JP7172288B2 - Conductive hot-melt adhesive composition and laminate - Google Patents

Description

The present invention provides a hot-melt adhesive composition that can easily and firmly bond electrically conductive adherends, such as porous members such as silver materials, stainless steel materials, and water-containing wood materials, while maintaining continuity between them. about things.

BACKGROUND ART In recent years, with the rapid progress of information technology, the development of devices capable of obtaining information more accurately over a long period of time with less power consumption is being vigorously pursued both in Japan and overseas. In particular, the breakthrough in sensor technology has been tremendous. By installing sensors everywhere, it is now possible to semi-permanently acquire information that was difficult to handle in the past or that had to rely on on-site skill. Improving fixing technology makes it possible to obtain information easily.
Against this background, there is a growing demand for a conductive adhesive composition that can easily and firmly bond conductive materials while maintaining electrical continuity between them. Modularization of electronic materials is progressing in technological progress in the field of electronics, and conductive adhesives are essential in such fields.
In addition, by strongly adhering such a conductive adhesive composition to clothing, it can be utilized as a biosensor. However, the current situation is that there is no hot-melt adhesive composition on the market that is compatible with both high conductivity and adhesive strength and allows simple adhesion.

Japanese Patent Application Laid-Open No. 2001-200225 JP-A-2002-155261

An object of the present invention is to provide a conductive hot-melt adhesive that can easily and firmly bond adherends together while exhibiting high conductivity.

The inventors of the present invention have made intensive studies to solve the above problems, and as a result, have found that simple and strong adhesion can be achieved with the following hot-melt adhesive composition, and have completed the present invention.

That is, the present invention provides a conductive hot-melt adhesive composition containing a thermoplastic resin and a conductive filler, wherein the volume resistivity is less than 1×10 ³ Ωcm. of less than 5 MPa at 25°C.

Further, in the present invention, the conductive filler is at least selected from the group consisting of graphite, carbon black, carbon nanotubes, graphene, graphene oxide, silver, copper, tin, zinc, zinc oxide, nickel, manganese, and ITO. The conductive hot-melt adhesive composition is characterized in that it is one type.

Further, in the present invention, the conductive hot melt adhesive is characterized in that the conductive filler is at least one selected from the group consisting of graphite, carbon black, carbon nanotubes, graphene, and graphene oxide. Regarding the composition.

The present invention also relates to the conductive hot-melt adhesive composition, characterized in that the content of the conductive filler is 2% by weight or more and 65% by weight or less with respect to the entire composition.

Further, in the present invention, the thermoplastic resin is a styrene-based thermoplastic resin, a polyamide-based thermoplastic resin, a polyolefin-based thermoplastic resin, a polyester-based thermoplastic resin, a polyvinyl chloride-based thermoplastic resin (PVC), ethylene-vinyl acetate. The present invention relates to the conductive hot-melt adhesive composition characterized by containing at least one selected from the group consisting of thermoplastic resins (EVA) and ethylene-propylene-diene-based thermoplastic resins (EPDM).

Further, in the present invention, the styrene-based thermoplastic resin is a styrene-isoprene-styrene block copolymer (SIS), a hydrogenated styrene-ethylene- propylene -styrene block copolymer (SEPS), a styrene-butylene-styrene Block copolymer (SBS), hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-isoprene-styrene block copolymer (SBIS), or styrene- ethylene-ethylene-propylene - The above conductive hot melt adhesive composition, which is a hydrogenated styrene block copolymer (SEEPS).

The present invention also relates to the conductive hot-melt adhesive composition, further comprising a tackifier.

The present invention also relates to the above hot-melt adhesive composition, which further comprises a softening agent.

The present invention also relates to a laminate comprising a substrate, the conductive hot-melt adhesive composition, and an adherend, which are laminated in this order.

The present invention also relates to the above laminate, wherein the substrate is a conductor.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a conductive hot-melt adhesive composition that exhibits high conductivity and adhesive strength.

FIG. 1 shows a configuration example of the laminate of the present invention.

Embodiments of the present invention will be described below.

The conductive hot-melt adhesive composition of the present invention is characterized by containing a thermoplastic resin and a conductive filler.

