JP6969172B2

JP6969172B2 - Conductive adhesive sheet

Info

Publication number: JP6969172B2
Application number: JP2017118639A
Authority: JP
Inventors: 大輔山川; 優山崎; 晃山上
Original assignee: DIC Corp
Current assignee: DIC Corp
Priority date: 2017-06-16
Filing date: 2017-06-16
Publication date: 2021-11-24
Anticipated expiration: 2037-06-16
Also published as: JP2019001930A

Description

本発明は、導電性基材と、導電性粒子を含有する粘着剤層とを有する導電性粘着シートに関する。 The present invention relates to a conductive pressure-sensitive adhesive sheet having a conductive base material and a pressure-sensitive adhesive layer containing conductive particles.

導電性粘着シートはその取扱いの容易さから、電気、電子機器等から輻射する不要な漏洩電磁波のシールド用、他の電気、電子機器より発生する有害な空間電磁波のシールド用、静電気帯電防止の接地用などに用いられており、近年の電気・電子機器の小型化、薄膜化に伴い、これらに用いられる導電性粘着シートも薄膜化が求められている。 Due to its ease of handling, the conductive adhesive sheet is used for shielding unnecessary leaked electromagnetic waves radiated from electric and electronic devices, for shielding harmful spatial electromagnetic waves generated by other electric and electronic devices, and grounding to prevent static electricity. It is used for various purposes, and with the recent miniaturization and thinning of electric and electronic devices, the conductive adhesive sheet used for these is also required to be thinned.

当該導電性粘着シートとしては、導電性基材上に、導電性フィラーを粘着性物質中に分散させた導電性粘着剤からなる粘着剤層を有する粘着シートが開示されている（特許文献１〜２参照）。これら粘着シートは、好適な導電性と接着性とを有することが開示されている。 As the conductive pressure-sensitive adhesive sheet, a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of a conductive pressure-sensitive adhesive in which a conductive filler is dispersed in a pressure-sensitive adhesive is disclosed on a conductive base material (Patent Documents 1 to 1). 2). It is disclosed that these pressure-sensitive adhesive sheets have suitable conductivity and adhesiveness.

しかし、近年の小型電子端末等において、電子基板の小スペース化に伴い、粘着シートの接着面積が小さくなっているため、経時で剥がれが生じやすく、導電性が低下する問題があった。 However, in recent small electronic terminals and the like, the adhesive area of the adhesive sheet has become smaller due to the smaller space of the electronic substrate, so that there is a problem that peeling easily occurs over time and the conductivity is lowered.

また、電子基板の凹凸部に粘着シートを貼り合せた際には、経時で剥がれ生じ、導電性が低下する問題があった。 Further, when the adhesive sheet is attached to the uneven portion of the electronic substrate, there is a problem that the adhesive sheet is peeled off with time and the conductivity is lowered.

特開２００４−２６３０３０号公報Japanese Unexamined Patent Publication No. 2004-263030 特開２００９−７９１２７号公報Japanese Unexamined Patent Publication No. 2009-79127

本発明が解決しようとする課題は、接着面積が小面積で且つ凹凸部に貼り合せても、良好な接着性、導電性、リワーク性を有し、経時で導電性が低下し難い導電性粘着シートを提供することにある。 The problem to be solved by the present invention is that the adhesive area is small and the conductive adhesive has good adhesiveness, conductivity, and reworkability even when bonded to the uneven portion, and the conductivity does not easily decrease with time. To provide a sheet.

本発明においては導電性基材と導電性粘着剤層とを有する導電性粘着シートであって、前記導電性粘着剤層が、（メタ）アクリル系共重合体、架橋剤及び導電性粒子を含有する（メタ）アクリル系粘着剤組成物からなり、前記（メタ）アクリル系共重合体が、重量平均分子量が５０万〜２００万のカルボキシル基含有（メタ）アクリル系共重合体（Ａ）と、重量平均分子量が５０００〜１０万の窒素原子含有（メタ）アクリル系共重合体（Ｂ）とを含有し、前記（メタ）アクリル系粘着剤組成物中の窒素原子含有（メタ）アクリル系共重合体（Ｂ）の質量比が５％〜３０％であることを特徴とする導電性粘着シートにより、上記課題を解決した。 In the present invention, the conductive pressure-sensitive adhesive sheet has a conductive base material and a conductive pressure-sensitive adhesive layer, and the conductive pressure-sensitive adhesive layer contains a (meth) acrylic copolymer, a cross-linking agent, and conductive particles. The (meth) acrylic copolymer comprises a carboxyl group-containing (meth) acrylic copolymer (A) having a weight average molecular weight of 500,000 to 2,000,000. It contains a nitrogen atom-containing (meth) acrylic copolymer (B) having a weight average molecular weight of 5,000 to 100,000, and has a nitrogen atom-containing (meth) acrylic copolymer weight in the (meth) acrylic pressure-sensitive adhesive composition. The above-mentioned problems are solved by the conductive pressure-sensitive adhesive sheet characterized in that the mass ratio of the coalesced (B) is 5% to 30%.

本発明の導電性薄型粘着シートは、薄型でありながら、被着体への良好な接着性と導電性とを有するため、電気、電子機器等に用いる電磁波のシールド用、他の電気、電子機器より発生する有害な空間電磁波のシールド用、静電気帯電防止の接地固定用として有用である。特に、薄型化が進み、筐体内での容積制限が厳しい携帯電子機器用途に好適に適用できる。特に、小型電子端末の内蔵部品に貼り付けて使用させるのに好適である。 Since the conductive thin adhesive sheet of the present invention is thin and has good adhesion and conductivity to an adherend, it is used for shielding electromagnetic waves used in electric and electronic devices, and other electric and electronic devices. It is useful for shielding more harmful spatial electromagnetic waves and for fixing the ground to prevent static electricity. In particular, it can be suitably applied to portable electronic equipment applications in which the thickness is increasing and the volume limitation in the housing is strict. In particular, it is suitable for being used by being attached to a built-in component of a small electronic terminal.

本発明の導電性粘着シートの構成例を示す概略図である。It is a schematic diagram which shows the structural example of the conductive pressure-sensitive adhesive sheet of this invention. 本発明の導電性粘着シートの構成例を示す概略図である。It is a schematic diagram which shows the structural example of the conductive pressure-sensitive adhesive sheet of this invention. 本発明の導電性粘着シートに好適に用いられる数珠状導電性粒子の一例の顕微鏡写真である。It is a micrograph of an example of the beaded conductive particles preferably used for the conductive pressure-sensitive adhesive sheet of the present invention. 本発明の導電性粘着シートの導電性評価を表す模式図である。It is a schematic diagram which shows the conductivity evaluation of the conductive pressure-sensitive adhesive sheet of this invention.

本発明の導電性粘着シートは、導電性基材と導電性粘着剤層とを有する導電性粘着シートであって、前記導電性粘着剤層が、（メタ）アクリル系共重合体、架橋剤及び導電性粒子を含有する（メタ）アクリル系粘着剤組成物からなり、前記（メタ）アクリル系共重合体が、重量平均分子量が５０万〜２００万のカルボキシル基含有（メタ）アクリル系共重合体（Ａ）と、重量平均分子量が５０００〜１０万の窒素原子含有（メタ）アクリル系共重合体（Ｂ）とを含有し、前記（メタ）アクリル系粘着剤組成物中の窒素原子含有（メタ）アクリル系共重合体（Ｂ）の質量比が５％〜３０％であることを特徴とする導電性粘着シートである。 The conductive pressure-sensitive adhesive sheet of the present invention is a conductive pressure-sensitive adhesive sheet having a conductive base material and a conductive pressure-sensitive adhesive layer, wherein the conductive pressure-sensitive adhesive layer is a (meth) acrylic copolymer, a cross-linking agent, and a conductive pressure-sensitive adhesive layer. The (meth) acrylic copolymer comprises a (meth) acrylic pressure-sensitive adhesive composition containing conductive particles, and the (meth) acrylic copolymer is a carboxyl group-containing (meth) acrylic copolymer having a weight average molecular weight of 500,000 to 2 million. It contains (A) and a nitrogen atom-containing (meth) acrylic copolymer (B) having a weight average molecular weight of 5,000 to 100,000, and contains nitrogen atoms (meth) in the (meth) acrylic pressure-sensitive adhesive composition. ) A conductive pressure-sensitive adhesive sheet characterized in that the mass ratio of the acrylic copolymer (B) is 5% to 30%.

以下に、本発明の導電性粘着シートを、その構成要素に基づいて、更に詳しく説明する。なお、本発明における「シート」とは、少なくとも一層の導電性粘着剤の薄層を導電性基材上、あるいは剥離シート上に設けた形態を意味し、例えば、毎葉、ロール状、あるいは薄板状、帯状（テープ状）等の製品形態すべてを含む。 Hereinafter, the conductive pressure-sensitive adhesive sheet of the present invention will be described in more detail based on its constituent elements. The "sheet" in the present invention means a form in which at least one thin layer of a conductive pressure-sensitive adhesive is provided on a conductive base material or a release sheet, and is, for example, every leaf, roll-shaped, or thin plate. Includes all product forms such as shape and band shape (tape shape).

（導電性粘着剤層）
本発明の導電性粘着シートに使用する導電性粘着剤層は、（メタ）アクリル系共重合体、架橋剤及び導電性粒子を含有する（メタ）アクリル系粘着剤組成物からなり、前記（メタ）アクリル系共重合体が、重量平均分子量が５０万〜２００万のカルボキシル基（メタ）アクリル系共重合体（Ａ）と、重量平均分子量が５０００〜１０万の窒素原子含有（メタ）アクリル系共重合体（Ｂ）とを含有するものである。 (Conductive adhesive layer)
The conductive pressure-sensitive adhesive layer used in the conductive pressure-sensitive adhesive sheet of the present invention comprises a (meth) acrylic pressure-sensitive adhesive composition containing a (meth) acrylic copolymer, a cross-linking agent and conductive particles, and is composed of the above-mentioned (meth) acrylic pressure-sensitive adhesive composition. ) Acrylic copolymer contains a carboxyl group (meth) acrylic copolymer (A) having a weight average molecular weight of 500,000 to 2 million and a nitrogen atom-containing (meth) acrylic copolymer having a weight average molecular weight of 5,000 to 100,000. It contains the copolymer (B).

