JP6500905B2 - Conductive adhesive sheet - Google Patents

Description

  The present invention relates to a conductive pressure-sensitive adhesive sheet.

  In the past, simple bonding was used in various joints such as electromagnetic shielding materials for containers that contain electronic devices such as computers and communication devices, grounding wires for electrical components, and fire prevention materials due to sparks generated by static electricity such as triboelectricity. Conductive adhesive sheet is used.

  The pressure-sensitive adhesive composition used in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet is a conductive material such as a metal powder such as copper powder, silver powder, nickel powder, or aluminum powder in order to impart antistatic properties and conductivity. Are dispersed in a tacky resin.

  For example, Patent Document 1 discloses a conductive pressure-sensitive adhesive in which at least one of a carbon nanotube and a carbon micro coil is dispersed in a pressure-sensitive adhesive as a conductive substance, and a conductive pressure-sensitive adhesive sheet using the conductive pressure-sensitive adhesive ing.

JP 2001-172582 A

By the way, in order to improve the conductivity of the pressure-sensitive adhesive layer of the above-mentioned conductive pressure-sensitive adhesive sheet, a large amount of a conductive substance is compounded in the pressure-sensitive adhesive composition which is a forming material of the pressure-sensitive adhesive layer. The particles need to be in close contact with each other.
However, when a large amount of a conductive substance is blended in the pressure-sensitive adhesive composition, the adhesion of the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition tends to decrease. On the other hand, if the content of the conductive substance in the pressure-sensitive adhesive layer is reduced to enhance the adhesive strength, there is a trade-off problem that the conductivity of the pressure-sensitive adhesive layer is reduced.
The conductive pressure-sensitive adhesive sheet disclosed in Patent Document 1 is still insufficient in terms of improving both the adhesive strength and the conductivity.

  An object of the present invention is to provide a conductive pressure-sensitive adhesive sheet having excellent adhesion and having excellent antistatic properties and conductivity.

The present inventors are configured to have at least a tacky conductive layer and a non-tacky conductive layer, and further, the surface resistivity of each of the sticky conductive layer and the non-tacky conductive layer alone, and the surface resistivity of the two layers. The conductive adhesive sheet which adjusted the ratio of to the predetermined | prescribed range discovers that the said subject can be solved, and completed this invention.
That is, the present invention provides the following [1] to [16].
[1] A conductive pressure-sensitive adhesive sheet having at least a tacky conductive layer (X) and a non-tacky conductive layer (Y),
The surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is 1.0 × 10 ^{2 to} 1.0 × 10 ¹⁰ Ω / □,
The surface resistivity (ρ _SY ) of the non-adhesive conductive layer (Y) alone is 1.0 × 10 ^{−2 to} 1.0 × 10 ⁸ Ω / □, and
Equation (1): 0 <satisfies the _{log 10 (ρ SX / ρ SY} ) ≦ 6.0, the conductive adhesive sheet.
[2] The conductive pressure-sensitive adhesive sheet according to the above [1], wherein the thickness (t _x ) of the adhesive conductive layer (X) is 1 to 1200 μm.
[3] The conductive pressure-sensitive adhesive sheet according to the above [1] or [2], wherein the thickness (t _Y ) of the non-adhesive conductive layer (Y) is 0.01 to 200 μm.
[4] Any one of the above-mentioned [1] to [3], wherein the adhesive conductive layer (X) is a layer formed from an adhesive composition containing an adhesive resin (x1) and a carbon-based filler (x2) The electroconductive adhesive sheet as described in 1.
[5] The adhesive resin (x1) contained in the adhesive composition is selected from the group consisting of acrylic resins, urethane resins, rubber resins, styrene resins, polyester resins, and polyolefin resins. The electroconductive adhesive sheet as described in said [4] containing 1 or more types of adhesive resin.
[6] The conductive pressure-sensitive adhesive sheet according to the above [4] or [5], wherein the average aspect ratio of the carbon-based filler (x2) contained in the adhesive composition is 1.5 or more.
[7] The above [4], wherein the content of the carbon-based filler (x2) contained in the adhesive composition is 0.01 to 15 parts by mass with respect to 100 parts by mass of the adhesive resin (x1) The electroconductive adhesive sheet of any one of-[6].
[8] The conductive pressure-sensitive adhesive sheet according to any one of the above [4] to [7], wherein the carbon-based filler (x2) contained in the pressure-sensitive adhesive composition is a carbon nanomaterial.
[9] The non-adhesive conductive layer (Y) is a layer containing one or more conductive materials selected from the group consisting of a conductive polymer, a carbon-based filler, and a metal oxide; The electroconductive adhesive sheet of any one of 8].
[10] The non-adhesive conductive layer (Y) is a layer containing one or more conductive materials selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials, and ITO (indium tin oxide), The electroconductive adhesive sheet of any one of 1]-[9].
[11] The conductive pressure-sensitive adhesive sheet according to the above [9] or [10], wherein the density of the conductive material contained in the non-adhesive conductive layer (Y) is 0.8 to 2.5 g / cm ³ .
[12] The conductive material according to any one of the above [1] to [11], which has a structure in which a substrate, a non-adhesive conductive layer (Y), and a sticky conductive layer (X) are laminated in this order. Adhesive sheet.
[13] The conductive pressure-sensitive adhesive sheet according to the above [12], which has a two-layered body composed of the non-adhesive conductive layer (Y) and the adhesive conductive layer (X) on both sides of the substrate.
[14] The conductive pressure-sensitive adhesive sheet according to the above [12] or [13], wherein the substrate is an insulating substrate having a surface resistivity of 1.0 × 10 ¹⁴ Ω / □ or more.
[15] Any one of the above [1] to [11], which has a configuration in which a two-layered body composed of an adhesive conductive layer (X) and a non-adhesive conductive layer (Y) is sandwiched by two release sheets. The electroconductive adhesive sheet as described in 1.
[16] Two three-layer bodies in which the first adhesive conductive layer (X-I), the non-adhesive conductive layer (Y), and the second adhesive conductive layer (X-II) are laminated in this order The electroconductive adhesive sheet of any one of said [1]-[11] which has the structure clamped by the peeling sheet of this.

  The conductive pressure-sensitive adhesive sheet of the present invention has good adhesive strength and is excellent in antistatic properties and conductivity.

It is a sectional view of a substrate-attached conductive pressure-sensitive adhesive sheet, which is a configuration of a preferred embodiment of the conductive pressure-sensitive adhesive sheet of the present invention. It is sectional drawing of a substrate-free electroconductive adhesive sheet which is a structure of the suitable one aspect | mode of the electroconductive adhesive sheet of this invention.

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, it is measured based on the method described in the examples. Value.
Also, for example, "(meth) acrylate" is used as a term indicating both "acrylate" and "methacrylate", and the same applies to other similar terms.
Furthermore, unless otherwise indicated, "the surface resistivity of a conductive adhesive sheet" means the surface resistivity measured from the surface side of the adhesive conductive layer (X) which a conductive adhesive sheet has.

  In the present invention, the surface resistivity and volume resistivity of each layer are values measured in accordance with JIS K 7194, and specifically mean values measured by the method described in the examples. Do.

[Conductive adhesive sheet]
The conductive pressure-sensitive adhesive sheet of the present invention has at least a tacky conductive layer (X) and a non-tacky conductive layer (Y).
In the conductive pressure-sensitive adhesive sheet of the present invention, the surface resistivity of the adhesive conductive layer (X) is significantly reduced by providing the non-adhesive conductive layer (Y), and the antistatic property and the conductivity are improved. it can. As a result, since it is not necessary to contain a large amount of carbon-based fillers in the adhesive conductive layer (X), the conductive adhesive sheet of the present invention has a good adhesive force.

In the present invention, the “adhesive conductive layer (X)” and the “non-adhesive conductive layer (Y)” are distinguished by the presence or absence of adhesiveness, and the presence or absence of the adhesiveness is the probe tack to the surface of each conductive layer. Judge from the peak top value.
That is, in the present invention, if the value of the peak top of the probe tack to the surface of the target conductive layer is 0.1 N or more, it is judged that the conductive layer has adhesiveness, and “adhesive conductivity” It is classified into "layer (X)".
Conversely, if the peak top value of the probe tack to the surface of the target conductive layer is less than 0.1 N, the conductive layer is judged to be non-adhesive, and the “non-adhesive conductive layer (Y) "are categorized.
In addition, the value of the peak top of the probe tack with respect to the surface of the object conductive layer is a value measured according to JIS Z 0237 (1991), and specifically, it is described by the method described in the examples described later. It means the measured value.

The conductive pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it has a structure having at least a tacky conductive layer (X) and a non-tacky conductive layer (Y), and may have other layers other than these. .
In addition, the conductive pressure-sensitive adhesive sheet according to one aspect of the present invention may have a configuration in which another layer is provided between the adhesive conductive layer (X) and the non-adhesive conductive layer (Y). The adhesive conductive layer (X) and the non-adhesive conductive layer (Y) are preferably directly laminated from the viewpoint of lowering the surface resistivity of the adhesive sheet and improving the antistatic property and the conductivity.

FIG. 1 is a cross-sectional view of a conductive pressure-sensitive adhesive sheet with a substrate, which is a configuration of a preferred embodiment of the conductive pressure-sensitive adhesive sheet of the present invention.
Examples of the conductive adhesive sheet according to one embodiment of the present invention include a substrate 13, a non-adhesive conductive layer (Y) 12 and an adhesive conductive layer (X) 11 as shown in FIG. 1 (a). The electroconductive adhesive sheet 1A which has the structure laminated | stacked in order is mentioned. This conductive pressure-sensitive adhesive sheet 1A has a two-layered body 21 composed of a non-adhesive conductive layer (Y) 12 and a tacky conductive layer (X) 11 on one surface of a substrate.
Moreover, it is good also as electroconductive adhesive sheet 1B as shown in FIG.1 (b) which laminated | stacked the peeling sheet 14 further on adhesive conductive layer (X) 11 with respect to the structure of the electroconductive adhesive sheet 1A.