<Conductive filler>
Examples of conductive fillers used in the present invention include metals such as silver, gold, copper, nickel, zinc, zinc oxide, manganese, and aluminum, tin oxide-doped indium oxide (ITO), tin oxide-doped indium oxide (FTO), tin oxide (IO ), metal oxides such as neodymium, barium, and indium oxides, organic materials such as polythiophenes, polypyrroles, polyanilines, and oligothiophenes, inorganic insulators such as alumina and glass, and surfaces of polymers such as polyethylene and polystyrene. coated with a conductive substance, and carbon-based materials such as carbon black, graphite, graphene, carbon nanotube, fullerene, graphene oxide, and acetylene black, but are not limited to these. These may be used alone or in combination of two or more. It should be noted that the conductive filler is preferably silver- or carbon-based.

The shape of the conductive filler may be flaky (scale-like), spherical, needle-like, fibrous, or dendritic, but is not limited to these. When it is desired to reduce the amount of the conductive filler to be added in order to strengthen the adhesive strength, flaky (scale-like) and mixtures of flaky (scale-like) and other conductive fillers are preferred. Above all, it is preferable to use a spherical or spike-shaped conductive filler as another mixture because it is possible to express low resistivity with a small addition and because it becomes easy to exhibit electrical conductivity in the thickness direction. Among them, it is preferable to use Ketjenblack.

The content ratio of the conductive filler with respect to the entire conductive hot melt adhesive composition is not particularly limited, but from the viewpoint of adhesive strength and conductivity, it is 40 to 80% by weight for metals such as silver and gold. is preferred, and 50 to 70% by weight is more preferred. If it is less than 40% by weight, the electrical conductivity will be insufficient, and if it exceeds 80% by weight, the adhesive strength will be insufficient. On the other hand, carbon-based materials such as carbon black and graphite preferably contain 2 to 65% by weight, more preferably 5 to 40% by weight. If it is less than 2% by weight, the electrical conductivity will be insufficient, and if it exceeds 60% by weight, the adhesive strength will be insufficient.

<Hot melt adhesive>
The hot-melt adhesive composition of the present invention is prepared by mixing a thermoplastic resin, a softening agent, a tackifier, an antioxidant, and other optional ingredients into a melting pot equipped with rolls, a Banbury mixer, a kneader, and an agitator. Alternatively, it can be obtained by using a hot-melt adhesive obtained by heat-mixing using a uniaxial or twin-screw extruder or the like, or a solvent-based adhesive obtained by dissolving in an appropriate solvent and stirring and mixing. The hot-melt adhesive composition used in the present invention is preferably a hot-melt adhesive that does not use a solvent from the viewpoint of complicating the process due to removal of the solvent and the accompanying cost increase, and from the viewpoint of the adverse effect on the global environment due to the use of the solvent. . The hot-melt adhesive composition used in the present invention can be used with a thermoplastic resin alone, but it is better to include a softener, a tackifier, and an antioxidant from the viewpoint of imparting fluidity, adhesiveness, and oxidation stability. preferable.

<Thermoplastic resin>
The thermoplastic resin may be a so-called hot-melt resin, which is a non-curing resin that becomes flowable at elevated temperatures and returns to a non-flowable state upon cooling. It can also be a curable resin that undergoes a curing (crosslinking) reaction after the thermoplastic resin has been applied to the substrate.

Thermoplastic resins include polyurethane, acrylonitrile, diene, acrylic, butadiene, polyamide, polyvinyl butyral, olefin, isoprene, butadiene, chloroprene, acrylonitrile, polyester, polyvinyl chloride, It may contain one or more selected from the group consisting of thermoplastic resins including styrene, ethylene-vinyl acetate, fluorine, silicone and copolymers thereof. However, it is not limited to these resins. From the viewpoint of durability, weather resistance, heat resistance and adhesive strength, the thermoplastic resin may more preferably contain a styrene-based thermoplastic resin. The thermoplastic resin may be used singly or in combination of two or more. Furthermore, the thermoplastic resin may be a copolymer formed by linking different monomers.