（カルボキシル基含有（メタ）アクリル系共重合体（Ａ））
本発明に用いられるカルボキシル基含有（メタ）アクリル系共重合体（Ａ）は、炭素数２〜１４の（メタ）アクリレートモノマーを主成分とし、カルボキシル基含有（メタ）アクリレートモノマーが共重合された重合体である。当該炭素数２〜１４の（メタ）アクリレートモノマーを主成分とすることで、金属への初期接着性と、剥がれに必要な凝集力を導電性粘着剤層に付与できる。 (Carboxyl group-containing (meth) acrylic copolymer (A))
The carboxyl group-containing (meth) acrylic copolymer (A) used in the present invention contains a (meth) acrylate monomer having 2 to 14 carbon atoms as a main component, and the carboxyl group-containing (meth) acrylate monomer is copolymerized. It is a polymer. By using the (meth) acrylate monomer having 2 to 14 carbon atoms as a main component, it is possible to impart the initial adhesiveness to the metal and the cohesive force required for peeling to the conductive pressure-sensitive adhesive layer.

なお、本明細書においてはアクリル酸及びメタアクリル酸を総称して（メタ）アクリル酸と標記し、これらの誘導体についても同様に表記する。 In this specification, acrylic acid and methacrylic acid are collectively referred to as (meth) acrylic acid, and these derivatives are also referred to in the same manner.

炭素数２〜１４の（メタ）アクリレートモノマーとしては、具体的には、エチルアクリレート、ｎ−プロピルアクリレート、イソプロピルアクリレート、ｎ−ブチルアクリレート、ｓｅｃ−ブチルアクリレート、ｔ−ブチルアクリレート、ｎ−ヘキシルアクリレート、シクロヘキシルアクリレート、ｎ−オクチルアクリレート、イソオクチルアクリレート、２−エチルヘキシルアクリレート、イソノニルアクリレート、イソデシルアクリレート、ラウリルアクリレート、メチルメタクリレート、エチルメタクリレート、ｎ−プロピルメタクリレート、イソプロピルメタクリレート、ｎ−ブチルメタクリレート、ｓｅｃ−ブチルメタクリレート、ｔ−ブチルメタクリレート、ｎ−ヘキシルメタクリレート、シクロヘキシルメタクリレート、ｎ−オクチルメタクリレート、イソオクチルメタクリレート、２−エチルヘキシルメタクリレート、イソノニルメタクリレート、イソデシルメタクリレート、ラウリルメタクリレート等が挙げられる。 Specific examples of the (meth) acrylate monomer having 2 to 14 carbon atoms include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate, t-butyl acrylate, and n-hexyl acrylate. Cyclohexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, isodecyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, sec-butyl Examples thereof include methacrylate, t-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate, isononyl methacrylate, isodecyl methacrylate, and lauryl methacrylate.

そのなかでも、炭素数が４〜９のアルキル側鎖を有する（メタ）アクリレートモノマーは炭素数が４〜９のアルキル側鎖を有するアクリレートモノマーが好ましく、炭素数が４〜９のアルキル側鎖を有するアクリレートモノマーがより好ましい。なかでもｎ−ブチルアクリレート、２−エチルヘキシルアクリレートが特に好ましい。当該範囲の炭素数のアルキル側鎖を有する（メタ）アクリレートモノマーを使用することで、金属への初期接着性と、剥がれに必要な凝集力を導電性粘着剤層に付与できる。 Among them, the (meth) acrylate monomer having an alkyl side chain having 4 to 9 carbon atoms is preferably an acrylate monomer having an alkyl side chain having 4 to 9 carbon atoms, and an alkyl side chain having 4 to 9 carbon atoms is preferable. The acrylate monomer having is more preferable. Of these, n-butyl acrylate and 2-ethylhexyl acrylate are particularly preferable. By using a (meth) acrylate monomer having an alkyl side chain having an alkyl side chain having a carbon number in the range, the conductive pressure-sensitive adhesive layer can be provided with initial adhesiveness to a metal and cohesive force required for peeling.

カルボキシル基含有（メタ）アクリル系共重合体（Ａ）中の炭素数２〜１４の（メタ）アクリレートモノマーの含有量は、９０〜９９質量％とすることが好ましく、９０〜９６質量％にすることがより好ましい。当該範囲のカルボキシル基含有（メタ）アクリル系共重合体（Ａ）中の上記炭素数２〜１４の（メタ）アクリレートモノマーの含有量にすることで、金属への初期接着性と、剥がれに必要な凝集力を導電性粘着剤層に付与できる。 The content of the (meth) acrylate monomer having 2 to 14 carbon atoms in the carboxyl group-containing (meth) acrylic copolymer (A) is preferably 90 to 99% by mass, preferably 90 to 96% by mass. Is more preferable. By setting the content of the (meth) acrylate monomer having 2 to 14 carbon atoms in the carboxyl group-containing (meth) acrylic copolymer (A) in the above range, it is necessary for initial adhesion to the metal and peeling. A strong cohesive force can be imparted to the conductive pressure-sensitive adhesive layer.

カルボキシル基含有（メタ）アクリレートモノマーとしては、アクリル酸、メタアクリル酸、イタコン酸、マレイン酸、クロトン酸、アクリル酸ダイマー、エチレンオキサイド変性コハク酸アクリレート等が挙げられる。なかでも汎用性が高いことからアクリル酸が好ましい。 Examples of the carboxyl group-containing (meth) acrylate monomer include acrylic acid, methacrylic acid, itaconic acid, maleic acid, crotonic acid, acrylic acid dimer, and ethylene oxide-modified succinic acid acrylate. Of these, acrylic acid is preferable because of its high versatility.

カルボキシル基含有（メタ）アクリル系共重合体（Ａ）を構成する単量体成分中のカルボキシル基含有（メタ）アクリレートモノマーの含有量は、当該共重合体を構成する単量体成分の総量に対し、１〜２０質量％とすることが好ましく、４〜２０質量％にすることがより好ましい。当該範囲の含有量にすることで、金属への初期接着性と、剥がれに必要な凝集力を導電性粘着剤層に付与できる。 The content of the carboxyl group-containing (meth) acrylate monomer in the monomer component constituting the carboxyl group-containing (meth) acrylic copolymer (A) is the total amount of the monomer components constituting the copolymer. On the other hand, it is preferably 1 to 20% by mass, and more preferably 4 to 20% by mass. By setting the content in this range, the initial adhesiveness to the metal and the cohesive force required for peeling can be imparted to the conductive pressure-sensitive adhesive layer.

また、架橋剤と好適に架橋反応させることにより粘着剤層の凝集力を高くするために、架橋剤と反応する官能基を有するビニルモノマーを使用することも好ましい。架橋剤と反応する官能基を有するビニルモノマーとしては、特に限定されないが、２−ヒドロキシエチルアクリレート、２−ヒドロキシエチルメタクリレート、４−ヒドロキシブチルアクリレート等の水酸基含有ビニルモノマー等が挙げられる。中でも、４−ヒドロキシブチルアクリレートが好ましい。官能基を有するビニルモノマーの使用量はアクリル共重合体を構成するモノマー成分中の０．０１質量％〜１．０質量％であることが好ましく、０．０３〜０．５質量％であることが特に好ましい。 It is also preferable to use a vinyl monomer having a functional group that reacts with the cross-linking agent in order to increase the cohesive force of the pressure-sensitive adhesive layer by subjecting it to a cross-linking reaction with the cross-linking agent. The vinyl monomer having a functional group that reacts with the cross-linking agent is not particularly limited, and examples thereof include hydroxyl group-containing vinyl monomers such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and 4-hydroxybutyl acrylate. Of these, 4-hydroxybutyl acrylate is preferable. The amount of the vinyl monomer having a functional group to be used is preferably 0.01% by mass to 1.0% by mass, preferably 0.03 to 0.5% by mass in the monomer components constituting the acrylic copolymer. Is particularly preferable.

当該カルボキシル基含有（メタ）アクリル系共重合体（Ａ）の重量平均分子量Ｍｗは５０万〜２００万であるが、６０万〜１８０万が好ましく、７０万〜１６０万がよりに好ましい。当該カルボキシル基含有（メタ）アクリル酸エステル共重合体（Ａ）の重量平均分子量Ｍｗが上記範囲内だと、金属への初期接着性と、剥がれに必要な凝集力を導電性粘着剤層に付与できる。 The weight average molecular weight Mw of the carboxyl group-containing (meth) acrylic copolymer (A) is 500,000 to 2,000,000, preferably 600,000 to 1.8 million, more preferably 700,000 to 1.6 million. When the weight average molecular weight Mw of the carboxyl group-containing (meth) acrylic acid ester copolymer (A) is within the above range, the conductive pressure-sensitive adhesive layer is imparted with initial adhesiveness to the metal and cohesive force required for peeling. can.

