KR102388869B1 - Conductive adhesive sheet - Google Patents

Abstract

A conductive pressure-sensitive adhesive sheet having at least an adhesive conductive layer (X) and a non-stick conductive layer (Y), wherein the adhesive conductive layer (X) includes an adhesive resin (x1) and a carbon-based filler (x2) having an average aspect ratio of 1.5 or more It is a layer formed of an adhesive composition, and 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 non-stick conductive layer (Y), Provided is a conductive adhesive sheet, which is a layer comprising at least one conductive material selected from the group consisting of conductive polymers, carbon-based fillers, and metal oxides. The said electroconductive adhesive sheet has the outstanding antistatic property and electroconductivity while having favorable adhesive force.

Description

Conductive adhesive sheet {CONDUCTIVE ADHESIVE SHEET}

The present invention relates to an electrically conductive adhesive sheet.

Conventionally, for various bonding of electronic shielding materials for containers housing electronic devices such as computers and communication devices, grounding wires for electrical parts, etc., and further, ignition prevention materials caused by sparks generated from static electricity such as triboelectricity, simple adhesive properties A conductive adhesive sheet having a

In order to impart antistatic properties and conductivity to the pressure-sensitive adhesive composition used in the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet, a conductive substance such as a metal powder such as copper powder, silver powder, nickel powder, or aluminum powder is dispersed in an adhesive resin. things are being used

For example, Patent Document 1 discloses a conductive adhesive in which at least one of carbon nanotubes and carbon microcoils is dispersed in an adhesive as a conductive substance, and a conductive adhesive sheet using the conductive adhesive.

Japanese Patent Laid-Open No. 2001-172582

However, in order to improve the conductivity of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet, it is necessary to mix a large amount of a conductive material in the pressure-sensitive adhesive composition, which is a material for forming the pressure-sensitive adhesive layer, so that the conductive material particles are in close contact with each other. there is.

However, when a large amount of an electrically conductive substance is mix|blended in an adhesive composition, there exists a tendency for the adhesive force of the adhesive layer formed from the said adhesive composition to fall. On the other hand, if the content of the conductive substance in the pressure-sensitive adhesive layer is reduced in order to increase the adhesive strength, there is a problem of a contradiction in the conductivity of the pressure-sensitive adhesive layer.

The electroconductive adhesive sheet disclosed by patent document 1 is still inadequate in the point of improving both adhesive force and electroconductivity.

An object of this invention is to provide the electroconductive adhesive sheet excellent in antistatic property and electroconductivity while having favorable adhesive force.

The present inventors have found that a conductive adhesive sheet having a pressure-sensitive adhesive conductive layer formed of a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive resin and a carbon-based filler of a specific shape in a specific ratio and a non-adhesive conductive layer containing a specific conductive material can solve the above problems found, and completed the present invention.

That is, the present invention provides the following [1] to [14].

[1] A conductive adhesive sheet having at least an adhesive conductive layer (X) and a non-stick conductive layer (Y),

The adhesive conductive layer (X) is a layer formed of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin (x1) and a carbon-based filler (x2) having an average aspect ratio of 1.5 or more,

Content of the carbon-based filler (x2) contained in the said adhesive composition is 0.01-15 mass parts with respect to 100 mass parts of adhesive resin (x1),

The conductive adhesive sheet in which the non-stick conductive layer (Y) is a layer containing at least one conductive material selected from the group consisting of conductive polymers, carbon-based fillers, and metal oxides.

[2] The conductive adhesive sheet according to the above [1], wherein the surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is 1.0×10 ² to 1.0×10 ¹⁰ Ω/□.

[3] The conductive adhesive sheet according to the above [1] or [2], wherein the surface resistivity (ρ _SY ) of the non-stick conductive layer (Y) alone is 1.0×10 ⁻² to 1.0×10 ⁸ Ω/□.

[4] The conductive adhesive sheet according to any one of [1] to [3], wherein the carbon-based filler (x2) contained in the pressure-sensitive adhesive composition is a carbon nanomaterial.

[5] The above [1] wherein the non-stick conductive layer (Y) is a layer containing at least one conductive material selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials, and ITO (indium tin oxide). The conductive adhesive sheet according to any one of [4] to [4].

[6] The conductive adhesive sheet according to any one of [1] to [5], wherein the density of the conductive material contained in the non-stick conductive layer (Y) is 0.8 to 2.5 g/cm 3 .

[7] At least one adhesive resin selected from the group consisting of an acrylic resin, a urethane-based resin, a polyisobutylene-based resin, a styrene-based resin, a polyester-based resin, and a polyolefin-based resin, the adhesive resin (x1) contained in the adhesive composition The conductive adhesive sheet according to any one of [1] to [6], comprising:

[8] The conductive adhesive sheet according to any one of [1] to [7], wherein the thickness (t _X ) of the adhesive conductive layer (X) is 1 to 1200 µm.

[9] The conductive adhesive sheet according to any one of [1] to [8], wherein the thickness (t _Y ) of the non-stick conductive layer (Y) is 0.01 to 200 µm.

[10] The conductive adhesive sheet according to any one of [1] to [9], having a structure in which a base material, a non-stick conductive layer (Y), and an adhesive conductive layer (X) are laminated in this order.

[11] The conductive adhesive sheet according to the above [10], each having a two-layer body composed of a non-adhesive conductive layer (Y) and an adhesive conductive layer (X) on both surfaces of the substrate.

[12] The conductive adhesive sheet according to [10] or [11], wherein the substrate is an insulating substrate having a surface resistivity of 1.0×10 ¹⁴ Ω/□ or more.

[13] The conductivity according to any one of [1] to [9], wherein the two-layer body composed of the adhesive conductive layer (X) and the non-stick conductive layer (Y) is sandwiched by two release sheets. adhesive sheet.

[14] A configuration in which a three-layer body in which the first adhesive conductive layer (X-I), the non-stick conductive layer (Y) and the second adhesive conductive layer (X-II) are laminated in this order is sandwiched by two release sheets The conductive pressure-sensitive adhesive sheet according to any one of [1] to [9].

The electroconductive adhesive sheet of this invention is excellent in antistatic property and electroconductivity while having favorable adhesive force.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the electroconductive adhesive sheet which has a base material which is a structure of one suitable embodiment of the electroconductive adhesive sheet of this invention.
It is sectional drawing of the electroconductive adhesive sheet without a base material which is a structure of one suitable embodiment of the electroconductive adhesive sheet of this invention.

In this specification, "mass average molecular weight (Mw)" is a standard polystyrene conversion value measured by the gel permeation chromatography (GPC) method, It is a value specifically measured based on the method described in the Example.

In addition, for example, "(meth)acrylate" is used as a word which shows both "acrylate" and "methacrylate", and the same applies to other similar terms.

In addition, unless otherwise indicated, "the surface resistivity of an electroconductive adhesive sheet" means the surface resistivity measured from the surface side of the adhesive conductive layer (X) which an electroconductive adhesive sheet has.

In addition, in this invention, the value of the surface resistivity and volume resistivity of each layer is the value measured based on JISK7194, Specifically, it means the value measured by the method described in the Example.

[Conductive Adhesive Sheet]

The electroconductive adhesive sheet of this invention has an adhesive conductive layer (X) and a non-stick conductive layer (Y) at least.

By providing the non-adhesive conductive layer (Y) in the electroconductive adhesive sheet of this invention, the surface resistivity of the adhesive conductive layer (X) falls significantly, and can improve antistatic property and electroconductivity. 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 good adhesive strength.

In the present invention, "tacky conductive layer (X)" and "non-tacky conductive layer (Y)" are distinguished by the presence or absence of adhesiveness, and the presence or absence of adhesiveness is the peak of the probe tack to the surface of each conductive layer It is judged from the value of the top.

That is, in the present invention, if the value of the peak top of the probe tack with respect to the surface of the conductive layer as a target is 0.1N or more, the conductive layer is judged to have adhesiveness, and is classified as "adhesive conductive layer (X)" do.

Conversely, if the value of the peak top of the probe tack with respect to the surface of the target conductive layer is less than 0.1N, the conductive layer is judged to be non-tacky, and is classified as a "non-tacky conductive layer (Y)".

In addition, the value of the peak top of the probe tack with respect to the surface of the target conductive layer is a value measured based on JIS Z 0237 (1991), Specifically, the value measured by the method described in the Example mentioned later it means.

The electroconductive adhesive sheet of this invention will not have a restriction|limiting in particular, if it is a structure which has an adhesive conductive layer (X) and a non-stick conductive layer (Y) at least, You may have other layers other than these.

Further, the conductive adhesive sheet of one embodiment of the present invention may have a configuration in which other layers are provided between the adhesive conductive layer (X) and the non-stick conductive layer (Y), but the surface resistivity of the conductive adhesive sheet is lowered, It is preferable that it is the structure in which the adhesive conductive layer (X) and the non-stick conductive layer (Y) were laminated|stacked directly from a viewpoint of improving prevention property and electroconductivity.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the electroconductive adhesive sheet which has a base material which is a structure of one suitable embodiment of the electroconductive adhesive sheet of this invention.