More specifically, styrenic elastomers generally have polystyrene blocks and rubber intermediate blocks, and the polystyrene portions form physical crosslinks (domains) to serve as bridge points, which serve as intermediate blocks. The rubber block gives the product rubber elasticity. Intermediate soft segments include polybutadiene (B), polyisoprene (I) and polyolefin elastomers (ethylene/propylene, EP). and radial (radical type). Among the preferred styrene elastomers mentioned above, in the present invention, more specifically, styrene / isoprene / styrene block copolymer (SIS), hydrogenated styrene/ethylene/ propylene /styrene block copolymer (SEPS), styrene/ Butylene-styrene block copolymer (SBS), hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-isoprene-styrene block copolymer (SBIS) or styrene- ethylene-ethylene - One or more selected from the group consisting of hydrogenated products of propylene /styrene block copolymers (SEEPS) can be included. However, it is not limited to these resins.

<Tackifier>
Examples of tackifiers include hydrogenated terpene-based resins, terpene-based resins, hydrogenated rosin-based resins, rosin-based resins, hydrogenated hydrocarbon-based resins, hydrocarbon-based resins, epoxy-based resins, hydrogenated Epoxy resin, ketone resin, hydrogenated ketone resin, polyamide resin, hydrogenated polyamide resin, elastomer resin, hydrogenated elastomer resin, phenolic resin, hydrogenated phenolic resin Resins, petroleum-based resins, hydrogenated petroleum-based resins, styrenic resins, hydrogenated styrenic resins, and the like. These tackifying resins can be used alone or in combination of two or more.
Among these, hydrogenated hydrocarbon-based resins are preferable from the viewpoint of durability. Hydrogenation eliminates conjugated double bonds in the intramolecular structure, so hot melt adhesives containing tackifiers are less likely to deteriorate due to light or heat when permanently adhered to adherends. Adhesive strength can be maintained.

<Softener>
Softening agents include, for example, petrolatum, mineral oils, vegetable oils, animal oils and the like. Mineral oils include liquid paraffin, paraffin, paraffinic mineral oils in which the number of paraffin chain carbon atoms accounts for 50% or more of the total carbon number, naphthenic mineral oils in which the number of naphthene ring carbon atoms accounts for 30 to 40% by weight of the total carbon number, and aromatic mineral oils in which the number of aromatic carbon atoms accounts for 30% by weight or more of the total number of carbon atoms. Vegetable oils and fats: olive oil, carnauba wax, rice germ oil, corn oil, sasanqua oil, camellia oil, castor oil, jojoba seed oil, mink oil, eucalyptus leaf oil and the like. Animal oils and fats: beeswax, squalane, and honey can be mentioned. Others, mystylic acid, oleic acid, isopropyl mystylate, zinc mystylate, octyldodecyl myristate, glyceryl triisooctanoate, octyldodecanol, hexyldecanol, diisopropyl adipate, diethyl sebacate, stearic acid, isostearic acid, crotamiton, medium chain Fatty acid triglycerides, ethylene glycol salicylate, cetyl ethylhexanoate, glycol distearate, cetearyl alcohol, cetanol, cetyl palmitate, ethylhexyl palmitate, isopropyl palmitate, behenyl alcohol and the like can also be mentioned as softening agents. These softeners can be used alone or in combination of two or more.

<Antioxidant>
Examples of antioxidants include pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4- hydroxyphenyl)propionate, diethyl [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxy Ethylene)bis[3-(5-t-butyl-4-hydroxy-m-tolyl]propionate, tris(2,4-di-t-butylphenyl)phosphite, bis(2,4-di-t-butyl phenyl) pentaerythritol diphosphite, etc. The phenolic antioxidant is preferably pentaerythritol tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], and phosphorus antioxidant Preferably, the agent is tris(2,4-di-t-butylphenyl)phosphite.

