resin (A) contains an acrylic resin, the content of the tackifier is preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass with respect to 100 parts by mass of the acrylic resin. Part, more preferably 10 to 40 parts by weight.
When the adhesive resin (A) contains a urethane resin, the content of the tackifier is preferably 5 to 200 parts by mass, more preferably 40 to 160 parts by mass with respect to 100 parts by mass of the urethane resin. More preferably, it is 80 to 120 parts by mass.
When the adhesive resin (A) contains a PIB resin, the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 10 to 80 parts by mass, with respect to 100 parts by mass of the PIB resin. More preferably, it is 15 to 40 parts by mass.
When the adhesive resin (A) contains a polyester resin, the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 15 to 80 parts by mass with respect to 100 parts by mass of the polyester resin. More preferably, it is 25 to 60 parts by mass.
When the adhesive resin (A) contains a polyolefin resin, the content of the tackifier is preferably 5 to 100 parts by mass, more preferably 15 to 80 parts by mass with respect to 100 parts by mass of the polyolefin resin. More preferably, it is 25 to 60 parts by mass.
＜架橋剤＞
　粘着剤層の形成材料である粘着性組成物は、更に架橋剤を含有してもよい。
　特に、粘着性樹脂（Ａ）として、上述のアクリル系樹脂（特に、上述の官能基を有するアクリル系樹脂）を用いる場合には、形成される粘着剤層の粘着力を向上させる観点から、架橋剤を含有することが好ましい。
　架橋剤としては、例えば、イソシアネート系架橋剤、エポキシ系架橋剤、アジリジン系架橋剤、金属キレート系架橋剤、アミン系架橋剤、アミノ樹脂系架橋剤等が挙げられる。これらの架橋剤は、単独で又は２種以上を併用してもよい。
　これらの中でも、導電性粘着シートの粘着力を向上させる観点から、イソシアネート系架橋剤が好ましい。 <Crosslinking agent>
The pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a crosslinking agent.
In particular, when the above-mentioned acrylic resin (particularly, the acrylic resin having the above-mentioned functional group) is used as the adhesive resin (A), crosslinking is performed from the viewpoint of improving the adhesive strength of the formed adhesive layer. It is preferable to contain an agent.
Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, a metal chelate crosslinking agent, an amine crosslinking agent, and an amino resin crosslinking agent. These crosslinking agents may be used alone or in combination of two or more.
Among these, from the viewpoint of improving the adhesive strength of the conductive adhesive sheet, an isocyanate-based crosslinking agent is preferable.
　イソシアネート系架橋剤としては、例えば、２，４－トリレンジイソシアネート、２，６－トリレンジイソシアネート、１，３－キシリレンジイソシアネート、１，４－キシリレンジイソシアネート、ジフェニルメタン－４，４’－ジイソシアネート、ジフェニルメタン－２，４’－ジイソシアネート、３－メチルジフェニルメタンジイソシアネート、ヘキサメチレンジイソシアネート、イソホロンジイソシアネート、ジシクロヘキシルメタン－４，４’－ジイソシアネート、ジシクロヘキシルメタン－２，４’－ジイソシアネート、リジンイソシアネート等の多価イソシアネート化合物が挙げられる。
　また、多価イソシアネート化合物は、上記化合物のトリメチロールプロパンアダクト型変性体、水と反応させたビュウレット型変性体、イソシアヌレート環を含むイソシアヌレート型変性体であってもよい。 Examples of the isocyanate-based crosslinking agent include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4′-diisocyanate, Polyvalent isocyanate compounds such as diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate Is mentioned.
Further, the polyvalent isocyanate compound may be a trimethylolpropane adduct type modified product of the above compound, a burette type modified product reacted with water, or an isocyanurate type modified product containing an isocyanurate ring.
　粘着性組成物中の架橋剤の含有量は、粘着性樹脂（Ａ）１００質量部に対して、好ましくは０．０１～１５質量部、より好ましくは０．０５～１０質量部、更に好ましくは０．１～５質量部である。 The content of the crosslinking agent in the adhesive composition is preferably 0.01 to 15 parts by mass, more preferably 0.05 to 10 parts by mass, and still more preferably 100 parts by mass of the adhesive resin (A). 0.1 to 5 parts by mass.
＜硬化促進剤＞
　粘着剤層の形成材料である粘着性組成物は、更に硬化促進剤を含有してもよい。
　特に、粘着性樹脂（Ａ）として、上述のシリル基含有ウレタン系樹脂を含有する場合、当該シリル基含有ウレタン系樹脂のシリル基同士の架橋反応を促進させ、架橋後の粘着性組成物の粘着物性をより向上させる観点から、硬化促進剤を含有することが好ましい。
　なお、この硬化促進剤（Ｅ）は、触媒として機能する。 <Curing accelerator>
The pressure-sensitive adhesive composition which is a material for forming the pressure-sensitive adhesive layer may further contain a curing accelerator.
In particular, when the above-mentioned silyl group-containing urethane resin is contained as the adhesive resin (A), the crosslinking reaction between the silyl groups of the silyl group-containing urethane resin is promoted, and the pressure-sensitive adhesive composition is crosslinked. From the viewpoint of further improving the physical properties, it is preferable to contain a curing accelerator.
In addition, this hardening accelerator (E) functions as a catalyst.
　硬化促進剤としては、アルミ系触媒、チタン系触媒、ジルコニウム系触媒、及び三フッ化ホウ素系触媒からなる群から選ばれる１種以上が好ましい。
　アルミ系触媒としては、アルミニウムのアルコキシド、アルミニウムキレート、塩化アルミニウム（III）が好ましい。
　チタン系触媒としては、チタンのアルコキシド、チタンキレート、塩化チタン（IV）が好ましい。
　ジルコニウム系触媒としては、ジルコニウムのアルコキシド、ジルコニウムキレート、塩化ジルコニウム（IV）が好ましい。
　三フッ化ホウ素系触媒としては、三フッ化ホウ素モノエチルアミン錯体等の三フッ化ホウ素のアミン錯体や、アルコール錯体が好ましい。 The curing accelerator is preferably one or more selected from the group consisting of an aluminum catalyst, a titanium catalyst, a zirconium catalyst, and a boron trifluoride catalyst.
As the aluminum catalyst, aluminum alkoxide, aluminum chelate, and aluminum chloride (III) are preferable.
As the titanium-based catalyst, titanium alkoxide, titanium chelate, and titanium (IV) chloride are preferable.
As the zirconium-based catalyst, zirconium alkoxide, zirconium chelate, and zirconium (IV) chloride are preferable.
As the boron trifluoride-based catalyst, an amine complex of boron trifluoride such as boron trifluoride monoethylamine complex or an alcohol complex is preferable.
　硬化促進剤の含有量としては、粘着性樹脂（Ａ）１００質量部に対して、好ましくは０．００１～２０質量部、より好ましくは０．０１～１０質量部、更に好ましくは０．０３～５質量部である。 The content of the curing accelerator is preferably 0.001 to 20 parts by mass, more preferably 0.01 to 10 parts by mass, still more preferably 0.03 to 10 parts by mass with respect to 100 parts by mass of the adhesive resin (A). 5 parts by mass.
＜架橋助剤＞
　粘着剤層の形成材料である粘着性組成物は、更に架橋助剤を含有してもよい。
　特に、粘着性樹脂（Ａ）として、上述のシリル基含有ウレタン系樹脂を含有する場合、上記の硬化促進剤と共に、架橋助剤を組み合わせて含有することが好ましい。
　架橋助剤としては、アミノ基含有アルコキシシランが好ましい。
　アミノ基含有アルコキシシランとしては、例えば、３－アミノプロピルトリメトキシシラン、３－アミノプロピルトリエトキシシラン、Ｎ－２－（アミノエチル）－３－アミノプロピルメチルジメトキシシラン、Ｎ－２－（アミノエチル）－３－アミノプロピルトリメトキシシラン、Ｎ－２－（アミノエチル）－３－アミノプロピルトリエトキシシラン、Ｎ－フェニル－３－アミノプロピルトリメトキシシラン等が挙げられる。 <Crosslinking aid>
The pressure-sensitive adhesive composition that is a material for forming the pressure-sensitive adhesive layer may further contain a crosslinking aid.
In particular, when the above-mentioned silyl group-containing urethane resin is contained as the adhesive resin (A), it is preferable to contain a crosslinking aid in combination with the above-described curing accelerator.
As the crosslinking aid, amino group-containing alkoxysilanes are preferred.
Examples of the amino group-containing alkoxysilane include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, and N-2- (aminoethyl). ) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and the like.
　架橋助剤の含有量は、粘着性樹脂（Ａ）１００質量部に対して、好ましくは０．０１～１０質量部、より好ましくは０．０５～６質量部、更に好ましくは０．１～３質量部である。 The content of the crosslinking aid is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 6 parts by weight, still more preferably 0.1 to 3 parts by weight based on 100 parts by weight of the adhesive resin (A). Part by mass.
＜汎用添加剤＞
　粘着剤層の形成材料である粘着性組成物は、本発明の効果を損なわない範囲において、一般的な粘着剤に使用される汎用添加剤を含有してもよい。
　このような汎用添加剤としては、例えば、紫外線吸収剤、酸化防止剤、軟化剤（可塑剤）、充填剤、防錆剤、顔料、染料等が挙げられる。
　これらの汎用添加剤を配合する場合、汎用添加剤のそれぞれの配合量は、粘着性樹脂（Ａ）１００質量部に対して、好ましくは０．０１～６質量部、より好ましくは０．０１～２質量部である。 <General-purpose additive>
The pressure-sensitive adhesive composition, which is a material for forming the pressure-sensitive adhesive layer, may contain general-purpose additives used for general pressure-sensitive adhesives as long as the effects of the present invention are not impaired.
Examples of such general-purpose additives include ultraviolet absorbers, antioxidants, softeners (plasticizers), fillers, rust inhibitors, pigments, and dyes.
When these general-purpose additives are blended, the amount of each general-purpose additive is preferably 0.01 to 6 parts by mass, more preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the adhesive resin (A). 2 parts by mass.
〔炭素系フィラー（Ｂ）の占有面積率の調整法の一例〕
　本発明の導電性粘着シートが有する粘着剤層において、当該粘着剤層の貼付表面上の炭素系フィラー（Ｂ）の占有面積率を上述の範囲とするには、及び、炭素系フィラー（Ｂ）をひも状に分散させるには、下記の［１］～［５］の事項を適宜組み合わせて考慮することで、容易に調整することができる。
　なお、下記の［１］～［５］の事項はあくまで一例であって、当該事項以外の一般的な技術常識に基づいて調整することも当然可能である。 [An example of a method for adjusting the occupied area ratio of the carbon-based filler (B)]
In the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet of the present invention, the occupation area ratio of the carbon-based filler (B) on the adhesive surface of the pressure-sensitive adhesive layer is within the above range, and the carbon-based filler (B) Can be easily adjusted by appropriately combining the following items [1] to [5].
Note that the items [1] to [5] below are merely examples, and it is naturally possible to make adjustments based on general technical common sense other than the items.
［１］粘着剤層が、超音波による振動を与えて調製された、炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）を配合した後、撹拌機を用いた撹拌により調製された粘着性組成物から形成された層である。