As a conductive adhesive sheet of one embodiment of the present invention, for example, as shown in FIG. ) is laminated in this order, and 1 A of conductive adhesive sheets are mentioned. This conductive adhesive sheet 1A has a two-layer body 21 composed of a non-stick conductive layer (Y) 12 and an adhesive conductive layer (X) 11 on one side of a base material.

Further, with respect to the configuration of the conductive adhesive sheet 1A, the conductive adhesive sheet 1B as shown in Fig. 1(b) in which a release sheet 14 is further laminated on the adhesive conductive layer (X) 11. can be done with

Moreover, as an electroconductive adhesive sheet of one embodiment of the present invention, for example, as shown in FIGS. ) may be an electrically conductive pressure-sensitive adhesive sheet having two-layer bodies 21a and 21b, respectively.

That is, the conductive adhesive sheet 2A shown in FIG. ), on the other side of the substrate 13, a second non-stick conductive layer (Y-II) (12b) and a second adhesive conductive layer (X-II) ( 11b) has a second two-layer body 21b.

In addition, the conductive adhesive sheet 2B shown in Fig. 1(d) is, with respect to the configuration of the conductive adhesive sheet 2A, on the first adhesive conductive layer (X-I) 11a and on the second adhesive conductive layer (X- II) It has the structure which further laminated|stacked the release sheets 14a, 14b on 11b, respectively.

Moreover, FIG. 2 is sectional drawing of the electroconductive adhesive sheet without a base material which is a structure of one suitable embodiment of the electroconductive adhesive sheet of this invention.

As an electroconductive adhesive sheet of one embodiment of the present invention, an electroconductive adhesive sheet without a base material may be used, and specifically, as shown in FIG. (Y) The electroconductive adhesive sheet 3 which has the structure which pinched|interposed the two-layer body 21 comprised by 12 with the release sheets 14a, 14b of 2 sheets is mentioned.

Further, as the conductive adhesive sheet of one embodiment of the present invention, as shown in Fig. 2(b), the first adhesive conductive layer (X-I) 11a, the non-stick conductive layer (Y) 12 and the second The conductive adhesive sheet 4 having a configuration in which the three-layer body 22 in which the adhesive conductive layers (X-II) 11b are laminated in this order is sandwiched by two release sheets 14a and 14b may be used.

As a conductive adhesive sheet of one embodiment of the present invention having a structure other than the above, a two-layer body composed of an adhesive conductive layer (X) and a non-stick conductive layer (Y) is subjected to adhesive conduction on one side of the peeling sheet on both sides of which has been subjected to peeling treatment. The electroconductive adhesive sheet etc. which have a structure wound in roll shape what provided so that layer (X) might be exposed are also 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 or layers formed of different adhesive compositions.

Similarly, the first non-tacky conductive layer (Y-I) 12a and the second non-tacky conductive layer (Y-II) 12b may be a layer formed of the same forming material or a layer formed of a different forming material. .

Hereinafter, the adhesive conductive layer (X), the non-stick conductive layer (Y), the base material, and the peeling sheet which comprise the electroconductive adhesive sheet of this invention are demonstrated.

In the present invention, the constitution of the first adhesive conductive layer (X-I) and the second adhesive conductive layer (X-II) is the same as that of the adhesive conductive layer (X), and the first non-stick conductive layer (Y-I) and the second adhesive conductive layer (X-I) 2 The configuration of the non-tacky conductive layer (Y-II) is the same as that of the non-tacky conductive layer (Y).

[Adhesive conductive layer (X)]

The adhesive conductive layer (X) of the conductive adhesive sheet of the present invention is a layer formed of a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive resin (x1) and a carbon-based filler (x2) having an average aspect ratio of 1.5 or more.

The adhesive conductive layer (X) has adhesiveness (the value of the peak top of the probe tack described above is 0.1N or more), and also has conductivity (the volume resistivity (ρ _VX ) of the layer alone is 1.0×10 ⁸ Ω·cm or less) is the floor

The surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is preferably 1.0×10 ² to 1.0×10 ¹⁰ Ω/□ from the viewpoint of providing a conductive adhesive sheet having good adhesive strength and effectively reducing the surface resistivity. , more preferably 1.0×10 ² to 1.0×10 ⁸ Ω/□, more preferably 1.0×10 ² to 1.0×10 ⁷ Ω/□, still more preferably 1.0×10 ² to 1.0×10 ⁶ Ω It is /□.

The volume resistivity (ρ _VX ) of the adhesive conductive layer (X) alone is preferably 1.0×10 ⁰ to 1.0×10 ⁸ Ω·cm from the viewpoint of providing a conductive adhesive sheet having good adhesive strength and effectively reducing the surface resistivity. , more preferably 1.0×10 ⁰ to 1.0×10 ⁶ Ω·cm, more preferably 1.0×10 ⁰ to 1.0×10 ⁵ Ω·cm, still more preferably 1.0×10 ⁰ to 1.0×10 ⁴ Ω ·cm.

The thickness (t _X ) of the adhesive conductive layer (X) is suitably adjusted according to the use, etc., Preferably it is 1-1200 micrometers, More preferably, it is 2-600 micrometers, More preferably, it is 3-300 micrometers, More preferably 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 adhesive force that does not depend on the type of the adherend can be expressed. On the other hand, the electroconductivity of the electroconductive adhesive sheet obtained as thickness ( _tX ) is 1200 micrometers or less becomes favorable. Moreover, when the said electroconductive adhesive sheet is made into a wound body, the bad effect that winding shift by the adhesive conductive layer (X) deform|transforms and the adhesive conductive layer (X) protrudes from the edge part of a wound body can be suppressed.

The pressure-sensitive adhesive composition as a material for forming the pressure-sensitive adhesive conductive layer (X) includes a pressure-sensitive adhesive resin (x1) and a carbon-based filler (x2) having an average aspect ratio of 1.5 or more, depending on the type of the pressure-sensitive adhesive resin (x1), a crosslinking agent or a tackifier , you may contain general-purpose additives other than these.

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 an adhesive conductive layer (X) means resin which has adhesiveness with a mass average molecular weight of 10,000 or more.

As a mass average molecular weight (Mw) of adhesive resin (x1), from a viewpoint of improving the adhesive force of an electroconductive adhesive sheet, Preferably it is 10,000-2 million, More preferably, it is 20,000-1,500,000.

The content of the adhesive resin (x1) in the adhesive composition is preferably 60.0 to 99.99% by mass, more preferably 70.0 to 99.9% by mass, still more preferably 80.0 to It is 99.5 mass %, More preferably, it is 90.0-99.0 mass %.

As the adhesive resin (x1), an acrylic resin, a urethane-based resin, a polyisobutylene-based resin, a styrene-based resin, a polyester-based resin, and a polyolefin from the viewpoint of improving the adhesive force of the conductive adhesive sheet and improving antistatic properties and conductivity It is preferable to include one or more adhesive resins selected from the group consisting of a resin-based resin, and one or more adhesive resins selected from the group consisting of acrylic resins, urethane-based resins, polyisobutylene-based resins and styrene-based resins. More preferably, at least one adhesive resin selected from the group consisting of an acrylic resin and a urethane-based resin is further preferably included.

(Acrylic resin)

As an acrylic resin that can be used as the adhesive resin (x1), for example, a polymer having a structural unit derived from an alkyl (meth) acrylate having a linear or branched alkyl group, derived from (meth) acrylate having a cyclic structure and a polymer having a structural unit to be mentioned.

The mass average molecular weight (Mw) of the acrylic resin is preferably 50,000 to 1.5 million, more preferably 150,000 to 1.3 million, still more preferably 250,000 to 1.1 million, still more preferably 350,000 to 900,000. .

Among the acrylic resins, the structural unit (a1) and the functional group-containing monomer (a2') derived from the alkyl (meth)acrylate (a1') having an alkyl group having 1 to 20 carbon atoms (hereinafter also referred to as "monomer (a1')") ) (hereinafter also referred to as "monomer (a2')"), an acrylic copolymer having a structural unit (a2) is preferable.

Moreover, the said acrylic copolymer may have a structural unit (a3) derived from monomers (a3') other than monomers (a1') and (a2').

In addition, the form of copolymerization of the said acrylic copolymer is not specifically limited. That is, as the said acrylic 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 the improvement of an adhesive characteristic, 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 (meth)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, and still more preferably 70 to It is 97 mass %, More preferably, it is 80-95 mass %.

Examples of the monomer (a2') include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an epoxy group-containing monomer, an amino group-containing monomer, a cyano group-containing monomer, a keto group-containing monomer, and an alkoxysilyl group-containing monomer.

Among these monomers (a2'), a carboxyl group-containing monomer is preferable.

As a carboxyl group-containing monomer, (meth)acrylic acid, a maleic acid, a fumaric acid, itaconic acid, etc. are mentioned, (meth)acrylic acid is preferable.

The content of the structural unit (a2) is preferably 0.5 to 50 mass%, more preferably 1 to 40 mass%, still more preferably 5 to 50 mass%, based on all the constituent units (100 mass%) of the acrylic copolymer. 30 mass %, More preferably, it is 7-20 mass %.

As the monomer (a3'), for example, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) (meth)acrylate, vinyl acetate, acrylonitrile, styrene, etc. which have cyclic structures, such as acrylate, dicyclopentenyloxyethyl (meth)acrylate, and imide (meth)acrylate, are mentioned.