In addition, as the conductive adhesive sheet according to one aspect of the present invention, for example, a non-adhesive conductive layer (Y) and an adhesive conductive layer on both sides of a substrate as shown in FIGS. 1 (c) and 1 (d) The electroconductive adhesive sheet which has 2 layer body 21a, 21b each comprised from layer (X) may be sufficient.
That is, the conductive pressure-sensitive adhesive sheet 2A shown in FIG. 1 (c) has the first non-adhesive conductive layer (Y-I) 12a and the first adhesive conductive layer (X) on one surface of the substrate 13. -I) has a first bilayer body 21a composed of 11a, and on the other surface of the substrate 13, a second non-adhesive conductive layer (Y-II) 12b and a second adhesive conductive layer It has the 2nd two-layer body 21b comprised from layer (X-II) 11b.
The conductive adhesive sheet 2B shown in FIG. 1 (d) is the first adhesive conductive layer (X-I) 11a and the second adhesive conductive layer in addition to the configuration of the conductive adhesive sheet 2A. (X-II) It has the structure which laminated | stacked peeling sheet 14a, 14b, respectively on 11b.

Moreover, FIG. 2 is sectional drawing of a base-material-free electroconductive adhesive sheet which is a structure of the suitable one aspect | mode of the electroconductive adhesive sheet of this invention.
The conductive pressure-sensitive adhesive sheet according to one aspect of the present invention may be a substrate-free conductive pressure-sensitive adhesive sheet, and specifically, a pressure-sensitive adhesive conductive layer (X) 11 and a conductive conductive layer (X) as shown in FIG. The electroconductive adhesive sheet 3 which has the structure which clamped the two-layer body 21 comprised from the non-adhesive conductive layer (Y) 12 by two peeling sheet 14a, 14b is mentioned.
Moreover, as the electroconductive adhesive sheet of 1 aspect of this invention, as shown in FIG.2 (b), 1st adhesive conductive layer (XI), the non-adhesive conductive layer (Y) 12, and The conductive adhesive sheet 4 may have a configuration in which a three-layer body 22 in which the second adhesive conductive layer (X-II) 11b is laminated in this order is sandwiched between two release sheets 14a and 14b.
The conductive pressure-sensitive adhesive sheet according to one aspect of the present invention having a configuration other than the above is constituted of a pressure-sensitive conductive layer (X) and a non-sticky conductive layer (Y) on one side of a release sheet on which both surfaces have been release-treated. An electroconductive adhesive sheet etc. which have the structure which wound what was provided so that adhesive conductive layer (X) may be rolled in roll shape may be mentioned.

The first adhesive conductive layer (X-I) 11a and the second adhesive conductive layer (X-II) 11b described above may be layers formed of the same adhesive composition, and they have different adhesive properties. It may be a layer formed from the composition.
In addition, the first non-adhesive conductive layer (Y-I) 12a and the second non-adhesive conductive layer (Y-II) 12b may be layers formed of the same material, similarly. It may be a layer formed of different forming materials.
In the present invention, the configurations of the first adhesive conductive layer (X-I) and the second adhesive conductive layer (X-II) are the same as those of the adhesive conductive layer (X), and the first adhesive conductive layer (X-I) and the second adhesive conductive layer (X-II) are the same. The configuration of the non-adhesive conductive layer (Y-I) and the second non-adhesive conductive layer (Y-II) is the same as the non-adhesive conductive layer (Y).

The adhesive conductive layer (X) has adhesiveness (the peak top value of the above-mentioned probe tack is 0.1 N or more), and conductivity (the volume resistivity (ρ _{Vx of the} layer alone) is 1.0 × 10 ⁸ Ω · cm or less) is a layer having a.
On the other hand, the non-adhesive conductive layer (Y) is a layer which is non-tacky (peak top value of the above-mentioned probe tack is less than 0.1 N) and conductive (the volume resistivity of the layer alone (( _VY ) is a layer having 1.0 × 10 ⁸ Ω · cm or less.

In the present invention, the surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is 1.0 × 10 ^{2 to} 1.0 × 10 ¹⁰ Ω / □, preferably 1.0 × 10 ² to 10 1.0 × 10 ⁸ Ω / □, more preferably ^{1.0 × 10 2 ~1.0 × 10 7} Ω / □, more preferably ^{1.0 × 10 2 ~1.0 × 10 6} Ω / □ in is there.
In order to make the surface resistivity (ρ _SX ) less than 1.0 × 10 ² Ω / □, it is necessary to contain a large amount of a conductive substance, so the adhesion of the adhesive conductive layer (X) is lowered. It is easy to do, and it is not preferable in economical aspect.
On the other hand, when the surface resistivity (ρ _SX ) exceeds 1.0 × 10 ¹⁰ Ω / □, even if the non-adhesive conductive layer (Y) is provided, the effect of reducing the surface resistivity of the conductive adhesive sheet is exhibited. It is difficult to do it.

Moreover, the surface resistivity () _SY ) of the non-adhesive conductive layer (Y) alone is 1.0 × 10 ^{−2 to} 1.0 × 10 ⁸ Ω / □, preferably 1.0 × 10 ^−2. ~1.0 × 10 ⁷ Ω / □, more preferably ^{1.0 × 10 -2 ~1.0 × 10 6} Ω / □, more preferably ^{1.0 × 10 -2 ~1.0 × 10 5} Ω It is more preferably 1.0 × 10 ^{−2 to} 1.0 × 10 ⁴ Ω / □, still more preferably 1.0 × 10 ^{−2 to} 1.0 × 10 ³ Ω / □.
Even if a non-adhesive conductive layer (Y) having a surface resistivity (ρ _SY ) of less than 1.0 × 10 ⁻² Ω / □ or more than 1.0 × 10 ⁸ Ω / □ is provided, the conductive adhesive sheet It is difficult to express the effect of reducing the surface resistivity.

Furthermore, in the present invention, the surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone and the surface resistivity (ρ _SY ) of the non-adhesive conductive layer (Y) alone are as follows: It is necessary to satisfy the equation (1) of
Expression (1): 0 <log ₁₀ (ρ _SX / ρ _SY ) ≦ 6.0
When the value of the above log ₁₀ (ρ _SX / ρ _SY ) exceeds 6.0, the surface resistivity of the conductive pressure-sensitive adhesive sheet is not sufficiently lowered, and the antistatic property and the conductivity tend to be inferior.
From the above viewpoint, the value of log ₁₀ (ρ _SX / ρ _SY ) is preferably 5.0 or less, more preferably 4.5 or less, still more preferably 4.0 or less, still more preferably 3.7 or less is there.
On the other hand, the value of log ₁₀ (ρ _SX / ρ _SY ) needs to be a value larger than 0, as in the above-mentioned equation (1).
That is, in the present invention, from the viewpoint of effectively reducing the surface resistivity of the conductive adhesive sheet, the surface resistivity (ρ _SY ) of the non-adhesive conductive layer (Y) alone is the adhesive conductive layer (X) alone. It is a value smaller than the surface resistivity () _SX ) of

The volume resistivity (ρ _Vx ) of the adhesive conductive layer (X) alone is preferably 1.0 × from the viewpoint of forming a conductive adhesive sheet having a good adhesive force and effectively reducing the surface resistivity. ^{10 0 ~1.0 × 10 8 Ω ·} cm, more preferably ^{1.0 × 10 0 ~1.0 × 10 6} Ω · cm, more preferably ^{1.0 × 10 0 ~1.0 × 10 5} Ω Cm, still more preferably 1.0 × 10 ^{0 to} 1.0 × 10 ⁴ Ω · cm.

The volume resistivity (ρ _VY ) of the non-adhesive conductive layer (Y) alone is preferably 1.0 × 10 ⁻⁴ to 1 as a conductive pressure-sensitive adhesive sheet in which the surface resistivity is effectively reduced. .0 × 10 ⁶ Ω · cm, more preferably ^{1.0 × 10 -4 ~1.0 × 10 4} Ω · cm, more preferably ^{1.0 × 10 -4 ~1.0 × 10 3} Ω · cm , More preferably 1.0 × 10 ^{−4 to} 1.0 × 10 ² Ω · cm, further preferably 1.0 × 10 ^{−4 to} 1.0 × 10 ¹ Ω · cm, still more preferably 1.0 × 10 ^{-4 to} 1.0 × 10 ⁰ Ω · cm.
In one aspect of the present invention, from the viewpoint of effectively reducing the surface resistivity of the conductive adhesive sheet, the volume resistivity (、 _VY ) of the non-adhesive conductive layer (Y) alone is a tacky conductive layer ( X) It is preferable that the value is smaller than the volume resistivity (ρ _Vx ) alone.

The thickness (t _x ) of the adhesive conductive layer (X) is appropriately adjusted according to the application etc., but is preferably 1 to 1200 μm, more preferably 2 to 600 μm, more preferably 3 to 300 μm, still more preferably It is 5 to 250 μm, more preferably 10 to 200 μm, and still more preferably 15 to 150 μm.
When the thickness (t _x ) is 1 μm or more, good adhesion can be exhibited regardless of the type of adherend. On the other hand, if the thickness (t _x ) is 1200 μm or less, the conductivity of the obtained conductive adhesive sheet is good. In addition, when the conductive pressure-sensitive adhesive sheet is used as a wound body, winding deviation due to deformation of the adhesive conductive layer (X) or an adverse effect that the adhesive conductive layer (X) protrudes from the end of the wound body. Can be suppressed.

The thickness (t _Y ) of the non-adhesive conductive layer (Y) is appropriately adjusted according to the application etc., but preferably 0.01 to 200 μm, more preferably 0.1 to 160 μm, still more preferably 0. It is 5 to 130 μm, more preferably 1.0 to 100 μm.
If the thickness (t _Y ) is 0.01 μm or more, the surface resistivity of the non-adhesive conductive layer (Y) can be effectively reduced.
On the other hand, when the thickness (t _Y ) is 200 μm or less, when the conductive pressure-sensitive adhesive sheet is wound, winding deviation due to deformation of the non-adhesive conductive layer (Y), the end of the wound body The adverse effect that the non-adhesive conductive layer (Y) protrudes from the part can be suppressed. In addition, by reducing the total thickness of the conductive pressure-sensitive adhesive sheet, the conductive pressure-sensitive adhesive sheet can be easily applied to a small-sized electronic device.