　なお、炭素系フィラー（ｂ）の分散液と粘着性樹脂（Ａ）との混合を手動で撹拌すると、粘着性樹脂（Ａ）が存在が原因となり、炭素系フィラー（ｂ）を均一に分散させることが難しく、また、炭素系フィラー（ｂ）同士が過度に近接し、凝集体が形成し易い傾向にある点が留意事項として挙げられる。
　また、炭素系フィラー（ｂ）の分散液や粘着性組成物の調製法の詳細については、後述する導電性粘着シートの製造方法に関する「工程（１）」及び「工程（２）」に記載の事項のとおりである。 [1] The pressure-sensitive adhesive layer is prepared by mixing the adhesive resin (A) with the dispersion of the carbon-based filler (b) prepared by applying ultrasonic vibration, and then stirring with a stirrer. It is a layer formed from the adhesive composition.
When the mixture of the carbon filler (b) dispersion and the adhesive resin (A) is manually stirred, the presence of the adhesive resin (A) causes the carbon filler (b) to be uniformly dispersed. In addition, the carbon-based fillers (b) are too close to each other and tend to form aggregates.
Moreover, about the detail of the preparation method of the dispersion liquid and adhesive composition of a carbon-type filler (b), it describes in the "process (1)" and "process (2)" regarding the manufacturing method of the electroconductive adhesive sheet mentioned later. The matter is as follows.
［２］分散前の炭素系フィラー（ｂ）として、上述の範囲の平均アスペクト比を有する炭素系フィラーを用いる。 [2] A carbon filler having an average aspect ratio in the above range is used as the carbon filler (b) before dispersion.
［３］炭素系フィラー（ｂ）の平均アスペクト比の値に応じて、上記［１］の炭素系フィラー（ｂ）の分散液を調製する際の超音波による振動条件（振幅の大きさ、振動時間等）や、粘着性組成物を調製する際の撹拌機を用いた撹拌条件（回転数、撹拌時間）を適宜設定する。
　具体的な設定方法は、後述の導電性粘着シートの製造方法に関する「工程（１）」及び「工程（２）」に記載の事項のとおりである。 [3] Ultrasonic vibration conditions (amplitude magnitude, vibration when preparing a dispersion of the carbon filler (b) of [1] according to the value of the average aspect ratio of the carbon filler (b) Time etc.) and the stirring conditions (rotation speed, stirring time) using the stirrer at the time of preparing an adhesive composition are set suitably.
A specific setting method is as described in “Step (1)” and “Step (2)” regarding a method for manufacturing a conductive adhesive sheet, which will be described later.
［３］粘着性樹脂（Ａ）として、上述の範囲に属する質量平均分子量を有する粘着性樹脂を使用する。 [3] As the adhesive resin (A), an adhesive resin having a mass average molecular weight belonging to the above range is used.
［４］粘着性樹脂（Ａ）として、アクリル系樹脂及びウレタン系樹脂からなる群より選ばれる１種以上の粘着性樹脂を使用する。
　より詳細なアクリル系樹脂及びウレタン系樹脂の態様については、上述のとおりである。 [4] As the adhesive resin (A), one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins are used.
More detailed aspects of the acrylic resin and the urethane resin are as described above.
［５］炭素系フィラー（ｂ）として、毛糸のような、複数の単糸が絡み合ってなる繊維状物によって形成された形状を有する炭素系フィラーを使用することが好ましく、複数の単糸が絡み合ってなる繊維状物によって形成された筒状の炭素系フィラーを使用することがより好ましい。
　このような炭素系フィラーを用いることで、粘着剤層の形成過程で、網目状のネットワークを形成し易く、貼付表面上の炭素系フィラー（Ｂ）の占有面積率を上述の範囲に調整し易い。 [5] As the carbon-based filler (b), it is preferable to use a carbon-based filler having a shape formed by a fibrous material in which a plurality of single yarns are entangled, such as wool, and the plurality of single yarns are entangled. It is more preferable to use a cylindrical carbon-based filler formed of a fibrous material.
By using such a carbon-based filler, it is easy to form a network network in the process of forming the pressure-sensitive adhesive layer, and it is easy to adjust the occupation area ratio of the carbon-based filler (B) on the pasting surface to the above range. .
〔基材〕
　本発明の一態様の導電性粘着シートに用いる基材としては、導電性粘着シートの使用目的に応じて適宜選択されるが、絶縁性材料を含む絶縁性基材であってもよく、金属等の導電性材料を含む導電性基材であってもよい。 〔Base material〕
The base material used for the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is appropriately selected according to the purpose of use of the conductive pressure-sensitive adhesive sheet. The electroconductive base material containing the electroconductive material of this may be sufficient.
　本発明において、絶縁性基材とは、表面抵抗率が１．０×１０１４Ω／□以上（好ましくは１．０×１０１６Ω／□以上）の基材を指す。
　絶縁性基材としては、例えば、上質紙、アート紙、コート紙、グラシン紙等やこれらの紙基材にポリエチレン等の熱可塑性樹脂をラミネートしたラミネート紙等の各種紙類；不織布等の多孔質材料；ポリエチレン樹脂、ポリプロピレン樹脂等のポリオレフィン樹脂、ポリブチレンテレフタレート樹脂、ポリエチレンテレフタレート樹脂等のポリエステル樹脂、アセテート樹脂、ＡＢＳ樹脂、ポリスチレン樹脂、塩化ビニル樹脂等からなるプラスチックフィルム又はシート；これらの樹脂の混合物からなるプラスチックフィルム又はシート；これらのプラスチックフィルム又はシートの積層体からなるプラスチックフィルム又はシート等が挙げられる。
　なお、プラスチックフィルム又はシート等の基材は、未延伸でもよいし、縦又は横等の一軸方向あるいは二軸方向に延伸されていてもよい。
　また、これらの絶縁性基材は、さらに紫外線吸収剤、光安定剤、酸化防止剤、帯電防止剤、スリップ剤、アンチブロッキング剤、着色剤等が含有されていてもよい。 In the present invention, an insulating substrate refers to a substrate having a surface resistivity of 1.0 × 10 14 Ω / □ or more (preferably 1.0 × 10 16 Ω / □ or more).
Examples of the insulating base material include various types of paper such as fine paper, art paper, coated paper, glassine paper, and laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials; Material: Polyolefin resin such as polyethylene resin and polypropylene resin, Polybutylene terephthalate resin, Polyester resin such as polyethylene terephthalate resin, Plastic film or sheet made of acetate resin, ABS resin, polystyrene resin, vinyl chloride resin, etc .; Mixture of these resins A plastic film or sheet comprising: a plastic film or sheet comprising a laminate of these plastic films or sheets.
The base material such as a plastic film or sheet may be unstretched, or may be stretched in a uniaxial direction or a biaxial direction such as longitudinal or lateral.
These insulating base materials may further contain an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an antiblocking agent, a colorant, and the like.
　導電性基材としては、例えば、金属箔、当該金属箔を上述の絶縁性基材を形成する樹脂等でラミネートしたフィルム又はシート、上述の絶縁性基材の表面に金属蒸着処理を行ったフィルム又はシート、上述の絶縁性基材の表面に帯電防止処理を行ったフィルム又はシート、メッシュ状に金属線を編んだシート等が挙げられる。
　なお、導電性基材に用いられる金属としては、例えば、アルミニウム、銅、銀、金等が挙げられる。 Examples of the conductive substrate include a metal foil, a film or sheet obtained by laminating the metal foil with a resin or the like that forms the above-described insulating substrate, and a film obtained by performing a metal deposition process on the surface of the above-described insulating substrate. Or the sheet | seat, the film or sheet which performed the antistatic process on the surface of the above-mentioned insulating base material, the sheet | seat which knitted the metal wire in mesh shape, etc. are mentioned.
In addition, as a metal used for an electroconductive base material, aluminum, copper, silver, gold | metal | money etc. are mentioned, for example.
　基材の厚さは、特に制限はないが、取り扱い易さの観点から、好ましくは１０～２５０μｍ、より好ましくは１５～２００μｍ、更に好ましくは２０～１５０μｍである。 The thickness of the substrate is not particularly limited, but is preferably 10 to 250 μm, more preferably 15 to 200 μm, and still more preferably 20 to 150 μm from the viewpoint of ease of handling.
　基材がプラスチックフィルム又はシートである場合、基材と粘着剤層との密着性を向上させる観点から、必要に応じて、基材の表面に対し酸化法や凹凸化法等の表面処理を施すことが好ましい。
　酸化法としては、特に限定されず、例えば、コロナ放電処理法、プラズマ処理法、クロム酸酸化（湿式）、火炎処理、熱風処理、オゾン・紫外線照射処理等が挙げられる。また、凹凸化法としては、特には限定されず、例えば、サンドブラスト法、溶剤処理法等が挙げられる。これらの表面処理は、基材の種類に応じて適宜選定されるが、粘着剤層との密着性の向上効果や操作性の観点から、コロナ放電処理法が好ましい。また、プライマー処理を施すこともできる。 When the base material is a plastic film or sheet, from the viewpoint of improving the adhesion between the base material and the pressure-sensitive adhesive layer, the surface of the base material is subjected to a surface treatment such as an oxidation method or an unevenness method as necessary. It is preferable.
The oxidation method is not particularly limited, and examples thereof include a corona discharge treatment method, a plasma treatment method, chromic acid oxidation (wet), flame treatment, hot air treatment, and ozone / ultraviolet irradiation treatment. Moreover, it does not specifically limit as an uneven | corrugated method, For example, a sandblasting method, a solvent processing method, etc. are mentioned. These surface treatments are appropriately selected according to the type of the substrate, but the corona discharge treatment method is preferred from the viewpoint of improving the adhesion with the pressure-sensitive adhesive layer and operability. Moreover, primer treatment can also be performed.
〔剥離シート〕
　また、本発明の一態様の導電性粘着シートに用いる剥離シートとしては、両面剥離処理をされた剥離シートや、片面剥離処理された剥離シート等が用いられ、剥離シート用の基材上に剥離剤を塗布したもの等が挙げられる。 [Peeling sheet]
Moreover, as a peeling sheet used for the electroconductive adhesive sheet of 1 aspect of this invention, the peeling sheet by which the double-sided peeling process was carried out, the peeling sheet by which the single-sided peeling process was carried out, etc. are used, and it peels on the base material for peeling sheets. The thing etc. which apply | coated the agent are mentioned.
　剥離シート用の基材としては、例えば、グラシン紙、コート紙、上質紙等の紙基材、これらの紙基材にポリエチレン等の熱可塑性樹脂をラミネートしたラミネート紙、又はポリエチレンテレフタレート樹脂、ポリブチレンテレフタレート樹脂、ポリエチレンナフタレート樹脂等のポリエステル樹脂フィルム、ポリプロピレン樹脂、ポリエチレン樹脂等のポリオレフィン樹脂フィルム等のプラスチックフィルム等が挙げられる。
　剥離剤としては、例えば、シリコーン系樹脂、オレフィン系樹脂、イソプレン系樹脂、ブタジエン系樹脂等のゴム系エラストマー、長鎖アルキル系樹脂、アルキド系樹脂、フッ素系樹脂等が挙げられる。 Examples of the base material for the release sheet include paper base materials such as glassine paper, coated paper, and high-quality paper, laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials, or polyethylene terephthalate resin, polybutylene. Examples thereof include polyester resin films such as terephthalate resin and polyethylene naphthalate resin, and plastic films such as polyolefin resin films such as polypropylene resin and polyethylene resin.
