JPH11302615A - Conductive adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a conductive adhesive tape which can exhibit excellent humidity resistance and can develop stable electrical connection even when it is applied to an adherend having irregularities such as bends and steps. SOLUTION: There is provided a conductive adhesive tape T1 consisting of a conductive adhesive tape body (A) consisting of a conductive support 1 and a pressure-sensitive adhesive layer 2 formed on either surface of the support, wherein electrical connection exists between the sticking surfaces of the support 1 and the layer 2, and an auxiliary tape (B) consisting of a support 4 and an adhesive layer 5 formed on either surface of the support 4 and being larger in width than body A, wherein the surface on the side of the support of the body A and the surface on the side of the adhesive layer of tape B are stuck to each other so as to leave spaces in the direction of the width of tape B, and wherein the support of the tape B is made of a plastic film having a tensile modulus of 60 kgf/mm<2> or below and a stress relaxation at 10% elongation of 40% or above. The material for making the support 4 of tape B is exemplified by a flexible vinyl chloride resin or an ionomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive adhesive tape which is useful for electrically connecting two separate places such as grounding a printed wiring board.

[0002]

2. Description of the Related Art The installation of a printed wiring board, the grounding of an outer shield case of an electronic device, the grounding of a TV cathode ray tube, etc.
When electrically conducting between the two separated locations, a pressure-sensitive adhesive type conductive adhesive tape is attached over the required two locations, and the conductive surface of the conductive adhesive tape is adhered to the surface to be adhered. Electrical conduction between the two places is performed by electrical conduction with a material and longitudinal electrical conduction of the conductive base material.

Conventionally, as such a conductive tape, a conductive tape in which a pressure-sensitive adhesive layer containing a conductive filler is laminated on one side of a metal foil substrate has been used.
Further, Japanese Utility Model Publication No. 63-46980 discloses a conductive base material and a pressure-sensitive adhesive layer provided on at least one surface of the conductive base material. There is disclosed a conductive adhesive tape provided with a conductive portion at a desired interval and having a terminal portion penetrating the adhesive layer and having a terminal portion slightly covering the adhesive layer surface at the end thereof.

Japanese Patent Application Laid-Open No. 8-185714 discloses an improved conductive adhesive tape described in the above-mentioned Japanese Utility Model Publication No. 63-46980. There has been proposed an adhesive tape comprising a pressure-sensitive adhesive layer provided on one surface of the tape base material and pasting an auxiliary tape wider than the conductive adhesive tape. According to such an adhesive tape, it is possible to prevent moisture and moisture from entering the contact interface between the pressure-sensitive adhesive layer and the surface to be adhered, and to suppress a decrease in conductive performance.

[0005] In addition, in order to prevent a hand cut by a metal foil, a conductive tape in which a pressure-sensitive adhesive layer containing a conductive filler is laminated on one side of the metal foil substrate is also used. Adhesive tapes having an auxiliary tape made of a polyester substrate adhered to the surface are commercially available.

When such a conductive adhesive tape with an auxiliary tape is stuck to a completely smooth adherend, the auxiliary tape can be stuck neatly without forming a gap in the adherend. It is possible to completely seal both sides of the body. However, the conductive tape is rarely attached to a completely smooth surface, for example,
It is often attached to a non-smooth surface such as a bent portion of a cathode ray tube or a portion having a step in a printed wiring portion. In a conventional conductive adhesive tape provided with an auxiliary tape made of, for example, a polyester base, when sticking to the bent portion as described above, the length aberration caused by the thickness of the metal foil cannot be absorbed,
Sticking wrinkles occur, and a gap is formed between the adherend and the interface.
Also, when the conductive adhesive tape is attached to a stepped portion, the base material of the auxiliary tape cannot follow the step, and a gap is formed between the tape and the adherend. When the site where such a gap has occurred is exposed to high humidity, the gap may become humid,
It becomes a path for moisture, causing a decrease in adhesive strength, and as a result, a problem arises in that contact failure (poor conduction) occurs.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an excellent adherence to an object having a non-smooth surface such as a bent portion or a step, and exhibit a stable electric conductivity. To provide a conductive adhesive tape capable of exhibiting the following.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object. As a result, when the base material of the auxiliary tape is formed of a plastic film having specific physical properties, the adherend is bent or bent. The present inventors have found that it is possible to follow even if there is a step, and that the sealing property of the conductive adhesive tape main body can be improved, and the present invention has been completed.