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 10 with respect to all the structural units (100% by mass) of the acrylic copolymer. It is mass %, More preferably, it is 0-5 mass %.

In addition, you may use the above-mentioned monomers (a1') - (a3') individually or in combination of 2 or more type, respectively.

(urethane-based 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 chain, for example, obtained by reacting a polyol with a polyvalent isocyanate compound. The urethane-based prepolymer (?) and the urethane-based polymer (?) obtained by further subjecting the urethane-based prepolymer (?) to a chain extension reaction using a chain extender are mentioned.

Among these, it is preferable that the urethane-type polymer which has a polyoxyalkylene skeleton is included as a urethane-type resin used by one aspect of this invention.

The mass average molecular weight (Mw) of the urethane resin is preferably 10,000 to 200,000, more preferably 120,000 to 150,000, still more preferably 15,000 to 100,000, still more preferably 20,000 to 70,000. .

Examples of the polyol used as the raw material of the urethane-based prepolymer (α) include polyol compounds such as alkylenediol, polyether-type polyol, polyester-type polyol, and polycarbonate-type polyol. It may not be used, but may be a bifunctional diol or a trifunctional triol.

Among these polyols, diol is preferable from the viewpoints of availability, reactivity, and the like.

Examples of the diol include alkanediol such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, and ethylene glycol. , alkylene glycols such as 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 there is. In addition, these diols may be used individually or in combination of 2 or more types.

Among these diols, when further reacting with a chain extender, from the viewpoint of suppressing gelation in the reaction, glycol having a mass average molecular weight of 1000 to 3000 is preferable.

Examples of the polyvalent isocyanate compound used as a raw material for the urethane-based prepolymer (?) include aromatic polyisocyanate, aliphatic polyisocyanate, and alicyclic polyisocyanate.

Examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4- TDI), 2,6-tolylene diisocyanate (2,6-TDI), 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine di Isocyanate, 4,4'-diphenyl ether diisocyanate, 4,4',4"-triphenylmethane triisocyanate, 1,4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate, etc. can be heard

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, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, etc. are mentioned.

As alicyclic polyisocyanate, for example, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI), 1, 3- cyclopentane diisocyanate, 1, 3- cyclohexane diisocyanate, 1, 4- Cyclohexanediisocyanate, methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 4,4'-methylenebis(cyclohexylisocyanate), 1,4-bis(isocyanatemethyl)cyclo Hexane, 1, 4-bis (isocyanate methyl) cyclohexane, etc. are mentioned.

Moreover, the modified body of the compound (polyisocyanate) chosen from the aromatic polyisocyanate, aliphatic polyisocyanate, and alicyclic polyisocyanate mentioned above may be sufficient as a polyhydric isocyanate compound. Specifically, a trimethylolpropane adduct-type modified product of the compound, a biuret-type modified product obtained by reacting the compound with water, or an isocyanurate-type modified product containing an isocyanurate ring in the compound may be used.

Among these polyvalent isocyanate compounds, 4,4'-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolyl from the viewpoint of obtaining a urethane-based polymer excellent in adhesiveness At least one selected from rendiisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI) and modified products thereof is preferable , from the viewpoint of weather resistance, at least one selected from HMDI, IPDI, and modified products thereof is more preferable.

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

As the chain extender, a compound having two at least one of a hydroxyl group and an amino group, or a compound having three or more of at least one of a hydroxyl group and an amino group is preferable.

As the compound having at least one of two of a hydroxyl group and an amino group, at least one compound selected from the group consisting of aliphatic diols, aliphatic diamines, alkanolamines, bisphenols and aromatic diamines is preferable.

Examples of the aliphatic diol include alkanediol such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and 1,7-heptanediol, ethylene Alkylene glycol, such as glycol, propylene glycol, diethylene glycol, and dipropylene glycol, is mentioned.

Examples of the aliphatic diamine include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexanediamine.

As an alkanolamine, monoethanolamine, monopropanolamine, isopropanolamine, etc. are mentioned, for example.

As bisphenol, bisphenol A etc. are mentioned, for example.

Examples of the aromatic diamine include diphenylmethanediamine, tolylenediamine, and xylylenediamine.

Examples of the compound having three or more of 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 and amino alcohols such as -methylamino-2,3-propanediol and N-(2-hydroxypropylethanolamine), and ethylene oxide or propylene oxide adducts of tetramethylxylylenediamine.

(Polyisobutylene-based resin)

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

The mass average molecular weight (Mw) of the PIB-based resin is preferably 20,000 or more from the viewpoint of sufficiently obtaining the cohesive force of the resulting adhesive composition, improving the adhesive force of the conductive adhesive sheet and preventing contamination of the adherend, and From the viewpoint of wettability to an adherend or solubility in a solvent, it is preferably 30,000 to 1,000,000, more preferably 50,000 to 800,000, still more preferably 70,000 to 600,000.

Examples of the PIB-based resin include polyisobutylene, which is a homopolymer of isobutylene, a copolymer of isobutylene and isoprene, a copolymer of isobutylene and n-butene, a copolymer of isobutylene and butadiene, and The halogenated butyl rubber etc. which carried out bromination, chlorination, etc. of these copolymers are mentioned.

Moreover, when PIB-type resin is a copolymer, the structural unit derived from isobutylene is contained most in all the structural units.

In the PIB-based resin used in one embodiment of the present invention, the content of the structural unit derived from isobutylene is preferably 80 to 100% by mass with respect to all the structural units (100% by mass) of the PIB-based resin. , More preferably, it is 90-100 mass %, More preferably, it is 95-100 mass %, More preferably, it is 98-100 mass %.

These PIB-type resin may be used independently and may be used in combination of 2 or more type.

Among these, from the viewpoint of improving the durability and weather resistance of the adhesive conductive layer (X) to be formed, it has a dense molecular structure when polymerized, and has no polymerizable double bonds in the main chain and side chains, and is a structure derived from isobutylene. It is preferable to include many units.

In the PIB-based resin used in one embodiment of the present invention, the content of the structural unit derived from isobutylene in which a polymerizable double bond does not exist in such main chain and side chain is the total structural unit (100) of the PIB-based resin. to mass %), Preferably it is 80-100 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 a high mass average molecular weight, and PIB-type resin with a low mass average molecular weight.

More specifically, as the PIB-based resin used in one embodiment 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)”), and a mass It is preferable to use together PIB-type resin (p2) (henceforth "PIB-type resin (p2)") whose average molecular weights are 50,000-250,000.

PIB-type resin (p1) with a high mass average molecular weight contributes to improving adhesive force while improving the durability and weather resistance of the adhesive conductive layer (X) formed from the adhesive composition obtained.

In addition, the PIB-based resin (p2) having a low mass average molecular weight is compatible with the PIB-based resin (p1) well, and can appropriately plasticize the PIB-based resin (p1), and the adhesive conductive layer (X) is It improves the wettability to the complex and contributes to improving adhesive properties, flexibility, and the like.

From the above viewpoint, the mass average molecular weight (Mw) of the PIB-based resin (p1) is preferably 270,000 to 600,000, more preferably 290,000 to 480,000, still more preferably 310,000 to 450,000, further Preferably it is 320,000 - 400,000.

From the above viewpoint, the mass average molecular weight (Mw) of the PIB-based resin (p2) is preferably 50,000 to 250,000, more preferably 80,000 to 230,000, still more preferably 140,000 to 220,000, further Preferably, it is 180,000 to 210,000.

Preferably the content rate of PIB-type resin (p2) with respect to 100 mass parts of PIB-type resin (p1) is 5-55 mass parts, More preferably, it is 6-40 mass parts, More preferably, it is 7-30 mass parts. , More preferably, it is 8-20 mass parts.

When the content ratio of the PIB-based resin (p2) is 5 parts by mass or more, the PIB-based resin (p1) can be sufficiently plasticized and the wettability of the formed adhesive conductive layer (X) to an adherend is improved. , the adhesive force can also be improved.

On the other hand, when 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 force, and durability can be improved.

(Styrenic resin)

The styrenic resin usable as the adhesive resin (x1) is a polymer having a structural unit derived from styrene.

Styrenic resin used in one embodiment of the present invention WHEREIN: Content of the structural unit derived from styrene with respect to all the structural units (100 mass %) of the said styrenic resin, Preferably it is 5-50 mass %, More Preferably it is 10-40 mass %, More preferably, it is 15-35 mass %.

The mass average molecular weight (Mw) of the styrene-based resin is preferably 10,000 to 400,000, more preferably 20,000 to 300,000, still more preferably 25,000 to 20, from the viewpoint of improving the adhesive force of the conductive adhesive sheet. it's been awhile

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 force of the conductive adhesive sheet. to 135°C.

In addition, in this invention, the softening point of a styrene resin means the value measured based on JISK2531.

As the styrene-based resin, for example, a styrene-butadiene-styrene triblock copolymer (hereinafter also referred to as “SBS”), a styrene-block (block)-(ethylene-co-butylene)-block-styrene triblock copolymer (hereinafter also referred to as “SEBS”), styrene-block-(ethylene-co-butylene)-block diblock copolymer (hereinafter also referred to as “SEB”), styrene-butadiene diblock copolymer, styrene-isoprene diblock copolymer Block copolymer, styrene-isoprene-styrene triblock copolymer, styrene-block-(butadiene-co-isoprene)-block diblock copolymer, styrene-block-(butadiene-co-isoprene)-block-styrene triblock copolymer Copolymers, carboxyl-modified products of these copolymers, and copolymers of styrene and aromatic vinyl compounds such as α-methylstyrene, etc. are mentioned.