[Forming material of adhesive conductive layer (X)]
The adhesive conductive layer (X) is preferably a layer formed from an adhesive composition containing an adhesive resin (x1) and a carbon-based filler (x2).
In addition, the said adhesive composition may contain a crosslinking agent, a tackifier, and a general purpose additive other than these according to the kind of adhesive resin (x1).
Hereinafter, each component contained in the said adhesive composition is demonstrated.

<Adhesive resin (x1)>
The adhesive resin (x1) contained in the adhesive composition which is a forming material of the adhesive conductive layer (X) means a resin having a mass average molecular weight of 10,000 or more and adhesiveness.
The mass average molecular weight (Mw) of the adhesive resin (x1) is preferably 10,000 to 2,000,000, more preferably 20,000 to 1,500,000, from the viewpoint of improving the adhesive strength of the conductive adhesive sheet.

  The content of the adhesive resin (x1) in the adhesive composition is preferably 60.0 to 99.99 mass%, more preferably 70. 0 to the total amount (100 mass%) of the adhesive composition. It is 0-99.9 mass%, More preferably, it is 80.0-99.5 mass%, More preferably, it is 90.0-99.0 mass%.

  As the adhesive resin (x1), an acrylic resin, a urethane resin, a polyisobutylene resin, a styrene resin, from the viewpoint of improving the adhesive force of the conductive adhesive sheet to make the antistatic property and the conductivity good. It is preferable to include one or more adhesive resins selected from the group consisting of polyester resins and polyolefin resins, and it is selected from the group consisting of acrylic resins, urethane resins, polyisobutylene resins, and styrene resins. It is more preferable to include one or more adhesive resins, and it is further preferable to include one or more adhesive resins selected from the group consisting of acrylic resins and urethane resins.

(Acrylic resin)
As acrylic resin which can be used as adhesive resin (x1), the polymer which has a structural unit derived from the alkyl (meth) acrylate which has a linear or branched alkyl group, for example, (meth) acrylate which has a cyclic structure And polymers having a structural unit derived from
The mass average molecular weight (Mw) of the acrylic resin is preferably 50,000 to 1,500,000, more preferably 150,000 to 1,300,000, further preferably 250,000 to 1,100,000, still more preferably 350,000 to 900,000. .

Among the acrylic resins, a structural unit (a1) derived from an alkyl (meth) acrylate (a1 ′) having an alkyl group having 1 to 20 carbon atoms (hereinafter also referred to as “monomer (a1 ′)”), and a functional group The acrylic copolymer which has a structural unit (a2) derived from a containing monomer (a2 ') (Hereafter, it is also called "monomer (a2')") is preferable.
The acrylic copolymer may have a structural unit (a3) derived from another monomer (a3 ′) other than the monomers (a1 ′) and (a2 ′).
Moreover, the form of copolymerization of the said acryl-type copolymer is not specifically limited. That is, as the said acryl-type copolymer, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient.

As carbon number of the alkyl group which a monomer (a1 ') has, from a viewpoint of an adhesive property improvement, Preferably it is 1-12, More preferably, it is 4-8, More preferably, it is 4-6.
As the monomer (a1 ′), for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tridecyl ( Meta) acrylate, stearyl (meth) acrylate, etc. are mentioned.
Among these monomers (a1 ′), 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, still more preferably, relative to all the structural units (100% by mass) of the above-mentioned acrylic copolymer. Is 70 to 97% by mass, still more preferably 80 to 95% by mass.

Examples of the monomer (a2 ′) include hydroxy group-containing monomers, carboxy group-containing monomers, epoxy group-containing monomers, amino group-containing monomers, cyano group-containing monomers, keto group-containing monomers, alkoxysilyl group-containing monomers, etc. .
Among these monomers (a2 ′), carboxy group-containing monomers are preferred.
Examples of carboxy group-containing monomers include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid and the like, with (meth) acrylic acid being preferred.

  The content of the structural unit (a2) is preferably 0.5 to 50% by mass, more preferably 1 to 40% by mass, still more preferably, relative to the total structural units (100% by mass) of the above-mentioned acrylic copolymer. Is 5 to 30% by mass, more preferably 7 to 20% by mass.

  As a monomer (a3 ′), for example, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl oxyethyl Examples thereof include (meth) acrylates having a cyclic structure such as (meth) acrylate and imide (meth) acrylate, vinyl acetate, acrylonitrile and styrene.

  The content of the structural unit (a3) is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, still more preferably 0 to 100% by mass with respect to all the structural units (100% by mass) of the acrylic copolymer. It is 10% by mass, more preferably 0 to 5% by mass.

  The above-mentioned monomers (a1 ') to (a3') may be used alone or in combination of two or more.

(Urethane resin)
The urethane-based resin that can be used as the adhesive resin (x1) is not particularly limited as long as it is a polymer having at least one of a urethane bond and a urea bond in the main chain and / or side chains. Urethane prepolymer (α) obtained by reacting an isocyanate compound with a monovalent isocyanate compound, and urethane polymer (β that is obtained by further performing a chain extension reaction using a chain extender on the urethane prepolymer (α) Etc.).
Among these, it is preferable that the urethane-based resin used in one aspect of the present invention includes a urethane-based polymer having a polyoxyalkylene skeleton.

  The mass average molecular weight (Mw) of the urethane resin is preferably 10,000 to 200,000, more preferably 12,000 to 150,000, still more preferably 15,000 to 100,000, still more preferably 20,000 to 70,000.

Examples of the polyol to be a raw material of the urethane prepolymer (α) include polyol compounds such as alkylene diol, polyether type polyol, polyester type polyol, polycarbonate type polyol and the like, but there is no particular limitation as long as it is a polyol It may be a difunctional diol or a trifunctional triol.
Among these polyols, diols are preferable from the viewpoint of availability, reactivity and the like.

Examples of the diol include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol and 1,7-heptanediol, 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. These diols may be used alone or in combination of two or more.
Among these diols, when the reaction with a chain extender is further performed, a glycol having a weight average molecular weight of 1000 to 3000 is preferable from the viewpoint of suppressing gelation in the reaction.

As a polyvalent isocyanate compound used as a raw material of urethane type prepolymer ((alpha)), aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate etc. are mentioned.
Examples of aromatic polyisocyanates 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- tetramethyl xylylene diisocyanate, 1, 3- tetramethyl xylylene diisocyanate etc. are mentioned.
As aliphatic polyisocyanate, for example, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HMDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodeca Methylene diisocyanate, 2,4,4- trimethylhexamethylene diisocyanate etc. are mentioned.
As an alicyclic polyisocyanate, for example, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI), 1,3-cyclopentadiisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, Methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, 1,4-bis (isocyanatemethyl) cyclohexane Etc.
The polyvalent isocyanate compound may be a modified product of a compound (polyisocyanate) selected from the above-mentioned aromatic polyisocyanate, aliphatic polyisocyanate, and alicyclic polyisocyanate. Specifically, it may be a trimethylolpropane adduct type modified product of the compound, a burette type modified product obtained by reacting the compound with water, or an isocyanurate modified product obtained by causing the compound to contain an isocyanurate ring.

  Among these polyvalent isocyanate compounds, from the viewpoint of obtaining a urethane-based polymer excellent in adhesiveness, 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2, One or more selected from 6-tolylene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI) and their modified products are preferable From the viewpoint of weather resistance, one or more selected from HMDI, IPDI and their modified products are more preferable.

  The isocyanate group content (NCO%) in the urethane prepolymer (α) is preferably 0.5 to 12% by mass, more preferably 1 to 4% by mass at a value measured according to JIS K 1603. is there.

  The chain extender is preferably a compound having at least one of a hydroxyl group and an amino group, or a compound having at least one of a hydroxyl group and an amino group.

The compound having at least one of hydroxyl group and 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 aliphatic diols 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 aliphatic diamines include ethylene diamine, 1,3-propane diamine, 1,4-butane diamine, 1,5-pentane diamine, 1,6-hexane diamine and the like.
Examples of alkanolamines include monoethanolamine, monopropanolamine, isopropanolamine and the like.
Examples of the bisphenol include bisphenol A and the like.
Examples of the aromatic diamine include diphenylmethane diamine, tolylene diamine and xylylene diamine.

  Examples of the compound having at least one of a hydroxyl group and an amino group include polyols such as trimethylolpropane, ditrimethylolpropane, pentaerythritol and dipentaerythritol, 1-amino-2,3-propanediol, 1-methyl Examples thereof include amino alcohols such as amino-2,3-propanediol and N- (2-hydroxypropylethanolamine), ethylene oxide or propylene oxide adducts of tetramethyl xylylene diamine, and the like.

(Polyisobutylene resin)
The polyisobutylene-based resin (hereinafter, also referred to as “PIB-based resin”) that can be used as the adhesive resin (x1) is a resin having a polyisobutylene skeleton in its main chain or side chain.

  As the mass average molecular weight (Mw) of the PIB resin, the cohesion of the resulting adhesive composition is sufficiently obtained to improve the adhesion of the conductive adhesive sheet, and to prevent the contamination of the adherend. From the viewpoint of wettability to the adherend and solubility in a solvent, it is preferably 30,000 to 1,000,000, more preferably 50,000 to 800,000, and still more preferably 70,000 to 60,000. It is ten thousand.

  Examples of PIB resins include polyisobutylene which is a homopolymer of isobutylene, copolymer of isobutylene and isoprene, copolymer of isobutylene and n-butene, copolymer of isobutylene and butadiene, and these copolymers. Brominated or chlorinated halogenated butyl rubber and the like can be mentioned.

In addition, when PIB type resin is a copolymer, the structural unit derived from isobutylene is contained most among all the structural units.
In the PIB resin used in one aspect of the present invention, the content of the structural unit derived from isobutylene is preferably 80 to 100% by mass, more preferably 100% by mass with respect to all the structural units (100% by mass) of the PIB resin. Is 90 to 100% by mass, more preferably 95 to 100% by mass, and still more preferably 98 to 100% by mass.
These PIB resins may be used alone or in combination of two or more.