なお、本発明では、当該カルボキシル基含有（メタ）アクリル系共重合体（Ａ）の重量平均分子量Ｍｗは、ゲルパーミエーションクロマトグラフ（ＧＰＣ）により測定することができる。より具体的には、ＧＰＣ測定装置として、東ソー株式会社製「ＳＣ８０２０」を用いて、ポリスチレン換算値により、次のＧＰＣ測定条件で測定して求めることができる。
（ＧＰＣの測定条件）
・サンプル濃度：０．５重量％（テトラヒドロフラン溶液）
・サンプル注入量：１００μＬ
・溶離液：テトラヒドロフラン（ＴＨＦ）
・流速：１．０ｍＬ／ｍｉｎ
・カラム温度（測定温度）：４０℃
・カラム：東ソー株式会社製「ＴＳＫｇｅｌＧＭＨＨＲ−Ｈ」
・検出器：示差屈折 In the present invention, the weight average molecular weight Mw of the carboxyl group-containing (meth) acrylic copolymer (A) can be measured by a gel permeation chromatograph (GPC). More specifically, it can be obtained by measuring with the following GPC measuring conditions by the polystyrene conversion value using "SC8020" manufactured by Tosoh Corporation as a GPC measuring device.
(GPC measurement conditions)
-Sample concentration: 0.5% by weight (tetrahydrofuran solution)
-Sample injection amount: 100 μL
-Eluent: Tetrahydrofuran (THF)
・ Flow velocity: 1.0 mL / min
-Column temperature (measurement temperature): 40 ° C
-Column: "TSKgel GMHR-H" manufactured by Tosoh Corporation
・ Detector: Differential refractometer

（窒素原子含有（メタ）アクリル系共重合体（B））
本発明に用いられる窒素原子含有（メタ）アクリル系共重合体（Ｂ）は、炭素数１〜８の（メタ）アクリレートモノマーを主成分とし、窒素原子含有ビニルモノマーが共重合された重合体である。当該炭素数１〜８の（メタ）アクリレートを主成分とすることで、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。また、窒素原子含有ビニルモノマーを共重合することで、カルボキシル基含有（メタ）アクリル系共重合体（Ａ）との相互作用を形成し、優れた凝集力を導電性粘着剤層に付与できる。 (Nitrogen atom-containing (meth) acrylic copolymer (B))
The nitrogen atom-containing (meth) acrylic copolymer (B) used in the present invention is a polymer obtained by copolymerizing a (meth) acrylate monomer having 1 to 8 carbon atoms with a nitrogen atom-containing vinyl monomer as a main component. be. By using the (meth) acrylate having 1 to 8 carbon atoms as a main component, it is possible to impart the cohesive force necessary for suppressing peeling over time to the conductive pressure-sensitive adhesive layer. Further, by copolymerizing the nitrogen atom-containing vinyl monomer, an interaction with the carboxyl group-containing (meth) acrylic copolymer (A) can be formed, and excellent cohesive force can be imparted to the conductive pressure-sensitive adhesive layer.

炭素数１〜８の（メタ）アクリレートモノマーとしては、具体的には、メチルアクリレート、エチルアクリレート、ｎ−プロピルアクリレート、イソプロピルアクリレート、ｎ−ブチルアクリレート、ｓｅｃ−ブチルアクリレート、ｔ−ブチルアクリレート、ｎ−ヘキシルアクリレート、シクロヘキシルアクリレート、ｎ−オクチルアクリレート、イソオクチルアクリレート、２−エチルヘキシルアクリレート、メチルメタクリレート、エチルメタクリレート、ｎ−プロピルメタクリレート、イソプロピルメタクリレート、ｎ−ブチルメタクリレート、ｓｅｃ−ブチルメタクリレート、ｔ−ブチルメタクリレート、ｎ−ヘキシルメタクリレート、シクロヘキシルメタクリレート、ｎ−オクチルメタクリレート、イソオクチルメタクリレート、２−エチルヘキシルメタクリレート等が挙げられる。 Specific examples of the (meth) acrylate monomer having 1 to 8 carbon atoms include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate, t-butyl acrylate, and n-. Hexyl acrylate, cyclohexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, n -Hexyl methacrylate, cyclohexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate and the like can be mentioned.

その中でも、炭素数が１〜４のアルキル側鎖を有するメタクリレートが好ましい。なかでもメチルメタクリレートが特に好ましい。当該範囲の炭素数のアルキル側鎖を有するメタアクリル酸アルキルエステル単量体を使用することで、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 Among them, methacrylate having an alkyl side chain having 1 to 4 carbon atoms is preferable. Of these, methyl methacrylate is particularly preferable. By using the methacrylic acid alkyl ester monomer having an alkyl side chain having an alkyl number in the above range, the cohesive force required for suppressing peeling over time can be imparted to the conductive pressure-sensitive adhesive layer.

（メタ）アクリル系共重合体（Ｂ）を構成する単量体成分中の炭素数１〜８の（メタ）アクリレートモノマーの含有量は、７０〜９９質量％とすることが好ましく、９０〜９８質量％とすることがより好ましい。当該範囲内の（メタ）アクリル系共重合体（Ｂ）中の上記炭素数１〜８の（メタ）アクリル酸エステル単量体の含有量にすることで、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 The content of the (meth) acrylate monomer having 1 to 8 carbon atoms in the monomer component constituting the (meth) acrylic copolymer (B) is preferably 70 to 99% by mass, preferably 90 to 98. It is more preferable to use% by mass. In order to suppress peeling over time by setting the content of the (meth) acrylic acid ester monomer having 1 to 8 carbon atoms in the (meth) acrylic copolymer (B) within the range. The required cohesive force can be imparted to the conductive pressure-sensitive adhesive layer.

窒素原子含有（メタ）アクリル系共重合体（Ｂ）を構成する単量体成分中の炭素数１〜８の（メタ）アクリレートモノマーの含有量は、７０〜９９質量％とすることが好ましく、９０〜９８質量％とすることがより好ましい。当該範囲内の窒素原子含有（メタ）アクリル系共重合体（Ｂ）中の上記炭素数１〜８の（メタ）アクリレートモノマーの含有量にすることで、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 The content of the (meth) acrylate monomer having 1 to 8 carbon atoms in the monomer component constituting the nitrogen atom-containing (meth) acrylic copolymer (B) is preferably 70 to 99% by mass. It is more preferably 90 to 98% by mass. It is necessary to suppress peeling over time by setting the content of the (meth) acrylate monomer having 1 to 8 carbon atoms in the nitrogen atom-containing (meth) acrylic copolymer (B) within the range. A strong cohesive force can be imparted to the conductive pressure-sensitive adhesive layer.

窒素原子含有ビニルモノマーとしては、窒素原子を含有し、上記炭素数１〜８の（メタ）アクリレートモノマーとの共重合が可能であれば問題ないが、例えば、アミノ基含有モノマー、アミド基含有モノマー、窒素系複素環含有モノマー、シアノ基含有モノマー、イミド基含有モノマー等が挙げられる。これらモノマーとしては、例えば、アミノ基含有モノマーとしては、（メタ）アクリル酸アミノメチル、（メタ）アクリル酸アミノエチル、（メタ）アクリル酸アミノプロピル、（メタ）アクリル酸アミノイソプロピル等の（メタ）アクリル酸アミノアルキルや、（メタ）アクリル酸（Ｎ−置換）アミノアルキルなどが挙げられる。前記（メタ）アクリル酸（Ｎ−置換）アミノアルキルとしては、例えば、（メタ）アクリル酸Ｎ−（ｔ−ブチル）アミノエチル等の（メタ）アクリル酸Ｎ−アルキルアミノアルキル；（メタ）アクリル酸Ｎ，Ｎ−ジメチルアミノエチル、（メタ）アクリル酸Ｎ，Ｎ−ジメチルアミノプロピル等の（メタ）アクリル酸Ｎ，Ｎ−ジアルキルアミノアルキルなどが挙げられる。 As the nitrogen atom-containing vinyl monomer, there is no problem as long as it contains a nitrogen atom and can be copolymerized with the above-mentioned (meth) acrylate monomer having 1 to 8 carbon atoms. For example, an amino group-containing monomer and an amide group-containing monomer , Nitrogen-based heterocyclic ring-containing monomer, cyano group-containing monomer, imide group-containing monomer and the like. Examples of these monomers include (meth) amino group-containing monomers such as (meth) aminomethyl acrylate, (meth) aminoethyl acrylate, (meth) aminopropyl acrylate, and (meth) aminoisopropyl acrylate. Examples thereof include aminoalkyl acrylate and (meth) acrylate (N-substituted) aminoalkyl. Examples of the (meth) acrylic acid (N-substituted) aminoalkyl include (meth) acrylic acid N-alkylaminoalkyl such as (meth) acrylic acid N- (t-butyl) aminoethyl; (meth) acrylic acid. Examples thereof include N, N-dialkylaminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl and N, N-dimethylaminopropyl (meth) acrylates.

その中でも、アミノ基含有モノマー、アミド基含有モノマーが好ましい。なかでもアミノ基含有モノマーが特に好ましい。当該窒素含有ビニルモノマーを使用することで、（メタ）アクリル系共重合体（Ａ）と相互作用を形成し、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 Among them, amino group-containing monomers and amide group-containing monomers are preferable. Of these, amino group-containing monomers are particularly preferable. By using the nitrogen-containing vinyl monomer, the conductive pressure-sensitive adhesive layer is imparted with the cohesive force necessary for forming an interaction with the (meth) acrylic copolymer (A) and suppressing peeling over time. can.

アクリル系エステル共重合体（Ｂ）を構成するモノマー成分中の窒素原子含有ビニルモノマーの含有量は、当該共重合体の総量に対し、１〜３０重量％とすることが好ましく、１〜２０質量％にすることがより好ましい。当該範囲の（メタ）アクリル系共重合体（Ｂ）中の上記窒素原子含有ビニルモノマーの含有量にすることで、（メタ）アクリル系共重合体（Ａ）と相互作用を形成し、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 The content of the nitrogen atom-containing vinyl monomer in the monomer components constituting the acrylic ester copolymer (B) is preferably 1 to 30% by mass, preferably 1 to 20% by mass, based on the total amount of the copolymer. It is more preferable to set it to%. By setting the content of the nitrogen atom-containing vinyl monomer in the (meth) acrylic copolymer (B) in the above range, an interaction with the (meth) acrylic copolymer (A) is formed over time. It is possible to impart the cohesive force required for suppressing the peeling of the conductive pressure-sensitive adhesive layer to the conductive pressure-sensitive adhesive layer.

当該窒素原子含有（メタ）（メタ）アクリル系共重合体（Ｂ）の重量平均分子量Ｍｗは５０００〜１０万であるが、６０００〜８万がより好ましく、７０００〜５万がさらに好ましい。当該窒素原子含有（メタ）アクリル酸エステル共重合体（Ｂ）の重量平均分子量Ｍｗが上記範囲内だと、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 The weight average molecular weight Mw of the nitrogen atom-containing (meth) (meth) acrylic copolymer (B) is 5,000 to 100,000, more preferably 6,000 to 80,000, and even more preferably 7,000 to 50,000. When the weight average molecular weight Mw of the nitrogen atom-containing (meth) acrylic acid ester copolymer (B) is within the above range, the cohesive force necessary for suppressing peeling over time can be imparted to the conductive pressure-sensitive adhesive layer. ..