The said styrene resin may be used independently and may be used in combination of 2 or more type.

Among these styrene resins, SBS, SEBS, and SEB are preferable, and SBS and SEBS are more preferable.

In addition, when the said styrenic resin is a copolymer, the form of copolymerization is not specifically limited. That is, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient as the said styrenic resin.

(Polyester resin)

The polyester resin that can be used as the adhesive resin (x1) is a copolymer obtained by polycondensation reaction of an acid component and a diol component or a polyol component, and includes a modified product of the copolymer.

The said polycondensation reaction is performed by general polyesterification reactions, such as a direct esterification method and a transesterification method.

In addition, the form of copolymerization of the said polyester-type resin is not specifically limited. That is, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient as the said polyester-type resin.

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, suber aliphatic dicarboxylic acids such as acid, azelaic acid, sebacic acid, undecylenic acid, dodecanedicarboxylic acid, or esters thereof; Alicyclic dicarboxylic acids, such as 1, 4- cyclohexahydro phthalic anhydride, etc. are mentioned.

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, 1,6 -Hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, etc. and alicyclic glycols such as aliphatic glycol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol, and aromatic glycols such as bisphenol A.

In addition, the said polyester resin may be used independently and may be used in combination of 2 or more type.

(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 the polyolefin-based resin include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene and linear low-density polyethylene, polypropylene, a copolymer of ethylene and propylene, a copolymer of ethylene and another α-olefin, propylene and other α- copolymers of olefins, copolymers of ethylene and propylene and other α-olefins, copolymers of ethylene and other ethylenically unsaturated monomers (ethylene-vinyl acetate copolymer, ethylene-alkyl (meth)acrylate copolymer, etc.) can

In addition, when the said polyolefin resin is a copolymer, the form of copolymerization is not specifically limited. That is, as the said polyolefin resin, any of a block copolymer, a random copolymer, and a graft copolymer may be sufficient.

Examples of the α-olefin include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

As said ethylenically unsaturated monomer, vinyl acetate, (meth)acrylic acid, an 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, a copolymer of ethylene and propylene, and a copolymer of propylene and another α-olefin, are preferable.

In addition, the said polyolefin resin may be used independently and may be used in combination of 2 or more type.

<Carbon-based filler (x2)>

The pressure-sensitive adhesive composition, which is a material for forming the pressure-sensitive adhesive conductive layer (X), includes a carbon-based filler (x2) having an average aspect ratio of 1.5 or more together with the pressure-sensitive adhesive resin (x1).

When the average aspect ratio of the carbon-based filler (x2) is less than 1.5, the surface resistivity of the formed adhesive conductive layer (X) tends to be high, and even a conductive adhesive sheet provided with a non-stick conductive layer (Y) has a sufficient surface. It is difficult to lower the resistivity, and thus the antistatic properties and conductivity are poor.

The average aspect ratio of the carbon-based filler (x2) is preferably 2 to 10000, more preferably 3 to 5000, from the viewpoint of lowering the surface resistivity of the adhesive conductive layer (X) to be formed and improving the adhesive strength, More preferably, it is 4-1000, More preferably, it is 5-500, More preferably, it is 6-400, More preferably, it is 10-300.

In the present invention, "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 side length (L) It is a value calculated from '. In addition, an "average aspect ratio" is an average value of the said "aspect ratio" calculated for 10 target carbon-based fillers.

In addition, the length H of the long side of the carbon-based filler (x2) means the length of the target carbon-based filler in the height direction (length direction).

On the other hand, the length L of the short side of the carbon-based filler (x2) is a diameter or a long diameter if the cross-section is a circle or an ellipse in a cut plane orthogonal to the height direction (length direction) of the target carbon-based filler, If the cross section is a polygon, the diameter of the circumscribed circle of the polygon is indicated.

The length (H) of the long side 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, even more preferably 0.10 to 100 µm. .

Further, in the present invention, the average value of the lengths of the long sides of ten arbitrarily selected carbon-based fillers may be regarded as the value of the above-mentioned "length of long sides (H) of carbon-based fillers (x2)".

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, still more preferably 3 to 500 nm, still more preferably 5 to 100 nm, more More preferably, it is 7-50 nm.

Further, in the present invention, the average value of the lengths of the short sides of ten arbitrarily selected carbon-based fillers may be regarded as the value of the "length of the short sides (L) of the carbon-based fillers (x2)".

Examples of the shape of the carbon-based filler (x2) include a columnar shape, a cylindrical shape, a pendulum shape, a fibrous shape, a spherical shape (sphericity is usually 0.7 or less), a shape combining these, and the like.

Among these shapes, from the viewpoint of forming the adhesive conductive layer (X) having good conductivity, at least one selected from a columnar carbon-based filler, a cylindrical carbon-based filler, and a fibrous carbon-based filler is preferable.

The content of the carbon-based filler (x2) in the adhesive composition is 0.01 to 15 parts by mass, preferably 0.02 to 10 parts by mass, more preferably 0.30 to 7.0 parts by mass, with respect to 100 parts by mass of the adhesive resin (x1), More preferably, it is 0.40-5.0 mass parts, More preferably, it is 0.50-4.5 mass parts, More preferably, it is 0.70-3.8 mass parts.

When the content of the carbon-based filler (x2) is less than 0.01 parts by mass, the surface resistivity of the formed adhesive conductive layer (X) tends to increase, and even as a conductive adhesive sheet provided with a non-stick conductive layer (Y), it is sufficient It is difficult to reduce the surface resistivity, and the antistatic properties and conductivity are inferior.

On the other hand, when the content of the carbon-based filler (x2) exceeds 15 parts by mass, the adhesive force of the formed adhesive conductive layer (X) tends to decrease.

Further, in the conductive adhesive sheet of the present invention, when the content of the carbon-based filler (x2) in the adhesive conductive layer (X) is at least, excellent antistatic properties and conductivity are expressed, so it is necessary to mix a large amount of the carbon-based filler (x2) there is no

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

Examples of the carbon-based filler (x2) include carbon nanomaterials, carbon black, pulverized carbon fibers, graphite, and the like. From the viewpoint, carbon nanomaterials are preferable.

Carbon nanomaterials include substances containing graphite sheets having a six-membered ring arrangement as the main structure, but may contain elements other than carbon such as boron and nitrogen in the graphite structure, and carbon nanomaterials are different The form may be included, or the form in which the carbon nanomaterial is modified by another conductive substance may be sufficient.

Examples of the carbon nanomaterial include carbon nanotube (CNT), carbon nanofiber, carbon nanohorn, carbon nanocone, fullerene, and the like, and carbon nanotube is preferable.

A carbon nanotube is a cylindrical carbon polyhedron having a structure in which a graphite (graphite) sheet having a carbon 6-membered ring structure as a main structure is closed in a cylindrical shape.

Carbon nanotubes include single-walled carbon nanotubes having a structure in which one layer of graphite sheets are closed in a cylindrical shape, two-walled carbon nanotubes having a structure in which two layers of graphite sheets are closed in a cylindrical shape, and three or more graphite sheets There are multi-walled carbon nanotubes having a multilayer structure closed in a concentric tubular shape, and any two or more of them may be used in combination.

<crosslinking agent>

The adhesive composition which is a forming material of an adhesive conductive layer (X) may further contain a crosslinking agent.

In particular, in the case of using the above-mentioned acrylic resin (in particular, the acrylic copolymer having the above-described structural unit (a2)) as the adhesive resin (x1), from the viewpoint of improving the adhesive strength of the adhesive conductive layer (X) to be formed , 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. You may use these crosslinking agents individually or in combination of 2 or more types.

Among these, an isocyanate type crosslinking agent is preferable from a viewpoint of improving the adhesive force of an electroconductive adhesive sheet.

Examples of the isocyanate-based crosslinking agent include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, and diphenylmethane-4,4' -Diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclo Polyvalent isocyanate compounds, such as hexylmethane-2,4'- diisocyanate and lysine isocyanate, are mentioned.

Moreover, the trimethylolpropane adduct-type modified body of the said compound, the biuret-type modified body made to react with water, and the isocyanurate-type modified body containing an isocyanurate ring may be sufficient as a polyhydric isocyanate compound.

To [ content of a crosslinking agent / 100 mass parts of adhesive resin (x1)), Preferably it is 0.01-15 mass parts, More preferably, it is 0.05-10 mass parts, More preferably, it is 0.1-5 mass parts.

<Tackifier>

The adhesive composition which is a forming material of an adhesive conductive layer (X) may contain a tackifier further.

In particular, in the case of using the above-mentioned urethane-based resin, PIB-based resin and styrene-based resin as the adhesive resin (x1), from the viewpoint of improving the adhesive force of the adhesive conductive layer (X) to be formed, containing a tackifier is preferred. desirable.

In addition, the mass average molecular weight (Mw) of this tackifier is less than 10,000 normally, and is distinguished from the adhesive resin (x1) mentioned above.