Examples of the release agent include rubber elastomers such as silicone resins, olefin resins, isoprene resins, and butadiene resins, long chain alkyl resins, alkyd resins, and fluorine resins.
　剥離シートの厚さは、特に制限ないが、好ましくは１０～２００μｍ、より好ましくは２５～１５０μｍである。 The thickness of the release sheet is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 150 μm.
〔導電性粘着シートの製造方法〕
　本発明の導電性粘着シートを製造する方法としては、例えば、上述の各成分を配合して粘着性組成物を調製し、更に有機溶媒を添加して希釈し、粘着性組成物の溶液の形態とし、当該溶液を上述の基材又は剥離シート上に公知の塗布及び乾燥して粘着剤層を形成して製造する方法が挙げられる。
　ただし、炭素系フィラー（Ｂ）の占有面積率をより大きくなるように分散した粘着剤層を形成し易くする観点から、本発明の導電性粘着シートの製造方法としては、下記工程（１）～（３）を有する製造方法が好ましい。
・工程（１）：超音波による振動を与えて、炭素系フィラー（ｂ）の分散液を調製する工程。
・工程（２）：工程（１）で得た分散液に、粘着性樹脂（Ａ）を配合し、撹拌翼を有する撹拌機を用いた撹拌により粘着性組成物を調製する工程。
・工程（３）：工程（２）で得た粘着性組成物を用いて粘着剤層を形成する工程。
　以下、上記工程（１）～（３）について説明する。 [Method for producing conductive adhesive sheet]
As a method for producing the conductive pressure-sensitive adhesive sheet of the present invention, for example, a pressure-sensitive adhesive composition is prepared by blending the above-described components, and further diluted by adding an organic solvent to form a pressure-sensitive adhesive composition solution. And a method of producing the adhesive layer by forming the solution on the above-mentioned substrate or release sheet by known coating and drying.
However, from the viewpoint of facilitating formation of a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is increased, the method for producing the conductive pressure-sensitive adhesive sheet of the present invention includes the following steps (1) to A production method having (3) is preferred.
Step (1): A step of preparing a dispersion of the carbon-based filler (b) by applying vibration by ultrasonic waves.
-Process (2): The process which mixes adhesive resin (A) with the dispersion liquid obtained at the process (1), and prepares an adhesive composition by stirring using the stirrer which has a stirring blade.
-Process (3): The process of forming an adhesive layer using the adhesive composition obtained at the process (2).
Hereinafter, the steps (1) to (3) will be described.
＜工程（１）＞
　工程（１）は、超音波による振動を与えて、炭素系フィラー（ｂ）の分散液を調製する工程である。
　炭素系フィラー（ｂ）は、溶媒中に分散させた分散液の形態とした上で、粘着性樹脂（Ａ）等の成分と混合することが好ましい。
　炭素系フィラー（ｂ）を分散液の形態とすることで、低粘度の状態で粘着性樹脂（Ａ）と混合することができるため、炭素系フィラー（ｂ）同士が近接し、適度に（非ひも状凝集体が形成されない程度に）凝集し易くなり、形成される粘着剤層中にて、炭素系フィラー（Ｂ）の占有面積率をより高くなるように分散させ易くなる。 <Process (1)>
Step (1) is a step of preparing a dispersion liquid of carbon-based filler (b) by applying vibration by ultrasonic waves.
The carbon-based filler (b) is preferably mixed with a component such as an adhesive resin (A) after being in the form of a dispersion liquid dispersed in a solvent.
By making the carbon-based filler (b) in the form of a dispersion, it can be mixed with the adhesive resin (A) in a low-viscosity state. Aggregation is facilitated (to the extent that no string-like aggregates are formed), and the carbon-based filler (B) is easily dispersed so as to have a higher occupied area ratio in the formed pressure-sensitive adhesive layer.
　炭素系フィラー（ｂ）の分散液の調製に用いる溶媒としては、水又は有機溶媒が挙げられ、有機溶媒が好ましい。
　炭素系フィラー（ｂ）の分散液の調製に用いる有機溶媒としては、例えば、メチルエチルケトン、アセトン、酢酸エチル、テトラヒドロフラン、ジオキサン、シクロヘキサン、ｎ－ヘキサン、トルエン、キシレン、１－プロパノール、イソプロピルアルコール、ジメチルホルムアミド、Ｎ－メチルピロリドン、ジメチルスルホキシド等が挙げられる。
　これらの有機溶媒は、単独で又は２種以上を併用してもよい。
　これらの中でも、メチルエチルケトン、酢酸エチル、トルエン、及びイソプロピルアルコールから選ばれる１種以上が好ましく、酢酸エチル及びイソプロピルアルコールから選ばれる１種以上がより好ましい。 Examples of the solvent used for the preparation of the carbon filler (b) dispersion include water and organic solvents, with organic solvents being preferred.
Examples of the organic solvent used for the preparation of the carbon filler (b) dispersion include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, 1-propanol, isopropyl alcohol, and dimethylformamide. N-methylpyrrolidone, dimethyl sulfoxide and the like.
These organic solvents may be used alone or in combination of two or more.
Among these, at least one selected from methyl ethyl ketone, ethyl acetate, toluene, and isopropyl alcohol is preferable, and at least one selected from ethyl acetate and isopropyl alcohol is more preferable.
　本工程においては、溶媒中に炭素系フィラー（ｂ）を添加し、超音波（振幅の大きさは、好ましくは１～５０μｍ、より好ましくは５～４０μｍ）による振動を一定時間与えて炭素系フィラー（ｂ）の分散液を調製する。
　炭素系フィラー（ｂ）の分散液を、超音波による振動を与えて調製することで、当該分散液中で炭素系フィラー（ｂ）同士が近接し、適度に（非ひも状凝集体が形成されない程度に）凝集し易くなる。その結果、炭素系フィラー（Ｂ）の占有面積率をより大きくなるように分散させた粘着剤層を形成し易くなる。
　炭素系フィラー（ｂ）の分散液の固形分濃度としては、好ましくは０．０１～６０質量％、より好ましくは０．０５～１０質量％、更に好ましくは０．１～３質量％である。 In this step, the carbon-based filler (b) is added to the solvent, and the vibration of the ultrasonic wave (the amplitude is preferably 1 to 50 μm, more preferably 5 to 40 μm) is given for a certain period of time. A dispersion of (b) is prepared.
By preparing a dispersion of the carbon-based filler (b) by applying vibration by ultrasonic waves, the carbon-based fillers (b) are close to each other in the dispersion and moderately (non-string aggregates are not formed. To a degree). As a result, it becomes easy to form a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is dispersed.
The solid content concentration of the carbon filler (b) dispersion is preferably 0.01 to 60% by mass, more preferably 0.05 to 10% by mass, and still more preferably 0.1 to 3% by mass.
＜工程（２）＞
　工程（２）は、工程（１）で得た炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）や上述の他の添加剤を配合し、撹拌翼を有する撹拌機を用いた撹拌により粘着性組成物を調製する工程である。
　本工程において、炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）や他の添加剤を配合する際に、更に有機溶媒を添加して希釈し、粘着性組成物の溶液の形態としてもよい。 <Step (2)>
In step (2), an adhesive resin (A) or the above-mentioned other additive was blended into the carbon-based filler (b) dispersion obtained in step (1), and a stirrer having a stirring blade was used. This is a step of preparing an adhesive composition by stirring.
In this step, when the adhesive resin (A) and other additives are added to the dispersion of the carbon-based filler (b), an organic solvent is further added and diluted to form a solution of the adhesive composition It is good.
　粘着性組成物の調製に用いる有機溶媒としては、例えば、メチルエチルケトン、アセトン、酢酸エチル、テトラヒドロフラン、ジオキサン、シクロヘキサン、ｎ－ヘキサン、トルエン、キシレン、１－プロパノール、イソプロピルアルコール、ジメチルホルムアミド、Ｎ－メチルピロリドン、ジメチルスルホキシド等が挙げられる。
　これらの有機溶媒は、単独で又は２種以上を併用してもよい。
　これらの中でも、メチルエチルケトン、酢酸エチル、トルエン、及びイソプロピルアルコールから選ばれる１種以上が好ましく、酢酸エチル及びイソプロピルアルコールから選ばれる１種以上がより好ましい。
　なお、これらの有機溶媒は、粘着性樹脂（Ａ）の合成時に使用した有機溶媒や、炭素系フィラー（ｂ）を分散液の形態に調製した際に用いた有機溶媒をそのまま用いてもよいし、得られる粘着性組成物の溶液を均一に塗布できるように、粘着性樹脂（Ａ）成分の合成時や炭素系フィラー（ｂ）の分散液に使用している有機溶媒以外の１種以上の有機溶媒を加えてもよい。 Examples of the organic solvent used for preparing the adhesive composition include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, 1-propanol, isopropyl alcohol, dimethylformamide, N-methylpyrrolidone. And dimethyl sulfoxide.
These organic solvents may be used alone or in combination of two or more.
Among these, at least one selected from methyl ethyl ketone, ethyl acetate, toluene, and isopropyl alcohol is preferable, and at least one selected from ethyl acetate and isopropyl alcohol is more preferable.
As these organic solvents, the organic solvent used in the synthesis of the adhesive resin (A) or the organic solvent used when the carbon-based filler (b) is prepared in the form of a dispersion may be used as it is. More than one organic solvent other than the organic solvent used in the dispersion of the carbon-based filler (b) or during the synthesis of the adhesive resin (A) component so that the resulting adhesive composition solution can be uniformly applied An organic solvent may be added.
　粘着性組成物の溶液の固形分濃度としては、好ましくは１～９０質量％、より好ましくは３～８０質量％、更に好ましくは５～７０質量％、より更に好ましくは７～６０質量％である。 The solid content concentration of the adhesive composition solution is preferably 1 to 90% by mass, more preferably 3 to 80% by mass, still more preferably 5 to 70% by mass, and even more preferably 7 to 60% by mass. .
　本工程においては、炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）を配合し、撹拌翼を有する撹拌機を用いた撹拌により、混合し、粘着性組成物を調製する。
　粘着性組成物を、撹拌機を用いて調製することで、当該粘着性組成物中で炭素系フィラー（ｂ）同士が均一に近接し、適度に（非ひも状凝集体が形成されない程度に）凝集し易くなる。その結果、炭素系フィラー（Ｂ）の占有面積率をより大きくなるように分散させた粘着剤層を形成し易くなる。
　一方、手動による撹拌の調製法の場合、粘着性樹脂（Ａ）の存在が原因となり、炭素系フィラー（ｂ）を均一に分散させることが難しく、また、炭素系フィラー（ｂ）同士が過度に近接し、凝集体が形成し易い傾向にある。そのため、形成される粘着剤層中で炭素系フィラー（Ｂ）の分散が不均一であり、また凝集体を形成し易く、炭素系フィラー（Ｂ）の占有面積率が高くなり難い。 In this step, the adhesive resin (A) is blended with the dispersion liquid of the carbon-based filler (b) and mixed by stirring using a stirrer having a stirring blade to prepare an adhesive composition.
By preparing the pressure-sensitive adhesive composition using a stirrer, the carbon fillers (b) are uniformly close to each other in the pressure-sensitive adhesive composition, and moderately (to the extent that non-string aggregates are not formed). Aggregates easily. As a result, it becomes easy to form a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is dispersed.