（粘着剤組成物）
本発明の導電性粘着シートの導電性粘着剤層を形成する（メタ）アクリル系粘着剤組成物は、上記カルボキシル基含有（メタ）アクリル系共重合体（Ａ）と、窒素原子含有（メタ）アクリル系共重合体（Ｂ）とを有し、カルボキシル基含有（メタ）アクリル系共重合体（Ａ）１００質量％に対して、窒素原子含有（メタ）アクリル系共重合体（Ｂ）の質量比が５％〜５０％であることが好ましく、質量比が７％〜４０％であることがより好ましく、１０％〜３０％であることが更に好ましい。上記範囲内で共重合体（Ａ）と（Ｂ）とが配合されることで、経時での剥がれを抑制するために必要な凝集力を導電性粘着剤層に付与できる。 (Adhesive composition)
The (meth) acrylic pressure-sensitive adhesive composition forming the conductive pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet of the present invention comprises the above-mentioned carboxyl group-containing (meth) acrylic copolymer (A) and nitrogen atom-containing (meth). It has an acrylic copolymer (B), and the mass of the nitrogen atom-containing (meth) acrylic copolymer (B) with respect to 100% by mass of the carboxyl group-containing (meth) acrylic copolymer (A). The ratio is preferably 5% to 50%, the mass ratio is more preferably 7% to 40%, and even more preferably 10% to 30%. By blending the copolymers (A) and (B) within the above range, it is possible to impart the cohesive force necessary for suppressing peeling over time to the conductive pressure-sensitive adhesive layer.

（添加剤）
導電性粘着シートの粘着力を向上させるため、粘着付与樹脂を添加しても良い。本発明で使用する導電性粘着剤に添加する粘着付与樹脂は、ロジン系樹脂、テルペン系樹脂、脂肪族（Ｃ５系）や芳香族（Ｃ９系）などの石油樹脂、スチレン系樹脂フェノール系樹脂、キシレン系樹脂、メタクリル系樹脂などが挙げられる。そのなかでも、ロジン系樹脂が好ましく、特に重合ロジン系樹脂が好ましい。粘着付与樹脂の添加量としては、（メタ）アクリル系共重合体１００質量部（固形分）に対し、１０〜５０質量部添加するのが好ましい。 (Additive)
In order to improve the adhesive strength of the conductive adhesive sheet, an adhesive resin may be added. The tackifier resin added to the conductive pressure-sensitive adhesive used in the present invention includes rosin-based resin, terpene-based resin, petroleum resin such as aliphatic (C5 series) and aromatic (C9 series), styrene resin phenolic resin, and the like. Examples thereof include xylene-based resins and methacrylic-based resins. Among them, a rosin-based resin is preferable, and a polymerized rosin-based resin is particularly preferable. The amount of the tackifier resin added is preferably 10 to 50 parts by mass with respect to 100 parts by mass (solid content) of the (meth) acrylic copolymer.

本発明の導電性粘着シートに使用する粘着剤には必要に応じて、各種添加剤が添加されても良い。上記添加剤としては、例えば可塑剤、軟化剤、金属不活性剤、酸化防止剤、顔料、染料などが挙げられ、必要に応じて適宜使用される。 Various additives may be added to the pressure-sensitive adhesive used for the conductive pressure-sensitive adhesive sheet of the present invention, if necessary. Examples of the additive include plasticizers, softeners, metal deactivators, antioxidants, pigments, dyes and the like, and are appropriately used as necessary.

（トリアゾール系化合物）
本発明の導電性粘着シートに使用する粘着剤はトリアゾール系化合物を含有する。トリアゾール化合物としては、ベンゾトリアゾール、トリルトリアゾール及びそのカリウム塩、３−（Ｎ−サリチロイル）アミノ−１，２，４トリアゾール、２−（２’−ヒドロキシ５メチルフェニル）ベンゾトリアゾールなどが挙げられる。そのなかでもベンゾトリアゾールが溶解性・接着力低下防止効果が高く好ましい。 (Triazole compound)
The pressure-sensitive adhesive used in the conductive pressure-sensitive adhesive sheet of the present invention contains a triazole-based compound. Examples of the triazole compound include benzotriazole, tolyltriazole and its potassium salt, 3- (N-salicyloyl) amino-1,2,4triazole, 2- (2'-hydroxy-5methylphenyl) benzotriazole and the like. Among them, benzotriazole is preferable because it has a high solubility and an effect of preventing a decrease in adhesive strength.

トリアゾール系化合物の含有量としては、特に限定されるものではないが、アクリル系粘着剤組成物１００質量部（固形分）に対し、０．０５〜３．０質量部が好ましい。そのなかでも０．１〜１．５質量部が好ましく、０．３〜１．０質量部が最も好ましい。当該含有量とすることで、特に好適な保持力を得やすく、また高温高湿環境試験後の接着力低下を特に抑制しやすくなる。 The content of the triazole-based compound is not particularly limited, but is preferably 0.05 to 3.0 parts by mass with respect to 100 parts by mass (solid content) of the acrylic pressure-sensitive adhesive composition. Among them, 0.1 to 1.5 parts by mass is preferable, and 0.3 to 1.0 parts by mass is most preferable. By setting the content to this level, it becomes easy to obtain a particularly suitable holding force, and it becomes particularly easy to suppress a decrease in the adhesive force after the high temperature and high humidity environment test.

（架橋剤）
本発明の導電性粘着シートに使用するアクリル系粘着剤組成物には、架橋剤を含有することで、得られる導電性粘着剤層に３次元架橋構造を形成することで、凝集力を向上させる。架橋構造の形成には、例えば、イソシアネート系架橋剤、エポキシ系架橋剤、キレート系架橋剤、アジリジン系架橋剤など、公知の架橋剤などが挙げられる。架橋剤の種類は、前述の単量体成分の官能基に応じて選定するのが好ましい。 (Crosslinking agent)
The acrylic pressure-sensitive adhesive composition used for the conductive pressure-sensitive adhesive sheet of the present invention contains a cross-linking agent to form a three-dimensional cross-linked structure in the obtained conductive pressure-sensitive adhesive layer, thereby improving the cohesive force. .. Examples of the formation of the cross-linked structure include known cross-linking agents such as isocyanate-based cross-linking agents, epoxy-based cross-linking agents, chelate-based cross-linking agents, and aziridine-based cross-linking agents. The type of the cross-linking agent is preferably selected according to the functional group of the above-mentioned monomer component.

架橋剤の添加量としては、得られる導電性粘着剤層のゲル分率が、２５〜８０質量％となる量で使用することが好ましく、より好ましくは３５〜７０質量％であり、最も好ましくは４０〜６０質量％である。ゲル分率を上記範囲とすることで、せん断方向の凝集力及び耐剥がれ性をより良好にすることができる。 The amount of the cross-linking agent added is preferably such that the gel fraction of the obtained conductive pressure-sensitive adhesive layer is 25 to 80% by mass, more preferably 35 to 70% by mass, and most preferably. It is 40 to 60% by mass. By setting the gel fraction within the above range, the cohesive force and peeling resistance in the shear direction can be further improved.

ゲル分率は、以下の式で算出する。 The gel fraction is calculated by the following formula.

ゲル分率（質量％）＝｛（トルエンに浸漬した後の粘着剤質量）／（トルエンに浸漬する前の粘着剤質量）｝×１００ Gel fraction (% by mass) = {(mass of adhesive after immersion in toluene) / (mass of adhesive before immersion in toluene)} x 100

（導電性粒子）
本発明の導電性粘着シートに使用する導電性粒子の材質としては金、銀、銅、ニッケル、アルミニウム等の金属粉粒子、カーボン、グラファイト等の導電性樹脂、樹脂や中実ガラスビーズ、中空ガラスビーズの表面に金属被覆を有するもの等が使用できる。そのなかでもニッケル粉粒子や銅粉粒子や銀粉粒子が導電性、接着性、生産性に優れるため好ましい。さらに好ましいものとしては、カーボニル法で製造される粒子表面に多数の針状形状を有する表面針状形状のニッケル粒子や、当該表面針状粒子を平滑化処理して球状粒子としたものや、超高圧旋回水アトマイズ法で製造される銅粉や銀粉があげられる。これらの導電性粒子は２種類以上混合して使用してもよい。 (Conductive particles)
The material of the conductive particles used in the conductive pressure-sensitive adhesive sheet of the present invention is metal powder particles such as gold, silver, copper, nickel and aluminum, conductive resins such as carbon and graphite, resins and solid glass beads, and hollow glass. Those having a metal coating on the surface of the beads can be used. Among them, nickel powder particles, copper powder particles and silver powder particles are preferable because they are excellent in conductivity, adhesiveness and productivity. More preferred are surface needle-shaped nickel particles having a large number of needle-shaped particles on the surface of the particles produced by the carbonyl method, smoothed surface needle-shaped particles to form spherical particles, and super. Examples include copper powder and silver powder produced by the high-pressure swirling water atomizing method. Two or more kinds of these conductive particles may be mixed and used.

導電性粒子の形状としては球状、表面針状形状、又は図３で示すような多数の導電性粒子間で結合等を形成し連なった数珠状などが上げられるが、中でも数珠状が好ましい。 Examples of the shape of the conductive particles include a spherical shape, a surface needle-like shape, and a bead shape in which a bond or the like is formed between a large number of conductive particles as shown in FIG. 3 and connected to each other. Among them, the bead shape is preferable.

導電性粒子の粒子径としては、特に限定されるものではないが、粒子径ｄ５０が５〜３０μｍであり、且つ粒子径ｄ９０が２５〜６０μｍであることが好ましい。ｄ５０は、より好ましくは１０〜２５μｍであり、さらに好ましくは１２〜２０μｍであり、１３〜１８μｍであることが最も好ましい。またｄ９０は、より好ましくは２７〜５５μｍであり、さらに好ましくは３０〜５０μｍであり、３１〜５０μｍであることが最も好ましい。なお、導電性粒子を２種以上混合する場合には、混合後の粒子径ｄ５０及びｄ９０が上記範囲であることが好ましい。 The particle size of the conductive particles is not particularly limited, but it is preferable that the particle size d50 is 5 to 30 μm and the particle size d90 is 25 to 60 μm. The d50 is more preferably 10 to 25 μm, still more preferably 12 to 20 μm, and most preferably 13 to 18 μm. Further, d90 is more preferably 27 to 55 μm, further preferably 30 to 50 μm, and most preferably 31 to 50 μm. When two or more kinds of conductive particles are mixed, it is preferable that the mixed particle diameters d50 and d90 are in the above range.