Among these, from the viewpoint of improving the durability and weatherability of the adhesive conductive layer (X) to be formed, it has a dense molecular structure when polymerized, and a polymerizable double bond is present on the main chain and side chain. It is preferable that there is a large amount of structural units derived from isobutylene which are not present.
In the PIB-based resin used in one embodiment of the present invention, the content of the structural unit derived from isobutylene having no polymerizable double bond in such a main chain and side chain is the total structural unit of the PIB-based resin Preferably it is 80-100 mass% with respect to 100 mass%, More preferably, it is 90-100 mass%, More preferably, it is 95-100 mass%, More preferably, it is 98-100 mass%.

Moreover, when using PIB type resin, it is preferable to use together PIB type resin with high mass mean molecular weight, and PIB type resin with low mass mean molecular weight.
More specifically, as a PIB-based resin used in one aspect of the present invention, a PIB-based resin (p1) having a mass average molecular weight of 270,000 to 600,000 (hereinafter, also referred to as "PIB-based resin (p1)") It is preferable to use together with a PIB-based resin (p2) (hereinafter, also referred to as “PIB-based resin (p2)”) having a mass average molecular weight of 50,000 to 250,000.
The PIB-based resin (p1) having a high mass average molecular weight contributes to the improvement of the adhesive strength as well as the improvement of the durability and the weather resistance of the adhesive conductive layer (X) formed from the adhesive composition obtained. .
In addition, a PIB resin (p2) having a low mass average molecular weight can be well compatible with the PIB resin (p1) to appropriately plasticize the PIB resin (p1). It contributes to enhancing the wettability to the adherend of X), and improving the adhesive physical properties, flexibility and the like.

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, further preferably 310,000 to 450,000, still more preferably 32 from the above viewpoint. 10,000 to 400,000.
From the above viewpoint, 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, further preferably 140,000 to 220,000, and still more preferably 18 It is ten thousand to two hundred thousand.

The content of PIB resin (p2) 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, per 100 parts by mass of PIB resin (p1). Preferably it is 8-20 mass parts.
If the content ratio of PIB resin (p2) is 5 parts by mass or more, PIB resin (p1) can be sufficiently plasticized, and the adhesive conductive layer (X) formed is wetted to the adherend The adhesion can be improved as well as the properties are improved.
On the other hand, if the content rate of PIB type-resin (p2) is 55 mass parts or less, the adhesive force of the adhesive conductive layer (X) formed, holding power, and durability can be improved.

(Styrenic resin)
The styrenic resin that can be used as the adhesive resin (x1) is a polymer having a structural unit derived from styrene.
In the styrenic resin used in one aspect of the present invention, the content of the structural unit derived from styrene is preferably 5 to 50% by mass, and more preferably, relative to the total structural units (100% by mass) of the styrenic resin. Is 10 to 40% by mass, more preferably 15 to 35% by mass.

  The mass average molecular weight (Mw) of the styrene-based resin is preferably 10,000 to 400,000, more preferably 20,000 to 30,000, and still more preferably 25,000 from the viewpoint of improving the adhesive strength of the conductive pressure-sensitive adhesive sheet. It is 200,000.

The softening point of the styrene-based resin is preferably 80 to 200 ° C., more preferably 90 to 160 ° C., still more preferably 100 to 140 ° C., still more preferably 105, from the viewpoint of improving the adhesive strength of the conductive pressure-sensitive adhesive sheet. It is ~ 135 ° C.
In the present invention, the softening point of the styrene resin means a value measured in accordance with JIS K 2531.

As a styrene resin, for example, styrene-butadiene-styrene triblock copolymer (hereinafter also referred to as "SBS"), styrene-block- (ethylene-co-butylene) -block-styrene triblock copolymer (hereinafter Styrene-block- (ethylene-co-butylene) -block diblock copolymer (hereinafter also referred to as "SEB"), styrene-butadiene diblock copolymer, styrene-isoprene diblock Copolymer, styrene-isoprene-styrene triblock copolymer, styrene-block- (butadiene-co-isoprene) -block diblock copolymer, styrene-block- (butadiene-co-isoprene) -block-styrene tri Block copolymer etc., These in or carboxyl modified product of the copolymer, a copolymer of aromatic vinyl compounds such as styrene and α- methyl styrene.
The above-mentioned styrenic resins may be used alone or in combination of two or more.
Among these styrenic resins, SBS, SEBS and SEB are preferred, and SBS and SEBS are more preferred.
When the styrenic resin is a copolymer, the form of copolymerization is not particularly limited. That is, as the said styrene resin, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient.

(Polyester resin)
The polyester-based resin that can be used as the adhesive resin (x1) is a copolymer obtained by a polycondensation reaction of an acid component and a diol component or a polyol component, and a modified product of the copolymer is also included.
The polycondensation reaction is carried out by a general polyesterification reaction such as direct esterification method or transesterification method.
In addition, the form of the copolymerization of the said polyester-type resin is not specifically limited. That is, as the said polyester-based resin, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient.

  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, azeline 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.

  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, and the like. , 6-hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, etc. Aliphatic glycols, cycloaliphatic glycols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic glycols such as bisphenol A.

  The above-mentioned polyester resins may be used alone or in combination of two or more.

(Polyolefin resin)
The polyolefin resin that can be used as the adhesive resin (x1) is a polymer having a structural unit derived from an olefin compound such as ethylene or propylene.
Examples of polyolefin resins include polyethylenes such as low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, copolymers of ethylene and propylene, ethylene and other α-olefins. Copolymer, copolymer of propylene and other α-olefin, copolymer of ethylene and propylene and other α-olefin, copolymer of ethylene and other ethylenically unsaturated monomer (ethylene -Vinyl acetate copolymer, ethylene-alkyl (meth) acrylate copolymer etc. etc. are mentioned.
In addition, when the said polyolefin resin is a copolymer, the form of a copolymerization is not specifically limited. That is, as said polyolefin resin, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient.

Examples of the above α-olefins include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 4-methyl-1-hexene and the like.
As said ethylenically unsaturated monomer, vinyl acetate, (meth) acrylic acid, alkyl (meth) acrylate, vinyl alcohol etc. are mentioned, for example.

Among these polyolefin resins, polypropylene resins containing structural units derived from propylene such as polypropylene, copolymers of ethylene and propylene, and copolymers of propylene and other α-olefins are preferable.
In addition, said polyolefin resin may be used independently and may be used in combination of 2 or more type.

<Carbon-based filler (x2)>
As a carbon-type filler (x2) contained with the adhesive resin (x1) in the adhesive composition which is a formation material of the adhesive conductive layer (X), the carbon-type filler whose average aspect-ratio is 1.5 or more is preferable.
By containing a carbon-based filler having an average aspect ratio of 1.5 or more, the surface resistivity of the adhesive conductive layer (X) to be formed is lowered, and further, the conductivity by providing the non-adhesive conductive layer (Y) The effect of reducing the surface resistivity of the pressure-sensitive adhesive sheet can be sufficiently exhibited. Moreover, the adhesive force of the adhesive conductive layer (X) can also be made favorable.
The average aspect ratio of the carbon-based filler (x2) is preferably 1.5 or more, more preferably 2 to 10000, more preferably 3 to 5000, more preferably 4 to 1000, further preferably 5 to 5 from the above viewpoint. It is preferably 500, more preferably 6 to 400, still more preferably 10 to 300.

In the present invention, the “aspect ratio” is the ratio of the long side length (H) to the short side length (L) of the target carbon-based filler, that is, “long side length (H) / short It is a value calculated from the side length (L). Further, the “average aspect ratio” is an average value of the calculated “aspect ratios” of ten target carbon-based fillers.
Moreover, length (H) of the long side of a carbon-type filler (x2) means the length of the height direction (longitudinal direction) of the carbon-type filler used as object.
On the other hand, if the short side length (L) of the carbon-based filler (x2) is a cross section perpendicular to the height direction (longitudinal direction) of the target carbon-based filler, the cross section is circular or elliptical. , Diameter or major axis, if the cross section is a polygon, refers to the diameter of the circumscribed circle of the polygon.

The long side length (H) of the carbon-based filler (x2) is preferably 0.01 to 2000 μm, more preferably 0.05 to 1000 μm, still more preferably 0.07 to 500 μm, still more preferably 0. 10 to 100 μm.
In the present invention, the average value of the lengths of the long sides of ten carbon-based fillers arbitrarily selected is regarded as the value of the “length (H) of long sides of carbon-based filler (x2)” described above. You can also.

The length (L) of the short side of the carbon-based filler (x2) 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, still more preferably 7 50 nm.
In the present invention, the average value of the lengths of the short sides of ten carbon-based fillers selected arbitrarily is regarded as the value of the “length (L) of short sides of carbon-based filler (x2)” described above. You can also.

Examples of the shape of the carbon-based filler (x2) include columnar, cylindrical, pyramidal, fibrous, oblate spherical (the sphericity is usually 0.7 or less), and a combination of these.
Among these shapes, from the viewpoint of forming a tacky conductive layer (X) having good conductivity, one type selected from a columnar carbon-based filler, a cylindrical carbon-based filler, and a fibrous carbon-based filler The above is preferable.

The content of the carbon-based filler (x2) in the adhesive composition is preferably 0.01 to 15 parts by mass, more preferably 0.02 to 10 based on 100 parts by mass of the adhesive resin (x1). Parts by mass, more preferably 0.30 to 7.0 parts by mass, further preferably 0.40 to 5.0 parts by mass, still more preferably 0.50 to 4.5 parts by mass, still more preferably 0.70 to It is 3.8 parts by mass.
When the content of the carbon-based filler (x2) is 0.01 parts by mass or more, the surface resistivity of the formed adhesive conductive layer (X) alone is lowered and the non-adhesive conductive layer (Y) is further formed. The effect of lowering the surface resistivity of the conductive pressure-sensitive adhesive sheet can be sufficiently exhibited.
On the other hand, if content of a carbon-type filler (x2) is 15 mass parts or less, the adhesive force of the adhesive conductive layer (X) formed will become favorable.
The conductive pressure-sensitive adhesive sheet of the present invention exhibits excellent antistatic properties and conductivity even when the content of the carbon-based filler (x2) in the adhesive conductive layer (X) is small. It is not necessary to mix many fillers (x2).