<Other ingredients>
The hot-melt adhesive composition may contain various additives, as long as they do not impair the effects of the present invention. For example, curing agents such as polyisocyanates, epoxy resins, polycarbodiimide compounds, organic or Inorganic fillers can be incorporated. Such fillers may be composed of materials such as polymers, ceramics, metals, metal oxides, metal salts, and dyes and pigments. Moreover, the shape is not particularly limited, and may be, for example, particulate or fibrous. In addition, liquid rubber, silane coupling agent, titanate coupling agent, flame retardant, storage stabilizer, antioxidant, metal Deactivators, UV absorbers, thixotropy-imparting agents, leveling agents, anti-foaming agents, dispersion stabilizers, fluidity-imparting agents, anti-foaming agents, colorants and the like can also be added. Moreover, a solvent may be included in order to improve fluidity.

<Conductive Hot Melt Adhesive Composition>
The conductive hot-melt adhesive composition of the present invention comprises the above-mentioned hot-melt adhesive containing a thermoplastic resin as an essential component, a conductive filler as an essential component, and, if necessary, a softening agent, a tackifier, and an oxidizing agent. It can be produced by uniformly dispersing the inhibitor and other ingredients after blending.

Dispersion of the hot-melt adhesive composition and the conductive filler is performed by dispersing the hot-melt adhesive composition at a high temperature of 150° C. or higher using a kneader, Banbury mixer, single-screw extruder, twin-screw extruder, three-roll or two-roll. The hot-melt adhesive composition and the conductive filler are melted at a temperature of 150° C. or less as long as the hot-melt adhesive composition and the conductive filler can be melted and kneaded. You can knead it. Alternatively, after dissolving the hot melt adhesive composition in a solvent and adding a conductive filler, a planetary stirring method, a three-roll method, a two-roll method, a scandex method, a bead mill method, a jet mill method, a starburst method, It is carried out by the sand mill method. The solvent to be used is not particularly limited as long as it dissolves the thermoplastic resin and the hot-melt adhesive composition. However, a dispersing method other than the above may be used as long as the physical properties are not degraded.

<Laminate>
The conductive hot-melt adhesive composition of the present invention has a conductive hot-melt adhesive composition layer by coating or printing a conductive hot-melt adhesive composition on one side of a substrate, and is a sheet type. It can be used as an electrode.
The method of coating and printing the conductive hot-melt adhesive composition is not particularly limited. Coating methods include slot spray coating method, omega coating method, spiral coating method, control seam coating method, slot spray coating method, dot coating method, hot melt applicator coating method, hot melt coater coating method, blade coat coating method, and dip coating. Coating method, gravure coating method, curtain spray coating method, bead coating method, hot melt roll coater spin coat coating method, and printing methods include inkjet printing method, spray printing method, roll coating printing method, doctor roll printing method. , a doctor blade printing method, a curtain coat printing method, a slit coat printing method, a screen printing method, a reverse printing method, a push coat printing method, a slit coater printing method, and the like. There are no particular restrictions on the drying conditions when a solvent is used, and examples include hot air drying, infrared rays, and depressurization. As the drying conditions, although it depends on the film thickness and the selected organic solvent, hot air heating at about 60 to 200° C. is usually used. The thickness of the conductive hot-melt composition is preferably 100-300 μm. The conductive hot melt composition layer can also be crosslinked by heating or UV irradiation.

<Base material>
The substrate is selected from the group consisting of resin sheets, paper, and aluminum sheets (aluminum foil). For example, resin sheets include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate resins, polyarylate resins, acrylic resins, polyphenylene sulfide resins, polystyrene resins, and vinyl resins. , vinyl chloride resins, polyimide resins, epoxy resins, and polyolefin resins such as polyethylene, polypropylene, and polynorbornene. Moreover, a laminate obtained by laminating a metal on these sheets may be used, for example, a laminate obtained by laminating a metal on a polyethylene terephthalate (PET) sheet may be used. In addition, since the base material may be deformed by heat, a base material having high heat resistance such as a polyimide sheet, a polynaphthalene sheet, a propylene sheet, a silicone resin sheet, or a base material having improved heat resistance due to filler filling is preferable.

<Adhesion process>
Next, the conductive hot melt adhesive composition and the substrate are placed on the adherend, and the conductive hot melt composition is melted on the adherend using an iron, an IH heating device, or the like, although not particularly limited. It can be produced by bonding a conductive hot-melt adhesive composition and an adherend. A plurality of substrates such as conductors and non-conductors can be used as the substrate, but there is no particular limitation. Examples of adherends include silver, stainless steel, copper, iron, aluminum, concrete, mortar, slate, wood, ceramics, glass, cork, paper, minerals, non-ferrous metals, polymers, human skin, etc., but are particularly limited. never.