That is, the present invention provides a conductive adhesive tape main body in which electrical conductivity is provided between a conductive base material and an adhesive layer provided on one surface of the conductive base material. (A) and an auxiliary tape (B) provided with an adhesive layer on one surface of a base material and formed wider than the conductive adhesive tape main body (A). A conductive adhesive tape in which the surface on the conductive substrate side of the tape body (A) and the surface on the adhesive layer side of the auxiliary tape (B) are bonded together, leaving both sides in the width direction of the auxiliary tape (B) The base material of the auxiliary tape (B) has a tensile modulus of 60
Provided is a conductive adhesive tape made of a plastic film having a kgf / mm ² or less and a stress relaxation rate at the time of 10% stretching of 40% or more.

[0010]

Embodiments of the present invention will be described below with reference to the drawings as necessary. FIG. 1 is a schematic sectional view showing an example of the conductive adhesive tape of the present invention. The conductive adhesive tape T1 includes a conductive adhesive tape main body 3 having an adhesive layer 2 provided on one surface of a conductive base material 1, and an auxiliary tape 6 having an adhesive layer 5 provided on one surface of a base material 4. It is composed of The auxiliary tape 6 is formed wider than the conductive adhesive tape main body 3, and the surface of the conductive adhesive tape main body 3 on the conductive substrate 1 side and the surface of the auxiliary tape 6 on the adhesive layer 5 side are different. The auxiliary tape 6 is stuck to both sides in the width direction. In this example, by adding a conductive filler to the adhesive layer 2 of the conductive adhesive tape body 3, the conductive base material 1 and the adhesive surface of the adhesive layer 2 to be adhered to each other can be formed. Electrical conductivity is provided.

As the conductive substrate 1, any film or sheet having self-supporting properties and showing conductivity may be used.
Preferably, it is a metal foil. Examples of the material of the metal foil include copper, aluminum, nickel, iron, lead, and silver. The thickness of the conductive substrate 1 is not particularly limited, and may be 5
Can be appropriately selected from the range of about 500 μm, but from the viewpoint of the balance between strength and flexibility, about 8 to 200 μm,
Particularly, the thickness is preferably about 10 to 100 μm.

As the adhesive used for the adhesive layer 2 of the conductive adhesive tape body 3, a conventional adhesive can be used, and among them, a pressure-sensitive adhesive is preferable. The pressure-sensitive adhesive is not particularly limited, and known pressure-sensitive adhesives such as rubber-based, acrylic, and silicone-based adhesives can be used. However, from the viewpoint of heat resistance and durability, acrylic pressure-sensitive adhesives are generally used. Agent is used. The thickness of the adhesive layer 2 can be appropriately selected within a range that does not impair the conductivity in the thickness direction, and is, for example, about 3 to 300 μm, and preferably about 5 to 200 μm.

As the conductive filler, a conventional filler can be used. For example, Ni, Fe, Cr, Co, Al,
Examples include metals such as Sb, Mo, Cu, Ag, Pt, and Au, alloys and oxides thereof, and carbon such as carbon black. These can be used alone or in combination of two or more. The filler may be powdery or fibrous.

The adhesive layer 2 further includes a tackifying resin,
Anti-aging agent, UV absorber, coloring agent, filler, flame retardant,
Conventional additives such as an antistatic agent and a rust preventive may be added.

The conductive adhesive tape main body 3 can be obtained by a conventional method used in manufacturing an adhesive tape. For example, a coating solution containing an adhesive such as a pressure-sensitive adhesive and a conductive filler and an appropriate crosslinking agent is applied on release paper to a desired thickness, and dried to form an adhesive layer. The adhesive layer can be obtained by laminating the conductive substrate 1 to the adhesive layer and cutting it to a desired width as required. The release paper can be peeled off at an appropriate time, such as when sticking to an adherend. In addition, the conductive adhesive tape body 3
Can be obtained by directly applying the coating liquid to the conductive substrate 1, drying and cutting as necessary.

The main feature of the present invention is that the auxiliary tape 6
Of the substrate 4, tensile modulus 60 kgf / mm ² or less (e.g. 5~60kgf / mm ^2), and configuration when stretched 10% stress relaxation ratio of a plastic film of 40% or more (e.g., 40% to 95%) In that it is.