前記粒子径ｄ５０は粒度分布における５０％累積値を指し、前記粒子径ｄ９０は粒度分布における９０％累積値を指し、レーザー解析・散乱法により測定される値である。測定装置としては日機装社製マイクロトラックＭＴ３０００II、島津製作所製レーザー回折式粒度分布測定器ＳＡＬＤ−３０００等があげられる。 The particle size d50 refers to a 50% cumulative value in the particle size distribution, and the particle size d90 refers to a 90% cumulative value in the particle size distribution, which is a value measured by a laser analysis / scattering method. Examples of the measuring device include a Microtrack MT3000II manufactured by Nikkiso Co., Ltd., a laser diffraction type particle size distribution measuring device SALD-3000 manufactured by Shimadzu Co., Ltd., and the like.

前記範囲の粒子径ｄ５０に調整する方法としては、例えば導電性粒子をジェットミルで粉砕する方法や篩等による篩分け法が挙げられる。 Examples of the method for adjusting the particle size to the particle size d50 in the above range include a method of pulverizing conductive particles with a jet mill and a sieving method using a sieve or the like.

導電性粒子の粒子径ｄ５０が粘着剤層厚さの５０〜１５０％であり、ｄ９０が１００〜３００％であることが好ましい。上記範囲の導電性粒子を用いることで、導電性・接着性・生産性を両立しやすい。ｄ５０はさらに好ましくは６０〜１２０％であり、最も好ましくは７０〜１００％である。ｄ９０はさらに好ましくは１２０〜２５０％であり、もっと好ましくは１５０〜２００％である。 The particle size d50 of the conductive particles is preferably 50 to 150% of the thickness of the pressure-sensitive adhesive layer, and d90 is preferably 100 to 300%. By using conductive particles in the above range, it is easy to achieve both conductivity, adhesiveness, and productivity. d50 is more preferably 60 to 120%, most preferably 70 to 100%. d90 is more preferably 120 to 250%, more preferably 150 to 200%.

導電性粘着剤層中の導電性粒子の含有量としては、特に限定されるものではないが、アクリル系粘着剤組成物１００質量部（固形分）に対して、１０〜１００質量部が好ましく、さらに好ましくは２０〜８０質量部であり、より好ましくは３０〜７０質量部であり、４０〜６０質量部が最も好ましい。導電性粒子の含有量を上記範囲にすることで、導電性、接着性、生産性を両立しやすくなる。 The content of the conductive particles in the conductive pressure-sensitive adhesive layer is not particularly limited, but is preferably 10 to 100 parts by mass with respect to 100 parts by mass (solid content) of the acrylic pressure-sensitive adhesive composition. It is more preferably 20 to 80 parts by mass, more preferably 30 to 70 parts by mass, and most preferably 40 to 60 parts by mass. By setting the content of the conductive particles in the above range, it becomes easy to achieve both conductivity, adhesiveness, and productivity.

アクリル系粘着剤組成物中に前記導電性粒子を分散する方法としては、（メタ）アクリル系共重合体、溶剤、導電性粒子、添加剤等を分散攪拌機で分散する方法が挙げられる。市販の分散攪拌機としては、井上製作所製ディゾルバー、バタフライミキサー、ＢＤＭ２軸ミキサー、プラネタリーミキサーが挙げられる。そのなかでも撹拌中の粘着剤の増粘が少ない中程度のシェアをかけられるディゾルバーやバタフライミキサーが好ましい。 Examples of the method of dispersing the conductive particles in the acrylic pressure-sensitive adhesive composition include a method of dispersing a (meth) acrylic copolymer, a solvent, conductive particles, additives and the like with a dispersion stirrer. Examples of the commercially available dispersion stirrer include a dissolver manufactured by Inoue Seisakusho, a butterfly mixer, a BDM 2-axis mixer, and a planetary mixer. Among them, a dissolver and a butterfly mixer that can apply a medium share with less thickening of the adhesive during stirring are preferable.

アクリル系粘着剤組成物の固形分としては、特に限定されるものではないが、１０〜７０％が好ましく、さらに好ましくは３０〜５５％、最も好ましくは４３〜５０％である。 The solid content of the acrylic pressure-sensitive adhesive composition is not particularly limited, but is preferably 10 to 70%, more preferably 30 to 55%, and most preferably 43 to 50%.

（導電性粘着剤層）
導電性粘着シートの粘着剤層の厚さは、３０μｍ以下である。好ましくは５〜２５μｍであり、中でも、１０〜２０μｍであることが特に好ましい。上記範囲にある場合に、接着性と薄型を両立できる。 (Conductive adhesive layer)
The thickness of the pressure-sensitive adhesive layer of the conductive pressure-sensitive adhesive sheet is 30 μm or less. It is preferably 5 to 25 μm, and particularly preferably 10 to 20 μm. When it is within the above range, both adhesiveness and thinness can be achieved.

導電性粘着シートの粘着剤層を１０％変形させたときの引張強度は、３．０〜６．０Ｎ／ｃｍ^２であることが好ましく、３．５〜５．５Ｎ／ｃｍ^２であることが更に好ましく、４．０〜５．０Ｎ／ｃｍ^２であることがより好ましい。上記範囲にある場合に、経時での剥がれを抑制でき、経時での抵抗値上昇を抑制しやすくなる。 Tensile strength when the adhesive layer is deformed by 10% of the conductive adhesive sheet, it is preferably 3.0~6.0N / cm ^2, a 3.5~5.5N / cm ² More preferably, it is more preferably 4.0 to 5.0 N / cm ^2. When it is within the above range, peeling over time can be suppressed, and it becomes easy to suppress an increase in resistance value over time.

（導電性基材）
本発明の導電性粘着シートに使用する導電性基材としては、金属箔基材や湿式のポリエステル系不織布基材にメッキが施された導電性基材等があげられる。金属箔の材質としては、金、銀、銅、アルミニウム、ニッケル、鉄、錫やこれらの合金が挙げられる。そのなかでも銅を含有する導電性基材が好ましく、銅箔が導電性、加工性、コストの点からより好ましい。 (Conductive base material)
Examples of the conductive base material used for the conductive pressure-sensitive adhesive sheet of the present invention include a metal foil base material and a conductive base material obtained by plating a wet polyester-based non-woven fabric base material. Examples of the material of the metal foil include gold, silver, copper, aluminum, nickel, iron, tin and alloys thereof. Among them, a conductive base material containing copper is preferable, and copper foil is more preferable in terms of conductivity, processability, and cost.

さらに銅箔には防錆処理を施すことが好ましい。防錆処理の種類としては、有機防錆と無機防錆が挙げられるが、そのなかでも、クロメート処理による無機防錆が最も好ましい。市販の電解銅箔としては、福田金属箔粉工業社製ＣＦ−Ｔ９ＦＺ−ＨＳ−１２（１２μｍ：クロメート処理）やＣＦ−Ｔ９ＦＺ−ＨＳ−９（９μｍ：クロメート処理）等が挙げられる。市販の圧延銅箔としては、日本製箔社製ＴＣＵ−Ｈ−８−ＲＴ（８μｍ：有機防錆処理）やＪＸ日鉱日石金属社製ＢＡＹ−６４Ｔ−ＤＴ（３５μｍ：クロメート処理）等が挙げられる。 Further, it is preferable to apply a rust preventive treatment to the copper foil. Examples of the type of rust preventive treatment include organic rust preventive and inorganic rust preventive, and among them, inorganic rust preventive by chromate treatment is most preferable. Examples of commercially available electrolytic copper foils include CF-T9FZ-HS-12 (12 μm: chromate treatment) and CF-T9FZ-HS-9 (9 μm: chromate treatment) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd. Examples of commercially available rolled copper foil include TCU-H-8-RT (8 μm: organic rust preventive treatment) manufactured by Nippon Foil Corporation and BAY-64T-DT (35 μm: chromate treatment) manufactured by JX Nippon Mining & Metals Co., Ltd. Be done.

上記湿式のポリエステル系不織布基材にメッキが施された導電性基材としては、当該メッキとして無電解金属メッキを使用したものである。メッキする金属としては、銅、ニッケル、銀、白金、アルミニウムが挙げられるが、そのなかでも、導電性やコストの点から銅又はニッケルが好ましい。 As the conductive base material obtained by plating the wet polyester-based non-woven fabric base material, electroless metal plating is used as the plating. Examples of the metal to be plated include copper, nickel, silver, platinum, and aluminum, and among them, copper or nickel is preferable from the viewpoint of conductivity and cost.

導電性基材の厚みとしては、１〜４０μｍが好ましく、さらに好ましくは３〜３５μｍであり、最も好ましくは６〜２５μｍである。上記範囲であれば、薄型化が可能で、且つ加工性に優れるため好ましい。 The thickness of the conductive substrate is preferably 1 to 40 μm, more preferably 3 to 35 μm, and most preferably 6 to 25 μm. Within the above range, it is preferable because it can be made thinner and has excellent workability.

（剥離ライナー）
本発明の導電性粘着シートでは、粘着剤層上に剥離ライナーを積層することができる。剥離ライナーは、特に限定されず、例えばクラフト紙やグラシン紙、上質紙などの紙類や、ポリエチレン、ポリプロピレン（ＯＰＰ、ＣＰＰ）、ポリエチレンテレフタレートなどの樹脂フィルム、前記紙類と樹脂フィルムを積層したラミネート紙、前記紙類にクレーやポリビニルアルコールなどで目止め処理を施したものの片面もしくは両面に、シリコン系樹脂等の剥離処理を施したものなど従来公知のものを用いることができる。 (Peeling liner)
In the conductive pressure-sensitive adhesive sheet of the present invention, a release liner can be laminated on the pressure-sensitive adhesive layer. The release liner is not particularly limited, for example, papers such as kraft paper, glassin paper, and high-quality paper, resin films such as polyethylene, polypropylene (OPP, CPP), and polyethylene terephthalate, and laminates obtained by laminating the papers and resin films. Conventionally known papers, such as those obtained by sealing the papers with clay or polyvinyl alcohol and having a peeling treatment of a silicon-based resin or the like on one or both sides of the paper, can be used.