The mass average molecular weight (Mw) of a tackifier becomes like this. From a viewpoint of improving the adhesive force of the adhesive conductive layer (X) formed, Preferably it is 400-4000, More preferably, it is 800-1500.

As a softening point of a tackifier, Preferably it is 110 degreeC or more, More preferably, it is 110-180 degreeC, More preferably, it is 115-175 degreeC, More preferably, it is 120-170 degreeC.

In addition, in this invention, the "softening point" of a tackifier means the value measured based on JISK2531.

As a tackifier, For example, Rosin-type resin, such as a rosin resin, a rosin phenol resin, and its ester compound; hydrogenated rosin-based resins obtained by hydrogenating these rosin-based resins; terpene resins such as terpene resins, aromatic modified terpene resins and terpene phenol resins; hydrogenated terpene resins obtained by hydrogenating these terpene-based resins; C5-type petroleum resin obtained by copolymerizing C5 fractions, such as pentene, isoprene, piperine, and 1.3-pentadiene, produced by thermal decomposition of petroleum naphtha, and hydrogenated petroleum resin of this C5-type petroleum resin; C9-based petroleum resins obtained by copolymerizing C9 fractions such as indene, vinyltoluene, α- or β-methylstyrene produced by thermal decomposition of petroleum naphtha, and hydrogenated petroleum resins of this C9-based petroleum resin; and the like.

In addition, in this invention, a tackifier may be used individually or in combination of 2 or more types from which a softening point or structure differs.

To [ content of a tackifier / 100 mass parts of adhesive resin (x1) ], Preferably it is 1-200 mass parts, More preferably, it is 5-160 mass parts, More preferably, it is 10-120 mass parts.

Moreover, when the adhesive resin (x1) contains an acrylic resin, content of the said tackifier with respect to 100 mass parts of acrylic resins, Preferably it is 1-100 mass parts, More preferably, it is 5-50 mass parts, More preferably, it is 10-40 mass parts.

When the adhesive resin (x1) contains a urethane resin, content of the said tackifier becomes like this with respect to 100 mass parts of urethane resin, Preferably it is 5-200 mass parts, More preferably, it is 40-160 mass parts, More preferably It is preferably 80 to 120 parts by mass.

When adhesive resin (x1) contains PIB-type resin, content of the said tackifier becomes like this with respect to 100 mass parts of PIB-type resin, Preferably it is 5-100 mass parts, More preferably, it is 10-80 mass parts, More preferably, it is 15-40 mass parts.

When the adhesive resin (x1) contains a styrenic 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 styrenic resin, More preferably, it is 25-60 mass parts.

When the adhesive resin (x1) contains a polyester resin, content of the said tackifier becomes like this with respect to 100 mass parts of polyester resin, Preferably it is 5-100 mass parts, More preferably, it is 15-80 mass part, More preferably, it is 25-60 mass parts.

When the adhesive resin (x1) contains a polyolefin-based 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-based resin, More preferably, it is 25-60 mass parts.

<Other additives>

The adhesive composition which is a forming material of an adhesive conductive layer (X) may contain the general-purpose additive generally used with adhesive resin in the range which does not impair the effect of this invention.

Examples of such general-purpose additives include ultraviolet absorbers, antioxidants, softeners (plasticizers), fillers, rust inhibitors, pigments, dyes, curing agents, curing aids, and catalysts.

When mix|blending these general-purpose additives, each compounding quantity of a general-purpose additive is with respect to 100 mass parts of adhesive resin (x1), Preferably it is 0.01-6 mass parts, More preferably, it is 0.01-2 mass parts.

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 as the material for forming the adhesive conductive layer (X) is preferably 20% by mass or more, more preferably 30% by mass % or more

In the case of using the adhesive resin (x1) containing an acrylic 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 60% by mass More 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 the adhesive resin (x1) containing a urethane-based 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 35% by mass or more, More preferably, it is 40 mass % or more, More preferably, it is 45 mass % or more, The total content of adhesive resin (x1), carbon-type filler (x2), and a tackifier becomes like this. Preferably it is 70 mass % or more, More preferably is 80 mass % or more, More preferably, it is 90 mass % or more.

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

When the adhesive resin (x1) containing a styrene resin as a main component is used, 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 20% by mass or more , More preferably, it is 25 mass % or more, More preferably, it is 30 mass % or more.

In addition, the notation "adhesive resin (x1) containing a ZZ-type resin as a main component" means that "the content of the ZZ-type resin is the highest among the resins contained in the adhesive resin (x1)".

As a specific content of ZZ-type resin in the said base material, with respect to the whole amount (100 mass %) of adhesive resin (x1), 50 mass % or more normally, Preferably it is 65-100 mass %, More preferably, it is 75-100 mass %. It is mass %, More preferably, it is 85-100 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 methods (X-1) and (X-2) are mentioned.

Method (X-1): Prepare an organic solvent solution of the pressure-sensitive adhesive composition, apply the solution on a release sheet to be described later by a known coating method to form a coating film, and dry the coating film to form an adhesive conductive layer (X) how to form

Method (X-2): After heat-kneading the adhesive resin (x1) and the carbon-based filler (x2) to prepare a composite, the composite is molded into a sheet by a known molding method, and the adhesive A method of forming the conductive layer (X).

(Method (X-1))

Method (X-1) is a formation method suitable when an acrylic resin, a urethane-type resin, a PIB-type resin, etc. are used as an adhesive resin (x1).

In the method (X-1), examples of the organic solvent used include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexane, n-hexane, toluene, xylene, n-propanol, isopropanol. , dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, and the like.

In addition, as these organic solvents, you may use the organic solvent used at the time of the synthesis|combination of adhesive resin (x1) 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 adhesive resin (x1) in a low-viscosity state, so that the carbon-based fillers (x2) easily come into contact with each other and a network of fillers is formed, The surface resistivity and volume resistivity of the adhesive conductive layer (X) which are formed fall easily.

As a solvent used for manufacture of the dispersion liquid of a carbon-type filler (x2), water or the organic solvent mentioned above is mentioned, An organic solvent is preferable.

As a manufacturing method of the dispersion liquid of a carbon-type filler (x2), the method of adding a carbon-type filler (x2) to a solvent, and giving vibration for a fixed period of time by ultrasonic waves etc. are mentioned, for example.

The solid content concentration of the dispersion of the carbon-based filler (x2) is preferably 0.01 to 60 mass %, more preferably 0.05 to 10 mass %, still more preferably 0.1 to 3 mass %.

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

Moreover, after apply|coating the solution of an adhesive composition on a release sheet to form a coating film, it is preferable to dry-process and to remove the solvent contained in a coating film.

In addition, in the method (X-1), in order to improve the adhesive force, the applied layer after the drying treatment is left still for about 7 to 30 days under an environment of, for example, 23 ° C. and 50% RH (relative humidity), It is preferable to sufficiently crosslink the inside of the coating layer.

(Method (X-2))

Method (X-2) is a suitable forming method when using a resin durable to heat kneading, such as a styrenic resin, as the adhesive resin (x1).

As a heat-kneading apparatus, a single screw extruder, a twin screw extruder, a roll mill, a plastomer, a Banbury mixer, an intermix, a pressure kneader, etc. are mentioned, for example.

As a method of shaping|molding the composite obtained by the said heat-kneading apparatus, a melt extrusion method, a calendering method, the compression molding method etc. are mentioned, for example, The compression molding method is preferable.

As a specific method of the compression molding method, the sheet-like adhesive conductive layer (X) can be molded by sandwiching the manufactured composite between two release sheets and heating and compressing it with a hot press machine or the like. In addition, instead of the release sheet of 2 sheets, you may sandwich the composite manufactured by the base material and the release sheet, and you may shape|mold the sheet-like adhesive conductive layer (X).

[Non-tacky conductive layer (Y)]

The non-adhesive conductive layer (Y) of the conductive pressure-sensitive adhesive sheet of the present invention is a non-adhesive layer (the value of the peak top of the probe tack described above is less than 0.1N), and the conductivity (the volume resistivity of the layer alone (ρ _VX ) is 1.0×10 ⁸ Ω·cm or less).

The surface resistivity (ρ _SY ) of the non-adhesive conductive layer (Y) alone is preferably 1.0×10 ⁻² to 1.0×10 ⁸ Ω/□, more preferably from the viewpoint of forming a conductive pressure-sensitive adhesive sheet with effectively reduced surface resistivity. preferably 1.0×10 ^-2 to 1.0×10 ⁷ Ω/□, more preferably 1.0×10 ^-2 to 1.0×10 ⁶ Ω/□, even more preferably 1.0×10 ^-2 to 1.0×10 ⁵ Ω/□ □, 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/□.

In one embodiment of 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-stick conductive layer (Y) alone is the surface resistivity of the adhesive conductive layer (X) alone It is preferable that it is a value smaller than (ρ _SX ).

The volume resistivity (ρ _VY ) of the non-adhesive conductive layer (Y) alone is preferably 1.0×10 ⁻⁴ to 1.0×10 ⁶ Ω·cm, more preferably from the viewpoint of forming a conductive pressure-sensitive adhesive sheet with effectively reduced surface resistivity. preferably 1.0×10 ^-4 to 1.0×10 ⁴ Ω·cm, more preferably 1.0×10 ^-4 to 1.0×10 ³ Ω·cm, more preferably 1.0×10 ^-4 to 1.0×10 ² Ω·cm cm, more preferably 1.0×10 ⁻⁴ to 1.0×10 ¹ Ω·cm, and still more preferably 1.0×10 ⁻⁴ to 1.0×10 ⁰ Ω·cm.