The tensile modulus is preferably 5 to 55 k.
gf / mm ² , more preferably 10 to 50 kgf
/ Mm ² . Further, the stress relaxation rate at the time of the 10% stretching is preferably about 50 to 95%, and more preferably about 60 to 90%. Tensile modulus is 60kgf /
If it exceeds ² mm, when the conductive adhesive tape is adhered to an adherend having a bent portion or a step, the auxiliary tape 6 cannot follow the bent portion or the step of the adherend, and the auxiliary tape 6 is not covered with the conductive tape. There is a large gap between the body and the body. The stress relaxation rate is 40%
If it is less than 3, the auxiliary tape 6 floats (peels) from the adherend over time due to the residual stress, and the gap also becomes large. For this reason, the conductive performance is significantly reduced by moisture and humidity.

The tensile modulus of elasticity is determined according to JIS K 712.
This is a value based on the measurement method specified in No. 7 (test piece: 1
No. test piece [width 10mm], tensile speed: 200mm /
Minutes). In addition, the stress relaxation rate at the time of 10% stretching refers to the stress relaxation rate after elongating (stretching) the film to 10% under the tensile elasticity test conditions and allowing the film to stand still for 10 minutes in that state.

The material of the substrate 4 is not particularly limited as long as it exhibits the above-mentioned physical properties. Examples of general-purpose materials include low-density polyethylene, polyethylene / polypropylene blends, soft polyvinyl chloride, nylon 6, And ionomers (eg, a polymer obtained by neutralizing (ionizing) an ethylene-methacrylic acid copolymer with Na and Zn ions). Among them, soft polyvinyl chloride, ionomer and the like are preferable.

The base material 4 includes an antioxidant, an ultraviolet absorber,
Conventional additives such as a coloring agent, a filler, a flame retardant, an antistatic agent, and a rust inhibitor may be added. The thickness of the substrate 4 is not particularly limited, but is preferably about 20 to 200 μm in consideration of the workability of application as a conductive adhesive tape.

The type of the adhesive used for the adhesive layer 5 of the auxiliary tape 6 is not particularly limited, and a conventional adhesive such as a known pressure-sensitive adhesive such as a rubber-based, acrylic-based, or silicone-based adhesive may be used. Although it can be used, an acrylic pressure-sensitive adhesive is preferred from the viewpoint of heat resistance, durability and the like. The thickness of the adhesive layer 5 is not particularly limited, and is a thickness usually adopted as an adhesive sheet, for example, about 5 to 100 μm.

The adhesive layer 5 may contain known additives such as a tackifying resin, an antioxidant, an ultraviolet absorber, a coloring agent, a filler, a flame retardant, an antistatic agent and a rust inhibitor.

The auxiliary tape 6 is obtained by applying a conventional method used for manufacturing an adhesive tape. For example, after a surface treatment (for example, a primer coating treatment, a corona treatment, etc.) is performed on the base material 4 as necessary, a coating solution containing an adhesive is applied and dried, and a desired width is formed as necessary. Can be obtained. The width w2 of the auxiliary tape 6 may be any size as long as it can reliably cover the conductive adhesive tape main body 3 when sticking to the adherend.
Generally, the width w1 of the conductive adhesive tape body 3 is 1.3 to 1.3.
It is about 3.0 times.

The conductive adhesive tape T1 is formed by connecting the surface of the conductive adhesive tape body 3 on the conductive substrate 1 side and the surface of the auxiliary tape 6 on the adhesive layer 5 side to both sides in the width direction of the auxiliary tape 6. It can be manufactured by laminating extra parts.

The conductive adhesive tape T1 is used for electrical continuity at each circuit part of various electronic devices, particularly for grounding. FIG.
FIG. 2 is a schematic cross-sectional view showing a use state of the conductive adhesive tape T1 of FIG. In FIG. 2, reference numeral 7 denotes an adherend, and reference numeral 8 denotes an electrode portion thereof. The conductive adhesive tape T1 is affixed to the adherend 7 at both sides in the width direction of the adhesive layer 2 of the conductive adhesive tape main body 3 and the adhesive layer 5 of the auxiliary tape 6, and the electrode 8 and the conductive substrate Due to the electrical conduction (in the thickness direction) between the materials 1 and the electrical conduction in the longitudinal direction of the conductive substrate 1, the electrode 8
Electrical continuity is established between the electrode 8 and another electrode (not shown) located at a distance from the electrode 8.