（導電性粘着シート）
本発明の導電性粘着シートは、上記導電性粘着剤層と導電性基材とを有する導電性粘着シートである。 (Conductive adhesive sheet)
The conductive pressure-sensitive adhesive sheet of the present invention is a conductive pressure-sensitive adhesive sheet having the above-mentioned conductive pressure-sensitive adhesive layer and a conductive base material.

本発明の導電性粘着シートの温度２３℃、相対湿度５０％ＲＨの環境下で、ＳＵＳに対し、２ｋｇローラーを使用して圧着回数一往復で圧着し、１時間静置した後の３００ｍｍ／ｍｉｎでの１８０°剥離接着力は、ＳＵＳに対してそれぞれ５〜１５Ｎ／２０ｍｍであることが好ましい。上記範囲内だと、剥がれを抑制しやすく、また、製造工程での貼り合わせ不良品において導電性粘着シートの剥離が可能となる。 In an environment where the temperature of the conductive adhesive sheet of the present invention is 23 ° C. and the relative humidity is 50% RH, the conductive adhesive sheet is crimped against SUS in one reciprocating crimping frequency using a 2 kg roller, and then allowed to stand for 1 hour at 300 mm /. The 180 ° peeling adhesive force in min is preferably 5 to 15 N / 20 mm with respect to SUS, respectively. Within the above range, peeling can be easily suppressed, and the conductive adhesive sheet can be peeled off in a poorly bonded product in the manufacturing process.

本発明の導電性粘着シートの総厚みは好ましくは、８５μｍ以下であり、さらに好ましくは６５μｍ以下であり、５０μｍ以下であることが特に好ましい。上記範囲にあることで、接着性・導電性を確保しつつ、粘着シートの薄型化を図ることができ、携帯電子機器の薄型化に貢献できる。なお、導電性粘着シートの総厚みとは、剥離ライナーを含まない導電性粘着シート自体の厚みである。 The total thickness of the conductive pressure-sensitive adhesive sheet of the present invention is preferably 85 μm or less, more preferably 65 μm or less, and particularly preferably 50 μm or less. Within the above range, the adhesive sheet can be made thinner while ensuring adhesiveness and conductivity, which can contribute to making the portable electronic device thinner. The total thickness of the conductive pressure-sensitive adhesive sheet is the thickness of the conductive pressure-sensitive adhesive sheet itself that does not include the release liner.

本発明の導電性粘着シートは、一般的に使用されている方法で作成できる。具体的には、離型ライナー上に塗布し、乾燥または硬化し、導電性粘着剤層を形成後、導電性基材に貼り合わせる方法などにより製造できる。 The conductive pressure-sensitive adhesive sheet of the present invention can be prepared by a commonly used method. Specifically, it can be manufactured by a method of applying it on a release liner, drying or curing it to form a conductive pressure-sensitive adhesive layer, and then attaching it to a conductive substrate.

離型ライナー上に形成した導電性粘着剤層と導電性基材を貼り合せる際には、熱ラミネートをすることが、導電性基材と導電性粘着剤層との優れた密着性を付与する観点で好ましい。熱ラミネートの温度は６０℃〜１５０℃が好ましく、７０℃〜１３０℃がより好ましく、８０℃〜１１０℃が密着性と導電性基材の収縮を抑制するうえで更に好ましい。 When the conductive pressure-sensitive adhesive layer formed on the release liner and the conductive base material are bonded together, thermal laminating imparts excellent adhesion between the conductive base material and the conductive pressure-sensitive adhesive layer. Preferred from the viewpoint. The temperature of the thermal laminating is preferably 60 ° C. to 150 ° C., more preferably 70 ° C. to 130 ° C., and even more preferably 80 ° C. to 110 ° C. in order to suppress adhesion and shrinkage of the conductive substrate.

本発明の導電性粘着シートの好適な構成の例を図１及び図２に示す。図１は、導電性基材１上に導電性粘着剤層２を積層した片面粘着シートである。また、図２は、導電性基材１の両面に導電性粘着剤層２を積層した両面粘着シートである。これら構成においては、粘着剤層２の表面に、剥離ライナーが設けられた構成を好ましく使用できる。 1 and 2 show examples of suitable configurations of the conductive pressure-sensitive adhesive sheet of the present invention. FIG. 1 is a single-sided pressure-sensitive adhesive sheet in which a conductive pressure-sensitive adhesive layer 2 is laminated on a conductive base material 1. Further, FIG. 2 is a double-sided pressure-sensitive adhesive sheet in which the conductive pressure-sensitive adhesive layer 2 is laminated on both sides of the conductive base material 1. In these configurations, a configuration in which a release liner is provided on the surface of the pressure-sensitive adhesive layer 2 can be preferably used.

以下に実施例について具体的に説明するが、本発明はこれらの実施例に限定されるものではない。 Examples will be specifically described below, but the present invention is not limited to these examples.

［アクリル共重合体の調製］
＜アクリル共重合体（１）＞
アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、ｎ−ブチルアクリレート９１．５質量部、２−ヒドロキシエチルアクリレート０．５質量部、アクリル酸８．０質量部と重合開始剤として２，２’−アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量部に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量８０万のアクリル共重合体（１）を得た。 [Preparation of acrylic copolymer]
<Acrylic copolymer (1)>
Preparation of acrylic polymer In a reaction vessel equipped with a stirrer, a cold current cooler, a thermometer, a dropping funnel and a nitrogen gas inlet, 91.5 parts by mass of n-butyl acrylate, 0.5 part by mass of 2-hydroxyethyl acrylate, 8.0 parts by mass of acrylic acid and 0.2 parts of 2,2'-azobisisobutylnitrile as a polymerization initiator are dissolved in 100 parts by mass of ethyl acetate, polymerized at 80 ° C. for 8 hours after substitution with nitrogen, and weight averaged. An acrylic copolymer (1) having a molecular weight of 800,000 was obtained.

＜アクリル共重合体（２）＞
ｎ−ブチルアクリレートを９５．５質量部、アクリル酸を４．０質量部とする以外は、アクリル酸共重合体（１）と同様にして、重量平均分子量８０万のアクリル共重合体（２）を得た。 <Acrylic copolymer (2)>
Acrylic copolymer (2) having a weight average molecular weight of 800,000 in the same manner as the acrylic acid copolymer (1) except that n-butyl acrylate is 95.5 parts by mass and acrylic acid is 4.0 parts by mass. Got

＜アクリル共重合体（３）＞
２，２’−アゾビスイソブチルニトリル０．１部とする以外は、アクリル酸共重合体（１）と同様にして、重量平均分子量１５０万のアクリル共重合体（３）を得た。 <Acrylic copolymer (3)>
An acrylic copolymer (3) having a weight average molecular weight of 1.5 million was obtained in the same manner as the acrylic acid copolymer (1) except that the amount was 2,2'-azobisisobutylnitrile (0.1 part).

＜アクリル共重合体（４）＞
２，２’−アゾビスイソブチルニトリル０．５部とする以外は、アクリル酸共重合体（１）と同様にして、重量平均分子量３０万のアクリル共重合体（３）を得た。 <Acrylic copolymer (4)>
An acrylic copolymer (3) having a weight average molecular weight of 300,000 was obtained in the same manner as the acrylic acid copolymer (1) except that the amount was 2,2'-azobisisobutylnitrile (0.5 part).

＜アクリル共重合体（５）＞
アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、メチルメタクリレート９５．０質量部、ジメチルアミノエチルメタクリレート５．０質量部と重合開始剤として２，２’−アゾビスイソブチルニトリル１．０質量部とを酢酸エチル１００質量部に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量２万のメタクリル共重合体（５）を得た。 <Acrylic copolymer (5)>
Preparation of Acrylic Copolymer In a reaction vessel equipped with a stirrer, a cold current cooler, a thermometer, a dropping funnel and a nitrogen gas inlet, 95.0 parts by mass of methyl methacrylate, 5.0 parts by mass of dimethylaminoethyl methacrylate and a polymerization initiator. As a result, 1.0 part by mass of 2,2'-azobisisobutylnitrile was dissolved in 100 parts by mass of ethyl acetate, and after substitution with nitrogen, the polymer was polymerized at 80 ° C. for 8 hours to obtain a methacrylic copolymer having a weight average molecular weight of 20,000 (5). ) Was obtained.

＜アクリル共重合体（６）＞
２，２’−アゾビスイソブチルニトリル０．６部とする以外は、アクリル酸共重合体（５）と同様にして、重量平均分子量６万のアクリル共重合体（６）を得た。 <Acrylic copolymer (6)>
An acrylic copolymer (6) having a weight average molecular weight of 60,000 was obtained in the same manner as the acrylic acid copolymer (5) except that the amount was 2,2'-azobisisobutylnitrile (0.6 part).

＜粘着剤Ａ＞
上記アクリル共重合体（１）１００質量部に、上記アクリル共重合体（５）を２０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ａを得た。 <Adhesive A>
To 100 parts by mass of the acrylic copolymer (1), 20 parts by mass of the acrylic copolymer (5) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive A having a resin solid content of 25%.

＜粘着剤Ｂ＞
上記アクリル共重合体（１）１００質量部に、上記アクリル共重合体（５）を１０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｂを得た。 <Adhesive B>
To 100 parts by mass of the acrylic copolymer (1), 10 parts by mass of the acrylic copolymer (5) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive B having a resin solid content of 25%.

＜粘着剤Ｃ＞
上記アクリル共重合体（２）１００質量部に、上記アクリル共重合体（５）を２０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｃを得た。 <Adhesive C>
To 100 parts by mass of the acrylic copolymer (2), 20 parts by mass of the acrylic copolymer (5) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive C having a resin solid content of 25%.