  The content of the carbon-based filler (x2) relative to the total amount (100% by mass) of the adhesive composition is usually 0.01 to 10% by mass, preferably 0.30 to 7.0% by mass from the above viewpoint It is more preferably 0.40 to 5.0% by mass, still more preferably 0.50 to 4.5% by mass, and still more preferably 0.70 to 3.8% by mass.

Examples of the carbon-based filler (x2) include carbon nanomaterials, carbon black, milled carbon fibers, graphite and the like, but the surface resistivity of the adhesive conductive layer (X) to be formed is reduced, and the adhesive strength is From the viewpoint of making good, carbon nanomaterials are preferable.
The carbon nanomaterial is made of a substance including a graphite sheet whose main structure is a six-membered ring arrangement structure, but the graphite structure may contain elements other than carbon such as boron and nitrogen, The material may be in the form of containing another substance, and the carbon nanomaterial may be in the form of being modified to another conductive substance.

Examples of carbon nanomaterials include carbon nanotubes (CNTs), carbon nanofibers, carbon nanohorns, carbon nanocones, fullerenes and the like, with carbon nanotubes being preferred.
A carbon nanotube is a cylindrical carbon polyhedron having a cylindrically closed graphite (graphite) sheet having a carbon six-membered ring structure as a main structure.
Carbon nanotubes include single-walled carbon nanotubes having a structure in which a single-layer graphite sheet is closed in a cylindrical shape, double-walled carbon nanotubes having a structure in which a two-layer graphite sheet is closed in a cylindrical shape, and three-layer graphite sheets. The above-described multi-walled carbon nanotubes have a multi-layered structure closed in a concentric cylindrical shape, and any two or more of them can be used in combination.

<Crosslinking agent>
The adhesive composition which is a forming material of the adhesive conductive layer (X) may further contain a crosslinking agent.
In particular, when the above-mentioned acrylic resin (in particular, an acrylic copolymer having the above-mentioned structural unit (a2)) is used as the adhesive resin (x1), the adhesive conductive layer (X) to be formed From the viewpoint of improving the adhesion, it is preferable to contain a crosslinking agent.
As a crosslinking agent, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an aziridine type crosslinking agent, a metal chelate type crosslinking agent, an amine type crosslinking agent, an amino resin type crosslinking agent etc. are mentioned, for example. These crosslinking agents may be used alone or in combination of two or more.
Among these, from the viewpoint of improving the adhesion of the conductive pressure-sensitive adhesive sheet, an isocyanate-based crosslinking agent is preferable.

As an isocyanate type crosslinking agent, for example, 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 and the like Can be mentioned.
The polyvalent isocyanate compound may be a trimethylolpropane adduct type modified product of the above compound, a Burrette type modified product reacted with water, or an isocyanurate type modified product containing an isocyanurate ring.

  The content of the crosslinking agent is preferably 0.01 to 15 parts by mass, more preferably 0.05 to 10 parts by mass, still more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the adhesive resin (x1) It is a department.

<Tackifier>
The adhesive composition which is a forming material of the adhesive conductive layer (X) may further contain a tackifier.
In particular, in the case of using the above-mentioned urethane resin, PIB resin, and styrene resin as the adhesive resin (x1), from the viewpoint of improving the adhesion of the adhesive conductive layer (X) to be formed, adhesion It is preferable to contain a imparting agent.
In addition, the mass mean molecular weight (Mw) of this tackifier is usually less than 10,000, and it distinguishes with the above-mentioned adhesive resin (x1).
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 adhesive conductive layer (X).

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 in accordance with JIS K 2531.

Examples of tackifiers 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-based resins such as epoxy-based resins; Hydrogenated terpene resins obtained by hydrogenating these terpene-based resins; Copolymerization of C5 fractions such as pentene, isoprene, piperine, 1.3-pentadiene, etc. generated by thermal decomposition of petroleum naphtha Obtained C5 petroleum resin and hydrogenated petroleum resin of the C5 petroleum resin; obtainable by copolymerizing a C9 fraction such as indene, vinyl toluene, α- or β-methylstyrene, etc. generated by pyrolysis of petroleum naphtha Examples thereof include C9 petroleum resins and hydrogenated petroleum resins of the C9 petroleum resins.
In the present invention, the tackifier may be used alone or in combination of two or more having different softening points or structures.

The content of the tackifier is preferably 1 to 200 parts by mass, more preferably 5 to 160 parts by mass, and still more preferably 10 to 120 parts by mass with respect to 100 parts by mass of the adhesive resin (x1).
In addition, when adhesive resin (x1) contains acrylic resin, content of the said tackifier is preferably 1-100 mass parts with respect to 100 mass parts of acrylic resins, More preferably, 5-50 mass Part, more preferably 10 to 40 parts by mass.
When the adhesive resin (x1) 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 80-120 mass parts.
When the adhesive resin (x1) 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 (x1) contains a styrene 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 styrene resin. More preferably, it is 25-60 mass parts.
When the adhesive resin (x1) 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 25-60 mass parts.
When the adhesive resin (x1) 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 25-60 mass parts.

<Other additives>
The adhesive composition which is a forming material of the adhesive conductive layer (X) may contain a general-purpose additive generally used together with the adhesive resin as long as the effects of the present invention are not impaired.
Examples of such general-purpose additives include ultraviolet light absorbers, antioxidants, softeners (plasticizers), fillers, rust inhibitors, pigments, dyes, curing agents, curing aids, catalysts, and the like.
When mix | blending these general purpose additives, each compounding quantity of a general purpose additive is preferably 0.01-6 mass parts with respect to 100 mass parts of adhesive resin (x1), More preferably 0.01 2 parts by mass.

  The total content of the adhesive resin (x1) and the carbon-based filler (x2) in the total amount (100% by mass) of the adhesive composition which is a forming material of the adhesive conductive layer (X) is preferably 20% by mass The content is more preferably 30% by mass or more.

  Moreover, when using adhesive resin (x1) which has acrylic resin as a main component, sum total content of adhesive resin (x1) and carbon-type filler (x2) in whole quantity (100 mass%) of adhesive composition The amount is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more.

  When using an adhesive resin (x1) containing a urethane resin as a main component, the total content of the adhesive resin (x1) and the carbon-based filler (x2) in the total amount (100% by mass) of the adhesive composition is Preferably it is 35 mass% or more, More preferably, it is 40 mass% or more, More preferably, it is 45 mass% or more, and the total content of adhesive resin (x1), a carbon-type filler (x2), and a tackifier is Preferably it is 70 mass% or more, More preferably, it is 80 mass% or more, More preferably, it is 90 mass% or more.

  When using an adhesive resin (x1) containing PIB resin as a main component, the total content of the adhesive resin (x1) and the carbon-based filler (x2) in the total amount (100% by mass) of the adhesive composition is Preferably it is 50 mass% or more, More preferably, it is 60 mass% or more, More preferably, it is 70 mass% or more, and the total content of the adhesive resin (x1), the carbon-based filler (x2) and the tackifier is Preferably it is 70 mass% or more, More preferably, it is 80 mass% or more, More preferably, it is 90 mass% or more.

  When using an adhesive resin (x1) containing a styrenic resin as a main component, the total content of the adhesive resin (x1) and the carbon-based filler (x2) in the total amount (100% by mass) of the adhesive composition is Preferably it is 20 mass% or more, More preferably, it is 25 mass% or more, More preferably, it is 30 mass% or more.

In addition, the label with "adhesive resin (x1) which has ZZ-based resin as a main component" means that "the content of ZZ-based resin is the largest among the resins contained in the adhesive resin (x1)" I mean.
The specific content of the ZZ-based resin in the description is usually 50% by mass or more, preferably 65 to 100% by mass, more preferably 75% by mass with respect to the total amount (100% by mass) of the adhesive resin (x1). The amount is preferably 100 to 100% by mass, and more preferably 85 to 100% by mass.

<Method of forming adhesive conductive layer (X)>
There is no restriction | limiting in particular as a formation method of an adhesive conductive layer (X), It can manufacture by a well-known method, For example, the following method (X-1) and (X-2) are mentioned.
Method (X-1): A solution of an organic solvent of an adhesive composition is prepared, the solution is applied on a release sheet described later by a known application method to form a coating film, and the coating film is dried. Method of forming adhesive conductive layer (X).
Method (X-2): The adhesive resin (x1) and the carbon-based filler (x2) are heat-kneaded to prepare a composite, and then the composite is formed into a sheet by a known molding method, Method of forming a conductive layer (X).

(Method (X-1))
Method (X-1) is a preferable formation method when using acrylic resin, urethane resin, PIB resin, etc. as adhesive resin (x1).
Examples of the organic solvent used in method (X-1) include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, isopropanol, dimethylformamide, N-methyl Pyrrolidone, dimethyl sulfoxide and the like can be mentioned.
In addition, you may use the organic solvent used at the time of the synthesis | combination of adhesive resin (x1) as these organic solvents as it is.

In the method (X-1), the carbon-based filler (x2) is preferably blended with the adhesive resin (x1) in the form of a dispersion dispersed in a solvent.
By blending the carbon-based filler (x2) in the form of a dispersion, it can be mixed with the tacky resin (x1) in a low viscosity state, so the carbon-based fillers (x2) easily come close to each other, and the filler The formation of the network of (2) makes it easy to lower the surface resistivity and volume resistivity of the adhesive conductive layer (X) to be formed.
As a solvent used for preparation of the dispersion liquid of a carbon-type filler (x2), water or the above-mentioned organic solvent is mentioned, An organic solvent is preferable.
As a preparation method of the dispersion liquid of a carbon-type filler (x2), a carbon-type filler (x2) is added in a solvent, for example, The method of giving vibration by ultrasonic waves etc. for a fixed time, etc. are mentioned.
The solid concentration of the dispersion of the carbon-based filler (x2) 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.

  In the method (X-1), as a method for applying the solution of the adhesive composition onto the release sheet, for example, spin coating method, spray coating method, bar coating method, knife coating method, roll knife coating method, roll coating Methods, blade coating methods, die coating methods, gravure coating methods and the like.

In addition, after apply | coating the solution of an adhesive composition on a peeling sheet and forming a coating film, it is preferable to dry-process and to remove the solvent contained in a coating film.
Furthermore, in the method (X-1), the coated layer after the drying treatment is subjected to, for example, 7 days to 30 days in an environment of 23 ° C. and 50% RH (relative humidity) in order to improve adhesion. It is preferable to allow the inside of the coating layer to be sufficiently crosslinked by leaving it to a certain degree.