According to the conductive adhesive tape T1, the base material 4 of the auxiliary tape 6 is made of a material having a relatively low elasticity and a high stress relaxation rate. Can be followed, and the sealing property of the conductive adhesive tape body 3 having the conductive substrate 1 can be improved. Therefore, intrusion of moisture or moisture into the adhesive interface between the conductive adhesive tape T1 and the adherend 7 can be reliably prevented, and stable conductive performance can be exhibited.

FIG. 3 is a schematic sectional view showing another example of the conductive adhesive tape of the present invention, and FIG. 4 is a schematic sectional view showing the state of use of the conductive adhesive tape of FIG.

This conductive adhesive tape T2 is made of a conductive base material 11
A conductive adhesive tape body 13 having a width w3 in which an adhesive layer 12 is provided on one side of the substrate, and a width in which an adhesive layer 15 is provided on one side of a base material 14
and w4 auxiliary tape 16. Auxiliary tape 16
Is formed wider than the conductive adhesive tape body 13, and the surface of the conductive adhesive tape body 13 on the conductive substrate 11 side,
The surface of the auxiliary tape 16 on the side of the adhesive layer 15 is adhered to the auxiliary tape 16 except for both sides in the width direction.

In this example, the conductive adhesive tape body 13
A conductive portion 17 extending from the conductive base material 11, penetrating the adhesive layer 12, and having a terminal portion 18 at the tip thereof is formed, and the conductive portion 17 allows the conductive base material 11 and the adhesive layer 12 to be formed. Electrical continuity is imparted to the attachment surface. The conductive adhesive tape T2 and the conductive adhesive tape T1 shown in FIG. 1 are provided between the conductive base material and the surface of the adhesive layer (the surface to be adhered to the adherend) in the conductive adhesive tape body. Only the means for imparting electrical conductivity is different, and the other points are common.

The conductive adhesive tape body 13 is manufactured by
It can be produced by the method described in JP-A-46980 or JP-A-8-185714. For example, an adhesive such as a pressure-sensitive adhesive, and a coating liquid containing a crosslinking agent or an additive, if necessary, are coated on the surface of the conductive substrate 11 to a desired thickness, and dried. After forming the adhesive layer 12, the conductive base material 11 is formed using a punch-shaped male type and a die female type.
Is drawn into a cylindrical shape to form a conductive portion 17, and then the tip of the cylindrical portion is horizontally bent outward by a press to form a terminal portion.
It can be manufactured by forming 18. Usually, a plurality of conductive portions 17 are formed at appropriate intervals.

The conductive adhesive tape T2 is composed of the adhesive layer 12 of the conductive adhesive tape body 13 and the adhesive layer 15 of the auxiliary tape 16.
Of the electrodes 8 are adhered to the adherend 7 at both sides in the width direction.
The electrode 8 is disposed at a position separated from the electrode 8 by electrical conduction in the thickness direction via the conduction portion 17 between the conductive substrate 11 and the electrical conduction in the longitudinal direction of the conductive substrate 11. Electrical continuity is established between other electrodes and the like (not shown).

In the conductive adhesive tape T2 as well, since the base material 14 of the auxiliary tape 16 is made of a material having a relatively low elasticity and a high stress relaxation rate, the conductive adhesive tape T1
The same operation and effect as described above can be obtained.

[0033]

According to the conductive adhesive tape of the present invention, even when the adherend has a non-smooth surface such as a bent portion or a step, it exhibits excellent moisture resistance and exhibits stable electrical conductivity. Can be expressed.

[0034]

Next, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples. Hereinafter, “parts” means “parts by weight”.

Reference Example 1 85 parts of 2-ethylhexyl acrylate, vinyl acetate 1
0 part, 5 parts of acrylic acid, 0.1 part of N, N'-azobisisobutyronitrile and 200 parts of toluene are placed in a flask, and after purging with nitrogen, the mixture is stirred and mixed at 60 ° C. for 20 hours to proceed the copolymerization reaction. Then, an acrylic copolymer solution was prepared.

Reference Example 2 The solid content of 100% was added to the copolymer solution obtained in Reference Example 1.
To 35 parts, 35 parts of a rosin-based tackifying resin, 5 parts of carbon black, 30 parts of nickel powder, 0.15 part of an aluminum chelate dispersant, and 3 parts of a tolylene diisocyanate adduct of trimethylolpropane were added. An appropriate amount of toluene was added for adjustment and stirred to prepare a conductive filler-containing acrylic pressure-sensitive adhesive solution.