<Other laminates>
As another component of the laminate, a mesh layer may be provided between the composition and the base material in order to improve the strength of the laminate.

<Resistivity>
It is preferable to set the volume resistivity to a value of less than 1×10 ³ Ω·cm when forming the conductive hot-melt adhesive composition. The reason for this is that if the volume resistivity of the conductive hot-melt adhesive composition falls within this range, the conductive hot-melt adhesive sheet can be provided with suitable conductivity. Therefore, the volume resistivity of the conductive hot-melt adhesive composition is more preferably less than 1×10 ³ Ω·cm, more preferably less than 1×10 ¹ Ω·cm. A detailed method for measuring the volume resistivity will be specifically described in Examples.

<Elastic modulus>
A preferred range for the modulus of elasticity of the compositions of the invention is less than 5 MPa, more preferably less than 1 MPa. The reason for this is that, if the elastic modulus of the conductive hot-melt adhesive composition is a value within such a range, the conductive hot-melt adhesive sheet can follow complicated shapes of adherends, and further has a suitable adhesive strength. This is because it can be expressed. A detailed method for measuring the elastic modulus will be specifically described in Examples.

<Adhesive strength>
The adhesive strength value of the conductive hot-melt adhesive composition varies depending on the adherend, but is preferably 2 N/25 mm or more and less than 10 N/25 mm, more preferably 10 N/25 mm or more. A detailed method for measuring adhesive strength will be specifically described in Examples.

EXAMPLES Hereinafter, the present invention will be described specifically and in detail with reference to examples, but these examples are merely one aspect of the present invention, and the present invention is not limited by these examples. In the table, "part" means "part by weight" and "%" means "% by weight".

[Adjustment of hot melt adhesive]
(Production Examples 1 to 29)
In a stainless steel beaker equipped with a stirrer, 1:10 parts of a softener as a softener, 1:40 parts of SIS as a thermoplastic resin, 1:50 parts of a tackifier as a tackifier, and 1:1 part of an antioxidant are added. It was put in and melted by heating to a temperature range of 150°C. After that, stirring was performed to obtain a uniform molten solution, and then the hot melt adhesive 1 was obtained by cooling.
Hot melt adhesives 2 to 29 were prepared in the same manner as the hot melt adhesive 1, except that the raw materials and composition ratios were changed as shown in Table 1.

[Adjustment of conductive filler]
(Production Examples 30-50)
In the number of parts shown in Table 2, each filler powder was mixed by hand to obtain conductive fillers 1 to 21.

[Adjustment of conductive hot melt adhesive]
1:70 parts of the hot melt adhesive and 1:30 of the conductive filler were kneaded in a kneader equipped with a stirrer at 150° C. for 3 hours to obtain a conductive hot melt adhesive composition 1.
Conductive hot melt adhesive 2 was prepared in the same manner as conductive hot melt adhesive 1, except that the types and blending ratios of the hot melt adhesive and the conductive filler were changed as shown in Table 3. ~65 was adjusted.

The abbreviations of the thermoplastic resin, tackifier, softener and other components listed in Table 1 are shown below.

<Thermoplastic resin>
・SEBS1: Kraton Co., Ltd. Product name: G1652
・ SEBS2: Kraton Co., Ltd. Product name: G1726
・SEBS3: Kraton Co., Ltd. Product name: G1650
・ SEBS4: Kraton Co., Ltd. Product name: G1651
・SBS1: Kraton Co., Ltd. Product name: D0243
・SBS2: Kraton Co., Ltd. Product name: D4433
・SIS1: Kraton Co., Ltd. Product name: D1117
・SIS2: Kraton Co., Ltd. Product name: D1114
・SEPS1: Kuraray Co., Ltd. Product name: SEPTON 2063
・SEPS2: Kuraray Co., Ltd. Product name: SEPTON 2005
・SEPS3: Kuraray Co., Ltd. Product name: G1730
・Olefin 1: Ube Maruzen Polyethylene Co., Ltd. Product name: UBE BOND F1100
・Olefin 2: Toyobo Co., Ltd. Product name: PMA H3000P
・Polyamide 1: Henkel Co., Ltd. Product name: PA6858
・Polyamide 2: Arkema Co., Ltd. Product name: Platamide M1276
・Polyester 1: Toyobo Co., Ltd. Product name: Byron 200
・PVC1: Mitsubishi Chemical Corporation Product name: Sunplane FG40EA
・EVA1: DuPont Mitsui Polychemicals Co., Ltd. Product name: EVAFLEX V5733
・EPDM1: JSR Corporation Product name: EP96