(Method (X-2))
The method (X-2) is a formation method suitable when using a resin that can be durable to heat kneading such as a styrene resin as the adhesive resin (x1).
Examples of the heating and kneading apparatus include a single-screw extruder, a twin-screw extruder, a roll mill, a plasto mill, a Banbury mixer, an intermix, a pressure kneader and the like.
Examples of a method of molding the composite obtained by the heating and kneading apparatus include a melt extrusion method, a calendar method, a compression molding method and the like, and a compression molding method is preferable.
As a specific method of the compression molding method, a sheet-like adhesive conductive layer (X) can be formed by sandwiching the prepared composite between two release sheets and heating and compressing it with a hot press machine or the like. . In place of the two release sheets, the composite prepared by the base material and the release sheet may be sandwiched to form a sheet-like adhesive conductive layer (X).

[Formation material of non-adhesive conductive layer (Y)]
The non-adhesive conductive layer (Y) is selected from the group consisting of a conductive polymer, a carbon-based filler, and a metal oxide from the viewpoint of sufficiently exhibiting the effect of reducing the surface resistivity of the conductive pressure-sensitive adhesive sheet 1 It is preferably a layer containing a conductive material of a kind or more, and more preferably one or more conductive materials selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials, and ITO (indium tin oxide), It is further preferable to include one or more conductive materials selected from the group consisting of polythiophene, PEDOT-PSS, and carbon nanomaterials.

The density of the conductive material contained in the non-adhesive conductive layer (Y) is preferably 0.8 to 2.5 g / cm ³ , more preferably 0.8 to 2.5, from the viewpoint of reducing the weight of the conductive adhesive sheet. 2.0 g / cm ^3, more preferably from 0.8~1.7g / cm ^3.
Hereinafter, the electrically-conductive material which comprises a non-adhesive conductive layer (Y) is demonstrated.

<Conductive polymer>
Examples of the conductive polymer include polythiophene, PEDOT-PSS (poly (3,4-ethylenedioxythiophene) -poly (styrenesulfonic acid)), polyaniline, polypyrrole, polyquinoxaline and the like.
Among these, polythiophene and PEDOT-PSS are preferable.

The non-adhesive conductive layer (Y) containing a conductive polymer preferably contains a non-adhesive resin together with the conductive polymer, and as the non-adhesive resin, acrylic resins, urethane resins, PIB resins And one or more non-adhesive resins selected from styrenic resins are preferred.
When using a conductive polymer as the conductive material, the content of the conductive polymer is preferably 4 to 100% by mass, more preferably the total amount (100% by mass) of the non-adhesive conductive layer (Y). 8 to 100% by mass.

There is no restriction | limiting in particular as a formation method of the non-adhesive conductive layer (Y) containing a conductive polymer, For example, the solution of the organic solvent containing a conductive polymer is prepared, The said solution is a base material or a release sheet There is a method of forming a coating film by coating by a known coating method and drying the coating film.
About the kind of organic solvent used for the said method, and the coating method of a solution, it is the same as that of the description regarding "the method (X-1)" which is a formation method of the above-mentioned adhesive conductive layer (X).

<Carbon-based filler>
As a carbon-type filler, the same thing as the above-mentioned carbon-type filler (x2) is mentioned, A carbon nanomaterial is preferable.
The non-adhesive conductive layer (Y) containing a carbon-based filler preferably contains a non-adhesive resin together with the carbon-based filler, and as the non-adhesive resin, acrylic resins, urethane resins, PIB resins, and One or more non-adhesive resins selected from styrenic resins are preferred.
When using a carbon-based filler as the conductive material, the content of the carbon-based filler is preferably 0.1 to 20% by mass, more preferably the total amount (100% by mass) of the non-adhesive conductive layer (Y). Is preferably 0.5 to 15% by mass, more preferably 1.0 to 10% by mass, and still more preferably 2.0 to 7% by mass.

There is no restriction | limiting in particular as a formation method of the non-adhesive conductive layer (Y) containing a carbon-type filler, For example, the dispersion liquid of a carbon-type filler and the solution of the organic solvent of non-adhesive resin are mixed, and resin After preparing a solution of the composition, the solution is applied onto a substrate or a release sheet by a known coating method to form a coated film, and the coated film is dried to form a film.
About the kind of organic solvent used for the said method, the preparation method of the dispersion liquid of a carbon-type filler, and the application method of a solution, it is related with "the method (X-1)" which is the formation methods of the above-mentioned adhesive conductive layer (X). The same as described.

Moreover, as a formation method of the non-adhesive conductive layer (Y) containing a carbon-type filler, after heat-kneading a carbon-type filler and non-adhesive resin and preparing a composite, the said composite is sheeted by the well-known shaping | molding method It may be a method of obtaining it in a form.
About the heating kneader used for the said method, and the formation method of a composite, it is the same as that of the description regarding "the method (X-2)" which is a formation method of the above-mentioned adhesive conductive layer (X).

<Metal oxide>
As metal oxides, ITO (indium tin oxide), ZnO (zinc oxide), IZO (zinc indium oxide), AZO (zinc aluminum oxide), GZO (zinc gallium oxide), IGZO (indium gallium zinc oxide), ATO (aluminium oxide) And tin oxide (antimony oxide).
Among these, ITO (indium tin oxide) is preferable.
When a metal oxide is used as the conductive material, the non-adhesive conductive layer (Y) is preferably a layer formed only of the metal oxide.
In addition, as a formation method of the non-adhesive conductive layer (Y) containing a metal oxide, the method of forming with respect to a base material by vapor deposition is preferable.

〔Base material〕
The substrate used for the conductive adhesive sheet according to one aspect of the present invention is appropriately selected according to the application of the conductive adhesive sheet, but may be an insulating substrate containing an insulating material, such as metal It may be a conductive substrate containing a conductive material.

In the present invention, the 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).
As the insulating substrate, for example, various papers such as high quality paper, art paper, coated paper, glassine paper, etc. and laminated paper obtained by laminating thermoplastic resin such as polyethylene on these paper substrates; porous materials such as non-woven fabric Materials: Plastic films or sheets made of polyolefin resins such as polyethylene resin and polypropylene resin, polyester resins such as polybutylene terephthalate resin, polyethylene terephthalate resin, acetate resin, ABS resin, polystyrene resin, vinyl chloride resin, etc. Mixture of these resins And a plastic film or sheet made of a laminate of these plastic films or sheets.
The base material such as the plastic film or sheet may be unstretched, or may be stretched in a uniaxial or biaxial direction such as longitudinal or transverse.
In addition, these insulating substrates (particularly plastic films or sheets) may further contain UV absorbers, light stabilizers, antioxidants, antistatic agents, slip agents, antiblocking agents, coloring agents, etc. Good.

As the conductive substrate, for example, a metal foil, a film or sheet obtained by laminating a metal foil with the above-described resin or the like forming the insulating substrate, a film obtained by subjecting the surface of the insulating substrate to metal deposition treatment or A sheet, a film or sheet obtained by performing an antistatic treatment on the surface of the above-mentioned insulating substrate, a sheet in which a metal wire is knitted in a mesh shape, and the like can be mentioned.
In addition, as a metal used for a conductive base material, aluminum, copper, silver, gold etc. are mentioned, for example.

  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 easy handling.

When the substrate is a plastic film or sheet, from the viewpoint of improving the adhesion between the substrate and the non-adhesive conductive layer (Y), the surface of the substrate may be oxidized or roughened as needed. It is preferable to apply a surface treatment of
The oxidation method is not particularly limited, and examples thereof include corona discharge treatment method, plasma treatment method, chromic acid oxidation (wet process), flame treatment, hot air treatment, ozone / ultraviolet radiation treatment and the like. Moreover, it does not specifically limit as a roughening method, For example, the sand blasting method, the solvent treatment method, etc. are mentioned. Although these surface treatments are suitably selected according to the kind of base material, a corona discharge treatment method is preferable from a viewpoint of the improvement effect of adhesiveness with a non-adhesive conductive layer (Y), and operativity. Also, primer treatment can be performed.

[Release sheet]
Moreover, as a peeling sheet used for the electroconductive adhesive sheet of 1 aspect of this invention, the peeling sheet in which double-sided peeling processing was carried out, the peeling sheet etc. which were carried out single-sided peeling processing etc. are used, And the like.

Examples of the release sheet substrate include paper substrates such as glassine paper, coated paper and wood free paper, laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper substrates, or polyethylene terephthalate resin, polybutylene terephthalate Examples thereof include resins, polyester resin films such as polyethylene naphthalate resin, and plastic films such as polypropylene resin and polyolefin resin films such as polyethylene resin.
Examples of release agents include silicone resins, olefin resins, isoprene resins, rubber elastomers such as butadiene resins, long chain alkyl resins, alkyd resins, fluorine resins, and the like.

  The thickness of the release sheet is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 150 μm.

[Method of manufacturing conductive pressure-sensitive adhesive sheet, physical properties]
The conductive pressure-sensitive adhesive sheet according to one aspect of the present invention is produced by appropriately bonding the adhesive conductive layer (X) and the non-adhesive conductive layer (Y) formed by the above-mentioned forming method, and the substrate and the release sheet. can do.

The peak top value of the probe tack to the surface of the adhesive conductive layer (X) of the conductive adhesive sheet according to one aspect of the present invention is preferably 0.1 N or more, more preferably 0.1 to 49 N, still more preferably Is 0.5 to 49 N, more preferably 1.0 to 49 N.
In addition, the value of the peak top of the said probe tack means the value measured by the method as described in an Example. Moreover, the value of the peak top of the said probe tack | tuck is a physical-property value used as the parameter | index of the adhesive force of a conductive adhesive sheet, Comprising: It has high adhesive force, so that the said value is large.