On the other hand, in the case of manual stirring preparation method, due to the presence of the adhesive resin (A), it is difficult to disperse the carbon filler (b) uniformly, and the carbon fillers (b) are excessively mixed. They tend to be close and form aggregates easily. Therefore, the dispersion of the carbon-based filler (B) is not uniform in the formed pressure-sensitive adhesive layer, and aggregates are easily formed, and the occupied area ratio of the carbon-based filler (B) is unlikely to increase.
　撹拌機によって撹拌の際の、撹拌機が有する撹拌翼の回転数としては、上記観点から、好ましくは５００～１００００ｒｐｍ、より好ましくは１０００～５０００ｒｐｍ、更に好ましくは１２００～３５００ｒｐｍ、より更に好ましくは１５００～３０００ｒｐｍである。 From the above viewpoint, the rotation speed of the stirring blade of the stirrer when stirring by the stirrer is preferably 500 to 10,000 rpm, more preferably 1000 to 5000 rpm, still more preferably 1200 to 3500 rpm, and still more preferably 1500 to 3000 rpm.
　なお、炭素系フィラー（Ｂ）の占有面積率をより大きくなるように分散させた粘着剤層を形成し易くする観点から、分散前の炭素系フィラー（ｂ）として、平均アスペクト比が比較的大きな炭素系フィラー（例えば、平均アスペクト比が３００以上の炭素系フィラー）を用いる場合には、撹拌翼の回転数は、比較的速くすることが好ましく、具体的には３０００ｒｐｍ以上とすることが好ましい。
　一方、平均アスペクト比が比較的小さな炭素系フィラー（例えば、平均アスペクト比が１５０以下の炭素系フィラー）を用いる場合には、撹拌翼の回転数は、比較的遅くすることが好ましく、具体的には１５００ｒｐｍ以下とすることが好ましい。 In addition, from the viewpoint of easily forming a pressure-sensitive adhesive layer in which the occupied area ratio of the carbon-based filler (B) is increased, the average aspect ratio is relatively large as the carbon-based filler (b) before dispersion. When a carbon-based filler (for example, a carbon-based filler having an average aspect ratio of 300 or more) is used, the rotational speed of the stirring blade is preferably relatively high, and specifically, 3000 rpm or more is preferable.
On the other hand, when a carbon-based filler having a relatively small average aspect ratio (for example, a carbon-based filler having an average aspect ratio of 150 or less) is used, the rotation speed of the stirring blade is preferably relatively slow. Is preferably 1500 rpm or less.
＜工程（３）＞
　工程（３）は、工程（２）で得た粘着性組成物を用いて粘着剤層を形成する工程である。
　当該粘着剤層は、基材又は剥離材上に、粘着性組成物を塗布して塗布膜を形成して、当該塗布膜を乾燥して形成することができる。
　基材や剥離シート上への粘着性組成物の塗布方法としては、例えば、スピンコート法、スプレーコート法、バーコート法、ナイフコート法、ロールナイフコート法、ロールコート法、ブレードコート法、ダイコート法、グラビアコート法等が挙げられる。 <Step (3)>
Step (3) is a step of forming a pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition obtained in step (2).
The pressure-sensitive adhesive layer can be formed by applying a pressure-sensitive adhesive composition on a substrate or a release material to form a coating film, and then drying the coating film.
Examples of the method for applying the adhesive composition onto the substrate or release sheet include spin coating, spray coating, bar coating, knife coating, roll knife coating, roll coating, blade coating, and die coating. Method, gravure coating method and the like.
　また、基材や剥離シート上に粘着性組成物の溶液を塗布し塗布膜を形成した後、乾燥処理をし、塗布膜中に含まれる溶媒を除去することが好ましい。
　乾燥処理としては、乾燥温度２５～１５０℃（好ましくは５０～１２０℃）で、１０秒～５０分（好ましくは３０秒～３０分）で乾燥することが好ましい。
　さらに、粘着剤層の凝集力を高めるために、当該乾燥処理の後、例えば、２３℃、５０％ＲＨ（相対湿度）の環境下で７日間～３０日程度放置して、粘着性組成物からなる粘着剤層（塗布膜）を十分に架橋させることが好ましい。 Moreover, after apply | coating the solution of an adhesive composition on a base material or a peeling sheet and forming a coating film, it is preferable to dry-process and remove the solvent contained in a coating film.
As the drying treatment, it is preferable to dry at a drying temperature of 25 to 150 ° C. (preferably 50 to 120 ° C.) for 10 seconds to 50 minutes (preferably 30 seconds to 30 minutes).
Further, in order to increase the cohesive strength of the pressure-sensitive adhesive layer, after the drying treatment, for example, it is allowed to stand in an environment of 23 ° C. and 50% RH (relative humidity) for about 7 days to 30 days. It is preferable to sufficiently crosslink the pressure-sensitive adhesive layer (coating film).
　基材又は剥離シート上に粘着剤層を形成後、必要に応じて、当該粘着剤層上に基材又は剥離シートを適宜貼り合わせることで、本発明の一態様の導電性粘着シートを製造することができる。 After forming the pressure-sensitive adhesive layer on the base material or release sheet, the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention is produced by appropriately bonding the base material or release sheet onto the pressure-sensitive adhesive layer as necessary. be able to.
〔導電性粘着シートの物性〕
　本発明の一態様の導電性粘着シートの粘着力としては、好ましくは５．０Ｎ／２５ｍｍ以上、より好ましくは７．０Ｎ／２５ｍｍ以上、更に好ましくは１０．０Ｎ／２５ｍｍ以上、より更に好ましくは１５．０Ｎ／２５ｍｍ以上である。
　なお、上記の粘着力の値は、被着体がステンレス板である場合の粘着力であって、実施例に記載の方法により測定した値を意味する。 [Physical properties of conductive adhesive sheet]
The adhesive strength of the conductive adhesive sheet of one embodiment of the present invention is preferably 5.0 N / 25 mm or more, more preferably 7.0 N / 25 mm or more, still more preferably 10.0 N / 25 mm or more, and still more preferably 15 0.0 N / 25 mm or more.
In addition, the value of said adhesive force is an adhesive force when a to-be-adhered body is a stainless steel board, Comprising: The value measured by the method as described in an Example is meant.
　本発明の一態様の導電性粘着シートの表面抵抗率は、好ましくは１．０×１０１２Ω／□以下、より好ましくは１．０×１０１０Ω／□以下、より好ましくは１．０×１０９Ω／□以下、更に好ましくは３．０×１０８Ω／□以下、更に好ましくは１．０×１０７Ω／□以下、より更に好ましくは１．０×１０５Ω／□以下である。 The surface resistivity of the conductive adhesive sheet of one embodiment of the present invention is preferably 1.0 × 10 12 Ω / □ or less, more preferably 1.0 × 10 10 Ω / □ or less, more preferably 1.0 ×. 10 9 Ω / □ or less, more preferably 3.0 × 10 8 Ω / □ or less, more preferably 1.0 × 10 7 Ω / □ or less, and still more preferably 1.0 × 10 5 Ω / □ or less. is there.
　実施例及び比較例で用いた各成分の物性値は、以下に記載の方法により測定した。
＜質量平均分子量（Ｍｗ）＞
　ゲル浸透クロマトグラフ装置（東ソー株式会社製、製品名「ＨＬＣ－８０２０」）を用いて、下記の条件下で測定し、標準ポリスチレン換算にて測定した値を用いた。
（測定条件）
・カラム：「ＴＳＫ　ｇｕａｒｄ　ｃｏｌｕｍｎ　ＨＸＬ－Ｈ」「ＴＳＫ　ｇｅｌ　ＧＭＨＸＬ（×２）」「ＴＳＫ　ｇｅｌ　Ｇ２０００ＨＸＬ」（いずれも東ソー株式会社製）を順次連結したもの
・カラム温度：４０℃
・展開溶媒：テトラヒドロフラン
・流速：１．０ｍＬ／ｍｉｎ The physical property value of each component used in Examples and Comparative Examples was measured by the method described below.
<Mass average molecular weight (Mw)>
Using a gel permeation chromatograph (product name “HLC-8020” manufactured by Tosoh Corporation), measurement was performed under the following conditions, and values measured in terms of standard polystyrene were used.
(Measurement condition)
Column: “TSK guard column HXL-H”, “TSK gel GMHXL (× 2)”, “TSK gel G2000HXL” (both manufactured by Tosoh Corporation), column temperature: 40 ° C.
・ Developing solvent: Tetrahydrofuran ・ Flow rate: 1.0 mL / min
＜分散前の炭素系フィラーのアスペクト比＞
　走査型電子顕微鏡（株式会社日立ハイテクノロジーズ製、製品名「Ｓ－４７００」）を用いて、無作為に抽出した炭素系フィラーの粒子１０個を観察して、それぞれの長辺の長さ及び短辺の長さを測定し、粒子１０個の平均値を、そのフィラーの「長辺の長さ（Ｈ）」及び「短辺の長さ（Ｌ）」とした。また、アスペクト比（Ｈ／Ｌ）は、「長辺の長さ（Ｈ）／短辺の長さ（Ｌ）」より算出した。 <Aspect ratio of carbon filler before dispersion>
Using a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation, product name “S-4700”), ten randomly extracted carbon-based filler particles were observed, and the length and short length of each long side were observed. The length of the side was measured, and the average value of 10 particles was defined as “long side length (H)” and “short side length (L)” of the filler. The aspect ratio (H / L) was calculated from “long side length (H) / short side length (L)”.
＜軟化点＞
　ＪＩＳ　Ｋ　２５３１に準拠して測定した。 <Softening point>
It measured based on JISK2531.
製造例１（「ウレタン系樹脂（１）」の合成）
（Ｉ）シリル化剤の合成
　反応容器内に、Ｎ－アミノエチル－γ－アミノプロピルメチルジメトキシシラン１００質量部、アクリル酸メチル８３．５質量部を仕込み、窒素雰囲気下にて、８０℃で１０時間撹拌し、シリル化剤となるシラン化合物を得た。
（II）ウレタンプレポリマーの合成
　上記（Ｉ）で使用したものとは別の反応容器内に、ポリオキシプロピレンジオール（旭硝子株式会社製、製品名「ＰＭＬ　Ｓ４０１５」、質量平均分子量：１５，０００）１００質量部、イソホロンジイソシアネート２．４６質量部（ＮＣＯ／ＯＨ比＝１．７）、ジブチルスズジラウレート０．００５質量部を仕込み、窒素雰囲気下にて、８５℃で７時間反応させ、ウレタンプレポリマーを得た。
（III）「ウレタン系樹脂（１）」の合成
　上記（II）で得たウレタンプレポリマー１００質量部に対し、シリル化剤として、上記（Ｉ）で得たシラン化合物４．２１質量部を添加し、窒素雰囲気下にて、８０℃で１時間反応させた。ＩＲにて、イソシアネート基の吸収（２２６５ｃｍ－１）の消失を確認した後、反応を終了し、ポリマーを得た。
　得られた当該ポリマーは、主鎖であるポリオキシプロピレンの両末端に、下記式（９）で表される末端部分を有し、質量平均分子量（Ｍｗ）が４０，０００のシリル基含有ウレタン系樹脂（以下、「ウレタン系樹脂（１）」ともいう）と確認された。
　なお、「ウレタン系樹脂（１）」は、合成の際に、シリル化剤の原料として、Ｎ－アミノエチル－γ－アミノプロピルメチルジメトキシシランを用いたため、末端には、下記式（９）で表されるように、２官能のシリル基が導入されている。 Production Example 1 (Synthesis of “urethane resin (1)”)
(I) Synthesis of silylating agent In a reaction vessel, 100 parts by mass of N-aminoethyl-γ-aminopropylmethyldimethoxysilane and 83.5 parts by mass of methyl acrylate were charged, and 10% at 80 ° C. in a nitrogen atmosphere. The mixture was stirred for a time to obtain a silane compound to be a silylating agent.
(II) Synthesis of urethane prepolymer In a reaction container different from that used in (I) above, polyoxypropylene diol (manufactured by Asahi Glass Co., Ltd., product name “PML S4015”, mass average molecular weight: 15,000) 100 parts by mass, 2.46 parts by mass of isophorone diisocyanate (NCO / OH ratio = 1.7), 0.005 parts by mass of dibutyltin dilaurate were charged and reacted at 85 ° C. for 7 hours in a nitrogen atmosphere to obtain a urethane prepolymer. Obtained.
(III) Synthesis of “urethane resin (1)” To 100 parts by mass of the urethane prepolymer obtained in (II) above, 4.21 parts by mass of the silane compound obtained in (I) above was added as a silylating agent. And allowed to react at 80 ° C. for 1 hour in a nitrogen atmosphere. After confirming the disappearance of isocyanate group absorption (2265 cm −1 ) by IR, the reaction was terminated to obtain a polymer.