<Tackifier>
・ Tackifier 1: Arakawa Chemical Industries, Ltd. Product name: P-100
・ Tackifier 2: Harima Kasei Co., Ltd. Product name: Haritak F
・ Tackifier 3: Yasuhara Chemical Co., Ltd. Product name: YS Polyster T30
・ Tackifier 4: Arakawa Chemical Industries, Ltd. Product name: P-90

<Softener>
・ Softener 1: Idemitsu Kosan Co., Ltd. Product name: Diana Process Oil NS90S
・ Softener 2: Idemitsu Kosan Co., Ltd. Product name: Diana Process Oil PW90
・ Softener 3: Japan Sun Oil Co., Ltd. Product name: SUNPURE N100

<Other ingredients>
・Antioxidant 1: BASF Japan Ltd. Product name: Irganox 1010
・ Liquid rubber 1: Kuraray Co., Ltd. Product name: Kuraprene LIR290

The abbreviations of the conductive fillers listed in Table 2 are shown below.
・Filler 1: SEC Carbon Co., Ltd. Product name: SGO-10 (flaky graphite)
・Filler 2: CABOT Co., Ltd. Product name: VULCAN XC-72R (carbon black)
・ Filler 3: Lion Specialty Chemicals Co., Ltd. Product name: EC300J (Ketjen Black)
・ Filler 4: Lion Specialty Chemicals Co., Ltd. Product name: EC200L (Ketjen Black)
・ Filler 5: Lion Specialty Chemicals Co., Ltd. Product name: EC600JD (Ketjen Black)
・Filler 6: Nippon Graphite Industry Co., Ltd. Product name: CMX-100 (graphite)
・Filler 7: Nippon Graphite Industry Co., Ltd. Product name: LEP (graphite)
・Filler 8: Hyperion Catalysis International Co., Ltd. Product name: Hyperion BN (carbon nanotube)
・ Filler 9: i-Tech Co., Ltd. Product name: iGurafen-α (graphene)
・Filler 10: Fukuda Metal Foil & Powder Co., Ltd. Product name: Ag-XF301S (silver)
・Filler 11: Taimei Chemical Industry Co., Ltd. Product name: Taimicron TM-DA (alumina)

Next, the following tests were carried out using the obtained compositions. (Examples 1 to 65, Comparative Examples 1 to 5)

1. Measurement of Volume Resistivity Sheets composed of laminates of compositions and plastic films obtained in Composition Examples 1 to 65 and Comparative Examples 1 to 5 by applying pressure with a press plate while the composition is being heated. is formed, and the laminate is cut to 1.5 cm by 3 cm, and a low resistance resistivity meter (manufactured by Mitsubishi Chemical Analytech Co., Ltd.: Lorestar GX MCP-T700) is used. Volume resistivity was measured. Evaluation was performed in two stages.
In the case of "○" evaluation, this claim is satisfied.
○: volume resistivity less than 1×10 ³ Ωcm ×: volume resistivity 1×10 ³ Ωcm or more

2. Measurement of elastic modulus The tensile test of the conductive hot-melt adhesive was performed using a tensile tester EX-SX manufactured by Shimadzu Corporation. As a measurement method, the compositions obtained in Composition Examples 1 to 65 and Comparative Examples 1 to 5 were cut into 5 mm × 1 mm × 24 mm as measurement samples, and after placing the measurement samples at 25 ° C., A crosshead speed of 50 mm/min. Then, the crosshead displacement and the load history up to immediately after fracture were measured, and the strain in the longitudinal direction of the measurement sample was measured using a strain gauge. The elastic modulus was calculated from the obtained stress-strain diagram.
◎: Elastic modulus is less than 1 MPa ○: Elastic modulus is 1 MPa or more and less than 5 MPa ×: Elastic modulus is 5 MPa or more