The surface resistivity (ρ _S ) measured from the surface side of the adhesive conductive layer (X) of the conductive adhesive sheet according to one embodiment of the present invention is preferably 9.0 × 10 ⁴ Ω / sq or less, more preferably It is 1.0 × 10 ⁴ Ω / □ or less, more preferably 5.0 × 10 ³ Ω / □ or less, still more preferably 2.0 × 10 ³ Ω / □ or less.
In addition, the value of said "surface resistivity measured from the surface side of the adhesive conductive layer (X) which a conductive adhesive sheet has" is at least the adhesive conductive layer (X) and the non-adhesive conductive layer (Y). It is a value of the surface resistivity measured from the surface side of the adhesive conductive layer (X) which exposed the conductive adhesive sheet of the present invention laminated, and the surface resistivity of the above-mentioned "adhesive conductive layer (X) alone ( It differs from the value of ρ _SX ).

  The physical properties of each component used in the following Examples and Comparative Examples, and the physical properties of the conductive pressure-sensitive adhesive sheet, the adhesive conductive layer (X), and the non-adhesive conductive layer were measured by the methods described below.

<Mass average molecular weight (Mw)>
It measured on condition of the following using the gel permeation chromatograph apparatus (Tosoh Corp. make, product name "HLC-8020"), and the value measured by standard polystyrene conversion was used.
(Measurement condition)
Column: “TSK guard column HXL-H”, “TSK gel GMHXL (× 2)”, and “TSK gel G2000 HXL” (all manufactured by Tosoh Corporation) sequentially.
・ Column temperature: 40 ° C
-Developing solvent: tetrahydrofuran-Flow rate: 1.0 mL / min

<Aspect ratio of carbon filler, length of long side and short side>
Using a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation, product name "S-4700"), observe 10 particles of the carbon-based filler randomly extracted, and measure the length and length of each long side. The length of the side was measured, and the average value of 10 particles of the carbon-based filler was taken as the “long side length (H)” and “short side length (L)” of the filler. Further, the aspect ratio (H / L) was calculated from “length of long side (H) / length of short side (L)”.

<Softening point>
It measured based on JIS K 2531.

<Density>
It measured based on JISZ 8807: 2012.

<Probe Tack>
It measured based on JISZ0237 (1991).
Specifically, after leaving a specimen of 10 mm × 10 mm in size for 24 hours under an environment of 23 ° C. and 50% RH (relative humidity), the surface of the layer to be measured of the specimen is exposed. The probe tack value against the surface of the layer was measured using a tacking tester (product name “PROBE TACK TESTER” manufactured by Rigaku Kogyo Co., Ltd.).
The probe tack value is a stainless steel probe with a diameter of 5 mm for 1 second with a contact load of 0.98 N / cm ² , and then the probe is brought into contact with the surface of the layer to be measured at a speed of 600 mm / sec. The force required to move away from the surface was taken as the probe tack value of the surface of the layer.
In addition, for the surface of the non-adhesive conductive layer, the peak top of the probe tack value was measured. Moreover, with respect to the surface of the adhesive conductive layer (X) which a conductive adhesive sheet has, the peak top and integral value of the probe tack value were measured.
Furthermore, when there is no tackiness on the surface of the layer to be measured and the peak top of the probe tack value can not be measured, the value of the peak top is set to "0 (N)".

<Surface resistivity, volume resistivity>
It measured based on JISK7194.
Specifically, after leaving a test piece of 20 mm × 40 mm in size for 24 hours under an environment of 23 ° C. and 50% RH (relative humidity), the surface of the layer to be measured of the test piece is exposed. The surface resistivity and the volume resistivity were measured using a low resistivity meter (product name "Loresta GP MCP-T610" manufactured by Mitsubishi Chemical Analytech Co., Ltd.).
The surface resistivity is measured three times, the volume resistivity is measured five times, and Tables 1 and 2 show average values of measured values obtained in the respective measurements.

In the measurement of the surface resistivity and volume resistivity of the adhesive conductive layer (X) alone, a laminate in which only the adhesive conductive layer (X) is sandwiched between the two release sheets is used as a test piece, The release sheet on one side of the test piece was removed, and these values were measured on the surface of the adhesive conductive layer (X) exposed.
Moreover, in the measurement of the surface resistivity and volume resistivity of the non-adhesive conductive layer alone, the non-adhesive conductive layer-provided substrate is used as a test piece, and the surface of the non-adhesive conductive layer of the test piece is These values were measured.
Furthermore, in the measurement of the surface resistivity of a conductive adhesive sheet, the base material, the non-adhesive conductive layer, the adhesive conductive layer (X) and the peeling sheet which were produced in the example and the comparative example are laminated in this order The pressure-sensitive adhesive sheet was used as a test piece, the release sheet of the test piece was removed, and only the surface resistivity value was measured with respect to the surface of the exposed adhesive conductive layer (X).

Production Example 1
(Preparation of a substrate with a non-adhesive conductive layer (Y-1))
A solution of polythiophene (SOKEN CHEMICAL CO., LTD.) On a 50 μm thick polyethylene terephthalate (PET) film (made by Toray Industries, Inc., trade name “Lumirror”, surface resistivity: 1.18 × 10 ¹⁸ Ω / □) used as a substrate Made by Co., Ltd., trade name "Berasol IW-103") to a dry thickness of 2.4 μm to form a coating film, and the coating film is dried to obtain a non-adhesive conductive layer containing polythiophene A substrate with (Y-1) was obtained.

Production Example 2
(Preparation of a substrate with a non-adhesive conductive layer (Y-2))
Poly (3,4-ethylenedioxythiophene) -poly based on 100 parts by mass (solid content) of an acrylic water-soluble polymer (manufactured by Arakawa Chemical Industries, Ltd., trade name "Tanomori G-37", polyacrylic acid) A solution containing 10 parts by mass (solid content ratio) of (styrene sulfonic acid) (PEDOT-PSS) dispersion liquid (manufactured by Agfa, trade name "Orgacon S305") and 10 parts by mass of ethylene glycol was prepared.
Then, the solution is applied onto the same PET film as used in Production Example 1 so that the thickness after drying becomes 1.0 μm, a coating film is formed, the coating film is dried, and PEDOT-PSS is obtained. The base material with the non-adhesive conductive layer (Y-2) containing was obtained.

Production Example 3
(Preparation of a substrate with a non-adhesive conductive layer (Y-3))
Multi-walled carbon nanotube (CNT) (trade name "NC7000" manufactured by Nanosil, as described later) with respect to 100 parts by mass (solid content) of a styrene resin (trade name "1726M" manufactured by Kraton Co., Ltd., SEBS) 10 parts by mass (solid content ratio) was added, and the mixture was kneaded under the conditions of 100 ° C. and 50 rpm using a heating kneader (product name “30C150” manufactured by Toyo Seiki Seisakusho Co., Ltd.) to obtain a composite.
Then, the above composite is sandwiched between the same PET film as used in Production Example 1 and a 75 μm-thick release sheet (Lintech Co., Ltd., trade name “SP-PET 751031”), and a hot press (tester industry) It heat-pressed for 10 minutes on 130 degreeC and 10 Mpa conditions using the corporation | Co., Ltd. | KK make and product name "SA-302". After hot pressing, the release sheet was removed to obtain a substrate with a non-adhesive conductive layer (Y-3) containing 100.0 μm thick SEBS and CNT (10 parts by mass).

Production Example 4
(Preparation of a substrate with a non-adhesive conductive layer (Y-4))
Non-adhesive conductive layer (Y-4) containing SEBS and CNT (4 parts by mass) having a thickness of 100.0 μm in the same manner as in Production Example 3 except that the compounding amount of multi-walled carbon nanotubes is changed to “4 parts by mass” ) Was obtained.

In the present example and the comparative example, in addition to the non-adhesive conductive layer-attached substrate produced according to the above-mentioned Production Examples 1 to 4, the following non-adhesive conductive layer-attached substrate was also used.
-"Substrate with non-adhesive conductive layer (YA) comprising ITO": trade name "ITO-polyethylene terephthalate" (manufactured by Oike Kogyo Co., Ltd.). An ITO film having a thickness of 1.6 μm is vapor deposited on one side of a 50 μm-thick PET film (surface resistivity: 1.18 × 10 ¹⁸ Ω / □).
-"Substrate with non-adhesive conductive layer (Y-B) made of copper": trade name "Nicaflex" (manufactured by Nikkan Kogyo Co., Ltd.). A 35.0 μm-thick copper film is bonded with an adhesive on one side of a 50 μm-thick PET film (surface resistivity: 1.18 × 10 ¹⁸ Ω / □).
· Base material with non-adhesive conductive layer (Y-C) made of aluminum: trade name “Metal Me # 50” (manufactured by Toray Film Co., Ltd. 50 μm thick PET film (surface resistivity: 1.18 × 10 ¹⁸⁾ An aluminum film having a thickness of 10.0 μm is deposited on one side of Ω / □).

  Table 1 shows various physical properties of the non-adhesive conductive layer of the non-adhesive conductive layer-attached substrate used in the present example and the comparative example.

Examples 1-15, Comparative Examples 1-8
(1) Formation of adhesive conductive layer (X) Carbon-based filler (x2) of the type and blending amount (solid content ratio to 100 parts by mass (solid content) of adhesive resin) shown in Table 2 is added to ethyl acetate Vibration with ultrasonic waves (42 kHz, 125 W) was applied for 1 hour with an ultrasonic cleaner to prepare a dispersion of carbon-based filler (x2) having a solid concentration of 0.5% by mass in advance.
Subsequently, the dispersion liquid of the said carbon-type filler (x2) is added to 100 mass parts (solid content) of adhesive resin (x1) of the kind shown in Table 2, and also the kind and compounding quantity (solid content ratio) shown in Table 2 The cross-linking agent and the tackifier were added as needed. Then, it diluted suitably with ethyl acetate, and stirred until it became uniform, and the solution of the adhesive composition was prepared.
Then, the solution of the adhesive composition prepared as described above is subjected to release treatment of a release sheet (Lintech Co., Ltd., trade name “SP-PET 381031”, thickness: 38 μm, polyethylene terephthalate film whose surface has been subjected to silicone release treatment) It apply | coated on the surface and formed the coating film, and it was made to dry and the application layer was formed.
Next, a release sheet of the same type as described above is separately laminated on the coating layer and allowed to stand in an environment of 23 ° C. and 50% RH (relative humidity) for 14 hours, after which the coating layer is sufficiently crosslinked. A laminate in which only the adhesive conductive layer (X) having the thickness shown in 2 was sandwiched between two release sheets was obtained.
(2) Preparation of Conductive Pressure-Sensitive Adhesive Sheet In Examples 1 to 15 and Comparative Examples 7 to 8, the adhesive conductive layer (X) which is exposed by removing one release sheet of the laminate is shown in Table 2. The non-adhesive conductive layer of the base material with non-adhesive conductive layer of various kinds was bonded together, and the conductive adhesive sheet was produced.
In Comparative Examples 1 to 6, an adhesive conductive layer (X) exposed by removing one release sheet of the laminate and a PET film having a thickness of 50 μm (trade name “Lumirror” manufactured by Toray Industries, Inc.) Were bonded to produce a conductive pressure-sensitive adhesive sheet.