Reference Example 3 The solid content of 100% was added to the copolymer solution obtained in Reference Example 1.
To 35 parts, 35 parts of a rosin-based tackifying resin and 3 parts of a tolylene diisocyanate adduct of trimethylolpropane were added, and an appropriate amount of toluene was added for viscosity adjustment, followed by stirring to prepare an acrylic pressure-sensitive adhesive solution. did.

REFERENCE EXAMPLE 4 The conductive filler-containing acrylic pressure-sensitive adhesive solution obtained in Reference Example 2 was coated on a release paper and dried by heating to a thickness of 45 mm.
An adhesive layer having a thickness of μm was formed, and this was adhered to a rolled copper foil having a thickness of 35 μm to obtain a conductive adhesive tape body of the present invention.

Reference Example 5 The acrylic pressure-sensitive adhesive solution obtained in Reference Example 3 was coated on release paper and dried by heating to form an adhesive layer having a thickness of 45 μm, which was then adhered to a 35 μm rolled copper foil. I combined. Then, a hole (about 0.5 to 1...) Penetrating the adhesive layer from the copper foil side.
Holes having a size of 0 mm) were formed at intervals of 3 mm, and terminal portions were formed on the surface of the adhesive layer to obtain a conductive adhesive tape body of the present invention.

Reference Example 6 A commercially available soft vinyl chloride film having a thickness of 60 μm (tensile elastic modulus: 40 kgf / mm ² , stress relaxation rate at 10% stretching: 8)
(0%) was coated with a primer for vinyl chloride and dried, and then the acrylic pressure-sensitive adhesive solution of Reference Example 3 was applied and dried so as to have a dry thickness of 25 μm to obtain an auxiliary tape.

Reference Example 7 An ionomer resin [Hylamine 1705, manufactured by Du Pont-Mitsui Chemicals Co., Ltd.] was extruded to a thickness of 40 μm, and one surface was subjected to corona treatment. This film (tensile elastic modulus 2
8 kgf / mm ² , stress relaxation rate at 10% stretching 64%)
The acrylic pressure-sensitive adhesive solution of Reference Example 3 was dried to a thickness of 25.
It was coated and dried to a thickness of μm to obtain an auxiliary tape.

Reference Example 8 A commercially available polypropylene / polyethylene blend film having a thickness of 40 μm (tensile elastic modulus: 30 kgf / mm ² , 10
55% stress relaxation rate at the time of stretching, corona treated on one side)
Then, the acrylic pressure-sensitive adhesive solution of Reference Example 3 was dried to a dry thickness of 2
An auxiliary tape was formed by coating and drying to a thickness of 5 μm.

Reference Example 9 An acrylic pressure-sensitive film of Reference Example 3 was applied to a commercially available low-density polyethylene film having a thickness of 40 μm (tensile elasticity: 20 kgf / mm ² , stress relaxation rate at the time of 10% stretching: 47%, and one-sided corona treatment). The adhesive solution was applied to a dry thickness of 25 μm and dried to obtain an auxiliary tape.

Reference Example 10 The acrylic pressure-sensitive adhesive of Reference Example 3 was applied to a commercially available stretched polypropylene film having a thickness of 40 μm (tensile modulus of elasticity: 200 kgf / mm ² , stress relaxation rate at the time of stretching by 10%, 44% subjected to corona treatment on one side). The agent solution was applied to a dry thickness of 25 μm and dried to obtain an auxiliary tape.

Reference Example 11 A commercially available polyester film having a thickness of 50 μm (tensile elastic modulus: 400 kgf / mm ² , stress relaxation rate at the time of 10% stretching: 3)
(6%), the acrylic pressure-sensitive adhesive solution of Reference Example 3 was applied to a dry thickness of 25 μm and dried to obtain an auxiliary tape.

Reference Example 12 Acrylic pressure-sensitive material of Reference Example 3 was applied to a commercially available unstretched polypropylene film having a thickness of 40 μm (tensile elastic modulus 90 kgf / mm ² , stress relaxation rate at the time of stretching 10%, 55%, and one-sided corona treatment). The adhesive solution was applied to a dry thickness of 25 μm and dried to obtain an auxiliary tape.

Example 1 The auxiliary tape 25 mm width of Reference Example 6 was adhered to the conductive adhesive tape body 15 mm width copper foil side of Reference Example 4 so that the center lines of both tapes were aligned. A tape was made.

Example 2 A conductive adhesive tape of the present invention was produced in the same manner as in Example 1 except that the auxiliary tape of Reference Example 9 was used instead of the auxiliary tape of Reference Example 6.