＜粘着剤Ｄ＞
上記アクリル共重合体（３）１００質量部に、上記アクリル共重合体（５）を２０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｄを得た。 <Adhesive D>
To 100 parts by mass of the acrylic copolymer (3), 20 parts by mass of the acrylic copolymer (5) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive D having a resin solid content of 25%.

＜粘着剤Ｅ＞
上記アクリル共重合体（１）１００質量部に、上記アクリル共重合体（６）を２０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｅを得た。 <Adhesive E>
To 100 parts by mass of the acrylic copolymer (1), 20 parts by mass of the acrylic copolymer (6) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive E having a resin solid content of 25%.

＜粘着剤Ｆ＞
上記アクリル共重合体（４）１００質量部に、上記アクリル共重合体（５）を２０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｆを得た。 <Adhesive F>
To 100 parts by mass of the acrylic copolymer (4), 20 parts by mass of the acrylic copolymer (5) was added and diluted with ethyl acetate to obtain a pressure-sensitive adhesive F having a resin solid content of 25%.

＜粘着剤Ｇ＞
上記アクリル共重合体（１）１００質量部に、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｆを得た。 <Adhesive G>
100 parts by mass of the acrylic copolymer (1) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive F having a resin solid content of 25%.

＜粘着剤Ｈ＞
上記アクリル共重合体（１）１００質量部に、上記アクリル共重合体（５）を６０質量部添加し、酢酸エチルで希釈し樹脂固形分２５％の粘着剤Ｈを得た。 <Adhesive H>
60 parts by mass of the acrylic copolymer (5) was added to 100 parts by mass of the acrylic copolymer (1) and diluted with ethyl acetate to obtain a pressure-sensitive adhesive H having a resin solid content of 25%.

（導電性粘着剤組成物の作成）
［導電性粘着剤組成物（１Ａ）の作成］
前記粘着剤（Ａ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ａを作成した。 (Preparation of Conductive Adhesive Composition)
[Preparation of Conductive Adhesive Composition (1A)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (A). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1A.

［導電性粘着剤組成物（２Ａ）の作成］
前記粘着剤（Ａ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．６３質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤２Ａを作成した。 [Preparation of Conductive Adhesive Composition (2A)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (A). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.63 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 2A.

［導電性粘着剤組成物（３Ａ）の作成］
前記粘着剤（Ａ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）５．７質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．６３質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤３Ａを作成した。 [Preparation of Conductive Adhesive Composition (3A)]
5.7 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (A). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.63 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 3A.

［導電性粘着剤組成物（４Ａ）の作成］
前記粘着剤（Ａ）１００質量部（固形分２５質量部）に対して、日興リカ社製ニッケル粉ＮＩ５２５（ｄ５０：１４．３μｍ、ｄ９０：４０．５μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．６３質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤４Ａを作成した。 [Preparation of Conductive Adhesive Composition (4A)]
11.3 parts by mass of nickel powder NI525 (d50: 14.3 μm, d90: 40.5 μm) manufactured by Nikko Rika Co., Ltd. with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (A), cross-linking agent E-. 2XM (epoxy-based cross-linking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.63 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate and dispersed. The conductive pressure-sensitive adhesive 4A was prepared by mixing with a stirrer for 10 minutes.

［導電性粘着剤組成物（１Ｂ）の作成］
前記粘着剤（Ｂ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｂを作成した。 [Preparation of Conductive Adhesive Composition (1B)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (B). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1B.

［導電性粘着剤組成物（１Ｃ）の作成］
前記粘着剤（Ｃ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｃを作成した。 [Preparation of Conductive Adhesive Composition (1C)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (C). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1C.

［導電性粘着剤組成物（１Ｄ）の作成］
前記粘着剤（Ｄ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｄを作成した。 [Preparation of Conductive Adhesive Composition (1D)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (D). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1D.

［導電性粘着剤組成物（１Ｅ）の作成］
前記粘着剤（Ｅ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｅを作成した。 [Preparation of Conductive Adhesive Composition (1E)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (E). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1E.

［導電性粘着剤組成物（１Ｆ）の作成］
前記粘着剤（Ｆ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｆを作成した。 [Preparation of Conductive Adhesive Composition (1F)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (F). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1F.

［導電性粘着剤組成物（１Ｇ）の作成］
前記粘着剤（Ｇ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤１Ｆを作成した。 [Preparation of Conductive Adhesive Composition (1G)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (G). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive 1F.

［導電性粘着剤組成物（１Ｈ）の作成］
前記粘着剤（Ｈ）１００質量部（固形分２５質量部）に対して、福田金属箔粉工業社製ニッケル粉ＮＩ２５５Ｔ（ｄ５０：１６．２μｍ、ｄ９０：５１．２μｍ）１１．３質量部、架橋剤Ｅ―２ＸＭ（綜研化学社製のエポキシ系架橋剤、固形分２質量％）０．１６質量部、ベンゾトリアゾール０．２３質量部を配合し、酢酸エチルで固形分濃度を２５質量％に調整し、分散攪拌機で１０分混合して導電性粘着剤（１Ｈ）を作成した。 [Preparation of Conductive Adhesive Composition (1H)]
11.3 parts by mass of nickel powder NI255T (d50: 16.2 μm, d90: 51.2 μm) manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., cross-linked with respect to 100 parts by mass (solid content 25 parts by mass) of the pressure-sensitive adhesive (H). Agent E-2XM (epoxy crosslinking agent manufactured by Soken Kagaku Co., Ltd., solid content 2% by mass) 0.16 part by mass and benzotriazole 0.23 part by mass were blended, and the solid content concentration was adjusted to 25% by mass with ethyl acetate. Then, the mixture was mixed with a dispersion stirrer for 10 minutes to prepare a conductive pressure-sensitive adhesive (1H).

（メッキ不織布の作成）
［メッキ不織布Ａ］
三木特種製紙製湿式ポリエステル不織布「タイプＡ」（坪量１０ｇ／ｍ^２、厚み１５μｍ、ポリエステル繊維の直径５μｍ（平均径））を、塩化第一錫１０ｇ／Ｌ、塩酸２０ｍＬ／Ｌを含んだ水溶液に常温で約５分間浸漬し、その後、水洗いした。次に塩化パラジウム１ｇ／Ｌ、塩酸２０ｍＬ／Ｌを含む水溶液に常温で約１０分浸漬し、その後、水洗いした。次に、硫酸銅１０ｇ／Ｌ、ホルムアルデヒド７ｍＬ／Ｌ、水酸化ナトリウム８ｇ／Ｌ、エチレンジアミン４酢酸４ナトリウム（ＥＤＴＡ−４Ｎａ）３０ｇ／Ｌ、安定剤（０．２５ｍＬ／Ｌ）を含む水溶液に４０℃で２０分浸漬し、その後、水洗いした。その後、電気銅メッキ液（奥野製薬工業製、トップルチナＳＦ）を用いて、銅のメッキ量を６ｇ／ｍ^２となるようメッキした。さらに、硫酸ニッケル２４０ｇ／Ｌ、塩化ニッケル４５ｇ／Ｌ、ホウ酸３０ｇ／Ｌ、サッカリン２ｇ／Ｌ、１，４−ブチンジオール０．２ｇ／Ｌを含む電気ニッケルメッキ液中でニッケルメッキ量が４ｇ／ｍ^２になるようメッキし、水洗し、さらに乾燥させ、メッキ不織布Ａを作成した。 (Creation of plated non-woven fabric)
[Plated non-woven fabric A]
An aqueous solution containing Miki Tokushu Paper's wet polyester non-woven fabric "Type A" (basis weight 10 g / m ² , thickness 15 μm, polyester fiber diameter 5 μm (average diameter)), stannous chloride 10 g / L, and hydrochloric acid 20 mL / L. Was immersed in water for about 5 minutes at room temperature, and then washed with water. Next, it was immersed in an aqueous solution containing 1 g / L of palladium chloride and 20 mL / L of hydrochloric acid at room temperature for about 10 minutes, and then washed with water. Next, 40 ° C. in an aqueous solution containing 10 g / L of copper sulfate, 7 mL / L of formaldehyde, 8 g / L of sodium hydroxide, 30 g / L of ethylenediaminetetraacetic acid 4 sodium (EDTA-4Na), and a stabilizer (0.25 mL / L). Soaked in water for 20 minutes and then washed with water. Then, using an electrolytic copper plating solution (manufactured by Okuno Pharmaceutical Co., Ltd., Top Lucina SF), the copper was plated to a plating amount of 6 g / m ² . Further, the nickel plating amount is 4 g / L in an electric nickel plating solution containing 240 g / L of nickel sulfate, 45 g / L of nickel chloride, 30 g / L of boric acid, 2 g / L of saccharin, and 0.2 g / L of 1,4-butindiol. plated so as to be m ^2, washed with water, dried further to prepare a plating nonwoven a.

（実施例１）
［導電性粘着シートの作成］
導電性粘着剤組成物（１Ａ）をニッパ社製剥離フィルム「ＰＥＴ３８×１Ａ３」上に乾燥後の粘着剤層の厚さが１８μｍになるようにコンマコーターで塗工し、８０℃の乾燥器中で２分間乾燥させた後、厚さ１２μｍの無機防錆（クロメート）処理した電解銅箔（ＣＦ−Ｔ９ＦＺ−ＨＳ−１２、福田金属箔粉工業社製）の片面に８０℃で熱ラミネートしたのち、４０℃で４８時間養生して、実施例１の導電性粘着シートを作成した。 (Example 1)
[Creation of conductive adhesive sheet]
The conductive pressure-sensitive adhesive composition (1A) is coated on a release film "PET 38 x 1 A3" manufactured by Nipper Co., Ltd. with a comma coater so that the thickness of the pressure-sensitive adhesive layer after drying is 18 μm, and a dryer at 80 ° C. After drying in the medium for 2 minutes, it was heat-laminated at 80 ° C. on one side of a 12 μm-thick inorganic rust-preventive (chromate) treated electrolytic copper foil (CF-T9FZ-HS-12, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.). Then, it was cured at 40 degreeC for 48 hours to prepare the conductive pressure-sensitive adhesive sheet of Example 1.