Example 16
(1) Formation of adhesive conductive layer (X) Multi-walled carbon nanotube relative to 100 parts by mass (solid content) of a styrene resin (trade name "P-907Y" manufactured by Toyo Address Co., Ltd., details will be described later) (CNT) (Nanosil Co., Ltd., trade name "NC7000", details will be described later) are added in the compounding amount (solid content ratio) shown in Table 2, and a heating kneader (product made by Toyo Seiki Co., Ltd., product name " The mixture was kneaded under the conditions of 100 ° C. and 50 rpm using 30C150 ′ ′) to obtain a composite.
Then, the above composite is sandwiched between two release sheets (Lintech Co., Ltd., trade name “SP-PET 751031”, thickness: 75 μm), and a hot press (made by Tester Sangyo Co., Ltd., trade name “SA-302”. It heat-pressed for 10 minutes on 130 degreeC and 10 MPa conditions using "), and obtained the laminated body clamped only by the adhesive conductive layer (X) by the peeling sheet of 2 sheets.
(2) Production of Conductive Pressure-Sensitive Adhesive Sheet A pressure-sensitive adhesive conductive layer (X) containing a styrene-based resin, which is exposed by removing one release sheet of the laminate, and a group with a non-adhesive conductive layer (Y-2) The non-adhesive conductive layer of the material was pasted together to produce a conductive pressure-sensitive adhesive sheet.

The detail of each component in the adhesive composition used by the Example and comparative example which were shown by Table 2 is as follows.
(Adhesive resin (x1))
· "Acrylic resin": methyl acetate solution of acrylic polymer consisting of n-butyl acrylate (BA) and acrylic acid (AA), BA / AA = 90.0 / 10.0 (parts by mass), Mw: 700,000 , Solid concentration: 33.6% by mass.
-"Urethane-based resin": manufactured by Lion Specialty Chemicals Inc., trade name "US-902A", urethane-based resin, Mw = 56,000.
-"PIB-based resin": 90.9 parts by mass (solid content ratio) of PIB-based resin with a Mw of 340,000 (manufactured by BASF, trade name "Opanol B50"), and PIB-based resin with a Mw of 200,000 (manufactured by BASF, a product) Resin mixed with 9.1 parts by mass (solids ratio) with the name "Opanol B30".
-"Styrene-based resin": Toyo Address Co., Ltd., trade name "P-907Y", mixed resin containing SEBS and SEB, total content of SEBS and SEB = 30% by mass, softening point = 112 ° C.

(Carbon based filler (x 2))
-"NC 7000": trade name, manufactured by Nanosil, cylindrical multi-walled carbon nanotubes, average aspect ratio (H / L): 150, long side length (H): 1.5 μm, short side length (L ): 10 nm.
・ "AMC": trade name, manufactured by Ube Industries, Ltd., cylindrical multi-walled carbon nanotube, average aspect ratio (H / L): 100, long side length (H): 1.1 μm, short side length (L): 11 nm.

(Crosslinking agent)
"Corronate L": trade name, manufactured by Tosoh Corporation, an isocyanate crosslinking agent, solid content concentration: 75% by mass.
(Tackifier)
-"Alcon P-125": trade name, manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point: 125 ° C.
"YS Polystar K 125": trade name, manufactured by Yasuhara Chemical Co., Ltd., terpene phenolic resin, softening point: 125 ° C.
(Other ingredients)
-A mixture of components (tackifier, plasticizer, etc.) other than the component (x1) contained in "P-907Y" used as a styrene resin.

Examples 17 to 23
A commercially available conductive double-sided tape (manufactured by Nisshin EM Co., Ltd., trade name "conductive carbon double-sided tape 7311", an adhesive layer containing an acrylic resin and a carbon powder is sandwiched by two release sheets The pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet) was used as a pressure-sensitive conductive layer (X).
A pressure-sensitive adhesive layer (adhesive conductive layer (X)) exposed by removing one release sheet of the above-mentioned commercially available conductive double-sided tape and a non-adhesive conductive layer (Y-1) of the type shown in Table 3 ) And a non-adhesive conductive layer of a substrate with a non-adhesive conductive layer (Y-4) were laminated to prepare a conductive pressure-sensitive adhesive sheet.

Comparative Example 9
Pressure-sensitive adhesive layer (adhesive conductive layer (X)) showing one release sheet of the above-mentioned commercially available conductive double-sided tape and PET film of 50 μm thickness (trade name “Lumirror” manufactured by Toray Industries, Inc.) And were bonded together to prepare a conductive pressure-sensitive adhesive sheet.

  The various physical-property values measured based on the said method are shown in Table 2 and Table 3 about the electroconductive adhesive sheet produced as mentioned above.

  According to Tables 2 and 3, the conductive pressure-sensitive adhesive sheets of Examples 1 to 23 have good adhesive force and lower surface resistivity than the conductive pressure-sensitive adhesive sheets of Comparative Examples 1 to 9, and have antistatic properties. And it turns out that it is excellent in conductivity.

The conductive pressure-sensitive adhesive sheet of the present invention has excellent adhesive strength and low surface resistivity, and thus is excellent in antistatic properties and conductivity.
Therefore, the conductive adhesive sheet of the present invention is, for example, an electromagnetic shielding material of a container for housing an electronic device such as a computer or communication device, a ground line of an electric component or the like, and further fire prevention by sparks generated from static electricity such as triboelectric It is suitable as a joining member used for members, such as materials.

1A, 1B, 2A, 2B, 3, 4 conductive adhesive sheet 11 adhesive conductive layer (X)
11a first adhesive conductive layer (X-I)
11b Second adhesive conductive layer (X-II)
12 Non-adhesive conductive layer (Y)
12a first non-adhesive conductive layer (Y-I)
12b Second non-adhesive conductive layer (Y-II)
13 Base material 14 Peeling sheet 21 Bilayer 21a 1st Bilayer 21b 2nd Bilayer 22 Trilayer

Claims (16)

A conductive pressure-sensitive adhesive sheet comprising at least a tacky conductive layer (X) and a non-tacky conductive layer (Y),
The surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is 1.0 × 10 ^{2 to} 1.0 × 10 ¹⁰ Ω / □,
The surface resistivity (ρ _SY ) of the non-adhesive conductive layer (Y) alone is 1.0 × 10 ^{−2 to} 1.0 × 10 ⁸ Ω / □, and
Equation (1): 0 <satisfies the _{log 10 (ρ SX / ρ SY} ) ≦ 6.0, the conductive adhesive sheet. The thickness of the adhesive conductive layer _{(X) (t} X) is 1～1200Myuemu, conductive adhesive sheet according to claim 1. The thickness of the non-adhesive electrically conductive layer _{(Y) (t} Y) is 0.01～200Myuemu, conductive adhesive sheet according to claim 1 or 2.   The electroconductive according to any one of claims 1 to 3, wherein the adhesive conductive layer (X) is a layer formed from an adhesive composition containing an adhesive resin (x1) and a carbon-based filler (x2). Adhesive sheet.   The adhesive resin (x1) contained in the adhesive composition is at least one selected from the group consisting of acrylic resins, urethane resins, rubber resins, styrene resins, polyester resins, and polyolefin resins. The electroconductive adhesive sheet of Claim 4 containing the adhesive resin of 5.   The electroconductive adhesive sheet of Claim 4 or 5 whose average aspect-ratio of the carbon-type filler (x2) contained in the said adhesive composition is 1.5 or more.   The content of the carbonaceous filler (x2) contained in the adhesive composition is 0.01 to 15 parts by mass with respect to 100 parts by mass of the adhesive resin (x1). The electroconductive adhesive sheet as described in 1 or 2.   The conductive adhesive sheet according to any one of claims 4 to 7, wherein the carbon-based filler (x2) contained in the adhesive composition is a carbon nanomaterial.   The non-adhesive conductive layer (Y) is a layer containing one or more conductive materials selected from the group consisting of a conductive polymer, a carbon-based filler, and a metal oxide. The electroconductive adhesive sheet as described in a term.   The non-adhesive conductive layer (Y) is a layer comprising one or more conductive materials selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials, and ITO (indium tin oxide). The electroconductive adhesive sheet of any one of the above. The electroconductive adhesive sheet of Claim 9 or 10 whose density of the electrically-conductive material contained in a non-adhesive conductive layer (Y) is 0.8-2.5 g / cm < ³ >.   The electroconductive adhesive sheet of any one of Claims 1-11 which has the structure which laminated | stacked the base material, the non-adhesive conductive layer (Y), and the adhesive conductive layer (X) in this order.   The electroconductive adhesive sheet of Claim 12 which has a two-layer body comprised from a non-adhesive conductive layer (Y) and an adhesive conductive layer (X) on both surfaces of a base material, respectively. The conductive adhesive sheet according to claim 12, wherein the substrate is an insulating substrate having a surface resistivity of 1.0 × 10 ¹⁴ Ω / □ or more.   The electroconductive according to any one of claims 1 to 11, having a configuration in which a two-layered body composed of an adhesive conductive layer (X) and a non-adhesive conductive layer (Y) is sandwiched by two release sheets. Adhesive sheet. Two release sheets of a three-layered body in which the first adhesive conductive layer (X-I), the non-adhesive conductive layer (Y), and the second adhesive conductive layer (X-II) are laminated in this order The electroconductive adhesive sheet of any one of Claims 1-11 which has the structure clamped by this.

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