The obtained polymer has a silyl group-containing urethane system having terminal portions represented by the following formula (9) at both ends of polyoxypropylene as a main chain and a mass average molecular weight (Mw) of 40,000. It was confirmed as a resin (hereinafter also referred to as “urethane resin (1)”).
The “urethane resin (1)” was synthesized by using N-aminoethyl-γ-aminopropylmethyldimethoxysilane as a raw material for the silylating agent. As shown, a bifunctional silyl group has been introduced.
Figure JPOXMLDOC01-appb-C000009
Figure JPOXMLDOC01-appb-C000009
　実施例及び比較例で使用した各成分の詳細は以下のとおりである。
＜粘着性樹脂＞
・「アクリル系樹脂（１）」：ｎ－ブチルアクリレート（ＢＡ）及びアクリル酸（ＡＡ）からなるアクリル系樹脂（ＢＡ／ＡＡ＝９０．０／１０．０（質量部））、Ｍｗ＝７０万。
・「アクリル系樹脂（２）」：ｎ－ブチルアクリレート（ＢＡ）、メチルアクリレート（ＭＡ）、Ｎ－アクリロイルモルホリン（ＡＣＭＯ）、及び２－ヒドロキシエチルアクリレート（ＨＥＡ）からなるアクリル系樹脂（ＢＡ／ＭＡ／ＡＣＭＯ／ＨＥＡ＝８０．０／２．０／１６．０／２．０（質量部））、Ｍｗ＝６０万。
・「ウレタン系樹脂（１）」：製造例１で合成したシリル基含有ウレタン系樹脂、Ｍｗ＝４０，０００。
・「ウレタン系樹脂（２）」：商品名「ＵＳ－９０２Ａ」、一方社油脂工業株式会社製、Ｍｗ＝５６，０００。
・「ＰＩＢ系樹脂」：Ｍｗ３４万のＰＩＢ系樹脂（ＢＡＳＦ社製、商品名「オパノールＢ５０」）１００質量部（固形分比）とＭｗ２０万のＰＩＢ系樹脂（ＢＡＳＦ社製、商品名「オパノールＢ３０」）１０質量部（固形分比）とからなるＰＩＢ系混合樹脂。 Details of each component used in Examples and Comparative Examples are as follows.
<Adhesive resin>
"Acrylic resin (1)": acrylic resin (BA / AA = 90.0 / 10.0 (parts by mass)) consisting of n-butyl acrylate (BA) and acrylic acid (AA), Mw = 700,000 .
"Acrylic resin (2)": acrylic resin (BA / MA) comprising n-butyl acrylate (BA), methyl acrylate (MA), N-acryloylmorpholine (ACMO), and 2-hydroxyethyl acrylate (HEA) /ACMO/HEA=80.0/2.0/16.0/2.0 (parts by mass)), Mw = 600,000.
“Urethane resin (1)”: silyl group-containing urethane resin synthesized in Production Example 1, Mw = 40,000.
-"Urethane resin (2)": Trade name "US-902A", manufactured by Yushi Kogyo Co., Ltd., Mw = 56,000.
-"PIB resin": 100 parts by mass (solid content ratio) of a PIB resin having a Mw of 340,000 (manufactured by BASF, trade name "Opanol B50") and a PIB resin having a Mw of 200,000 (made by BASF, trade name "Opanol B30") ") A PIB-based mixed resin comprising 10 parts by mass (solid content ratio).
＜炭素系フィラー＞
・「ＣＮＴ（１）」：商品名「ＮＣ７０００」、ナノシル社製、複数の単糸が絡み合ってなる繊維状物によって形成された円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：２００（長辺の長さ（Ｈ）：２μｍ、短辺の長さ（Ｌ）：１０ｎｍ）。
・「ＣＮＴ（２）」：商品名「ＰＬＴ－ＣＮ２２」、株式会社ブラネット製、円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：１００（長辺の長さ（Ｈ）：１５μｍ、短辺の長さ（Ｌ）：１５ｎｍ）。
・「ＣＮＴ（３）」：商品名「ＣＶＤ－ＭＷＮＴ　ＣＭ－９５」、ナノテクノロジー社製、円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：１２５０（長辺の長さ（Ｈ）：１５μｍ、短辺の長さ（Ｌ）：１２ｎｍ）。
・「ＣＮＴ（４）」：商品名「ＶＧＣＦ－Ｈ」、昭和電工株式会社製、円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：５．５４（長辺の長さ（Ｈ）：６μｍ、短辺の長さ（Ｌ）：１５０ｎｍ）。
・「ＣＮＴ（５）」：商品名「Ｃ－１５０Ｐ」、Ｂａｙｅｒ社製、円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：１３３（長辺の長さ（Ｈ）：２μｍ、短辺の長さ（Ｌ）：１５ｎｍ）。
・「ＣＮＴ（６）」：商品名「Ｋ－ｎａｎｏｓ　１００Ｐ」、Ｋｏｒｅａ　Ｋｕｍｈｏ　Ｐｅｔｒｏｃｈｅｍｉｃａｌ社製、複数の単糸が絡み合ってなる繊維状物によって形成された円筒状の多層カーボンナノチューブ、分散前の平均アスペクト比（Ｈ／Ｌ）：２００（長辺の長さ（Ｈ）：２μｍ、短辺の長さ（Ｌ）：１０ｎｍ）。 <Carbon filler>
"CNT (1)": trade name "NC7000", manufactured by Nanosil, cylindrical multi-walled carbon nanotubes formed by a fibrous material in which a plurality of single yarns are intertwined, average aspect ratio before dispersion (H / L ): 200 (long side length (H): 2 μm, short side length (L): 10 nm).
“CNT (2)”: trade name “PLT-CN22”, manufactured by BRANET, Inc., cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 100 (long side length (H ): 15 μm, short side length (L): 15 nm).
“CNT (3)”: trade name “CVD-MWNT CM-95”, manufactured by Nanotechnology, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 1250 (length of long side) (H): 15 μm, short side length (L): 12 nm).
“CNT (4)”: trade name “VGCF-H”, manufactured by Showa Denko KK, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 5.54 (long side length) (H): 6 μm, short side length (L): 150 nm).
"CNT (5)": trade name "C-150P", manufactured by Bayer, cylindrical multi-walled carbon nanotube, average aspect ratio before dispersion (H / L): 133 (long side length (H): 2 μm, short side length (L): 15 nm).
"CNT (6)": trade name "K-nanos 100P", manufactured by Korea Kumho Petrochemical, cylindrical multi-walled carbon nanotubes formed by a fibrous material in which a plurality of single yarns are intertwined, average aspect before dispersion Ratio (H / L): 200 (long side length (H): 2 μm, short side length (L): 10 nm).
＜添加剤＞
・「粘着付与剤（１）」：商品名「ＹＳポリスターＮ１２５」、ヤスハラケミカル株式会社製、テルペンフェノール系樹脂、軟化点＝１２５℃、Ｍｗ＝８２０。
・「粘着付与剤（２）」：商品名「アルコンＰ－１２５」、荒川化学工業株式会社製、水素化石油樹脂、軟化点＝１２５℃。
・「架橋剤」：商品名「コロネートＬ」、東ソー株式会社製、イソシアネート系架橋剤、固形分濃度：７５質量％。
・「硬化促進剤」：三フッ化ホウ素モノエチルアミン錯体。
・「架橋助剤」：３－アミノプロピルトリメトキシシラン。 <Additives>
“Tackifier (1)”: trade name “YS Polystar N125”, manufactured by Yashara Chemical Co., Ltd., terpene phenol resin, softening point = 125 ° C., Mw = 820.
“Tackifier (2)”: trade name “Arcon P-125”, Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point = 125 ° C.
“Crosslinking agent”: trade name “Coronate L”, manufactured by Tosoh Corporation, isocyanate crosslinking agent, solid content concentration: 75 mass%.
"Curing accelerator": Boron trifluoride monoethylamine complex.
“Crosslinking aid”: 3-aminopropyltrimethoxysilane.
実施例１～４、比較例１～６
（１）炭素系フィラーの分散液の調製
　表１に示す種類及び固形分量（粘着性樹脂１００質量部（固形分）に対する固形分比）の炭素系フィラーを酢酸エチル中に添加し、超音波分散機（株式会社ソニックテクノロジー製、商品名「試験用超音波分散機ＧＳＤ６００ＡＴ」）を用いて、振幅３０μｍの超音波による振動を１５分間与えて、固形分濃度０．３質量％の炭素系フィラーの分散液を調製した。
（２）粘着性組成物の溶液の調製
　表１に示す種類の粘着性樹脂１００質量部（固形分）に対し、上記（１）で調製した炭素系フィラーの分散液（当該分散液は、表１に記載の固形分量の炭素系フィラーを含有している）を加え、更に表１に示す種類及び配合量（固形分比）の添加剤を必要に応じて添加した。そして、「超高速マルチ撹拌システム　ラボ・リューション」（商品名、プライミクス株式会社製）を用いて、回転数２０００ｒｐｍにて１０分間撹拌し、固形分濃度１０質量％の粘着性組成物の溶液を調製した。
（３）導電性粘着シートの作製
　上記（２）で調製した粘着性組成物の溶液を、剥離シート（リンテック株式会社製、製品名「ＳＰ－ＰＥＴ３８１０３１」、厚さ：３８μｍ、表面がシリコーン剥離処理されたポリエチレンテレフタレートフィルム）の剥離処理面上に、乾燥後の厚さが２０μｍとなるように塗布して塗布膜を形成し、当該塗膜を９０℃で１分間乾燥し、粘着剤層を形成した。
　そして、当該粘着剤層上に、厚さ５０μｍのポリエチレンテレフタレートフィルム（東レ株式会社製、商品名「ルミラー」）を貼り合わせて、基材付きの導電性粘着シートを作製した。 Examples 1 to 4 and Comparative Examples 1 to 6
(1) Preparation of dispersion liquid of carbon-based filler A carbon-based filler of the type and solid content (solid content ratio with respect to 100 parts by mass of adhesive resin (solid content)) shown in Table 1 is added to ethyl acetate, and ultrasonic dispersion is performed. Of a carbon-based filler having a solid content concentration of 0.3 mass% by applying vibration with ultrasonic waves having an amplitude of 30 μm for 15 minutes using a machine (trade name “Ultrasonic Disperser for Testing GSD600AT” manufactured by Sonic Technology Co., Ltd.). A dispersion was prepared.
(2) Preparation of solution of adhesive composition For 100 parts by mass (solid content) of adhesive resin of the type shown in Table 1, a dispersion of carbon-based filler prepared in (1) above (the dispersion is a table) 1 was added), and additives of the type and blending amount (solid content ratio) shown in Table 1 were added as necessary. Then, using an “ultra-high speed multi-stirring system lab solution” (trade name, manufactured by Primix Co., Ltd.), the mixture is stirred for 10 minutes at a rotational speed of 2000 rpm, and a solution of an adhesive composition having a solid content concentration of 10 mass% Prepared.
(3) Preparation of conductive pressure-sensitive adhesive sheet A solution of the pressure-sensitive adhesive composition prepared in (2) above was prepared by using a release sheet (product name “SP-PET 381031” manufactured by Lintec Corporation, thickness: 38 μm, surface having a silicone release treatment) The coated film is formed on the surface of the peeled polyethylene terephthalate film) so that the thickness after drying is 20 μm, and the coated film is dried at 90 ° C. for 1 minute to form an adhesive layer. did.
And the 50-micrometer-thick polyethylene terephthalate film (the Toray Industries make, brand name "Lumilar") was bonded together on the said adhesive layer, and the electroconductive adhesive sheet with a base material was produced.
比較例７～８
（１）炭素系フィラーの分散液の調製
　表１に示す種類及び固形分量（粘着性樹脂１００質量部（固形分）に対する固形分比）の炭素系フィラーを酢酸エチル中に添加し、手動によって１５分間撹拌し、固形分濃度０．３質量％の炭素系フィラーの分散液を調製した。
（２）粘着性組成物の溶液の調製
　上記「アクリル系樹脂（２）」１００質量部（固形分）に対し、上記（１）で調製した炭素系フィラーの分散液を２．８６質量部（固形分比）及び上記「架橋剤」を２．１質量部（固形分比）を添加し、手動によって１０分間撹拌し、固形分濃度１０質量％の粘着性組成物の溶液を調製した。
（３）導電性粘着シートの作製
　上述の実施例１と同様にして、基材付き導電性粘着シートを作製した。 Comparative Examples 7-8
(1) Preparation of carbon-based filler dispersion A carbon-based filler of the type and solid content (solid content ratio with respect to 100 parts by mass (adhesive content) of the adhesive resin) shown in Table 1 is added to ethyl acetate, and 15 manually. The mixture was stirred for a minute to prepare a carbon-based filler dispersion having a solid concentration of 0.3% by mass.
(2) Preparation of Adhesive Composition Solution With respect to 100 parts by mass (solid content) of the “acrylic resin (2)”, 2.86 parts by mass of the carbon-based filler dispersion prepared in (1) above ( (Solid content ratio) and 2.1 parts by mass (solid content ratio) of the above-mentioned “crosslinking agent” were added and stirred manually for 10 minutes to prepare a solution of an adhesive composition having a solid content concentration of 10 mass%.