（実施例２）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（２Ａ）を用いた以外は実施例１と同様に実施例２の導電性粘着シートを作成した。 (Example 2)
A conductive pressure-sensitive adhesive sheet of Example 2 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (2A) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例３）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（３Ａ）を用いた以外は実施例１と同様に実施例３の導電性粘着シートを作成した。 (Example 3)
A conductive pressure-sensitive adhesive sheet of Example 3 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (3A) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例４）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（４Ａ）を用いた以外は実施例１と同様に実施例４の導電性粘着シートを作成した。 (Example 4)
The conductive pressure-sensitive adhesive sheet of Example 4 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (4A) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例５）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｂ）を用いた以外は実施例１と同様に実施例５の導電性粘着シートを作成した。 (Example 5)
A conductive pressure-sensitive adhesive sheet of Example 5 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1B) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例６）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｃ）を用いた以外は実施例１と同様に実施例６の導電性粘着シートを作成した。 (Example 6)
A conductive pressure-sensitive adhesive sheet of Example 6 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1C) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例７）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｄ）を用いた以外は実施例１と同様に実施例７の導電性粘着シートを作成した。 (Example 7)
The conductive pressure-sensitive adhesive sheet of Example 7 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1D) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例８）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｅ）を用いた以外は実施例１と同様に実施例８の導電性粘着シートを作成した。 (Example 8)
The conductive pressure-sensitive adhesive sheet of Example 8 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1E) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（実施例９）
無機防錆（クロメート）処理した電解銅箔の代わりに、メッキ不織布Ａを用いた以外は実施例１と同様に実施例９の導電性粘着シートを作成した。 (Example 9)
The conductive pressure-sensitive adhesive sheet of Example 9 was prepared in the same manner as in Example 1 except that the plated non-woven fabric A was used instead of the electrolytic copper foil treated with inorganic rust prevention (chromate).

（比較例１）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｆ）を用いた以外は実施例１と同様に比較例１の導電性粘着シートを作成した。 (Comparative Example 1)
A conductive pressure-sensitive adhesive sheet of Comparative Example 1 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1F) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（比較例２）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１G）を用いた以外は実施例１と同様に比較例２の導電性粘着シートを作成した。 (Comparative Example 2)
A conductive pressure-sensitive adhesive sheet of Comparative Example 2 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1G) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（比較例３）
導電性粘着剤組成物（１Ａ）の代わりに、導電性粘着剤組成物（１Ｈ）を用いた以外は実施例１と同様に比較例３の導電性粘着シートを作成した。 (Comparative Example 3)
A conductive pressure-sensitive adhesive sheet of Comparative Example 3 was prepared in the same manner as in Example 1 except that the conductive pressure-sensitive adhesive composition (1H) was used instead of the conductive pressure-sensitive adhesive composition (1A).

（評価）
実施例１〜９、比較例１〜３で作成した導電性粘着シートについて、以下の評価を行い、得られた結果を下表に示した。 (evaluation)
The conductive pressure-sensitive adhesive sheets prepared in Examples 1 to 9 and Comparative Examples 1 to 3 were evaluated as follows, and the obtained results are shown in the table below.

［導電性評価］
図４のように５０ｍｍ幅×５０ｍｍ幅のスズメッキ処理がされた粘着剤層付き銅箔の粘着面を段差１ｍｍの有するガラスパネルの２面に貼り合せ、段差１ｍｍを有する導電性評価用治具を作成した。５ｍｍ幅×１３ｍｍ幅に切断した粘着シートの粘着面を上記で作成した治具の２面に５ｍｍ幅×５ｍｍ幅で貼り合せた後、１００ｇ／ｃｍ^２荷重で３秒間加圧した。２３℃５０％ＲＨの環境下で、３００時間放置した後、低抵抗抵抗率計（三菱ケミカルアナリテック社製ロレスタ―‐ＧＰ）にて１０μＡの電流を流した際の抵抗値を測定した。 [Evaluation of conductivity]
As shown in FIG. 4, the adhesive surfaces of the tin-plated copper foil having an adhesive layer having a width of 50 mm × 50 mm are bonded to two surfaces of a glass panel having a step of 1 mm, and a jig for conducting conductivity evaluation having a step of 1 mm is used. Created. After bonding with 5mm width × 5mm width adhesive surface of the adhesive sheet was cut into 5mm width × 13 mm width dihedral jig created above, it was pressurized three seconds pressurized with 100 g / cm ² load. After leaving it for 300 hours in an environment of 23 ° C. and 50% RH, the resistance value when a current of 10 μA was passed was measured with a low resistivity meter (Lorester-GP manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

◎：３００ｍΩ未満
○：３００ｍΩ〜５００ｍΩ未満
×：５００ｍΩ以上 ⊚: less than 300 mΩ ○: 300 mΩ to less than 500 mΩ ×: 500 mΩ or more

［接着力］
３６０番の耐水研磨紙でヘアライン研磨処理したステンレス板（以下ステンレス板）に、２５ｍｍ幅の導電性粘着シート試料を、２３℃５０％ＲＨの環境下で２．０ｋｇローラ１往復加圧貼付し、常温で１時間放置後、引っ張り試験機（テンシロンＲＴＡ−１００、エーアンドディー社製）にて、常温で引張速度３００ｍｍ／ｍｉｎで１８０度剥離接着力を測定した。 [Adhesive strength]
A 25 mm wide conductive adhesive sheet sample was pressure-bonded to a stainless steel plate (hereinafter referred to as "stainless steel plate") that had been hairline-polished with No. 360 water-resistant abrasive paper under a 2.0 kg roller reciprocating pressure at 23 ° C and 50% RH. After leaving it at room temperature for 1 hour, the peeling adhesive strength was measured at a tensile tester (Tencilon RTA-100, manufactured by A & D Co., Ltd.) at a tensile speed of 300 mm / min at 180 degrees.

［リワーク性］
接着力を測定した際に、メッキの密着性不良や粘着剤の密着性不良によるステンレス板への糊残りを評価した。
○：糊残りなし。
×：１０％以上の糊残りあり。 [Reworkability]
When the adhesive strength was measured, the adhesive residue on the stainless steel plate due to poor adhesion of the plating and poor adhesion of the adhesive was evaluated.
◯: No glue residue.
X: There is adhesive residue of 10% or more.

１導電性基材
２導電性粘着剤層
３ガラスパネル
４粘着剤層
５銅箔
６スズメッキ
７導電性粘着シート 1 Conductive base material 2 Conductive adhesive layer 3 Glass panel 4 Adhesive layer 5 Copper foil 6 Tin-plated 7 Conductive adhesive sheet

Claims

A conductive pressure-sensitive adhesive sheet having a conductive base material and a conductive pressure-sensitive adhesive layer.
The conductive pressure-sensitive adhesive layer comprises a (meth) acrylic pressure-sensitive adhesive composition containing a (meth) acrylic copolymer, a triazole-based compound, a cross-linking agent , and conductive particles.
The (meth) acrylic copolymer contains a carboxyl group-containing (meth) acrylic copolymer (A) having a weight average molecular weight of 500,000 to 2 million and a nitrogen atom having a weight average molecular weight of 5,000 to 100,000. Meta) Containing acrylic copolymer (B),
The carboxyl group-containing (meth) acrylic copolymer (A) contains a (meth) acrylate monomer having 2 to 14 carbon atoms, a vinyl monomer having a functional group that reacts with the cross-linking agent, and a carboxyl group-containing (meth). It is a polymer copolymerized with an acrylate monomer.
The content of the (meth) acrylate monomer having 2 to 14 carbon atoms in the carboxyl group-containing (meth) acrylic copolymer (A) is 90% by mass to 96% by mass.
The content of the vinyl monomer in the carboxyl group-containing (meth) acrylic copolymer (A) is 0.01% by mass to 1.0% by mass.
The content of the carboxyl group-containing (meth) acrylate monomer in the carboxyl group-containing (meth) acrylic copolymer (A) is 1% by mass to 8% by mass.
The nitrogen atom-containing (meth) acrylic copolymer (B) is a polymer obtained by copolymerizing a (meth) acrylate monomer having 1 to 8 carbon atoms and a nitrogen atom-containing vinyl monomer.
The content of the (meth) acrylate monomer having 1 to 8 carbon atoms in the nitrogen atom-containing (meth) acrylic copolymer (B) is 70% by mass to 99% by mass.
The content of the nitrogen atom-containing vinyl monomer in the nitrogen atom-containing (meth) acrylic copolymer (B) is 1% by mass to 30% by mass.
With respect to the carboxyl group-containing (meth) acrylic copolymer (A) 100 parts by mass of, Ri mass 5 parts by mass to 50 parts by mass der of the nitrogen atom-containing (meth) acrylic copolymer (B),
The (meth) acrylic pressure-sensitive adhesive composition 100 parts by weight with respect to (the solid content), a conductive adhesive sheet weight of the triazole-based compound, characterized in 0.05 parts by 3.0 parts by mass der Rukoto.

The conductive pressure-sensitive adhesive sheet according to claim 1, wherein the conductive particles are in the shape of beads.

The first or second claim, wherein the content of the conductive particles in the conductive pressure-sensitive adhesive layer is 20 to 100 parts by mass with respect to 100 parts by mass (solid content) of the (meth) acrylic pressure-sensitive adhesive composition. Conductive adhesive sheet.

The conductive pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the conductive base material is a conductive base material containing copper.

The conductive pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the conductive base material is a copper foil base material that has been subjected to an inorganic rust preventive treatment.

One of claims 1 to 3, wherein the conductive base material is a conductive base material obtained by plating a wet polyester-based non-woven base material, and the plating includes a non-electrolytic metal plating. The conductive pressure-sensitive adhesive sheet according to item 1.

The conductive adhesive sheet according to any one of claims 1 to 6 , wherein the sticking area is 10 mm × 10 mm or less.

The conductive adhesive sheet according to any one of claims 1 to 7 , which is used by being attached to a built-in component of a small electronic terminal.