Further, in one embodiment of the present invention, from the viewpoint of effectively reducing the surface resistivity of the conductive adhesive sheet, the volume resistivity (ρ _VY ) of the non-stick conductive layer (Y) alone is the volume resistivity of the adhesive conductive layer (X) alone It is preferable that the value is smaller than (ρ _VX ).

The thickness (t _Y ) of the non-tacky conductive layer (Y) is appropriately adjusted depending on the use, etc., preferably 0.01 to 200 µm, more preferably 0.1 to 160 µm, still more preferably 0.5 to 130 µm, further Preferably it is 1.0-100 micrometers.

When the thickness (t _Y ) is 0.01 µm or more, the surface resistivity of the non-tacky conductive layer (Y) can be effectively reduced.

On the other hand, when the thickness (t _Y ) is 200 µm or less, when the conductive adhesive sheet is made into a wound body, the non-adhesive conductive layer (Y) is deformed due to winding deviation, and the non-adhesive conductive layer (Y) is formed from the end of the wound body. I can suppress the evil that it protrudes. Moreover, by making the total thickness of an electroconductive adhesive sheet small, it can be set as the electroconductive adhesive sheet which is easy to apply to a small electronic device.

In the present invention, the non-stick conductive layer (Y) is a layer containing at least one conductive material selected from the group consisting of a conductive polymer, a carbon-based filler, and a metal oxide.

Since the non-adhesive conductive layer (Y) is a layer containing these specific conductive materials, the surface resistivity of the adhesive conductive layer (X) can be remarkably reduced.

In addition, from the above viewpoint, the non-stick conductive layer (Y) preferably contains at least one conductive material selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials, and ITO (indium tin oxide), It is more preferable to include at least one conductive material 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 2.0 g/cm 3 , still more preferably 0.8 from the viewpoint of weight reduction of the conductive adhesive sheet. to 1.7 g/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, and polyquinoxaline.

Among these, polythiophene and PEDOT-PSS are preferable.

The non-adhesive conductive layer (Y) containing a conductive polymer preferably contains a non-tacky resin together with the conductive polymer, and as the non-tacky resin, one selected from an acrylic resin, a urethane resin, a PIB resin, and a styrene resin The above non-tacky resin is preferable.

When using a conductive polymer as an electrically-conductive material, content of a conductive polymer becomes like this with respect to the whole quantity (100 mass %) of a non-stick conductive layer (Y), Preferably it is 4-100 mass %, More preferably, it is 8-100 mass %am.

There is no restriction|limiting in particular as a formation method of the non-adhesive conductive layer (Y) containing a conductive polymer, For example, a solution of the organic solvent containing a conductive polymer is prepared, and the said solution is well-known application|coating on a base material or a release sheet. The method of apply|coating by a method, forming a coating film, drying a coating film, and forming is mentioned.

About the kind of organic solvent used for the said method, and the application|coating method of a solution, it is the same as that of description regarding "method (X-1)" which is a formation method of the above-mentioned adhesive conductive layer (X).

<Carbon-based filler>

Examples of the carbon-based filler include those similar to those of the carbon-based filler (x2) described above, and carbon nanomaterials are preferable.

The non-adhesive conductive layer (Y) containing the carbon-based filler preferably contains a non-tacky resin together with the carbon-based filler, and the non-adhesive resin is selected from an acrylic resin, a urethane-based resin, a PIB-based resin, and a styrene-based resin. At least one non-tacky resin is preferred.

When a carbon-based filler is used as the conductive material, the content of the carbon-based filler is preferably 0.1 to 20% by mass, more preferably 0.5 to the total amount (100% by mass) of the non-tacky conductive layer (Y). -15 mass %, More preferably, it is 1.0-10 mass %, More preferably, it is 2.0-7 mass %.

The method for forming the non-stick conductive layer (Y) containing the carbon-based filler is not particularly limited, and for example, a dispersion of a carbon-based filler and a solution of an organic solvent of a non-adhesive resin are mixed to obtain a solution of the resin composition. After manufacture, the said solution is apply|coated by a well-known coating method on a base material or a release sheet, the method of forming a coating film is mentioned, The method of drying and forming a coating film is mentioned.

Regarding the type of organic solvent used in the method, the method for preparing the dispersion liquid of the carbon-based filler, and the method for applying the solution, the description of “Method (X-1)” as the method for forming the adhesive conductive layer (X) described above; The same is true.

In addition, as a method of forming the non-stick conductive layer (Y) containing the carbon-based filler, a composite is prepared by heating and kneading the carbon-based filler and the non-adhesive resin, and then the composite is formed into a sheet by a known molding method. The method may be obtained as a prize.

About the heat-kneading machine used for the said method, and the shaping|molding method of a composite, it is the same as that of description regarding "method (X-2)" which is the formation method of the above-mentioned adhesive conductive layer (X).

<Metal Oxide>

As a metal oxide, 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 (tin oxide) antimony) and the like.

Among these, ITO (indium tin oxide) is preferable.

Moreover, when using a metal oxide as an electrically-conductive material, it is preferable that a non-stick conductive layer (Y) is a layer containing only the said metal oxide.

Moreover, as a formation method of the non-tacky conductive layer (Y) containing a metal oxide, the method of forming by vapor deposition with respect to a base material is preferable.

[write]

The substrate used for the conductive adhesive sheet of one embodiment of the present invention is appropriately selected depending on the use of the conductive adhesive sheet, and may be an insulating substrate containing an insulating material or a conductive substrate containing a conductive material such as a metal.

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 an insulating base material, For example, various papers, such as good quality paper, art paper, coated paper, glassine paper, etc., and laminated paper which laminated thermoplastic resin, such as polyethylene, on these paper base materials; porous materials such as nonwoven fabrics; a plastic film or sheet containing a polyolefin resin such as a polyethylene resin or a polypropylene resin, a polyester resin such as a polybutylene terephthalate resin or a polyethylene terephthalate resin, an acetate resin, an ABS resin, a polystyrene resin, or a vinyl chloride resin; a plastic film or sheet comprising a mixture of these resins; and a plastic film or sheet including a laminate of these plastic films or sheets.

In addition, the base material, such as a plastic film or a sheet|seat, may be unstretched, and may be extended|stretched in uniaxial directions, such as a lengthwise or horizontal direction, or a biaxial direction.

In addition, these insulating base materials (especially plastic films or sheets) may further contain a ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an anti-blocking agent, a colorant, and the like.

Examples of the conductive substrate include a metal foil, a film or sheet in which a metal foil is laminated with a resin or the like for forming the above-described insulating substrate, a film or sheet in which the surface of the above-described insulating substrate is subjected to metal vapor deposition, and on the surface of the above-described insulating substrate The film or sheet which performed the antistatic process, the sheet|seat etc. which knitted the metal wire in the mesh shape are mentioned.

Moreover, as a metal used for an electroconductive base material, aluminum, copper, silver, gold|metal|money 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, still more preferably 20 to 150 µm from the viewpoint of easy handling.

When the base material is a plastic film or sheet, from the viewpoint of improving the adhesion between the base material and the non-tacky conductive layer (Y), if necessary, the surface of the base material is preferably subjected to a surface treatment such as an oxidation method or an unevenness method.

The oxidation method is not particularly limited, and examples thereof include a corona discharge treatment method, a plasma treatment method, chromic acid oxidation (wet), a flame treatment, a hot air treatment, and an ozone/ultraviolet irradiation treatment. Moreover, it does not specifically limit as an unevenness|corrugation method, For example, the sandblasting method, the solvent treatment method, etc. are mentioned. Although these surface treatments are suitably selected according to the kind of base material, the corona discharge treatment method is preferable from the viewpoint of the improvement effect of adhesiveness with a non-stick conductive layer (Y), and operability. In addition, a primer treatment can also be performed.

[Peel Sheet]

In addition, as the release sheet used for the conductive pressure-sensitive adhesive sheet of one embodiment of the present invention, a release sheet subjected to double-sided release treatment, a release sheet subjected to single-sided release treatment, etc. are used, and a release agent coated on a base material for release sheet, etc. are mentioned. can

As a base material for release sheets, for example, paper base materials such as glassine paper, coated paper, and high quality paper, laminate paper obtained by laminating these paper base materials with a thermoplastic resin such as polyethylene, or polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene Plastic films, such as polyester resin films, such as a naphthalate resin, polyolefin resin films, such as a polypropylene resin and a polyethylene resin, are mentioned.

Examples of the release agent include rubber-based elastomers such as silicone-based resins, olefin-based resins, isoprene-based resins and butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, and fluorine-based resins.

Although the thickness in particular of a release sheet is not restrict|limited, Preferably it is 10-200 micrometers, More preferably, it is 25-150 micrometers.

[Method for manufacturing conductive adhesive sheet, physical properties]

The conductive adhesive sheet of one embodiment of the present invention can be produced by appropriately bonding the adhesive conductive layer (X) and the non-stick conductive layer (Y) formed by the above-described forming method, and a base material or a release sheet.