(3) Production of conductive adhesive sheet A conductive adhesive sheet with a substrate was produced in the same manner as in Example 1 described above.
　上記のとおり、実施例及び比較例で作製した導電性粘着シートについて、「粘着剤層中の炭素系フィラーの分散状態」及び「導電性粘着シートの物性値」は、以下の記載の方法により測定した。これらの結果を表１に示す。 As described above, for the conductive pressure-sensitive adhesive sheets prepared in Examples and Comparative Examples, the “dispersed state of the carbon-based filler in the pressure-sensitive adhesive layer” and the “physical property value of the conductive pressure-sensitive adhesive sheet” were measured by the following methods. did. These results are shown in Table 1.
＜炭素系フィラーの占有面積率、分散形状、非ひも状凝集体の含有率＞
　作製した導電性粘着シートの基材側を、反射濃度計（Ｍａｃｂｅｔｈ社製、商品名「Ｍａｃｂｅｔｈ　ＲＤ９１８」）の白色板（ＯＤ値：０．０５）上に載せた後、当該導電性粘着シートの剥離シートを除去し、粘着剤層の貼付表面を表出させた。
　次に、デジタル顕微鏡（株式会社キーエンス製、商品名「デジタルマイクロスコープＶＨＸ－１０００」）を用いて、表出した粘着剤層の貼付表面を平面視し、任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域を、倍率２０００倍で撮影して、デジタル画像を取得した。
　例えば、図５（ａ）は、実施例１の当該デジタル画像であり、図５（ｂ）は、比較例６の当該デジタル画像である。
　なお、粘着剤層中の炭素系フィラーの分散形状については、当該デジタル画像からひも状物が確認できれば「ひも状」とし、ひも状物が確認できず凝集物のみであれば「凝集体」と判断した。
　次に、取得した上記デジタル画像に対して、画像解析ソフト「ＧＩＭＰ　２」（ｈｔｔｐ：／／ｗｗｗ．ｇｉｍｐ．ｏｒｇ／にて入手可能）を用いて、上記領域内のＲＧＢがいずれも２５５の白色箇所を基準とし、閾値９０にて２値化し、全領域に占める当該黒色箇所の割合を算出した。図６及び図７は、実施例１～４及び比較例１～８は取得した上記デジタル画像を２値化した２値化画像である。
　また、上記黒色箇所（炭素系フィラーが占有する箇所）が占める全面積に対する、短径４μｍ以上の非ひも状凝集体の含有率も同時に算出した。 <Occupied area ratio of carbon filler, dispersion shape, content ratio of non-string aggregate>
The substrate side of the produced conductive adhesive sheet was placed on a white plate (OD value: 0.05) of a reflection densitometer (manufactured by Macbeth, trade name “Macbeth RD918”), and then the conductive adhesive sheet The release sheet was removed, and the adhesive surface of the pressure-sensitive adhesive layer was exposed.
Next, using a digital microscope (manufactured by Keyence Co., Ltd., trade name “Digital Microscope VHX-1000”), the sticking surface of the exposed adhesive layer was viewed in plan and arbitrarily selected 10,000 μm 2 (length of one side) A square area having a length of 100 μm was photographed at a magnification of 2000 times to obtain a digital image.
For example, FIG. 5A is the digital image of Example 1, and FIG. 5B is the digital image of Comparative Example 6.
The dispersion shape of the carbon-based filler in the pressure-sensitive adhesive layer is “string” if the string-like material can be confirmed from the digital image, and “aggregate” if the string-like material cannot be confirmed and only the aggregate. It was judged.
Next, using the image analysis software “GIMP 2” (available at http://www.gimp.org/) for the acquired digital image, all the RGB in the region are 255 white. Using the location as a reference, binarization was performed with a threshold 90, and the ratio of the black location in the entire area was calculated. 6 and 7 are binarized images obtained by binarizing the acquired digital images in Examples 1 to 4 and Comparative Examples 1 to 8. FIG.
In addition, the content of non-string aggregates having a minor axis of 4 μm or more with respect to the total area occupied by the black portion (location occupied by the carbon-based filler) was also calculated simultaneously.
＜粘着剤層中の炭素系フィラーの「太さの平均」、「平均アスペクト比」＞
　走査型電子顕微鏡（株式会社日立ハイテクノロジーズ製、製品名「Ｓ－４７００」）を用いて、作製した導電性粘着シートの剥離シートを除去し、表出した粘着剤層の貼付表面を平面視し、任意に選択した１００００μｍ２（一辺の長さが１００μｍである正方形）の領域中に満たれた炭素系フィラーを１０本無作為に抽出した。そして、その無作為に抽出した１０本の炭素系フィラーの太さ及び長さを測定し、その平均値を粘着剤層中に分散している炭素系フィラーの「太さ（ｄ）の平均」及び「長さ（ｘ）の平均」とした。
　また、粘着剤層中に分散している炭素系フィラーの「平均アスペクト比」は、「長さ（ｘ）の平均／太さ（ｄ）の平均」より算出した。 <"Average thickness" and "Average aspect ratio" of the carbon-based filler in the adhesive layer>
Using a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation, product name “S-4700”), the release sheet of the produced conductive pressure-sensitive adhesive sheet was removed, and the sticking surface of the exposed pressure-sensitive adhesive layer was viewed in plan view. Ten carbon-based fillers filled in an arbitrarily selected region of 10,000 μm 2 (a square having a side length of 100 μm) were randomly extracted. Then, the thickness and length of 10 randomly extracted carbon-based fillers are measured, and the average value of the carbon-based fillers dispersed in the adhesive layer is “average thickness (d)”. And “average of length (x)”.
The “average aspect ratio” of the carbon-based filler dispersed in the pressure-sensitive adhesive layer was calculated from “average length (x) / average thickness (d)”.
＜導電性粘着シートの粘着力＞
　作製した導電性粘着シートを５ｍｍ×３００ｍｍの大きさに切断したものを試験片とし、２３℃、５０％ＲＨ（相対湿度）の環境下で、当該試験片の剥離シートを除去し、表出した粘着剤層をステンレス板（ＳＵＳ３０４、３６０番研磨）に貼付し、同環境下で２４時間静置した。
　静置後、ＪＩＳ　Ｚ０２３７：２０００に準拠して、１８０°引き剥がし法により、引っ張り速度３００ｍｍ／分にて試験片をステンレス板から剥離した際の粘着力を測定した。 <Adhesive strength of conductive adhesive sheet>
The produced conductive adhesive sheet was cut into a size of 5 mm × 300 mm as a test piece, and the release sheet of the test piece was removed and exposed in an environment of 23 ° C. and 50% RH (relative humidity). The pressure-sensitive adhesive layer was attached to a stainless steel plate (SUS304, No. 360 polishing) and allowed to stand for 24 hours in the same environment.
After standing, in accordance with JIS Z0237: 2000, the adhesive strength when the test piece was peeled from the stainless steel plate at a pulling speed of 300 mm / min was measured by a 180 ° peeling method.
＜導電性粘着シートの表面抵抗率＞
　ＪＩＳ　Ｋ　７１９４に準拠して測定した。
　具体的には、作製した導電性粘着シートを２０ｍｍ×４０ｍｍの大きさに切断し、２３℃、５０％ＲＨ（相対湿度）の環境下で２４時間静置したものを試験片とし、当該試験片の剥離シートを除去して表出した粘着剤層に対して、低抵抗率計（株式会社三菱化学アナリテック製、製品名「ロレスタＧＰ　ＭＣＰ－Ｔ６１０型」）を用いて、表面抵抗率を測定した。
　上記表面抵抗率の測定は３回行い、表１には、その３回の平均値を記載している。 <Surface resistivity of conductive adhesive sheet>
The measurement was performed according to JIS K 7194.
Specifically, the produced conductive adhesive sheet was cut into a size of 20 mm × 40 mm and allowed to stand for 24 hours in an environment of 23 ° C. and 50% RH (relative humidity). The surface resistivity was measured using a low resistivity meter (product name: “Loresta GP MCP-T610”, manufactured by Mitsubishi Chemical Analytech Co., Ltd.) did.
The surface resistivity was measured three times, and Table 1 shows the average value of the three times.
Figure JPOXMLDOC01-appb-T000010
Figure JPOXMLDOC01-appb-T000010
　実施例１～４で作製した導電性粘着シートは、粘着剤層の貼付表面を平面視した際に、平面視した特定の領域内における炭素系フィラーの占有面積率が所定の範囲内であり、比較例１～８の導電性粘着シートに比べて、表面抵抗率が低いことがわかる。
　図５（ａ）の実施例１のデジタル画像によれば、粘着剤層中において、炭素系フィラーがひも状に分散していることが分かる。なお、実施例２～４の導電性粘着シートが有する粘着剤層中においても、図５（ａ）に示すデジタル画像と同様に、炭素系フィラーがひも状に分散していることが確認された。
　一方、図５（ｂ）の比較例６のデジタル画像によれば、粘着剤層中において、炭素系フィラーが凝集し、ひも状物を有さない非ひも状凝集体を形成して分散している。その結果、粘着剤層の貼付表面を平面視した際の炭素系フィラーの占有面積率の値が小さくなっている。 In the conductive adhesive sheets prepared in Examples 1 to 4, the area ratio of the carbon-based filler in a specific region in plan view is within a predetermined range when the adhesive surface of the adhesive layer is viewed in plan view. It can be seen that the surface resistivity is lower than that of the conductive adhesive sheets of Comparative Examples 1 to 8.
According to the digital image of Example 1 in FIG. 5A, it can be seen that the carbon-based filler is dispersed in a string shape in the pressure-sensitive adhesive layer. In the adhesive layers of the conductive adhesive sheets of Examples 2 to 4, it was confirmed that the carbon-based filler was dispersed in the form of a string, as in the digital image shown in FIG. 5 (a). .
On the other hand, according to the digital image of Comparative Example 6 in FIG. 5B, the carbon-based filler aggregates in the pressure-sensitive adhesive layer to form a non-string-like aggregate having no string-like material and dispersed. Yes. As a result, the value of the occupied area ratio of the carbon-based filler when the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan is small.
　本発明の導電性粘着シートは、良好な粘着力を有すると共に、表面抵抗率が低いため、帯電防止性及び導電性に優れる。
　そのため、本発明の導電性粘着シートは、例えば、コンピューター、通信機器等の電子機器を収納する容器の電磁遮蔽材、電気部品等の接地線、更には摩擦電気等の静電気から生ずる火花による発火防止材等の部材に用いられる接合部材として好適である。 The conductive pressure-sensitive adhesive sheet of the present invention is excellent in antistatic property and conductivity because of having good adhesive force and low surface resistivity.
Therefore, the conductive pressure-sensitive adhesive sheet of the present invention prevents, for example, ignition due to sparks generated from static electricity such as electromagnetic shielding materials for containers for storing electronic devices such as computers and communication devices, grounding wires for electrical components, and even triboelectricity. It is suitable as a joining member used for members such as materials.
１ａ、１ｂ、１ｃ、１ｄ　　導電性粘着シート
１１、１１’　　粘着剤層
１１ａ　　貼付表面
１２　　基材
１３、１３’　　剥離シート
１５、１５１、１５２　　炭素系フィラー（Ｂ）
１５ａ、１５ｂ、１５ｃ、１５ｄ　　ひも形状部分
２１、２２　　凝集体 1a, 1b, 1c, 1d Conductive adhesive sheet 11, 11 'Adhesive layer 11a Affixing surface 12 Base material 13, 13' Release sheet 15, 151, 152 Carbon-based filler (B)
15a, 15b, 15c, 15d String-shaped portions 21, 22 Aggregates