3. Measurement of adhesive strength The adhesive strength of the conductive hot-melt adhesive was measured using a tensile tester EX-SX manufactured by Shimadzu Corporation. Measurement samples were prepared by applying conductive hot-melt adhesive compositions 1 to 65 and sheets composed of a laminate of a composition having a thickness of 200 μm and a polyimide film obtained in Comparative Examples 1 to 5 to various covers of 7 cm × 7 cm. It is attached to an adherend (preliminarily surface treated with a grinder in the case of concrete), and a press plate with a size of 2 cm × 7 cm is heated to 200 ° C. and a pressure of 0.1 MPa is applied for 1 minute. It was performed by pressing and bonding. After the heating was finished, the sample was left for 24 hours until the temperature returned to room temperature, which was used as a measurement sample. For the measurement method, a measurement sample in which the composition sheet was adhered to an adherend was adjusted to have a width of 25 mm, and the edge of the sheet was held at an angle of 90 degrees at a speed of 50 mm/min. The adhesive strength was calculated from the load when the film was peeled off with , and was evaluated in three stages according to the following.
◎: Adhesive strength is 10N or more ○: Adhesive strength is 2N or more and less than 10N ×: Adhesive strength is less than 2N Grinder used: Monotaro Slim Disc Grinder (MRO-100DG)
Heat press used: TP-701B

From the results in Table 3, the laminates formed using the compositions prepared in Examples 1 to 65 were obtained using the conductive hot melt adhesive compositions prepared in Comparative Examples 1 to 5. It was found to have very good adhesiveness and volume resistivity as compared with the formed laminate of the comparative example. That is, it was found that the compositions prepared in Examples 1 to 65 can be suitably used for forming a conductive hot melt adhesive laminate compared to the compositions prepared in Comparative Examples 1 to 5. .

Claims (6)

A conductive hot-melt adhesive composition containing a thermoplastic resin and a conductive filler, wherein the volume resistivity is less than 1×10 ³ Ωcm, and the elastic modulus of the conductive hot-melt adhesive composition is 25°C. is less than 5 MPa at
In addition, it contains a softening agent,
The thermoplastic resin is a styrene-based thermoplastic resin, a polyamide-based thermoplastic resin, a polyolefin-based thermoplastic resin, a polyester-based thermoplastic resin, a polyvinyl chloride-based thermoplastic resin (PVC), an ethylene-vinyl acetate-based thermoplastic resin ( EVA), and at least one selected from the group consisting of ethylene-propylene-diene-based thermoplastic resins (EPDM) ,
A conductive hot-melt adhesive composition, wherein the conductive filler is at least one selected from the group consisting of graphite, carbon black, carbon nanotubes, graphene, and graphene oxide . 2. The conductive hot-melt adhesive composition according to claim 1, wherein the conductive filler content is 2% by weight or more and 65% by weight or less with respect to the entire composition. Styrene-based thermoplastic resins include styrene-isoprene-styrene block copolymer (SIS), hydrogenated styrene-ethylene-propylene-styrene block copolymer (SEPS), and styrene-butylene-styrene block copolymer (SBS). ), hydrogenated styrene/ethylene/butylene/styrene block copolymer (SEBS), styrene/butadiene/isoprene/styrene block copolymer (SBIS), or styrene/ethylene/ethylene/propylene/styrene block copolymer The conductive hot melt adhesive composition according to claim 1 or 2, which is a hydrogenated product (SEEPS) of The electrically conductive hot melt adhesive composition according to any one of claims 1 to 3 , further comprising a tackifier. A laminate comprising a substrate, the conductive hot-melt adhesive composition according to any one of claims 1 to 4 , and an adherend, which are laminated in this order. 6. The laminate according to claim 5 , wherein the substrate is a conductor.

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