As a value of the peak top of a probe tack with respect to the surface of the adhesive conductive layer (X) which the electroconductive adhesive sheet of one embodiment of this invention has, Preferably it is 0.1N or more, More preferably, it is 0.1-49N, More preferably, 0.5- 49N, even more preferably 1.0-49N.

In addition, the value of the peak top of the said probe tag means the value measured by the method described in an Example. In addition, the value of the peak top of the said probe tack is a physical property value used as an adhesive force index|index of a conductive adhesive sheet, and 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 of one embodiment of the present invention is preferably 9.0×10 ⁴ Ω/□ or less, more preferably 1.0×10 ⁴ Ω/□ or less, more preferably 5.0×10 ³ Ω/□ or less, and still more preferably 2.0×10 ³ Ω/□ or less.

In addition, the value of the said "surface resistivity measured from the surface side of the adhesive conductive layer (X) which an electrically conductive adhesive sheet has" is at least the electroconductivity of the present invention in which the adhesive conductive layer (X) and the non-stick conductive layer (Y) are laminated. It is a value of the surface resistivity measured from the surface side of the adhesive conductive layer (X) exposed of the adhesive sheet, and is different from the value of the "surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone" described above.

Example

About the physical property of each component used by the following Example and the comparative example, and each physical property of an electroconductive adhesive sheet, an adhesive conductive layer (X), and a non-adhesive conductive layer, it measured by the method described below.

<Mass Average Molecular Weight (Mw)>

It measured under the following conditions using the gel permeation chromatography apparatus (The Tosoh Corporation make, product name "HLC-8020"), and the value measured by standard polystyrene conversion was used.

(Measuring conditions)

· Column: "TSK guard column HXL-H", "TSK gel GMHXL (x2)" and "TSK gel G2000HXL" (all manufactured by Tosoh Corporation) were sequentially connected.

·Column temperature: 40℃

·Developing solvent: tetrahydrofuran

·Flow rate: 1.0mL/min

<Aspect ratio of carbon-based filler, length of long side and short side>

Using a scanning electron microscope (manufactured by Hitachi High Technologies, Inc., product name "S-4700"), 10 randomly extracted carbon-based filler particles were observed, and the length of the long side and the length of the short side were measured. and the average value of 10 particles of the carbon-based filler was defined as the "long side length (H)" and "short side length (L)" of the filler. In addition, the aspect ratio (H/L) was computed from "long side length (H)/short side length (L)".

<Softening point>

It measured based on JISK2531.

<Density>

It measured based on JIS Z 8807:2012.

<Probe tag>

It measured based on JIS Z0237 (1991).

Specifically, a test piece having a size of 10 mm × 10 mm is left still for 24 hours in an environment of 23° C. and 50% RH (relative humidity), and then the surface of the layer to be measured of the test piece is exposed, and a tacking tester ( The Rigaku Kogyo Co., Ltd. make, product name "PROBE TACK TESTER") was used, and the probe tack value with respect to the surface of the said layer was measured.

In addition, the probe tack value is, after making a stainless steel probe having a diameter of 5 mm in contact with the surface of the layer to be measured at a contact load of 0.98 N/cm 2 for 1 second, the probe is separated from the surface at a speed of 600 mm/sec. The force required to do it was made into the surface probe tack value of the layer.

In addition, about the surface of a non-tacky conductive layer, the peak top of a probe tack value was measured. In addition, about the surface of the adhesive conductive layer (X) which an electroconductive adhesive sheet has, the peak top and integral value of a probe tack value were measured.

In addition, when there is no adhesiveness on the surface of the layer of a measurement object, and the peak top of a probe tack value was impossible to measure, the value of the said peak top was made into "0 (N)".

<Surface resistivity, volume resistivity>

It measured based on JISK7194.

Specifically, a test piece having a size of 20 mm × 40 mm is left still for 24 hours in an environment of 23° C. and 50% RH (relative humidity), and then the surface of the layer to be measured of the test piece is exposed, and a low resistivity meter (The Mitsubishi Chemical Analytech make, product name "Loresta GP MCP-T610 type") was used, and the surface resistivity and volume resistivity were measured.

The above measurement was performed 3 times for the surface resistivity, and the above measurement was performed 5 times for the volume resistivity, and Tables 1 and 2 show the average value of the measured values obtained in each measurement.

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 two release sheets is used as a test piece, and one release sheet of the test piece is used as a test piece. was removed and these values were measured about the surface of the exposed adhesive conductive layer (X).

In the measurement of the surface resistivity and volume resistivity of the non-tacky conductive layer alone, a substrate having a non-tacky conductive layer was used as a test piece, and the surface of the non-tacky conductive layer of the test piece was measured.

In addition, for the measurement of the surface resistivity of the conductive adhesive sheet, the conductive adhesive sheet prepared in Examples and Comparative Examples, in which the substrate, the non-stick conductive layer, the adhesive conductive layer (X) and the release sheet were laminated in this order, was used as a test piece. Only the value of the surface resistivity was measured with respect to the surface of the adhesive conductive layer (X) which used and the said peeling sheet of the said test piece was removed and exposed.

Preparation Example 1

(Preparation of base material having non-tacky conductive layer (Y-1))

A solution of polythiophene (Soken Chemicals) on a 50 µm thick polyethylene terephthalate (PET) film (manufactured by Toray Corporation, trade name “Lumirer”, surface resistivity: 1.18×10 ¹⁸ Ω/□) used as a substrate Co., Ltd. make, trade name "Verazole IW-103") is coated so that the thickness after drying becomes 2.4 µm to form a coating film, and the coating film is dried to form a non-adhesive conductive layer containing polythiophene (Y- A substrate having 1) was obtained.

Preparation 2

(Preparation of base material having non-tacky conductive layer (Y-2))

Poly(3,4-ethylenedioxythiophene)-poly( A solution containing 10 parts by mass (solid content) and 10 parts by mass of ethylene glycol of a dispersion of styrenesulfonic acid (PEDOT-PSS) (manufactured by Agfa, trade name "Orgacon S305") was prepared.

Then, on the same PET film as used in Production Example 1, the solution was applied so that the thickness after drying became 1.0 μm to form a coating film, and the coating film was dried to form a non-stick conductive layer containing PEDOT-PSS (Y- 2) was obtained.

Preparation 3

(Preparation of base material having non-tacky conductive layer (Y-3))

10 mass of multi-walled carbon nanotubes (CNT) (manufactured by Nanosil, trade name "NC7000", details as described later) per 100 parts by mass (solid content) of styrene-based resin (Krayton, trade name "1726M", SEBS) Part (solid content) was added, and the mixture was kneaded using a heat-kneader (manufactured by Toyo Seiki Seisakusho Co., Ltd., product name "30C150") under conditions of 100°C and 50 rpm to obtain a composite.

Then, the composite was sandwiched between the same PET film as used in Production Example 1 and a release sheet having a thickness of 75 µm (manufactured by Lintec Co., Ltd., trade name "SP-PET751031"), and a hot press machine (Tester Sangyo Co., Ltd.) Using the Shiki Corporation make, product name "SA-302"), it hot-pressed for 10 minutes under the conditions of 130 degreeC and 10 MPa. After hot pressing, the release sheet was removed to obtain a substrate having a non-stick conductive layer (Y-3) containing SEBS and CNT (10 parts by mass) having a thickness of 100.0 µm.

In this Example and the comparative example, in addition to the base material which has the non-tacky conductive layer produced by the manufacture examples 1-3 mentioned above, the base material which has the following non-tacky conductive layers was also used.

- "Substrate having a non-tacky conductive layer (YA) containing ITO": trade name "ITO-polyethylene terephthalate" (manufactured by Oike Kogyo Co., Ltd.). A 1.6 μm thick ITO film was deposited on one side of a 50 μm thick PET film (surface resistivity: 1.18×10 ¹⁸ Ω/□).

- "Substrate having a non-tacky conductive layer (YB) containing copper": trade name "Nikaflex" (manufactured by Nikan Kogyo Co., Ltd.). A copper film with a thickness of 35.0 μm was bonded with an adhesive on one side of a PET film with a thickness of 50 μm (surface resistivity: 1.18×10 ¹⁸ Ω/□).

- Substrate having a non-adhesive conductive layer (YC) containing aluminum: trade name "Metalumi #50" (manufactured by Toray Film Chemicals Co., Ltd.). An aluminum film having a thickness of 10.0 µm was deposited on one side of a 50 µm thick PET film (surface resistivity: 1.18×10 ¹⁸ Ω/□).

Table 1 shows various physical properties of the non-tacky conductive layer of the base material having the non-tacky conductive layer used in the present Example and the comparative example.

Examples 1 to 15, Comparative Examples 1 to 8

(1) Formation of the adhesive conductive layer (X)

Carbon-based filler (x2) of the type and blending amount shown in Table 2 (solid content relative to 100 parts by mass (solid content) of the adhesive resin) was added to ethyl acetate, and vibration by ultrasonic waves (42 kHz, 125 W) was performed with an ultrasonic cleaner. After 1 hour, a dispersion liquid of the carbon-based filler (x2) having a solid content concentration of 0.5% by mass was prepared in advance.