Claims (11)

  1. 　粘着性樹脂（Ａ）及び炭素系フィラー（Ｂ）を含む粘着剤層を有する導電性粘着シートであって、
    　前記粘着剤層中の炭素系フィラー（Ｂ）の含有量が、前記粘着剤層の全質量に対して、０．０１～２０質量％であり、
    　前記粘着剤層の貼付表面を平面視した際に、当該貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）の占有面積率が１７％以上である、導電性粘着シート。     A conductive adhesive sheet having an adhesive layer containing an adhesive resin (A) and a carbon-based filler (B),
    The content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.01 to 20% by mass with respect to the total mass of the pressure-sensitive adhesive layer;
    A conductive pressure-sensitive adhesive sheet, wherein when the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan, the occupation area ratio of the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface is 17% or more.
  2. 　前記粘着剤層が、超音波による振動を与えて調製された、炭素系フィラー（ｂ）の分散液に、粘着性樹脂（Ａ）を配合した後、撹拌機を用いた撹拌により調製された粘着性組成物から形成された層である、請求項１に記載の導電性粘着シート。 The pressure-sensitive adhesive layer was prepared by applying ultrasonic vibration and mixing the adhesive resin (A) with a dispersion of the carbon-based filler (b), and then preparing the pressure-sensitive adhesive prepared by stirring using a stirrer. The conductive adhesive sheet according to claim 1, which is a layer formed from a conductive composition.
  3. 　前記粘着剤層中において、炭素系フィラー（Ｂ）がひも状に分散しており、
    　前記粘着剤層中をひも状に分散している炭素系フィラー（Ｂ）の太さの平均が０．５～５．０μｍであり、且つ平均アスペクト比が３．０以上である、請求項１又は２に記載の導電性粘着シート。     In the pressure-sensitive adhesive layer, the carbon-based filler (B) is dispersed in a string shape,
    The average thickness of the carbon-based filler (B) dispersed in a string in the pressure-sensitive adhesive layer is 0.5 to 5.0 µm, and the average aspect ratio is 3.0 or more. Or the electroconductive adhesive sheet of 2.
  4. 　前記粘着剤層の貼付表面を平面視した際に、当該貼付表面上の任意に選択した領域中の炭素系フィラー（Ｂ）が占める全占有面積に対する、炭素系フィラー（Ｂ）が凝集してなる短径４μｍ以上の非ひも状凝集体の含有率が５０％以下である、請求項１～３のいずれか１項に記載の導電性粘着シート。 When the adhesive surface of the pressure-sensitive adhesive layer is viewed in plan, the carbon-based filler (B) is aggregated with respect to the total occupied area occupied by the carbon-based filler (B) in an arbitrarily selected region on the adhesive surface. The conductive pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the content of non-string aggregates having a minor axis of 4 µm or more is 50% or less.
  5. 　炭素系フィラー（Ｂ）が、カーボンナノ材料である、請求項１～４のいずれか１項に記載の導電性粘着シート。 The conductive adhesive sheet according to any one of claims 1 to 4, wherein the carbon-based filler (B) is a carbon nanomaterial.
  6. 　粘着性樹脂（Ａ）が、アクリル系樹脂及びウレタン系樹脂からなる群より選ばれる１種以上の粘着性樹脂を含む、請求項１～５のいずれか１項に記載の導電性粘着シート。 The conductive adhesive sheet according to any one of claims 1 to 5, wherein the adhesive resin (A) comprises one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins.
  7. 　前記粘着剤層中の炭素系フィラー（Ｂ）の含有量が、前記粘着剤層の全質量に対して、０．１～７質量％である、請求項１～６のいずれか１項に記載の導電性粘着シート。 7. The content of the carbon-based filler (B) in the pressure-sensitive adhesive layer is 0.1 to 7% by mass with respect to the total mass of the pressure-sensitive adhesive layer. Conductive adhesive sheet.
  8. 　表面抵抗率が１．０×１０１０Ω／□以下である、請求項１～７のいずれか１項に記載の導電性粘着シート。 The conductive adhesive sheet according to any one of claims 1 to 7, wherein the surface resistivity is 1.0 × 10 10 Ω / □ or less.
  9. 　粘着力が５．０Ｎ／２５ｍｍ以上である、請求項１～８のいずれか１項に記載の導電性粘着シート。 The conductive adhesive sheet according to any one of claims 1 to 8, wherein the adhesive strength is 5.0 N / 25 mm or more.
  10. 　請求項１～９のいずれか１項に記載の導電性粘着シートを製造する方法であって、
    　下記工程（１）～（３）を有する、導電性粘着シートの製造方法。
    工程（１）：超音波による振動を与えて、炭素系フィラー（ｂ）の分散液を調製する工程
    工程（２）：工程（１）で得た分散液に、粘着性樹脂（Ａ）を配合し、撹拌翼を有する撹拌機を用いた撹拌により粘着性組成物を調製する工程
    工程（３）：工程（２）で得た粘着性組成物を用いて粘着剤層を形成する工程     A method for producing the conductive pressure-sensitive adhesive sheet according to any one of claims 1 to 9,
    A method for producing a conductive pressure-sensitive adhesive sheet, comprising the following steps (1) to (3).
    Step (1): Applying ultrasonic vibration to prepare a carbon-based filler (b) dispersion Step (2): Blending the adhesive resin (A) into the dispersion obtained in Step (1) Step (3) of preparing a pressure-sensitive adhesive composition by stirring using a stirrer having a stirring blade: Step of forming a pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition obtained in step (2)
  11. 　工程（２）において、前記撹拌機が有する撹拌翼の回転数が５００～１００００ｒｐｍである、請求項１０の記載の導電性粘着シートの製造方法。 The method for producing a conductive pressure-sensitive adhesive sheet according to claim 10, wherein, in the step (2), the rotation speed of the stirring blade of the stirrer is 500 to 10,000 rpm.
PCT/JP2015/059735 2014-09-30 2015-03-27 Electroconductive pressure-sensitive adhesive sheet WO2016051829A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2016551566A JPWO2016051829A1 (en) 2014-09-30 2015-03-27 Conductive adhesive sheet