Example 3 A conductive adhesive tape of the present invention was bonded to the conductive adhesive tape of the present invention by bonding the auxiliary tape 25 mm wide of Reference Example 6 to the silver foil side of the conductive adhesive tape body of Reference Example 5 having a width of 15 mm so that the center lines of both tapes were aligned. Was prepared.

Example 4 A conductive adhesive tape of the present invention was produced in the same manner as in Example 3 except that the auxiliary tape of Reference Example 7 was used instead of the auxiliary tape of Reference Example 6.

Example 5 A conductive adhesive tape of the present invention was produced in the same manner as in Example 3 except that the auxiliary tape of Reference Example 8 was used instead of the auxiliary tape of Reference Example 6.

Example 6 A conductive adhesive tape of the present invention was produced in the same manner as in Example 3 except that the auxiliary tape of Reference Example 9 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 1 A conductive adhesive tape was produced in the same manner as in Example 1 except that the auxiliary tape of Reference Example 10 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 2 A conductive adhesive tape was produced in the same manner as in Example 1 except that the auxiliary tape of Reference Example 11 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 3 A conductive adhesive tape was produced in the same manner as in Example 1 except that the auxiliary tape of Reference Example 12 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 4 A conductive adhesive tape was produced in the same manner as in Example 3 except that the auxiliary tape of Reference Example 10 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 5 A conductive adhesive tape was produced in the same manner as in Example 3, except that the auxiliary tape of Reference Example 11 was used instead of the auxiliary tape of Reference Example 6.

Comparative Example 6 A conductive adhesive tape was produced in the same manner as in Example 3 except that the auxiliary tape of Reference Example 12 was used instead of the auxiliary tape of Reference Example 6.

Experimental Example (Measurement of Contact Resistance Value) A double-sided tape having a thickness of 50 μm was attached to one surface of a copper foil having a length of 50 mm, a width of 5 mm, and a thickness of 35 μm. Pasting, step 85μ
m. Similarly, a double-sided tape having a thickness of 100 μm was attached to one surface of the copper foil, and a step of 135 μm was formed.
Was formed. Next, each of the conductive adhesive tapes obtained in Examples 1 to 6 and Comparative Examples 1 to 6 was
Cut into 30 mm, and in an atmosphere of 23 ° C. and 65% relative humidity, 5 k
g It was pressed with a rubber roller and adhered.

The resistance between the two electrodes formed in parallel was measured with a multi-tester, and was used as an initial value. Next, the entire glass plate to which the conductive adhesive tape was adhered was put into an atmosphere at 40 ° C. and a relative humidity of 92% for 100 hours, and then left under an atmosphere at a temperature of 23 ° C. and a relative humidity of 65% for 30 minutes. Was measured. The results are shown in Table 1.

[Table 1] As is clear from Table 1, the conductive adhesive tapes of Examples 1 to 6 exhibit excellent moisture resistance and can exhibit stable conductive performance even when the electrode portion has a step.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a conductive adhesive tape of the present invention.

FIG. 2 is a schematic sectional view showing a use state of the conductive adhesive tape of FIG. 1;

FIG. 3 is a schematic sectional view showing another example of the conductive adhesive tape of the present invention.

FIG. 4 is a schematic sectional view showing a use state of the conductive adhesive tape of FIG. 3;

[Explanation of symbols]

 T1, T2 conductive adhesive tape 1,11 conductive base material 2,12 adhesive layer 3,13 conductive adhesive tape body 4,14 base material 5,15 adhesive layer 6,16 auxiliary tape 7 adherend 8 electrode Part 17 Conducting part 18 Terminal part

Claims (1)

[Claims] 1. A conductive adhesive tape main body (A) having electrical conductivity provided between a conductive substrate and an adhesive layer provided on one surface of the conductive substrate. And an auxiliary tape (B) provided with an adhesive layer on one side of the base material and formed wider than the conductive adhesive tape body (A), and the conductive adhesive tape body (A )
A conductive adhesive tape in which the surface on the conductive base material side and the surface on the adhesive layer side of the auxiliary tape (B) are stuck together over both sides in the width direction of the auxiliary tape (B), A conductive adhesive tape in which the base material of the auxiliary tape (B) is formed of a plastic film having a tensile modulus of 60 kgf / mm ² or less and a stress relaxation rate at the time of 10% stretching of 40% or more.