Then, to 100 parts by mass (solid content) of the adhesive resin (x1) of the type shown in Table 2, the dispersion of the carbon-based filler (x2) is added, and the type and compounding amount (solid content) shown in Table 2 are crosslinking agents and adhesion An imparting agent was further added as needed. Then, it diluted suitably with ethyl acetate, and it stirred until it became uniform, and the solution of the adhesive composition was prepared.

Then, the solution of the pressure-sensitive adhesive composition prepared as described above was applied to the release sheet (manufactured by Lintec Co., Ltd., trade name "SP-PET381031", thickness: 38 µm, polyethylene terephthalate film with a surface treated with silicone release treatment) on the release-treated surface It was apply|coated on top, the coating film was formed, it was made to dry, and the application layer was formed.

Next, a release sheet of the same kind as described above is separately laminated on the coating layer, and left still for 14 hours in an environment of 23° C. and 50% RH (relative humidity), then the coating layer is sufficiently crosslinked to have a thickness shown in Table 2 Only the adhesive conductive layer (X) of the obtained laminated body pinched|interposed by the peeling sheet of 2 sheets.

(2) Preparation of conductive adhesive sheet

In Examples 1 to 15 and Comparative Examples 7 to 8, the adhesive conductive layer (X) exposed by removing one release sheet of the laminate, and the non-adhesive property of a substrate having a non-stick conductive layer of the type shown in Table 2 The conductive layers were bonded together, and the conductive adhesive sheet was produced.

In Comparative Examples 1 to 6, the adhesive conductive layer (X) exposed by removing the release sheet on one side of the laminate, and a PET film having a thickness of 50 µm (manufactured by Toray Corporation, trade name “Lumiror”) were bonded. , a conductive adhesive sheet was produced.

Example 16

(1) Formation of the adhesive conductive layer (X)

Multi-walled carbon nanotube (CNT) (manufactured by Nanosil Co., Ltd., trade name "NC7000") per 100 parts by mass (solid content) of a styrene-based resin (manufactured by Toyo Adore Corporation, trade name "P-907Y", details as described later) ', details are as described later) in the blending amount (solid content) shown in Table 2, and using a heat kneader (manufactured by Toyo Seiki Seisakusho Co., Ltd., product name "30C150"), 100 ° C., It kneaded under the conditions of 50 rpm, and obtained the composite.

Then, the composite was sandwiched between two release sheets (manufactured by Lintec Corporation, trade name "SP-PET751031", thickness: 75 µm), and a hot press machine (manufactured by Tester Sangyo Corporation, product name "SA") -302'), it was heat-pressed for 10 minutes under 130 degreeC and 10 Mpa conditions, and only the adhesive conductive layer (X) obtained the laminated body pinched by the peeling sheet of 2 sheets.

(2) Preparation of conductive adhesive sheet

The adhesive conductive layer (X) containing a styrenic resin, which was exposed by removing one release sheet of the laminate, and the non-stick conductive layer of the base material having the non-stick conductive layer (Y-2) are bonded to each other, and the conductive adhesive sheet was made.

Details of each component among the adhesive compositions used in Examples and Comparative Examples shown in Table 2 are as follows.

(Adhesive resin (x1))

・“Acrylic resin”: methyl acetate solution of an acrylic polymer containing n-butyl acrylate (BA) and acrylic acid (AA), BA/AA=90.0/10.0 (parts by mass), Mw: 700,000, solid content concentration: 33.6 mass%.

-"Urethane resin": Lion Specialty Chemicals, Ltd. make, brand name "US-902A", urethane resin, Mw=56,000.

・“PIB-based resin”: 90.9 parts by mass (solid content) of Mw 34 only PIB-based resin (manufactured by BASF, trade name “Opanol B50”) and PIB-based resin with Mw 200,000 (manufactured by BASF, trade name “Opanol B30”) ) mixed resin with 9.1 parts by mass (solid content).

- "Styrenic resin": Toyo Adore Co., Ltd. make, brand name "P-907Y", mixed resin containing SEBS and SEB, total content of SEBS and SEB = 30 mass %, softening point = 112 degreeC.

(Carbon-based filler (x2))

"NC7000": brand name, manufactured by Nano Real Co., Ltd., cylindrical multi-walled carbon nanotube, average aspect ratio (H/L): 150, long side length (H): 1.5 µm, short side length (L): 10 nm.

・“AMC”: brand name, manufactured by Ube Kosan Co., 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)

- "Colonate L": A brand name, the Tosoh Corporation make, isocyanate type crosslinking agent, solid content concentration: 75 mass %.

(tackifier)

・“Alcon P-125”: trade name, manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point: 125°C.

・“YS Polystar K125”: trade name, manufactured by Yasuhara Chemical Co., Ltd., terpene phenol-based resin, softening point: 125°C.

(Other Ingredients)

- A mixture of other components (tackifier, plasticizer, etc.) other than the component (x1) contained in "P-907Y" used as a styrene resin.

Table 2 shows the various physical property values measured based on the said method about the electroconductive adhesive sheet produced as mentioned above.

From Table 2, it can be seen that the conductive adhesive sheets of Examples 1 to 16 have good adhesive strength, and have a low surface resistivity and are excellent in antistatic properties and conductivity compared to the conductive adhesive sheets of Comparative Examples 1 to 8 .

Since the electroconductive adhesive sheet of this invention has favorable adhesive force and has a low surface resistivity, it is excellent in antistatic property and electroconductivity.

Therefore, the conductive adhesive sheet of the present invention prevents ignition by sparks generated from static electricity such as electromagnetic shielding materials for containers housing electronic devices such as computers and communication devices, ground wires of electrical parts, and the like, and furthermore, static electricity such as triboelectrics. It is suitable as a joining member used for members, such as ashes.

1A, 1B, 2A, 2B, 3, 4: Conductive adhesive sheet
11: adhesive conductive layer (X)
11a: first adhesive conductive layer (XI)
11b: second adhesive conductive layer (X-II)
12: Non-stick conductive layer (Y)
12a: first non-tacky conductive layer (YI)
12b: second non-tacky conductive layer (Y-II)
13: description
14: release sheet
21: two-layer body
21a: first two-layer body
21b: second two-layer body
22: three-layer body

Claims (14)

It is an electrically conductive adhesive sheet which has at least an adhesive conductive layer (X) and a non-stick conductive layer (Y),
The adhesive conductive layer (X) is a layer formed of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin (x1) and a carbon-based filler (x2) having an average aspect ratio of 1.5 or more,
Content of the carbon-based filler (x2) contained in the said adhesive composition is 0.01-15 mass parts with respect to 100 mass parts of adhesive resin (x1),
The conductive pressure-sensitive adhesive sheet in which the non-adhesive conductive layer (Y) is a layer containing at least one conductive material selected from the group consisting of conductive polymers, carbon-based fillers, and metal oxides. The conductive adhesive sheet according to claim 1, wherein the surface resistivity (ρ _SX ) of the adhesive conductive layer (X) alone is 1.0×10 ² to 1.0×10 ¹⁰ Ω/□. The conductive adhesive sheet according to claim 1, wherein the surface resistivity (ρ _SY ) of the non-tacky conductive layer (Y) alone is 1.0×10 ⁻² to 1.0×10 ⁸ Ω/□. The conductive adhesive sheet according to claim 1, wherein the carbon-based filler (x2) contained in the pressure-sensitive adhesive composition is a carbon nanomaterial. The conductive layer according to claim 1, wherein the non-stick conductive layer (Y) is a layer containing at least one conductive material selected from the group consisting of polythiophene, PEDOT-PSS, carbon nanomaterials and ITO (indium tin oxide). adhesive sheet. The conductive adhesive sheet according to claim 1, wherein the conductive material contained in the non-stick conductive layer (Y) has a density of 0.8 to 2.5 g/cm 3 . According to claim 1, wherein the pressure-sensitive adhesive resin (x1) contained in the pressure-sensitive adhesive composition is one selected from the group consisting of acrylic resins, urethane-based resins, polyisobutylene-based resins, styrene-based resins, polyester-based resins and polyolefin-based resins An electroconductive adhesive sheet containing the above adhesive resin. The conductive adhesive sheet according to claim 1, wherein the adhesive conductive layer (X) has a thickness (t _X ) of 1 to 1200 μm. The conductive pressure-sensitive adhesive sheet according to claim 1, wherein the non-stick conductive layer (Y) has a thickness (t _Y ) of 0.01 to 200 μm. The conductive adhesive sheet according to any one of claims 1 to 9, which has a structure in which a base material, a non-stick conductive layer (Y), and an adhesive conductive layer (X) are laminated in this order. The conductive pressure-sensitive adhesive sheet according to claim 10, which has a two-layer body composed of a non-stick conductive layer (Y) and an adhesive conductive layer (X) on both surfaces of the substrate, respectively. The conductive adhesive sheet according to claim 10, wherein the substrate is an insulating substrate having a surface resistivity of 1.0×10 ¹⁴ Ω/□ or more. The conductive adhesive sheet according to any one of claims 1 to 9, wherein the two-layer body composed of the adhesive conductive layer (X) and the non-stick conductive layer (Y) is sandwiched by two release sheets. . The three-layer body according to any one of claims 1 to 9, wherein a first adhesive conductive layer (X-I), a non-stick conductive layer (Y), and a second adhesive conductive layer (X-II) are laminated in this order. An electroconductive adhesive sheet having a structure sandwiched by two release sheets.

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