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014-200395 2014-09-30
JP2014200395 2014-09-30

Publications (1)

Publication Number Publication Date
WO2016051829A1 true WO2016051829A1 (en) 2016-04-07

Family

ID=55629888

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/059735 WO2016051829A1 (en) 2014-09-30 2015-03-27 Electroconductive pressure-sensitive adhesive sheet

Country Status (2)

Country Link
JP (1) JPWO2016051829A1 (en)
WO (1) WO2016051829A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109021859A (en) * 2018-06-22 2018-12-18 北京无线电计量测试研究所 A kind of stirring means of conducting resinl

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007308158A (en) * 2006-05-17 2007-11-29 Sumitomo Bakelite Co Ltd Cover tape for electronic component package
JP2008288189A (en) * 2007-05-18 2008-11-27 Korea Electrotechnology Research Inst Method of forming transparent conductive film containing carbon nanotube and binder, and transparent conductive film formed thereby
JP2010163586A (en) * 2008-03-04 2010-07-29 Lintec Corp Adhesive composition and adhesive sheet
JP2010163587A (en) * 2008-03-04 2010-07-29 Lintec Corp Adhesive composition and adhesive sheet
JP2011236327A (en) * 2010-05-10 2011-11-24 Shinshu Univ Method for producing compound adhesive, compound adhesive and adhesive sheet
JP2012087041A (en) * 2010-09-22 2012-05-10 Yamagata Prefecture Multi-wall carbon nanotube-dispersed and mixed aqueous gel, manufacturing method, and application thereof
JP2012144624A (en) * 2011-01-11 2012-08-02 Shinshu Univ Process for producing composite adhesive, composite adhesive, and adhesive sheet
WO2014007353A1 (en) * 2012-07-05 2014-01-09 リンテック株式会社 Pressure-sensitive adhesive sheet

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007308158A (en) * 2006-05-17 2007-11-29 Sumitomo Bakelite Co Ltd Cover tape for electronic component package
JP2008288189A (en) * 2007-05-18 2008-11-27 Korea Electrotechnology Research Inst Method of forming transparent conductive film containing carbon nanotube and binder, and transparent conductive film formed thereby
JP2010163586A (en) * 2008-03-04 2010-07-29 Lintec Corp Adhesive composition and adhesive sheet
JP2010163587A (en) * 2008-03-04 2010-07-29 Lintec Corp Adhesive composition and adhesive sheet
JP2011236327A (en) * 2010-05-10 2011-11-24 Shinshu Univ Method for producing compound adhesive, compound adhesive and adhesive sheet
JP2012087041A (en) * 2010-09-22 2012-05-10 Yamagata Prefecture Multi-wall carbon nanotube-dispersed and mixed aqueous gel, manufacturing method, and application thereof
JP2012144624A (en) * 2011-01-11 2012-08-02 Shinshu Univ Process for producing composite adhesive, composite adhesive, and adhesive sheet
WO2014007353A1 (en) * 2012-07-05 2014-01-09 リンテック株式会社 Pressure-sensitive adhesive sheet

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
SHO OTAKA ET AL.: "Dodensei Carbon o Donyu shita Nenchakusei Jushi no Dodensei to Bunsansei", THE ADHESION SOCIETY OF JAPAN NENJI TAIKAI KOEN YOSHISHU, vol. 51, 2013, pages 37 - 38 *
SHO OTAKA ET AL.: "Influence of Surface Free Energy of Polymer on Dispersibility of Multi- walled Carbon Nanotube and Conductivity of Carbon/Polymer Composites", JOURNAL OF THE ADHESION SOCIETY OF JAPAN, vol. 50, no. 4, 2014, pages 115 - 122, [retrieved on 20140401] *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109021859A (en) * 2018-06-22 2018-12-18 北京无线电计量测试研究所 A kind of stirring means of conducting resinl
CN109021859B (en) * 2018-06-22 2021-04-02 北京无线电计量测试研究所 Stirring method of conductive adhesive

Also Published As

Publication number Publication date
JPWO2016051829A1 (en) 2017-07-13

Similar Documents

Publication Publication Date Title
KR102388869B1 (en) Conductive adhesive sheet
JP6270721B2 (en) Adhesive sheet
WO2009041674A1 (en) Electroconductive pressure-sensitive adhesive tape
JP7059873B2 (en) Conductive compositions, and conductive films
TWI740935B (en) Adhesive sheet
JP2017132874A (en) Earth label for adhering electronic component
WO2016051829A1 (en) Electroconductive pressure-sensitive adhesive sheet
KR102390524B1 (en) Conductive adhesive sheet
KR102389424B1 (en) Conductive adhesive sheet
CN108300371A (en) Conductive pressure sensitive adhesive tape
TWI673337B (en) Conductive adhesive sheet
JP6204189B2 (en) Adhesive composition and conductive adhesive sheet
WO2015098965A1 (en) Adhesive composition, adhesive sheet, and method for processing adhesive sheet
JP6470944B2 (en) Conductive adhesive composition and conductive adhesive sheet

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15845679

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2016551566

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15845679

Country of ref document: EP

Kind code of ref document: A1